Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring, expected cost	$ 11,300		$ 11,300
Restructuring Reserve [Roll Forward]
Accrual, beginning balance			2,754
Restructuring costs	98	$ 498	235	$ 8,612	$ 11,100
Utilization			(2,666)
Accrual, ending balance	$ 323		$ 323		$ 2,754