LONG-TERM DEBT - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Debt Schedule [Abstract]
Long-term debt	$ 1,809,332	$ 1,814,155
Less: current portion of long-term debt	(73,865)	(73,232)
Long-term debt, net of current portion	1,735,467	1,740,923
Credit Facility \| Senior Secured Credit Facility - Revolving
Debt Schedule [Abstract]
Long-term debt	66,000	66,000
Credit Facility \| Senior Secured Credit Facility - Term Loan A
Debt Schedule [Abstract]
Long-term debt	295,424	311,466
Discount and debt issuance costs	6,016	6,661
Credit Facility \| Senior Secured Credit Facility - Term Loan B
Debt Schedule [Abstract]
Long-term debt	809,160	810,430
Discount and debt issuance costs	19,670	20,571
Credit Facility \| Mohegan Expo Credit Facility
Debt Schedule [Abstract]
Long-term debt	30,935	31,980
Discount and debt issuance costs	1,219	1,319
Credit Facility \| Guaranteed Credit Facility
Debt Schedule [Abstract]
Long-term debt	33,568	22,403
Discount and debt issuance costs	1,432	1,262
Senior Unsecured Notes \| 2016 7 7/8% Senior Unsecured Notes
Debt Schedule [Abstract]
Long-term debt	489,323	488,967
Discount and debt issuance costs	$ 10,677	11,033
Note stated interest rate	7.875%
Note Payable \| Redemption Note Payable
Debt Schedule [Abstract]
Long-term debt	$ 83,558	81,165
Discount and debt issuance costs	31,242	33,635
Other
Debt Schedule [Abstract]
Long-term debt	$ 1,364	$ 1,744

Long-term Debt, Including Due to Related Parties, Current

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Long-term Debt, Including Due to Related Parties, Noncurrent

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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