Restructuring Charges Restructuring and Related Activities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Reserve [Roll Forward]
Restructuring Reserve	$ 3,400
Restructuring Reserve	0	$ 3,400
2015 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost	254	4,582
Reversal of deferred rent liabilities	0	7,273
Deferred rent liabilities	0	0
Restructuring Reserve [Roll Forward]
Restructuring Reserve	3,400
Payments	(3,654)	(1,182)
Restructuring Reserve	0	3,400
2014 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost		371	$ 3,514
Employee termination costs | 2014 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost		(22)	1,962
Facility closure costs | 2015 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost	0	495
Restructuring Reserve [Roll Forward]
Restructuring Reserve	0
Payments	0	(495)
Restructuring Reserve	0	0
Asset impairment | 2015 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost	0	4,931
Restructuring Reserve [Roll Forward]
Restructuring Reserve	0
Payments	0	(4,931)
Restructuring Reserve	0	0
Asset impairment | 2014 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost		0	1,552
Other exit costs | 2015 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost	254	6,429
Restructuring Reserve [Roll Forward]
Restructuring Reserve	3,400
Payments	(3,654)	(3,029)
Restructuring Reserve	$ 0	3,400
Other exit costs | 2014 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Recognized cost		$ 393	$ 0