Supporting Financial Information - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest expense									$ (2,841)	$ (1,512)
Amortization of deferred financing costs									(721)	(982)
Other income (expense), net									121	21
Interest expense, net	$ (781)	$ (813)	$ (906)	$ (941)	$ (1,190)	$ (562)	$ (545)	$ (177)	$ (3,441)	$ (2,473)