Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Federal corporate tax rate	21.00%	21.00%	35.00%
Deferred tax liability related to foreign earnings	$ 0
Excess tax shortfall (benefit) from exercise of share-based awards	$ (2,100,000)	$ (2,000,000.0)	$ (900,000)
Likelihood percentage of being realized upon ultimate settlement with the relevant tax authority	50.00%
Unrecognized tax benefits	$ 0	0
Changes in unrecognized benefits	0	$ 0	$ 0
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Net operating losses carryforwards	$ 600,000
Net operating losses carryforwards, expiration year	2023

Operating loss carryforwards expiration year.

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Tax benefit likelihood percentage.

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Tax cuts and jobs act of 2017 incomplete accounting accumulated earnings of foreign subsidiary provisional unrecognized deferred tax liability.

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Excess tax shortfall (benefit) from exercise of stock options.

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

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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