Revenue Recognition - Summary of Net Revenues Disaggregated Type of Revenue and Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Net revenues	$ 487,253	$ 472,878	$ 1,384,247	$ 1,050,897
Casino
Disaggregation Of Revenue [Line Items]
Net revenues	362,877	347,537	1,046,010	764,684
Pari-mutuel Commissions
Disaggregation Of Revenue [Line Items]
Net revenues	5,292	5,111	14,407	9,859
Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	58,153	59,537	164,644	141,667
Hotel
Disaggregation Of Revenue [Line Items]
Net revenues	44,780	45,962	114,447	99,545
Other
Disaggregation Of Revenue [Line Items]
Net revenues	16,151	14,731	44,739	35,142
Corporate
Disaggregation Of Revenue [Line Items]
Net revenues	139	173	377	366
Corporate | Other
Disaggregation Of Revenue [Line Items]
Net revenues	139	173	377	366
West Segment | Operating Segment
Disaggregation Of Revenue [Line Items]
Net revenues	129,092	134,324	346,550	297,564
West Segment | Operating Segment | Casino
Disaggregation Of Revenue [Line Items]
Net revenues	60,912	63,501	168,342	132,563
West Segment | Operating Segment | Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	27,502	30,099	76,524	74,593
West Segment | Operating Segment | Hotel
Disaggregation Of Revenue [Line Items]
Net revenues	31,583	31,737	77,234	69,596
West Segment | Operating Segment | Other
Disaggregation Of Revenue [Line Items]
Net revenues	9,095	8,987	24,450	20,812
Midwest Segment | Operating Segment
Disaggregation Of Revenue [Line Items]
Net revenues	99,834	103,651	301,235	171,292
Midwest Segment | Operating Segment | Casino
Disaggregation Of Revenue [Line Items]
Net revenues	86,331	89,482	262,138	147,469
Midwest Segment | Operating Segment | Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	6,867	7,572	20,527	12,607
Midwest Segment | Operating Segment | Hotel
Disaggregation Of Revenue [Line Items]
Net revenues	4,720	4,828	12,775	8,282
Midwest Segment | Operating Segment | Other
Disaggregation Of Revenue [Line Items]
Net revenues	1,916	1,769	5,795	2,934
South Segment | Operating Segment
Disaggregation Of Revenue [Line Items]
Net revenues	106,569	107,934	341,612	228,954
South Segment | Operating Segment | Casino
Disaggregation Of Revenue [Line Items]
Net revenues	84,299	84,447	270,802	176,616
South Segment | Operating Segment | Pari-mutuel Commissions
Disaggregation Of Revenue [Line Items]
Net revenues	1,854	1,766	7,853	3,271
South Segment | Operating Segment | Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	12,492	12,669	38,936	29,231
South Segment | Operating Segment | Hotel
Disaggregation Of Revenue [Line Items]
Net revenues	6,169	7,207	18,462	15,706
South Segment | Operating Segment | Other
Disaggregation Of Revenue [Line Items]
Net revenues	1,755	1,845	5,559	4,130
East Segment | Operating Segment
Disaggregation Of Revenue [Line Items]
Net revenues	127,722	126,796	370,576	352,721
East Segment | Operating Segment | Casino
Disaggregation Of Revenue [Line Items]
Net revenues	109,637	110,107	323,030	308,036
East Segment | Operating Segment | Pari-mutuel Commissions
Disaggregation Of Revenue [Line Items]
Net revenues	3,438	3,345	6,554	6,588
East Segment | Operating Segment | Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	9,359	9,197	26,724	25,236
East Segment | Operating Segment | Hotel
Disaggregation Of Revenue [Line Items]
Net revenues	2,308	2,190	5,976	5,961
East Segment | Operating Segment | Other
Disaggregation Of Revenue [Line Items]
Net revenues	2,980	$ 1,957	8,292	$ 6,900
Central Segment | Operating Segment
Disaggregation Of Revenue [Line Items]
Net revenues	23,897		23,897
Central Segment | Operating Segment | Casino
Disaggregation Of Revenue [Line Items]
Net revenues	21,698		21,698
Central Segment | Operating Segment | Food and Beverage
Disaggregation Of Revenue [Line Items]
Net revenues	1,933		1,933
Central Segment | Operating Segment | Other
Disaggregation Of Revenue [Line Items]
Net revenues	$ 266		$ 266