Income Taxes [Line Items]

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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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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

Description of events or transactions pertaining to income taxes classified as other.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount of reasonable estimate for income tax benefit for which accounting for tax effect for remeasurement of deferred tax liability from change in tax rate is incomplete pursuant to Tax Cuts and Jobs Act.

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Amount of reasonable estimate for income tax expense for which accounting for tax effect from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated is incomplete pursuant to Tax Cuts and Jobs Act.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Income Taxes [Line Items]
Corporate tax rate	21.00%	21.00%	21.00%	21.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability						$ 12,800
Tax cuts and jobs Act, increased tax provision on undistributed and previously untaxed post-1986 earnings and profits of the specified foreign corporation					$ 1,300	3,300
Impact on assets and liabilities due to change in accounting principle						$ (677)
Income tax (benefit) provision	0.70%	27.60%	18.30%	24.60%
Accounting Standards Update 2016-06 [Member] \| Other Assets [Member]
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle							$ 5,700
Accounting Standards Update 2016-06 [Member] \| Deferred tax liablities [Member]
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle							5,000
Accounting Standards Update 2016-06 [Member] \| accumulated deficit [Member]
Income Taxes [Line Items]
Impact on assets and liabilities due to change in accounting principle							$ 700
Latest Tax Year
Income Taxes [Line Items]
Net operating loss and business tax credit carry forwards expiration date					at various dates through December 2038
State
Income Taxes [Line Items]
Business tax credits carry forwards					$ 2,900
United States
Income Taxes [Line Items]
Business tax credits carry forwards					$ 400