Fair Value Measurements (Tables)

6 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

			Fair Value Measurements at Reporting Date Using
			Quoted Prices in				Significant
			Active Markets for		Significant Other		Unobservable
	March 31,		Identical Assets		Observable Inputs		Inputs
Description	2022		(Level 1)		(Level 2)		(Level 3)
Assets:
Cash equivalents	$	764,361	$	764,361	$	—	$	—
Available-for-sale securities		1,076,732		517,457		559,275		—

Foreign exchange contracts		130		—		130		—
Net Investment Hedge		10,673		—		10,673		—
Total Assets	$	1,851,896	$	1,281,818	$	570,078	$	—
Liabilities:
Foreign exchange contracts		734		—		734		—
Total Liabilities	$	734	$	—	$	734	$	—

			Fair Value Measurements at Reporting Date Using
			Quoted Prices in				Significant
			Active Markets for		Significant Other		Unobservable
	September 30,		Identical Assets		Observable Inputs		Inputs
Description	2021		(Level 1)		(Level 2)		(Level 3)
Assets:
Cash equivalents	$	21	$	21	$	—	$	—
Available-for-sale securities		3,679		—		3,679		—
Foreign exchange contracts		153		—		153		—
Total Assets	$	3,853	$	21	$	3,832	$	—
Liabilities:
Foreign exchange contracts		165	$	—		165		—
Acquisition-related contingent consideration		9,400		—		—		9,400
Total Liabilities	$	9,565	$	—	$	165	$	9,400