Restructuring (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring charges	$ 0	$ 622,000
Components of restructuring expenses and reserve
Accrued restructuring, beginning of period	74,000	2,883,000
Employee severance, benefits and related costs	0	809,000
Payments	(74,000)	(1,599,000)
Accrued restructuring, end of period	$ 0	$ 2,093,000