Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Deferred Tax Liabilities, Net	$ 122.4		$ 122.4		$ 75.8
Valuation allowance	$ 0.0		$ 0.0
U.S. federal statutory income tax rate, percent	21.00%	21.00%	21.00%	21.00%
Unrecognized tax benefits	$ 0.0	$ 0.0	$ 0.0	$ 0.0

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

+ References

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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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