Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Tax Credit Carryforward [Line Items]
Valuation allowance	$ 169,526	$ 169,291
Loss before income tax expense (benefit) less income (loss) attributable to noncontrolling interests	(30,900)	$ (128,300)	$ (153,200)
Federal
Tax Credit Carryforward [Line Items]
Operating loss carryforward	397,300
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Operating loss carryforward	442,300
Research and Development | Federal
Tax Credit Carryforward [Line Items]
Tax credit carryforwards	16,300
Research and Development | State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Tax credit carryforwards	16,400
Other State Tax Credit Carryforward | State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Tax credit carryforwards	$ 2,200