Stockholders Equity - Share Repurchase Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Jul. 28, 2021
Stockholder's Equity
Repurchases of common stock from share repurchase plan			142,392	112,978
Repurchases of common stock to satisfy employee payroll taxes		37,002	37,002	23,751	5,440
Aggregate purchase price of shares repurchased to satisfy employee payroll taxes		$ 1,534
Share Repurchase Plan
Stockholder's Equity
Available cash to purchase shares						$ 20,000
Repurchases of common stock from share repurchase plan	142,392	112,978
Repurchase of common stock price (dollars per share)	$ 40.09	$ 37.57
Aggregate purchase price of shares repurchased from share repurchase plan	$ 5,709	$ 4,245