Restructuring - Summary of Changes in Restructuring Liabilities (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Balance at December 31, 2018	$ 1,069
Balance at September 30, 2019	94
Accounting Standards Update 2016-02
Restructuring Cost And Reserve [Line Items]
Effect of the new lease standard adoption	(975)
Employee Termination Benefits
Restructuring Cost And Reserve [Line Items]
Balance at December 31, 2018	94
Balance at September 30, 2019	94
Employee Termination Benefits | Accounting Standards Update 2016-02
Restructuring Cost And Reserve [Line Items]
Effect of the new lease standard adoption	0
Cease-Use Costs
Restructuring Cost And Reserve [Line Items]
Balance at December 31, 2018	975
Balance at September 30, 2019	0
Cease-Use Costs | Accounting Standards Update 2016-02
Restructuring Cost And Reserve [Line Items]
Effect of the new lease standard adoption	$ (975)