Restructuring - Summary of Restructuring Activity (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost And Reserve [Line Items]
Balance at January 1, 2019	$ 30
Charges to expense	865	$ 119
Cash payments	(767)
Balance at September 30, 2019	128
Employee Reduction [Member]
Restructuring Cost And Reserve [Line Items]
Balance at January 1, 2019	30
Charges to expense	865
Cash payments	(767)
Balance at September 30, 2019	$ 128