Accrued Restructuring (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring and Related Activities [Abstract]
Employee-related restructuring expenses	$ 3,890	$ 1,468	$ 5,463
Facility reductions	392	0	602
Integration-related and other non-recurring expenses	629	2,097	1,039
Non-recurring legal expenses	109	796	779
Fair value adjustments to contingent consideration liability	0	156	(1,740)
Write off of purchased computer software	0	0	2,868
Net gain from sale of OS-9 software assets	0	0	(1,532)
Restructuring and other charges, net	$ 5,020	$ 4,205	$ 7,479