Leases - Rental Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Rental Equipment [Abstract]
Rental equipment, primarily wireless recording equipment	$ 97,938	$ 114,783
Accumulated depreciation and impairment	(53,771)	(60,466)
Rental equipment, net	$ 44,167	$ 54,317