Other Comprehensive Income (Loss) - Part 2 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), balance at beginning of period, net	$ 61,981
Accumulated other comprehensive income (loss), balance at end of period, net	781	$ 61,981
Unrealized/Recognized Gains (Losses)
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), balance at beginning of period, net	61,981	174,507
Other comprehensive income (loss) before reclassifications	1,939	12,729
Amounts reclassified from accumulated other comprehensive income (loss)	(63,139)	(125,255)
Accumulated other comprehensive income (loss), balance at end of period, net	$ 781	$ 61,981