ORGANIZATION AND BASIS OF PRESENTATION - Mohegan Sun Casino at Virgin Hotels Las Vegas (Details) ft² in Thousands, $ in Millions	1 Months Ended	6 Months Ended
Jul. 31, 2019 USD ($) ft²	Mar. 31, 2021
Virgin Hotels Las Vegas
Lessee, Lease, Description [Line Items]
Area of real estate \| ft²	60
Term of lease	20 years
Annual lease payment	$ 9.0
Annual payments maximum amount	$ 15.0
MGNV LLC
Lessee, Lease, Description [Line Items]
Ownership percentage		100.00%

Lessee, Operating Lease, Annual Payments

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- Definition

Lessee, Operating Lease, Annual Payments Maximum Amount

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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