Income Taxes [Line Items]

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- Definition

Operating loss carryforwards expiration year.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Income Taxes [Line Items]
Effective tax rate (ETR) from continuing operations	25.50%	24.70%
Statutory federal tax rate	21.00%
State net operating loss carryforwards			$ 3.1
Domestic Tax Authority [Member] \| 2027-2038 [Member]
Income Taxes [Line Items]
Net operating loss carryforwards			512.4
State and Local Jurisdiction [Member] \| 2021-2040 [Member]
Income Taxes [Line Items]
Net operating loss carryforwards			$ 223.9
Minimum [Member] \| Domestic Tax Authority [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration year			2027
Minimum [Member] \| State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration year			2021
Maximum [Member] \| Domestic Tax Authority [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration year			2038
Maximum [Member] \| State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration year			2040