Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Finite-lived Intangible Assets [Roll Forward]
CDI and CRI Balance, beginning of period	$ 64,187		$ 76,513	$ 64,187	$ 95,524
Accumulated Amortization, beginning of period	(33,950)	$ (30,885)	(32,747)	(27,821)	(42,304)
Amortization	(3,049)	(3,065)	(4,224)	(9,178)	(13,341)
Fully amortized portion	2,190	0	2,811	2,190	20,122
Reduction due to sale of PWEF leasing unit	0	0	0	0	1,363
CDI and CRI Balance, end of period	61,997	64,187	73,702	61,997	73,702
Accumulated Amortization, end of period	(34,809)	(33,950)	(34,160)	(34,809)	(34,160)
Net CDI and CRI, end of period	27,188	30,237	39,542	27,188	39,542
CDI and CRI
Finite-lived Intangible Assets [Roll Forward]
Fully amortized portion	2,190	0	2,811	2,190	20,122
Reduction due to sale of PWEF leasing unit	$ 0	$ 0	$ 0	$ 0	$ (1,700)