Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2038	Dec. 31, 2022
Income Taxes [Line Items]
Tax Cuts and Jobs Act of 2017, income tax expense		$ 24,500,000
Tax Cuts and Jobs Act of 2017, remeasurement of deferred tax assets and liabilities				$ 400,000	$ 41,600,000
Tax Cuts and Jobs Act of 2017, transition tax for accumulated foreign earnings, income tax expense				1,300,000	30,800,000
Tax Cuts and Jobs Act of 2017, valuation allowance against foreign tax credit carryforward			$ (10,000,000.0)	8,000,000.0	35,300,000
SAB 118 Tax Expense	$ 2,900,000			10,000,000.0
Tax Cuts and Jobs Act of 2017, income tax expense related to employee compensation				1,100,000
Foreign tax rate differences benefit in income tax			(13,100,000)	(2,400,000)	14,700,000
Income tax expense reduction due to tax holiday			3,900,000	3,000,000.0	3,500,000
Net tax credit carryforwards			47,100,000
Net operating loss carryforwards			216,639,000
Operating loss carryforwards that will be used in expiration periods			150,500,000
Net tax credit carryforwards that will expire			47,064,000
Net tax credit carry forwards with indefinite carry forward period			5,200,000
Net tax credit carryforwards that expected to be utilized prior to expiry			8,300,000
Net decrease in reserve for uncertain tax positions			200,000
Balance at end of the year of unrecognized tax benefits	6,591,000	$ 6,881,000	6,779,000	6,591,000	$ 6,881,000
Estimate the range of reasonably possible changes to unrecognized tax positions			400,000
Accrued interest expense (income) and penalties of unrecognized tax benefits	$ 0		0	$ 0
Scenario, Forecast
Income Taxes [Line Items]
Net tax credit carryforwards that will expire						$ 39,800,000	$ 2,100,000
Net Operating Loss Carry Forwards Expires In 2018
Income Taxes [Line Items]
Net operating loss carryforwards			6,700,000
Net Operating Loss Carry Forwards Expires Between Two Thousand Twenty And Two Thousand Twenty Two
Income Taxes [Line Items]
Net operating loss carryforwards			22,600,000
Net Operating Loss Carry Forwards Expires Between Two Thousand Twenty Three And Two Thousand Thirty Eight
Income Taxes [Line Items]
Net operating loss carryforwards			142,300,000
Net Operating Loss Carry Forward Indefinite Period
Income Taxes [Line Items]
Net operating loss carryforwards			$ 45,000,000.0