Corporate Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current
Federal	$ 9,346	$ (3,100)	$ 12,454
Foreign	(63)	67	183
State and Local	488	197	266
Total	9,771	(2,836)	12,903
Deferred
Federal	0	(8,262)	14,684
Foreign	0	0	0
State and Local	0	(3,253)	25,024
Total	0	(11,515)	39,708
Federal income tax expense (benefit)	9,346	(11,362)	27,138
Foreign income tax expense (benefit)	(63)	67	183
State and local income tax expense (benefit)	488	(3,056)	25,290
Income tax expense (benefit)	$ 9,771	$ (14,351)	$ 52,611