Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Income Tax [Abstract]
Deferred Tax Liabilities, Net	$ 21.0
Deferred Tax Assets, Net		$ 19.8
Valuation allowance	$ 0.0
U.S. federal statutory income tax rate, percent	21.00%
Unrecognized tax benefits	$ 0.0

Income Tax [Abstract]

No definition available.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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

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Amount of unrecognized tax benefits.

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