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Long-Term Development Project, Receivables, Term

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Long-term Development Project, Term of Management Agreement

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Noncontrolling Interest, Redemption Liability At Fair Value Disclosure

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[Line Items] for Schedule of Long-term Development Projects [Table]

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Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of account and note receivables due from other than related parties.

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Area of a real estate property.

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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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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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The value of notes retired (or transferred to another entity) in noncash investing or financing transactions.

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The cash inflow associated with principal collections from a borrowing supported by a written promise to pay an obligation.

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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Redemption value, as if currently redeemable, of redeemable noncontrolling interest for other shares, units or ownership interests classified as temporary equity and the election has been made to accrete changes in redemption value to the earliest redemption date.

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MOHEGAN VENTURES-NORTHWEST, LLC (COWLITZ PROJECT) (Details) $ in Thousands		1 Months Ended				9 Months Ended	12 Months Ended
	Dec. 04, 2017 USD ($)	Apr. 30, 2017	Apr. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2015 USD ($)	Jun. 30, 2017	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2006 a
Schedule of Long-term Development Projects [Line Items]
Redemption liability							$ 72,351	$ 0
Total assets							2,235,681	2,227,962
Total liabilities							$ 1,926,512	1,865,310
Salishan-Mohegan \| Cowlitz Tribe
Schedule of Long-term Development Projects [Line Items]
Accounts and Notes Receivable, Net			$ 344
Salishan-Mohegan Development Company, LLC \| Mohegan Tribe
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)						10.85%
Salishan-Mohegan Development Company, LLC \| Mohegan Ventures-Northwest
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)						49.15%
Salishan-Mohegan \| Mohegan Tribe
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)		18.08%					18.08%
Salishan-Mohegan \| Mohegan Ventures-Northwest
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)		81.92%					81.92%
Salishan-Mohegan \| Salishan Company, LLC
Schedule of Long-term Development Projects [Line Items]
Initial redemption liability							$ 68,511
Redemption liability							72,351	0
Cowlitz Tribal Gaming Authority \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Accounts Receivable, Related Parties							92,300	81,900
Allowance For Doubtful Accounts Receivable, Related Parties							9,200	16,400
Total assets							90,000	70,800
Total liabilities							$ 147,000	$ 67,500
Cowlitz Project \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Term of management agreement							7 years
Proceeds from Collection of Notes Receivable				$ 19,400
Long-Term Development Project, Receivables, Term				7 years
Long-Term Development Project, Receivables, Stated Interest Rate				12.74%
Cowlitz Project \| Salishan-Mohegan \| Cowlitz Tribe \| Land
Schedule of Long-term Development Projects [Line Items]
Land transferred to CTGA					$ 20,000
Cowlitz Project \| Salishan-Mohegan \| Cowlitz Tribal Gaming Authority (CTGA)
Schedule of Long-term Development Projects [Line Items]
Reduction in notes payable					$ 342
Cowlitz Project \| Salishan-Mohegan \| Cowlitz Tribal Gaming Authority (CTGA) \| Land
Schedule of Long-term Development Projects [Line Items]
Land transferred to CTGA			$ 686
Cowlitz Project \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Development fee (as a percent)							3.00%
Area of land purchased (in acres) \| a									156
Management fee							24.00%
Cowlitz Project \| Mohegan Ventures-Northwest \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)							49.15%
Cowlitz Project \| Salishan Company, LLC \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)							40.00%
Cowlitz Project \| Mohegan Tribe \| Salishan-Mohegan
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)							10.85%
Non-controlling Interests \| Salishan-Mohegan Development Company, LLC
Schedule of Long-term Development Projects [Line Items]
Membership or limited partnership interest (as a percent)						40.00%
Subsequent Event \| Salishan-Mohegan \| Salishan Company, LLC
Schedule of Long-term Development Projects [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	$ 114,800