Provision (Benefit) for Income Taxes (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Summary of consolidated income tax provision (benefit)
Current income taxes	$ (410)	$ 314	$ (12)
Deferred income taxes	(80,133)	(150,357)	2,652
Income tax provision (benefit)	$ (80,543)	$ (150,043)	$ 2,640