CONSOLIDATED STATEMENTS OF CHANGES IN CAPITAL - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	$ (133,242)	$ (67,989)	$ 137,433
Net income (loss)	75,196	7,353	(162,016)
Foreign currency translation adjustment	(86,081)	(929)	7,303
Other	2,343	(7,551)	(48)
Total capital at end of period	(213,899)	(133,242)	(67,989)
Retained Earnings (Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	(133,087)	(75,692)	137,124
Net income (loss)	74,651	6,731	(162,155)
Total capital at end of period	(130,551)	(133,087)	(75,692)
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	0	0	0
Total capital at end of period	0	0	0
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	(2,065)	223	(6,633)
Foreign currency translation adjustment	(86,081)	(2,305)	6,904
Other		17	(48)
Total capital at end of period	(88,146)	(2,065)	223
Total Capital Attributable to Mohegan Tribal Gaming Authority
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	(135,152)	(75,469)	130,491
Net income (loss)	74,651	6,731	(162,155)
Foreign currency translation adjustment	(86,081)	(2,305)	6,904
Other		17	(48)
Total capital at end of period	(218,697)	(135,152)	(75,469)
Non-controlling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total capital at beginning of period	1,910	7,480	6,942
Net income (loss)	545	622	139
Foreign currency translation adjustment		1,376	399
Other	2,343	(7,568)
Total capital at end of period	4,798	1,910	7,480
Mohegan Tribe
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from Mohegan Tribe	325	2,814	10,000
Distributions to Mohegan Tribe	(71,400)	(66,000)	(60,000)
Mohegan Tribe | Retained Earnings (Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from Mohegan Tribe			10,000
Distributions to Mohegan Tribe	(71,075)	(63,186)	(60,000)
Mohegan Tribe | Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from Mohegan Tribe	325	2,814
Distributions to Mohegan Tribe	(325)	(2,814)
Mohegan Tribe | Total Capital Attributable to Mohegan Tribal Gaming Authority
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from Mohegan Tribe	325	2,814	10,000
Distributions to Mohegan Tribe	(71,400)	(66,000)	(60,000)
Salishan Company, LLC
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distributions to Salishan Company, LLC	(1,040)	(940)	(661)
Salishan Company, LLC | Retained Earnings (Deficit)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distributions to Salishan Company, LLC	(1,040)	(940)	(661)
Salishan Company, LLC | Total Capital Attributable to Mohegan Tribal Gaming Authority
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Distributions to Salishan Company, LLC	$ (1,040)	$ (940)	$ (661)