Corporate Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
Federal	$ (9,599)	$ 9,346	$ (3,100)
Foreign	(63)	(63)	67
State and Local	(56)	488	197
Total	(9,718)	9,771	(2,836)
Deferred
Federal	12	0	(8,262)
Foreign	0	0	0
State and Local	20	0	(3,253)
Total	32	0	(11,515)
Federal income tax expense (benefit)	(9,587)	9,346	(11,362)
Foreign income tax expense (benefit)	(63)	(63)	67
State and local income tax expense (benefit)	(36)	488	(3,056)
Income tax expense (benefit)	$ (9,686)	$ 9,771	$ (14,351)