Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 38,312	$ 13,368	$ 95,503	$ 66,583
Other comprehensive income (loss):
Foreign currency translation adjustments	(7,890)	(23,784)	17,117	(8,823)
Interest rate caps, net of tax		(80)	175	29
Foreign exchange contracts, net of tax	574	2,038	(1,020)	1,838
Other comprehensive income (loss), net of tax	(7,316)	(21,826)	16,272	(6,956)
Total comprehensive income (loss)	$ 30,996	$ (8,458)	$ 111,775	$ 59,627