Income Taxes - Schedule Of Reconciliation Of Beginning And Ending Amount Of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	$ 42,287	$ 31,672	$ 23,135
Gross increases related to prior period tax positions	8,664	5,129	2,715
Gross decreases related to prior period tax positions	(1,051)	(287)	0
Gross increases related to current period tax positions	9,272	7,756	8,230
Decreases relating to settlements with tax authorities	(3,578)	0	0
Reductions due to lapses of statute of limitations	(3,827)	(1,983)	(2,408)
Balance, end of period	$ 51,767	$ 42,287	$ 31,672

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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