Revenue Recognition - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 32,473	$ 25,976
Deposits revenue
Disaggregation of Revenue [Line Items]
Total revenue	19,052	15,616
Identity verification revenue
Disaggregation of Revenue [Line Items]
Total revenue	13,421	10,360
Transferred at Point in Time | Deposits software and hardware
Disaggregation of Revenue [Line Items]
Total revenue	13,630	10,755
Transferred at Point in Time | Identity verification software and hardware
Disaggregation of Revenue [Line Items]
Total revenue	1,815	1,548
Transferred over Time | Deposits services and other
Disaggregation of Revenue [Line Items]
Total revenue	5,422	4,861
Transferred over Time | Identity verification services and other
Disaggregation of Revenue [Line Items]
Total revenue	$ 11,606	$ 8,812