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Common Stock and Incentive Awards - Additional Information (Details) - USD ($)				3 Months Ended		12 Months Ended
	Jan. 22, 2016	Jan. 23, 2015	Sep. 19, 2014	Mar. 31, 2016	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares authorized						100,000,000	100,000,000
Common stock, par value per share			$ 0.00001			$ 0.00001	$ 0.00001
Stock-based compensation expense						$ 3,341,000	$ 1,488,000
Summary of the RSU activity
Cash received from the exercise of stock options						$ 400,000		$ 200,000
Exercise of stock options					76,633	132,900	0
Expired of stock options						10,000	86,000
Tax benefit recognized from stock option exercises						$ 800,000
Ex Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Severance Costs				$ 1,400,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period						1 year
Minimum \| Plan 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Payout range as a percent of award target						0.00%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance period						2 years
Maximum \| Plan 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Payout range as a percent of award target						200.00%
RSU and Performance Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense						$ 3,300,000	$ 1,500,000	$ 0
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period						3 years
Performance Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in shares)						176,632	475,409
Percentage of target to be achieved to be eligible to receive performance awards						96.50%	135.00%
Performance Awards \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period						1 year
Performance Awards \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period						2 years
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in shares)						410,694	917,283	0
Fair value, per unit	$ 10.77
Unrecognized compensation expense						$ 2,500,000
Recognition period of unrecognized compensation cost						1 year 4 months 28 days
Restricted Stock Units (RSUs) \| Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in shares)	367,519	685,606
Fair value, per unit		$ 4.03
Restricted Stock Units (RSUs) \| Ex Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense				$ 500,000
Summary of the RSU activity
Vested				167,511
Restricted Stock Units (RSUs) \| Non Employee Board
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in shares)	34,920	89,900
Fair value, per unit		$ 4.03
Restricted Stock Units (RSUs) \| Plan 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted (in shares)						14,661	9,171
Converted to a Right to Receive $ 6.05 Per Share
Summary of the RSU activity
Number of shares converted			5,785,123
MTR Gaming 2010 Long Term Incentive Plan
Summary of the RSU activity
Right to receive per share			$ 6.05
Converted to a Right to Receive One Share of ERI Stock
Summary of the RSU activity
Number of shares converted			22,600,961
Number of shares granted on conversion (per share)			1