Revenue (Contract Assets and Liabilities) (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Contract liabilities	$ 55,593	$ 36,894	$ 55,883	$ 26,259
Change in Contract with Customer, Asset [Roll Forward]
beginning of period	72,746	80,759
Recognized in current period	206,859	147,593
Reclassified to accounts receivable	179,967	153,964
Foreign currency	(136)	413
end of period	99,502	74,801
Change in Contract with Customer, Liability [Roll Forward]
Recognized in current period	174,518	158,452
Amounts in beginning balance reclassified to revenue	(44,292)	(20,703)
Current period amounts reclassified to revenue	(130,629)	(127,684)
Foreign currency	$ 113	$ 570