Restructuring Costs - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 4,468	$ 2,594	$ 2,369
Restructuring liability		$ 977	$ 2,338	$ 2,551
Forecast
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 300