Debt - Credit Agreement - Additional Information (Details) - USD ($)	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Feb. 01, 2022	Sep. 30, 2021	Feb. 13, 2020
Debt Instrument [Line Items]
Credit facility amount					$ 1,000,000,000
Voting interest in domestic subsidiaries pledged against credit facility	100.00%
Voting interest in foreign subsidiaries pledged against credit facility	65.00%
Leverage ratio, actual	2.23
Senior debt leverage ratio, actual	0.71
Fixed charge coverage ratio, actual	14.02
Periodic interest payment	$ 2,400,000	$ 700,000
Interest rate during period	3.20%	3.80%
Foreign Subsidiary | Subsequent Event
Debt Instrument [Line Items]
Long-term portion of long term debt			$ 0
Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity expansion amount					$ 500,000,000
Credit facility maturity date	Feb. 13, 2025
Basis spread on Federal Reserve Bank of New York (FRBNY) rate	0.50%
Basis spread on adjusted LIBOR	1.00%
Investment limit in foreign subsidiaries	$ 100,000,000
Cash investment limit for acquisition of business	$ 200,000,000
Total leverage ratio	4.50
Senior secured leverage ratio	3.00
Minimum fixed charge coverage ratio allowed under debt covenant	3.00
Line of Credit | Long-term Debt
Debt Instrument [Line Items]
Long-term portion of long term debt	$ 450,000,000			$ 450,000,000
Annual rate for borrowing outstanding	1.69%
Line of Credit | Minimum
Debt Instrument [Line Items]
Variable interest rate, length of time between updates	30 days
Credit facility commitment fees percentage	0.175%
Line of Credit | Minimum | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Line of Credit | Minimum | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Line of Credit | Maximum
Debt Instrument [Line Items]
Variable interest rate, length of time between updates	180 days
Credit facility commitment fees percentage	0.30%
Line of Credit | Maximum | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Line of Credit | Maximum | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%