INCOME TAXES - Reconciliation of the Change in Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at October 1,	$ 14,905	$ 4,773
Gross increases - tax positions in prior periods	0	3
Gross decreases - current period effect of tax positions	(28)	(280)
Gross increases - current period effect of tax positions	1,067	10,537
Expiration of statute of limitations for assessments	(185)	(128)
Unrecognized tax benefits at September 30,	$ 15,759	$ 14,905

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 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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