Restructuring Restructuring (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring and Related Activities [Abstract]
Employee severance and related costs	$ 22	$ 1,895	$ 2,341	$ 10,448
Consolidation of leased facilities	(508)	6,657	10,797	8,408
Reversal of previous charges	0	0	0	(178)
Total Restructuring charges	$ (486)	$ 8,552	$ 13,138	$ 18,678

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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