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Fair value of intangible assets, measurement with unobservable inputs estimated discount rate.

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Percentage of workforce furlough due to closures of properties.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Organization and Basis of Presentation - Additional Information (Details) $ in Thousands		1 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended
	Jan. 21, 2020 USD ($)	Sep. 30, 2018 seat	Mar. 31, 2020 USD ($)	Jun. 30, 2020 USD ($) a	Jun. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)	Mar. 13, 2020 USD ($)
Organization And Basis Of Presentation [Line Items]
Number of seats \| seat		5,000
Business acquisition property operations term (in years)				21 years
Contract assets				$ 127,700		$ 53,200
Contract related liabilities				60,286		71,248
Impairment charge related to intangible assets				126,596	$ 0
Consideration transferred	$ 15,800			10,750	$ 0	5,000
Mohegan Sun Pocono
Organization And Basis Of Presentation [Line Items]
Contract related liabilities				$ 17,100		$ 18,000
Fair value of intangible assets, measurement with unobservable inputs estimated discount rate			10.50%
Impairment charge related to intangible assets			$ 126,600
COVID-19 \| Connecticut and Pennsylvania Properties
Organization And Basis Of Presentation [Line Items]
Percentage of workforce furloughed due to closure of properties				98.00%
Remaining furloughed percentage				50.00%
COVID-19 \| Connecticut and Pennsylvania Properties \| Gaming
Organization And Basis Of Presentation [Line Items]
Number of months obtained for tax payments forbearance				3 months
Senior Secured Revolving Credit Facilities \| COVID-19
Organization And Basis Of Presentation [Line Items]
Remaining balance drawn							$ 125,000
Salishan-Mohegan and Cowlitz Project
Organization And Basis Of Presentation [Line Items]
Ownership percentage				100.00%
Casinos Holding Company and Subsidiaries
Organization And Basis Of Presentation [Line Items]
Ownership percentage				10.00%
Inspire Integrated Resort and MGA Korea
Organization And Basis Of Presentation [Line Items]
Ownership percentage				100.00%
Mohegan Hotel Holdings, LLC
Organization And Basis Of Presentation [Line Items]
Ownership percentage	45.00%
Mohegan Sun
Organization And Basis Of Presentation [Line Items]
Size of gaming and entertainment complex (in acres) \| a				196
Mohegan Sun Pocono
Organization And Basis Of Presentation [Line Items]
Size of gaming and entertainment complex (in acres) \| a				400