Income Taxes - Schedule of Loss Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Pre-tax book loss	$ (53,295)	$ (71,480)
Tax at federal statutory rate	(11,192)	(15,011)
Stock-based compensation	1,060
State taxes	766	49
Foreign rate differential	(871)	(713)
Deferred rate change		(80)
TCJA impact		(7,712)
Other adjustments	(1,707)	1,578
Valuation allowance	12,663	18,148
Total income tax (benefit) provision	$ 719	$ (3,741)

Income tax reconciliation change in deferred rate.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount 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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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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

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