Stockholders' Equity - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021
Number of Shares
Outstanding at September 30, 2021 (in shares)	816,717
Granted (in shares)	0
Exercised (in shares)	(9,375)
Canceled (in shares)	0
Outstanding at December 31, 2021 (in shares)	807,342	816,717
Weighted-Average Exercise Price
Outstanding at September 30, 2021 (in dollars per share)	$ 7.42
Granted (in dollars per share)	0
Exercised (in dollars per share)	2.66
Canceled (in dollars per share)
Outstanding at December 31, 2021 (in dollars per share)	$ 7.48	$ 7.42
Options, Additional Disclosures
Outstanding at September 30, 2021, Weighted-Average Remaining Contractual Term (in Years)	5 years 7 months 6 days	5 years 9 months 18 days
Outstanding at December 31, 2021, Weighted-Average Remaining Contractual Term (in Years)	5 years 7 months 6 days	5 years 9 months 18 days
Outstanding at September 30, 2021, Aggregate Intrinsic Value (in thousands)	$ 8,292	$ 9,046
Outstanding at December 31, 2021, Aggregate Intrinsic Value (in thousands)	$ 8,292	$ 9,046
Options, Vested and Expected to Vest
Vested and Expected to Vest at December 31, 2021 (in shares)	807,342
Vested and Expected to Vest at December 31, 2021, Weighted Average Exercise Price (in dollars per share)	$ 7.48
Vested and Expected to Vest at December 31, 2021, Weighted Average Remaining Contractual Term (in Years)	5 years 7 months 6 days
Vested and Expected to Vest at December 31, 2021, Aggregate Intrinsic Value (in thousands)	$ 8,292
Exercisable at December 31, 2021 (in shares)	651,807
Exercisable at December 31, 2021, Weighted Average Exercise Price (in dollars per share)	$ 6.98
Exercisable at December 31, 2021, Weighted Average Remaining Contractual Term (in Years)	5 years 2 months 12 days
Exercisable at December 31, 2021, Aggregate Intrinsic Value (in thousands)	$ 7,023