Long-Term Debt - Schedule of Long-term Debt (Details) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Line of Credit \| Senior Secured Credit Facility - Term Loan A
Debt Instrument [Line Items]
Debt issuance costs	$ 2,588	$ 4,236
Line of Credit \| Senior Secured Credit Facility - Term Loan B
Debt Instrument [Line Items]
Debt issuance costs	14,057	16,925
Line of Credit \| MGE Niagara Resorts Credit Facility - Term Loan
Debt Instrument [Line Items]
Debt issuance costs	813	1,002
Line of Credit \| Mohegan Expo Credit Facility
Debt Instrument [Line Items]
Debt issuance costs	665	925
Line of Credit \| Guaranteed Credit Facility
Debt Instrument [Line Items]
Debt issuance costs	955	1,191
Senior Unsecured Notes \| 2016 7 7/8% Senior Unsecured Notes
Debt Instrument [Line Items]
Debt issuance costs	$ 8,382	$ 9,565
Note stated interest rate	7.875%	7.875%
Notes Payable to Banks \| Redemption Note Payable
Debt Instrument [Line Items]
Debt issuance costs	$ 17,738	$ 23,905

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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