Income Taxes - Summary of Changes in Deferred Tax Asset Valuation Allowance (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 88,596	$ 68,661	$ 88,453
Balance at End of Year	106,438	88,596	68,661
Valuation Allowance of Deferred Tax Assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Charged to Costs and Expenses	13,784	19,935	17,898
Write-offs	$ 4,058	$ 0	$ (37,690)