ORGANIZATION AND BASIS OF PRESENTATION - Contract with Customers (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Revenue from External Customer [Line Items]
Contract assets	$ 95,700	$ 53,200
Contract related liabilities	71,422	71,248
Outstanding gaming chips and slot tickets liability
Revenue from External Customer [Line Items]
Contract related liabilities	11,350	7,968
Loyalty points deferred revenue liability
Revenue from External Customer [Line Items]
Contract related liabilities	39,374	40,968
Patron advances and other liability
Revenue from External Customer [Line Items]
Contract related liabilities	20,698	22,312
Mohegan Sun Pocono
Revenue from External Customer [Line Items]
Contract related liabilities	$ 17,700	$ 18,000

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant