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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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INCOME TAXES INCOME TAXES - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Nov. 18, 2020 USD ($)	Mar. 28, 2019 USD ($)	Dec. 31, 2017 USD ($)
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 0	$ 0
Increase (decrease) in net deferred tax liabilities	23,200,000	(3,700,000)
Deferred income taxes	1,191,000	8,995,000	$ 5,880,000
Tax effect	588,000	852,000
CARES Act	(33,347,000)	0	0
Income tax benefit		(100,000)
Tax contingency accruals		0
Unrecognized tax benefits	0	0	400,000			$ 445,000
Cash tax payments	3,835,000	16,519,000	$ 22,217,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	3,100,000	600,000
Delaware \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	3,800,000	2,600,000
Colorado \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	12,100,000	3,600,000
Louisiana \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	22,700,000	0
Missouri \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	15,500,000	0
New Jersey \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	17,200,000	0
Rhode Island \| State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	65,300,000	0
Dover Downs
Operating Loss Carryforwards [Line Items]
Deferred income tax assets		$ 11,900,000			$ 11,879,000
Bally’s Atlantic City
Operating Loss Carryforwards [Line Items]
Deferred tax liabilities	11,100,000			$ 11,132,000
Eldorado Resort Casino Shreveport
Operating Loss Carryforwards [Line Items]
Deferred tax liabilities	$ 11,500,000
Membership interest	1
2020 Business combinations
Operating Loss Carryforwards [Line Items]
Deferred income tax assets	$ 22,600,000