Investment Securities, Amortized Cost, Fair Values, and Unrealized Gains and Losses of Securities (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		$ 352,877	$ 368,109	$ 339,720
Gross unrealized gains		5,981	2,842	5,320
Gross unrealized losses		1	1,814	312
Fair/Book value		358,857	369,137	344,728
Book values, estimated fair values and unrealized gains and losses of investments classified as held-to-maturity [Abstract]
Book value		58,905	61,396	66,257
Gross unrealized gains		1,549	993	658
Gross unrealized losses		0	1	26
Fair value		60,454	62,388	66,889
Government Agency & Government-Sponsored Entities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		83,129	33,536	41,448
Gross unrealized gains		165	134	65
Gross unrealized losses		1	419	0
Fair/Book value		83,293	33,251	41,513
US Treasury Notes [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		85,470	73,048	30,069
Gross unrealized gains		211	0	231
Gross unrealized losses		0	164	0
Fair/Book value		85,681	72,884	30,300
Mortgage Backed Securities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost	[1]	183,268	261,016	251,483
Gross unrealized gains	[1]	5,605	2,708	5,024
Gross unrealized losses	[1]	0	1,231	312
Fair/Book value	[1]	188,873	262,493	256,195
Corporate Securities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost				16,235
Gross unrealized gains				0
Gross unrealized losses				0
Fair/Book value				16,235
Other [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		1,010	509	485
Gross unrealized gains		0	0	0
Gross unrealized losses		0	0	0
Fair/Book value		1,010	509	485
Obligations of States and Political Subdivisions [Member]
Book values, estimated fair values and unrealized gains and losses of investments classified as held-to-maturity [Abstract]
Book value		58,905	61,396	64,134
Gross unrealized gains		1,549	993	658
Gross unrealized losses		0	1	26
Fair value		$ 60,454	$ 62,388	64,766
Other [Member]
Book values, estimated fair values and unrealized gains and losses of investments classified as held-to-maturity [Abstract]
Book value				2,123
Gross unrealized gains				0
Gross unrealized losses				0
Fair value				$ 2,123

[1] All Mortgage Backed Securities consist of securities collateralized by residential real estate and were issued by an agency or government sponsored entity of the U.S. government.