Income Taxes (Details 3) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013
Income Taxes
Federal net operating loss carryforwards	$ 161.7
Increase in valuation allowance	$ 10.4
Effective tax rate (as a percent)	0.00%	0.00%	0.00%
Accrued interest or penalties related to uncertain tax positions	$ 0.0	$ 0.0
Income tax returns currently under examination \| item	0

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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