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

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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LONG-TERM DEBT - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jan. 26, 2021	Sep. 30, 2020
Debt Schedule [Abstract]
Long-term debt	$ 2,023,084		$ 1,970,010
Less: current portion of long-term debt	(49,555)		(75,355)
Long-term debt, net of current portion	1,973,529		1,894,655
Credit Facility \| New Senior Secured Credit Facility - Revolving
Debt Schedule [Abstract]
Long-term debt	107,000		0
Credit Facility \| Line of Credit
Debt Schedule [Abstract]
Long-term debt	16,015		0
Credit Facility \| Prior Senior Secured Credit Facility - Revolving
Debt Schedule [Abstract]
Long-term debt	0		197,000
Credit Facility \| Prior Senior Secured Credit Facility - Term Loan A
Debt Schedule [Abstract]
Long-term debt	0		227,710
Debt issuance costs			4,199
Credit Facility \| Senior Secured Credit Facility - Term Loan B
Debt Schedule [Abstract]
Long-term debt	0		792,829
Debt issuance costs			20,809
Credit Facility \| MGE Niagara Resorts Credit Facility - Revolving
Debt Schedule [Abstract]
Long-term debt	27,794		26,187
Credit Facility \| MGE Niagara Credit Facility - Term Loan
Debt Schedule [Abstract]
Long-term debt	71,618		69,297
Debt issuance costs	844		847
Credit Facility \| Mohegan Expo Credit Facility
Debt Schedule [Abstract]
Long-term debt	26,725		27,750
Debt issuance costs	434		658
Credit Facility \| Guaranteed Credit Facility
Debt Schedule [Abstract]
Long-term debt	28,369		29,529
Debt issuance costs	725		877
Credit Facility \| Mohegan Tribe Subordinated Loan
Debt Schedule [Abstract]
Long-term debt	0		5,000
Senior Notes \| 2021 Senior Unsecured Notes
Debt Schedule [Abstract]
Long-term debt	1,156,117		0
Debt issuance costs	$ 18,883
Note stated interest rate	8.00%	8.00%
Senior Notes \| 2016 7 7/8% Senior Unsecured Notes
Debt Schedule [Abstract]
Long-term debt	$ 492,691		491,821
Debt issuance costs	$ 7,309		8,179
Note stated interest rate	7.875%
Convertible Debenture \| MGE Niagara Resorts Convertible Debenture
Debt Schedule [Abstract]
Long-term debt	$ 31,764		29,928
Note Payable to Banks \| Redemption Note Payable
Debt Schedule [Abstract]
Long-term debt	61,330		69,099
Debt issuance costs	11,990		15,701
Other \| Other
Debt Schedule [Abstract]
Long-term debt	$ 3,661		$ 3,860