Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Operating loss carryforward expiration year	2018 to 2036
Increase in valuation allowance	$ 5.8	$ 15.9
Domestic Tax Authority | Research and development
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	0.4
U.S
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	219.1
Non us
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 0.3