MOHEGAN VENTURES-NORTHWEST, LLC (COWLITZ PROJECT) - Reconciliation of development fees (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2017 USD ($)
Development Fees [Roll Forward]
Beginning balance	$ 4,925
Fees earned, including interest receivable	7,340	[1]
Payments received	(8,757)
Ending balance	$ 3,508

[1] Primarily recorded within retail, entertainment and other revenues in the accompanying consolidated statements of income and comprehensive income.