Income Taxes - Provision for income taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal									$ 279	$ 2,358	$ 928
State and local									(3,072)	(8,769)	(4,124)
Total current income tax provision									(2,793)	(6,411)	(3,196)
Deferred federal									(26,005)	6,402	(7,797)
Deferred other									(3,957)	(102)	(914)
Total deferred income tax provision									(29,962)	6,300	(8,711)
Benefit for income taxes	$ (17,094)	$ 1,197	$ (4,099)	$ (6,539)	$ (5,023)	$ 2,755	$ (1,591)	$ (2,472)	$ (32,755)	$ (111)	$ (11,907)