Equity Investments - Schedule of Equity Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Equity in earnings of investees	$ 0	$ 0	$ 24,460
SIR
Schedule of Equity Method Investments [Line Items]
Equity in earnings of investees			24,516
AIC
Schedule of Equity Method Investments [Line Items]
Equity in earnings of investees			$ (56)