Income Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating Loss Carryforwards [Line Items]
Deferred income tax expense (benefit)	$ (2,188,000)	$ 795,000
Deferred tax liabilities	19,777,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Taxable loss	9,900,000	26,600,000
Current income tax benefit	0	$ 0
Operating loss carryforwards	258,600,000
Federal and state research and development tax credits	$ 6,770,000
Expiration date of U.S. federal income tax loss carryforwards	2022
Domestic Tax Authority | Stock Compensation Deductions
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 32,100,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Current income tax benefit	93,000
Operating loss carryforwards	$ 118,800,000