Commitments and Contingencies - Rent (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loss Contingencies [Line Items]
Rent expense	$ 2.9	$ 3.5	$ 6.7
Accrued expenses and other current liabilities
Loss Contingencies [Line Items]
Deferred rent liability, current	$ 1.6	$ 1.6