Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current expense: [Abstract]
U.S. federal													$ 1,868	$ 3,536	$ 17,032
State and local													117	311	1,909
Total current income tax expense													1,985	3,847	18,941
Deferred expense (benefit):
U.S. federal													626	(710)	(13,830)
State and local													336	(93)	(1,946)
Total deferred income tax expense (benefit)													962	(803)	(15,776)
Income tax expense	$ 81	$ 1,695	$ 982	$ 189	$ 4,355	$ (1,580)	$ 692	$ (423)	$ 774	$ 676	$ 940	$ 775	2,947	3,044	3,165
Parent Company [Member]
Deferred expense (benefit):
Income tax expense													$ (4,746)	$ 1,090	$ (1,785)