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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended	12 Months Ended
SEGMENT REPORTING (Details) $ in Thousands	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($) segment	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment		4
Impairment of Mohegan Sun Pocono's goodwill	$ 39,459	$ 39,459	$ 0	$ 0
Revenues:
Revenues	1,388,810	1,388,810	1,456,980	1,485,350
Total	1,388,810	1,388,810	1,355,632	1,380,003
Income Statement [Abstract]
Income (loss) from operations:	136,462	136,462	244,534	257,235
Capital [Abstract]
Capital expenditures incurred:		80,994	122,802	101,533
ASSETS
Total assets:	2,511,596	2,511,596	2,312,119
Operating segments \| Mohegan Sun
Revenues:
Revenues		992,043	1,068,892	1,079,920
Income Statement [Abstract]
Income (loss) from operations:		156,276	230,890	249,403
Capital [Abstract]
Capital expenditures incurred:		30,931	93,165	57,033
ASSETS
Total assets:	1,282,384	1,282,384	1,364,169
Operating segments \| Mohegan Sun Pocono
Revenues:
Revenues		251,054	265,691	278,938
Income Statement [Abstract]
Income (loss) from operations:		(5,253)	37,541	33,145
Capital [Abstract]
Capital expenditures incurred:		6,526	9,889	6,897
ASSETS
Total assets:	548,424	548,424	581,079
Operating segments \| MGE Niagara Resorts
Revenues:
Revenues		112,525	0	0
Income Statement [Abstract]
Income (loss) from operations:		7,368	0	0
Capital [Abstract]
Capital expenditures incurred:		3,389	0	0
ASSETS
Total assets:	342,821	342,821	0
Operating segments \| Management, development and other
Revenues:
Revenues		33,349	19,806	100,505
Income Statement [Abstract]
Income (loss) from operations:		1,152	(686)	76,647
Capital [Abstract]
Capital expenditures incurred:		40,114	19,724	37,603
ASSETS
Total assets:	313,458	313,458	333,202
Corporate
Revenues:
Revenues		1,001	1,483	1,951
Income Statement [Abstract]
Income (loss) from operations:		(22,161)	(23,211)	(101,960)
Capital [Abstract]
Capital expenditures incurred:		34	24	0
ASSETS
Total assets:	912,712	912,712	838,454
Inter-segment
Revenues:
Revenues		(1,162)	(240)	(81,311)
Income Statement [Abstract]
Income (loss) from operations:		(920)	0	$ 0
ASSETS
Total assets:	$ (888,203)	$ (888,203)	$ (804,785)