Restructuring and Related Charges (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
2015 Restructuring Plan [Member]
Restructuring Reserve [Roll Forward]
Accrued restructuring and related charges liability as of period start	$ 4,305
Payments	(1,126)
Accrued restructuring and related charges liability as of period end	3,179
Restructuring Cost [Abstract]
Restructuring charges incurred	24,000
2016 Restructuring Plan [Member]
Restructuring Reserve [Roll Forward]
Accrued restructuring and related charges liability as of period start	3,899
Restructuring charges	810
Payments	(3,160)
Adjustments	(141)	[1]
Accrued restructuring and related charges liability as of period end	1,408
Restructuring Cost [Abstract]
Restructuring charges incurred	$ 5,600

[1] Adjustments consist primarily of actual employee tax and benefit amounts differing from previous estimates.