Fair Value (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Fair Value.
Contingently convertible Series E units liability, Beginning Balance	$ 72,057	$ 66,938
Contingently convertible Series E units liability, Remeasurement included in earnings	1,838	(2,756)
Contingently convertible Series E units liability, Ending Balance	70,219	69,694
Preferred shares derivative liability, Beginning Balance	57,960	28,150
Preferred shares derivative liability, Issuance		1,242
Preferred shares derivative liability, Remeasurement included in earnings	120	(457)
Preferred shares derivative liability, Ending Balance	$ 57,840	$ 29,849