Selected Quarterly Financial Data (Unaudited) - Narrative (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			12 Months Ended			0 Months Ended	3 Months Ended
	Dec. 31, 2014	Jun. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 09, 2014	Sep. 30, 2014
Equity Investments
Gain on sale of equity investment				$ 171,561	$ 66,293	$ 0
Loss on asset impairment	167,100	22,700	124,300	191,490	384,141	242,497
SIR
Equity Investments
Gain on sale of equity investment							$ 171,600	$ 171,800