Subsequent Events (Details) (7.50% Convertible Senior Secured Notes due 2019, USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		12 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	May 06, 2015
Subsequent events
Principal amount of the Notes converted	$ 21,407	$ 9,500	$ 53,941
Shares of common stock issued in conversion of Notes and accrued interest thereon	4,000,000
Shares of common stock issued in settlement of the interest make-whole provision	400,000
Subsequent Event
Subsequent events
Principal amount of the Notes converted				$ 1,200
Shares of common stock issued in conversion of Notes and accrued interest thereon				200,000
Shares of common stock issued in settlement of the interest make-whole provision				20,000