Summary of Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Foreign Currency Transaction Gain (Loss), before Tax [Abstract]
Foreign currency transaction and remeasurement losses	$ (1,200)	$ (400)	$ (3,200)	$ 400
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract]
Foreign currency translation reclassification adjustments included in income from discontinued operation	$ 16,567		$ 16,567