Commitments and Contingencies Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Restructuring expenses	$ 119	$ 229	$ 567	$ 693
Restructuring reserve	736	209	736	209	$ 1,630	$ 492
Employee Severance [Member]
Loss Contingencies [Line Items]
Restructuring expenses	$ 100	$ 200	$ 600	$ 700