Goodwill and Intangible Assets Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Gross Carrying Value [Abstract]
Goodwill not subject to amortization (effective 1/1/02)	$ 44,767	$ 44,767
Total Goodwill And Intangible Assets, Gross Carrying Value	66,715	66,715
Goodwill and Intangible Assets Accumulated Amortization [Abstract]
Goodwill not subject to amortization (effective 1/1/02)	3,760	3,760
Total Goodwill and Intangible Assets, Accumulated Amortization	17,166	16,711
Intangibles from branch acquisition
Goodwill and Intangible Assets Gross Carrying Value [Abstract]
Finite-Lived Intangible Assets, Gross	3,015	3,015
Goodwill and Intangible Assets Accumulated Amortization [Abstract]
Finite-Lived Intangible Assets, Accumulated Amortization	3,015	3,015
Core Deposits [Member]
Goodwill and Intangible Assets Gross Carrying Value [Abstract]
Finite-Lived Intangible Assets, Gross	15,202	15,202
Goodwill and Intangible Assets Accumulated Amortization [Abstract]
Finite-Lived Intangible Assets, Accumulated Amortization	8,426	8,017
Customer Lists [Member]
Goodwill and Intangible Assets Gross Carrying Value [Abstract]
Finite-Lived Intangible Assets, Gross	3,731	3,731
Goodwill and Intangible Assets Accumulated Amortization [Abstract]
Finite-Lived Intangible Assets, Accumulated Amortization	$ 1,965	$ 1,919