Other Income (Expense), Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Income and Expenses [Abstract]
Interest and amortization expense	$ (2,537)	$ (2,493)	$ (628)
Sale of New Jersey state tax benefit	0	2,898	2,288
Investment and other income, net	543	457	179
Other income (expense), net	$ (1,994)	$ 862	$ 1,839