Entity Central Index Key Represents the amount of the operating expense reported by an equity method investment of the entity. Represents the amount of the operating income reported by an equity method investment of the entity. Represents the amount of the other income (expense) reported by an equity method investment of the entity. Represents the amount of expenses excluding depreciation and amortization. Represents the corporate expenses incurred during the reporting period. Gain on valuation of unconsolidated affiliate. Gain on termination of supplemental executive retirement plan. Carrying amount of land and undeveloped properties that management intend to sell in the future. Represents the gross amount of revenues before promotional allowance deduction. Costs incurred in pari-mutuel operations. Amount of expenses relating to gaming activities. Amount of expenses from non gaming activities. General, administrative and corporate expenses. Represents amount reimbursed towards capital expenditure. Reflects the call premium on early repayment of debt. Document and entity information. Document And Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well Known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Represents the carrying value as of the balance sheet date of obligations incurred and payable for gaming taxes and assessments. Statement Of Financial Position [Abstract] ASSETS Assets [Abstract] CURRENT ASSETS: Assets Current [Abstract] Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Restricted cash Restricted Cash And Cash Equivalents At Carrying Value Accounts receivable, net Accounts Receivable Net Current Inventories Inventory Net Prepaid income taxes Prepaid Taxes Prepaid expenses and other Prepaid Expense And Other Assets Current Total current assets Assets Current INVESTMENT IN AND ADVANCES TO UNCONSOLIDATED AFFILIATES Equity Method Investments PROPERTY AND EQUIPMENT, NET Property Plant And Equipment Net GAMING LICENSES AND OTHER INTANGIBLES, NET Intangible Assets Net Excluding Goodwill GOODWILL Goodwill NON-OPERATING REAL PROPERTY Non Operating Real Property OTHER ASSETS, NET Other Assets Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities And Stockholders Equity [Abstract] CURRENT LIABILITIES: Liabilities Current [Abstract] Current portion of long-term debt Long Term Debt Current Accounts payable Accounts Payable Current Due to affiliates Due To Affiliate Current Accrued property, gaming and other taxes Accrued Gaming Taxes And Assessments Accrued payroll and related Employee Related Liabilities Current Accrued interest Interest Payable Current Accrued other liabilities Other Accrued Liabilities Current Total current liabilities Liabilities Current LONG-TERM DEBT, LESS CURRENT PORTION Long Term Debt Noncurrent DEFERRED INCOME TAXES Deferred Tax Liabilities Noncurrent OTHER LONG-TERM LIABILITIES Other Liabilities Noncurrent Total liabilities Liabilities COMMITMENTS AND CONTINGENCIES (Note 16) Commitments And Contingencies STOCKHOLDERS' EQUITY: Stockholders Equity [Abstract] Common stock, 100,000,000 shares authorized, 47,105,744 and 46,817,829 issued and outstanding, par value $0.00001 as of December 31, 2016 and 2015, respectively Common Stock Value Paid-in capital Additional Paid In Capital Common Stock Retained earnings Retained Earnings Accumulated Deficit Accumulated other comprehensive income Accumulated Other Comprehensive Income Loss Net Of Tax Total stockholders’ equity Stockholders Equity Including Portion Attributable To Noncontrolling Interest Total liabilities and stockholders’ equity Liabilities And Stockholders Equity Common stock, shares authorized Common Stock Shares Authorized Common stock, shares issued Common Stock Shares Issued Common stock, shares outstanding Common Stock Shares Outstanding Common stock, par value (in dollars per share) Common Stock Par Or Stated Value Per Share Revenue earned from pari-mutuel commissions, which is a predetermined percentage of the total amount wagered during the period, by the entity. Represents the gain on termination of supplemental executive retirement plan assets of unconsolidated affiliate. Income Statement [Abstract] REVENUES: Sales Revenue Net [Abstract] Casino Casino Revenue Pari-mutuel commissions Pari Mutuel Commissions Revenue Food and beverage Food And Beverage Revenue Hotel Revenue From Owned Hotels Other Other Sales Revenue Net Gross revenues Revenues Gross Less-promotional allowances Promotional Allowances Net operating revenues Revenues EXPENSES: Costs And Expenses [Abstract] Casino Casino Expenses Pari-mutuel commissions Pari Mutuel Commissions Food and beverage Food And Beverage Cost Of Sales Hotel Occupancy Costs Other Other Cost Of Operating Revenue Marketing and promotions Marketing And Advertising Expense General and administrative General And Administrative Expense Corporate Corporate Expense Depreciation and amortization Depreciation And Amortization Total operating expenses Operating Costs And Expenses LOSS ON SALE OR DISPOSAL OF PROPERTY Gain Loss On Sale Of Property Plant Equipment ACQUISITION CHARGES Acquisition Costs EQUITY IN INCOME OF UNCONSOLIDATED AFFILIATES Income Loss From Equity Method Investments OPERATING INCOME Operating Income Loss OTHER INCOME (EXPENSE): Nonoperating Income Expense [Abstract] Interest expense, net Interest Expense Gain on valuation of unconsolidated affiliate Gain On Valuation Of Unconsolidated Affiliate Gain on termination of supplemental executive retirement plan Gain On Termination Of Supplemental Executive Retirement Plan Assets Of Unconsolidated Affiliate Loss on early retirement of debt, net Gains Losses On Extinguishment Of Debt Total other expense Other Nonoperating Income Expense NET INCOME (LOSS) BEFORE INCOME TAXES Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest (PROVISION) BENEFIT FOR INCOME TAXES Income Tax Expense Benefit NET INCOME (LOSS) Profit Loss NON-CONTROLLING INTEREST Net Income Loss Attributable To Noncontrolling Interest NET INCOME (LOSS) ATTRIBUTABLE TO ERI, INC. Net Income Loss Net Income (Loss) per share of Common Stock: Earnings Per Share Basic And Diluted [Abstract] Basic Earnings Per Share Basic Diluted Earnings Per Share Diluted Weighted average number of shares outstanding: Weighted Average Number Of Shares Outstanding [Abstract] Weighted Average Basic Shares Outstanding Weighted Average Number Of Shares Outstanding Basic Weighted Average Diluted Shares Outstanding Weighted Average Number Of Diluted Shares Outstanding Statement Of Income And Comprehensive Income [Abstract] NET INCOME (LOSS) Other Comprehensive Income (Loss), net of tax: Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Defined benefit pension plan—amortization of net (loss) gain Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax Minimum pension liability adjustment of unconsolidated affiliate Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax Total Comprehensive Income (Loss) Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Less: Comprehensive income attributable to non-controlling interest Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest Comprehensive Income (Loss), net of tax Comprehensive Income Net Of Tax represents the number of shares returned from escrow to authorized share capital. Represents the value of shares held related to net share settlement of stock awards. Represents the number of shares withheld related to net share settlement of stock awards. Noncontrolling interest increase from business combination number of shares issued. Statement Of Stockholders Equity [Abstract] Statement [Table] Statement [Table] Equity Components Statement Equity Components [Axis] Equity Component Equity Component [Domain] Common Stock Common Stock [Member] Paid-in Capital Additional Paid In Capital [Member] Retained Earnings (Deficit) Retained Earnings [Member] Non-controlling Interest Noncontrolling Interest [Member] Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income [Member] Statement [Line Items] Statement [Line Items] Beginning Balance Beginning Balance (in shares) Shares Outstanding Noncash distribution of investment in Tamarack Crossing, LLC Transfer Of Investments Cash distributions Dividends Common Stock Cash MTR Gaming shares converted upon reverse merger Stock Issued During Period Value Acquisitions MTR Gaming shares converted upon reverse merger (in shares) Stock Issued During Period Shares Acquisitions Escrow shares returned to authorized and unissued (in shares) Escrow Shares Returned To Authorized Share Capital Issuance of restricted stock units Stock Issued During Period Value Share Based Compensation Issuance of restricted stock units (in shares) Stock Issued During Period Shares Share Based Compensation Acquisition of non-controlling interest Noncontrolling Interest Increase From Business Combination Acquisition of non-controlling interest (in shares) Noncontrolling Interest Increase From Business Combination Number Of Shares Issued Net income (loss) Pension other comprehensive gain, net of tax Exercise of stock options Stock Issued During Period Value Stock Options Exercised Exercise of stock options (in shares) Stock Issued During Period Shares Stock Options Exercised Shares withheld related to net share settlement of stock awards Shares Withheld Related To Settlement Of Stock Awards Value Shares withheld related to net share settlement of stock awards (in shares) Shares Withheld Related To Settlement Of Stock Awards Ending Balance Ending Balance (in shares) Pension other comprehensive gain, tax Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax Provision (benefit) for doubtful accounts. Represents the increase (decrease) during the reporting period in accrued and other liabilities and due to members and affiliates incurred but not yet paid. Value of equipment acquired under capital leases during the period Statement Of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided By Used In Operating Activities Continuing Operations [Abstract] Adjustments to reconcile net income (net loss) to net cash provided by operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Amortization of debt issuance costs and (premium) discount Amortization Of Financing Costs And Discounts Equity in income of unconsolidated affiliates Gain on termination of supplemental executive retirement plan assets of unconsolidated affiliate Loss on early retirement of debt, net Gain on valuation of unconsolidated affiliate Distributions from unconsolidated affiliate Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital Change in fair value of acquisition related contingencies Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss Stock-based compensation expense Allocated Share Based Compensation Expense Loss on sale or disposal of property Provision (benefit) for bad debt Provision Benefit For Doubtful Accounts Provision (benefit) for deferred income taxes Deferred Income Tax Expense Benefit Change in operating assets and liabilities: Increase Decrease In Operating Capital [Abstract] Restricted cash Increase Decrease In Restricted Cash Accounts receivable Increase Decrease In Accounts Receivable Inventories Increase Decrease In Inventories Prepaid expenses and other Increase Decrease In Prepaid Expense Accounts payable Increase Decrease In Accounts Payable Interest payable Increase Decrease In Interest Payable Net Income taxes payable Increase Decrease In Accrued Income Taxes Payable Accrued and other liabilities and due to affiliates Accrued And Other Liabilities And Due To Members And Affiliates Net cash provided by operating activities Net Cash Provided By Used In Operating Activities Continuing Operations CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided By Used In Investing Activities Continuing Operations [Abstract] Capital expenditures, net of payables Payments To Acquire Property Plant And Equipment Investment in and loans to unconsolidated affiliate Payments To Acquire Equity Method Investments Net cash (used) acquired in business combinations Payments For Proceeds From Businesses And Interest In Affiliates Proceeds from sale of property and equipment Proceeds From Sale Of Property Plant And Equipment Decrease in restricted cash due to credit support deposit Decrease In Restricted Cash Reimbursement of capital expenditures from West Virginia regulatory authorities Capital Expenditure Reimbursed By Racing Commission Decrease (increase) in other assets, net Increase Decrease In Other Noncurrent Assets Net cash (used in) provided by investing activities Net Cash Provided By Used In Investing Activities Continuing Operations CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided By Used In Financing Activities Continuing Operations [Abstract] Proceeds from issuance of Senior Notes Proceeds From Issuance Of Senior Long Term Debt (Payments) proceeds from issuance of Term Loan Proceeds From Repayments Of Lines Of Credit Borrowings under Revolving Credit Facility Proceeds From Lines Of Credit Payments under Revolving Credit Facility Repayments Of Lines Of Credit Principal payments under Senior Notes Repayments Of Senior Debt Retirement of long-term debt Repayments Of Long Term Debt Principal payments on capital leases Repayments Of Long Term Capital Lease Obligations Debt issuance costs Payments Of Debt Issuance Costs Call premium on early retirement of debt Call Premium On Early Repayment Of Debt Taxes paid related to net share settlement of equity awards Payments Related To Tax Withholding For Share Based Compensation Cash distributions Payments Of Capital Distribution Proceeds from exercise of stock options Proceeds From Stock Options Exercised Net cash (used in) provided by financing activities Net Cash Provided By Used In Financing Activities Continuing Operations (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS Net Cash Provided By Used In Continuing Operations CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR CASH AND CASH EQUIVALENTS, END OF YEAR SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION: Supplemental Cash Flow Information [Abstract] Interest paid Interest Paid Local income taxes paid Income Taxes Paid Noncash distribution of Tamarack investment Payables for capital expenditures Capital Expenditures Incurred But Not Yet Paid Equipment acquired under capital leases Equipment Acquired Under Capital Leases Organization Consolidation And Presentation Of Financial Statements [Abstract] Organization and Basis of Presentation Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Text Block] Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Acquisition and Preliminary Purchase Accounting. Reno Acquisition, MTR Merger and Final Purchase Accounting Business Combination Disclosure [Text Block]