Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Valuation Allowance, Deferred Tax Asset, Change in Amount	$ 1,187
Undistributed Earnings of Foreign Subsidiaries	10,300	$ 11,000
U.S.
Operating Loss Carryforwards	0	2,000
Tax Credit Carryforwards	0	279
State
Operating Loss Carryforwards	76	$ 4,800
Tax Credit Carryforwards	495
Unlimited carryover	54
U.K.
Operating Loss Carryforwards	$ 9,300