ACQUISITIONS - Narrative (Details)											1 Months Ended		3 Months Ended	6 Months Ended	11 Months Ended	12 Months Ended
	Feb. 05, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	Dec. 23, 2020 USD ($)	Nov. 18, 2020 USD ($) shares	Oct. 27, 2020 USD ($) contractOption	Sep. 30, 2020 USD ($)	Jul. 01, 2020 USD ($)	Apr. 24, 2020 USD ($)	Jan. 23, 2020 USD ($) casino	Mar. 28, 2019 USD ($) shares	Jan. 31, 2021 shares	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jan. 22, 2021 shares	Mar. 31, 2020 USD ($)
Business Acquisition [Line Items]
Total consideration paid, net of cash acquired																$ 425,063,000	$ 9,606,000	$ 0
Transaction costs																13,237,000	10,900,000	6,844,000
Number of businesses acquired | casino									3
Gain on bargain purchases																63,871,000	0	0
Dover Downs
Business Acquisition [Line Items]
Percentage of common stock owned by acquiree										7.225%
Stock issued for purchase of Dover Downs (in shares) | shares										2,976,825
Consideration transferred										$ 115,886,000
Total consideration paid, net of cash acquired										96,400,000
Cash acquired										19,500,000
Transaction costs																59,000	7,883,000	6,636,000
Intangible assets										5,110,000
Net revenue from date of acquisition																65,000,000.0	80,800,000
Net income from date of acquisition																3,300,000	6,000,000.0
Cash paid to acquire business										29,096,000
Common stock issued										86,790,000
Dover Downs | Rated player relationships
Business Acquisition [Line Items]
Intangible assets										$ 800,000
Acquired intangible assets, useful life										8 years
Dover Downs | Trademarks
Business Acquisition [Line Items]
Intangible assets										$ 3,900,000
Acquired intangible assets, useful life										10 years
Dover Downs | Hotel and conference pre-bookings
Business Acquisition [Line Items]
Intangible assets										$ 400,000
Acquired intangible assets, useful life										3 years
Black Hawk
Business Acquisition [Line Items]
Consideration transferred									$ 53,800,000
Total consideration paid, net of cash acquired									50,500,000
Transaction costs																1,000,000.0	1,700,000
Net revenue from date of acquisition															$ 17,800,000
Black Hawk | Rated player relationships
Business Acquisition [Line Items]
Intangible assets									$ 600,000
Acquired intangible assets, useful life									6 years
Black Hawk | Trademarks
Business Acquisition [Line Items]
Intangible assets									$ 2,100,000
Acquired intangible assets, useful life									10 years
Black Hawk | Novelty game licenses
Business Acquisition [Line Items]
Intangible assets									$ 3,300,000											$ 0
Casino KC & Casino Vicksburg
Business Acquisition [Line Items]
Consideration transferred							$ 229,900,000
Total consideration paid, net of cash acquired							225,500,000
Adjusted purchase price														$ (137,000)
Transaction costs																1,828,000	1,293,000	0
Intangible assets		$ 138,160,000					$ 139,760,000					$ 138,160,000	$ 138,160,000	138,160,000	138,160,000	138,160,000
Net revenue from date of acquisition														40,100,000
Net income from date of acquisition														8,500,000
Bally’s Atlantic City
Business Acquisition [Line Items]
Consideration transferred				$ 24,700,000
Total consideration paid, net of cash acquired				16,100,000
Estimated total cost of project		90,000,000		90,000,000								90,000,000	90,000,000	$ 90,000,000	$ 90,000,000	90,000,000
Present value of reimbursement				27,700,000
Adjusted purchase price				(900,000)
Transaction costs																4,373,000	0	0
Intangible assets				1,120,000
Net revenue from date of acquisition												$ 8,700,000
Reimbursement of capital expenditure commitment				30,000,000
Gain on bargain purchases				32,595,000									$ 32,600,000
Bally’s Atlantic City | Rated player relationships
Business Acquisition [Line Items]
Intangible assets				$ 900,000
Acquired intangible assets, useful life				8 years
Bally’s Atlantic City | Hotel and conference pre-bookings
Business Acquisition [Line Items]
Intangible assets				$ 200,000
Acquired intangible assets, useful life				3 years
Bally’s Atlantic City | Accrued liabilities
Business Acquisition [Line Items]
Liability				$ 2,000,000.0
Eldorado Resort Casino Shreveport
Business Acquisition [Line Items]
Consideration transferred			$ 137,200,000
Total consideration paid, net of cash acquired			133,100,000
Cash acquired			5,000,000.0
Transaction costs			3,100,000													3,108,000	0	0
Intangible assets			58,140,000
Net revenue from date of acquisition		2,500,000
Net income from date of acquisition		$ 1,900,000
Gain on bargain purchases			31,276,000
Receivable from a networking capital adjustment			800,000
Eldorado Resort Casino Shreveport | Rated player relationships
Business Acquisition [Line Items]
Intangible assets			$ 400,000
Acquired intangible assets, useful life			8 years
Eldorado Resort Casino Shreveport | Novelty game licenses
Business Acquisition [Line Items]
Intangible assets			$ 57,700,000
MontBleu
Business Acquisition [Line Items]
Consideration transferred								$ 15,000,000.0
Transaction costs																1,052,000	0	0
Jumer’s Hotel & Casino
Business Acquisition [Line Items]
Consideration transferred						$ 120,000,000.0
Transaction costs																1,003,000	0	0
Deposit for pending acquisition of Jumer’s Casino & Hotel						4,000,000.0										4,000,000.0
Jumer’s Hotel & Casino | Nonrefundable deposit
Business Acquisition [Line Items]
Deposit for pending acquisition of Jumer’s Casino & Hotel						$ 2,000,000.0
Tropicana Evansville
Business Acquisition [Line Items]
Consideration transferred					$ 140,000,000.0
Transaction costs																661,000	$ 0	$ 0
Deposit for pending acquisition of Jumer’s Casino & Hotel																$ 16,800,000
Tropicana Evansville | Dover Downs real estate
Business Acquisition [Line Items]
Purchase price					144,000,000.0
Tropicana Evansville | Tropicana Evansville
Business Acquisition [Line Items]
Annual rent					$ 28,000,000.0
Term of contract					15 years
Number of renewal terms | contractOption					4
Renewal term					5 years
Tropicana Evansville | GLPI
Business Acquisition [Line Items]
Acquiring price					$ 340,000,000.0
Bet.Works
Business Acquisition [Line Items]
Stock issued for purchase of Dover Downs (in shares) | shares				2,528,194
Payments of capital distribution				$ 62,500,000
Cash paid to acquire business				$ 62,500,000
Common stock issued (in shares) | shares				2,528,194
Monkey Knife Fight | Penny warrant | Subsequent event
Business Acquisition [Line Items]
Common stock available to acquire (in shares) | shares																			984,450
Aditional common stock available to acquire (in shares) | shares											787,550
Horses Mouth Limited (SportCaller) | Subsequent event
Business Acquisition [Line Items]
Cash paid to acquire business	$ 24,000,000.0
Common stock issued (in shares) | shares	221,391
Common stock issued	$ 12,000,000.0
Exchange ratio	0.8334
Dover Downs real estate | Dover Downs real estate
Business Acquisition [Line Items]
Annual rent					$ 12,000,000.0
Term of contract					15 years
Number of renewal terms | contractOption					4
Renewal term					5 years