Income Taxes - Reconciliation Of Federal Statutory Rate To Effective Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%
Increases (decreases) in the rate resulting from:
State income taxes, net of federal income tax impact	6.60%	1.50%
Foreign income taxes	(3.70%)	(0.10%)
Valuation allowance	(1.40%)	0.00%
Research and development credit	9.80%	0.20%
Uncertain tax positions	(5.00%)	0.20%
Tax Reform and other prior period adjustments	0	0.004
Restricted stock vestings	(6.70%)	(0.20%)
Goodwill and intangible asset impairment charges	0.00%	(14.20%)
Other	0.80%	(1.20%)
Effective income tax rate	21.40%	7.60%

Effective Income Tax Rate Reconciliation, Increases (Decrease) [Abstract]

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Effective Income Tax Rate Reconciliation, Share-based Compensation, Restricted Stock Vesting, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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Percentage of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to Tax Cuts and Jobs Act.

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