Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Long-term debt	$ 2,040,840	$ 1,909,157
Less: current portion of long-term debt	(77,829)	(76,909)
Long-term debt, net of current portion	1,963,011	1,832,248
Line of Credit \| Senior Secured Credit Facility - Revolving
Debt Instrument [Line Items]
Long-term debt	247,000	102,000
Line of Credit \| Senior Secured Credit Facility - Term Loan A
Debt Instrument [Line Items]
Long-term debt	237,664	263,829
Line of Credit \| Senior Secured Credit Facility - Term Loan B
Debt Instrument [Line Items]
Long-term debt	801,752	805,394
Line of Credit \| 2016 7 7/8% Senior Unsecured Notes
Debt Instrument [Line Items]
Long-term debt	491,618	490,435
Line of Credit \| MGE Niagara Resorts Credit Facility - Revolving
Debt Instrument [Line Items]
Long-term debt	25,655	0
Line of Credit \| MGE Niagara Resorts Credit Facility - Term Loan
Debt Instrument [Line Items]
Long-term debt	68,822	73,564
Line of Credit \| Mohegan Expo Credit Facility
Debt Instrument [Line Items]
Long-term debt	28,368	29,357
Line of Credit \| Guaranteed Credit Facility
Debt Instrument [Line Items]
Long-term debt	30,108	31,840
Convertible Debenture \| MGE Niagara Resorts Convertible Debentures
Debt Instrument [Line Items]
Long-term debt	29,320	30,204
Notes Payable to Banks \| Redemption Note Payable
Debt Instrument [Line Items]
Long-term debt	76,629	81,329
Senior Unsecured Notes \| Other
Debt Instrument [Line Items]
Long-term debt	$ 3,904	$ 1,205

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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.

+ References

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)(3)
-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 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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.

+ References

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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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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