Leases - Impact of Adoption of Standard in Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Oct. 01, 2019	Sep. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating leases right-of-use assets	$ 22,427
Deferred rent liability - short-term			$ 44
Operating lease liabilities - current	2,045
Deferred rent liability - long-term			276
Unamortized tenant improvement allowance			297
Operating lease liabilities - long-term	21,620
Accumulated deficit	$ (32,443)		$ (39,555)
ASC 842 Adjustments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating leases right-of-use assets		$ 17,398
Deferred rent liability - short-term		(44)
Operating lease liabilities - current		3,645
Deferred rent liability - long-term		(276)
Unamortized tenant improvement allowance		(297)
Operating lease liabilities - long-term		14,372
Accumulated deficit		(2)
October 1, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating leases right-of-use assets		17,398
Deferred rent liability - short-term		0
Operating lease liabilities - current		3,645
Deferred rent liability - long-term		0
Unamortized tenant improvement allowance		0
Operating lease liabilities - long-term		14,372
Accumulated deficit		$ (39,557)