Decrease in deferred tax assets.

No definition available.

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- Definition

Income taxes.

+ References

No definition available.

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- Definition

Increase decrease in income tax provision.

+ References

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Income Taxes [Line Items]
Valuation allowance on deferred tax assets	$ 119,000			$ 119,000		$ 119,000
Income tax provision	$ 6,719,000	$ 6,723,000		$ 10,169,000	$ 10,582,000
Effective income tax rate	26.00%	27.90%		25.80%	27.60%
Federal corporate tax rate			35.00%	21.00%
Tax Cuts and Jobs Act [Member]
Income Taxes [Line Items]
Reduction in beginning deferred tax assets					$ 889,000
Increase in income tax provision					$ 889,000