Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of Unrecognized Tax Benefits
Beginning balance		$ 6,530	$ 3,091	$ 6,530	$ 6,058
Increase for tax positions taken during a prior period			0	963	0
Increase for tax positions taken during the current period			0	0	472
Decrease for tax positions as a result of the lapse of the statute of limitations	$ (3,300)	$ (1,600)	(1,656)	(4,402)	0
Ending balance			$ 1,435	$ 3,091	$ 6,530

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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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.

+ References

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

+ References

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

+ References

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