Note 2 - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual) $ in Thousands	6 Months Ended
	Mar. 31, 2020 USD ($)	Oct. 01, 2019 USD ($)	Sep. 30, 2019 USD ($)
Number of Reportable Segments	1
Operating Lease, Right-of-Use Asset	$ 349,437
Operating Lease, Liability, Total	367,768
Retained Earnings (Accumulated Deficit), Ending Balance	111,022		$ 100,923
Accounting Standards Update 2016-01 [Member]
Operating Lease, Right-of-Use Asset		$ 359,600
Operating Lease, Liability, Total		$ 377,800
Capital Lease Obligations, Total	(41,900)
Capital Leases, Balance Sheet, Assets by Major Class, Net, Total	(40,200)
Accounting Standards Update 2016-01 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Retained Earnings (Accumulated Deficit), Ending Balance	$ 1,700