Income Taxes - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) subsidiary	Mar. 31, 2019 USD ($)	Dec. 31, 2019 subsidiary
Income Tax Disclosure [Abstract]
Pre-tax losses	$ 29,044	$ 22,045
Benefit from income taxes	$ 122	$ 85
Percentage of annual research and development credit for cash	65.00%	65.00%
Number of foreign subsidiaries \| subsidiary	0		0

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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