Revenue Recognition (Disaggregation Of Company's Revenue From Contracts With Customers) (Details) - USD ($) $ in Thousands	3 Months Ended														12 Months Ended
	Dec. 31, 2020	[1]	Sep. 30, 2020	Jun. 30, 2020	[2]	Mar. 31, 2020	[3]	Dec. 31, 2019	[4]	Sep. 30, 2019	[4]	Jun. 30, 2019	[5]	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Net operating revenue	$ 84,801		$ 95,706	$ 36,103		$ 87,656		$ 67,236		$ 52,935		$ 52,445		$ 45,613	$ 304,268	$ 218,227	$ 168,938
Corporate And Other [Member]
Disaggregation of Revenue [Line Items]
Net operating revenue															1,413	5,685	5,885
United States [Member]
Disaggregation of Revenue [Line Items]
Net operating revenue															198,344	49,998	33,483
Canada [Member]
Disaggregation of Revenue [Line Items]
Net operating revenue															50,240	80,650	61,361
Poland [Member]
Disaggregation of Revenue [Line Items]
Net operating revenue															54,271	81,894	68,209
Gaming [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															253,281	176,866	140,301
Gaming [Member] | Corporate And Other [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															830	4,302	4,806
Gaming [Member] | United States [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															168,904	42,285	27,736
Gaming [Member] | Canada [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															30,319	49,450	40,470
Gaming [Member] | Poland [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															53,228	80,829	67,289
Hotel [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															5,910	2,521	1,986
Hotel [Member] | United States [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															5,826	2,030	1,444
Hotel [Member] | Canada [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															84	491	542
Food And Beverage [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															16,194	20,022	15,742
Food And Beverage [Member] | Corporate And Other [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															105	799	501
Food And Beverage [Member] | United States [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															9,795	4,804	3,931
Food And Beverage [Member] | Canada [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															5,832	13,507	10,528
Food And Beverage [Member] | Poland [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															462	912	782
Other [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															28,883	18,818	10,909
Pari-Mutuel And Other [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															28,883	18,818	10,909
Pari-Mutuel And Other [Member] | Corporate And Other [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															478	584	578
Pari-Mutuel And Other [Member] | United States [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															13,819	879	372
Pari-Mutuel And Other [Member] | Canada [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															14,005	17,202	9,821
Pari-Mutuel And Other [Member] | Poland [Member]
Disaggregation of Revenue [Line Items]
Operating revenue															$ 581	$ 153	$ 138

[1] The Company sold the casino operations of CAL. See Note 1. Casinos in Canada and Poland were temporarily closed in December 2020 to comply with quarantines issued by governments to contain the spread of COVID-19.

[2] The Company’s casinos were temporarily closed during the quarter and the Company permanently closed CCB and deconsolidated CCB. See Note 1.

[3] The Company impaired assets related to goodwill and intangible assets due to triggering events caused by COVID-19. See Notes 4 and 6.

[4] The Company completed the Acquisition in December 2019. See Note 3. In addition, the Company impaired assets related to CCB in December 2019. See Notes 5, 6 and 10.

[5] CMR began operating in April 2019.