Restructuring - (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 1,395	$ 3,375	$ 3,583
2014 Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	30	2,356	3,583
Impairment of Long-Lived Assets Held-for-use			$ 2,056
Cumulative restructuring charges	5,969
2015 Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,365	$ 1,019
Cumulative restructuring charges	$ 2,384