Workforce Reductions Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Reserve [Roll Forward]
Restructuring Reserve	$ 1,485	$ 1,530	$ 1,798
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges	2,517	2,336
Payments for separation benefits	(4,289)	$ (2,604)
Acquisition of Business [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 1,727