Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	$ 1,854	$ 1,219	$ 1,046
Increases related to tax positions taken during the current period	240	180	179
Increases related to tax positions taken during a prior period	609	455	338
Decreases related to expiration of statute of limitations	0	0	0
Decreases related to settlement with taxing authorities	0	0	(344)
Balance at end of period	$ 2,703	$ 1,854	$ 1,219

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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- Definition

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

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- Definition

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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