Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
U.S. statutory income tax rate	35.00%	35.00%	35.00%
State tax, net of U.S. federal tax benefit	2.60%	2.50%	2.90%
Non-U.S. income taxes	(0.10%)	(0.30%)	1.20%
Nondeductible incentive stock option expense	0.80%	0.20%	(0.40%)
Research and development credit	(0.60%)	(2.40%)	(0.70%)
Change in deferred tax measurement rate	0.00%	0.10%	0.20%
Change in uncertain tax positions	1.10%	1.50%	2.20%
Expiration of capital loss carryforward	0.00%	0.00%	26.90%
Valuation allowance	(5.80%)	(4.10%)	(267.60%)
Other	0.00%	0.10%	0.20%
Effective income tax rate for continuing operations	33.00%	32.60%	(200.10%)
Valuation allowance	$ 888	$ 6,156
Loss and Other Credit Carryforward [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	600
Loss and Other Credit Carryforward [Member] | Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 300