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Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended		12 Months Ended
	Nov. 01, 2013	Dec. 03, 2013	Dec. 31, 2013	Dec. 31, 2014	Jun. 26, 2013
Fair value of financial instruments
Assets recorded at fair value				$ 0us-gaap_AssetsFairValueDisclosure
Liabilities recorded at fair value				$ 0us-gaap_LiabilitiesFairValueDisclosure
Reverse Stock Split and Conversion of Preferred Stock
Reverse stock split ratio	3.1
Series A-1 Convertible Preferred Stock
Reverse Stock Split and Conversion of Preferred Stock
Conversion of Stock, Shares Converted		49,671,392	(49,671,392)
Exchange of Series A-1 and A-2 preferred for common stock (in shares)		16,022,915			5,561,006
Series A-2 Convertible Preferred Stock
Reverse Stock Split and Conversion of Preferred Stock
Conversion of Stock, Shares Converted		1,851,814	(1,851,814)
Exchange of Series A-1 and A-2 preferred for common stock (in shares)		597,359			1,851,814