Investment Securities, Securities Available-for-Sale (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		$ 457,812	$ 482,757	$ 461,231
Gross unrealized gains		362	1,016	1,946
Gross unrealized losses		8,000	2,177	1,310
Fair/Book value		450,174	481,596	461,867
Government Agency & Government-Sponsored Entities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		3,056	3,080	3,103
Gross unrealized gains		15	48	92
Gross unrealized losses		0	0	0
Fair/Book value		3,071	3,128	3,195
US Treasury Notes [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		139,689	144,606	134,689
Gross unrealized gains		2	0	3
Gross unrealized losses		416	442	272
Fair/Book value		139,275	144,164	134,420
US Govt SBA [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		18,583	29,559	32,889
Gross unrealized gains		8	29	30
Gross unrealized losses		188	208	119
Fair/Book value		18,403	29,380	32,800
Mortgage Backed Securities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost	[1]	293,473	302,502	288,121
Gross unrealized gains	[1]	337	939	1,821
Gross unrealized losses	[1]	7,396	1,527	919
Fair/Book value	[1]	286,414	301,914	289,023
Other [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		3,011	3,010	2,429
Gross unrealized gains		0	0	0
Gross unrealized losses		0	0	0
Fair/Book value		$ 3,011	$ 3,010	$ 2,429

[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.