Defined contribution plan employer additional discretionary contribution amount.

No definition available.

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- Definition

Income taxes.

+ References

No definition available.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
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- Definition

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

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-Publisher FASB
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-Topic 740
-SubTopic 10
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- Definition

The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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-Publisher FASB
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Income Taxes - Additional Information (Detail) - USD ($)		3 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Taxes [Line Items]
Effective income tax rate			18.30%	26.20%
Net income tax benefit			$ 15,454,000
Contribution made to qualified pension plans	$ 25,000,000
Federal statutory corporate income tax rate			21.00%		35.00%
Qualified Pension Plan [Member]
Income Taxes [Line Items]
Additional contribution made to qualified pension plans		$ 125,000,000
Contribution made to qualified pension plans		$ 150,000,000