Investment Securities, Securities Available-for-Sale (Details) - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		$ 484,348	$ 499,639	$ 457,812
Gross unrealized gains		4,000	1,208	362
Gross unrealized losses		255	5,451	8,000
Fair/Book value		488,093	495,396	450,174
Government Agency & Government-Sponsored Entities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		3,009	3,033	3,056
Gross unrealized gains		5	6	15
Gross unrealized losses		0	0	0
Fair/Book value		3,014	3,039	3,071
US Treasury Notes [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		174,688	164,672	139,689
Gross unrealized gains		245	0	2
Gross unrealized losses		25	158	416
Fair/Book value		174,908	164,514	139,275
US Govt SBA [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		13,289	15,601	18,583
Gross unrealized gains		23	6	8
Gross unrealized losses		114	160	188
Fair/Book value		13,198	15,447	18,403
Mortgage Backed Securities [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost	[1]	288,550	310,982	293,473
Gross unrealized gains	[1]	3,727	1,196	337
Gross unrealized losses	[1]	116	5,133	7,396
Fair/Book value	[1]	292,161	307,045	286,414
Other [Member]
Amortized cost, fair values, and unrealized gains and losses of securities available-for-sale [Abstract]
Amortized cost		4,812	5,351	3,011
Gross unrealized gains		0	0	0
Gross unrealized losses		0	0	0
Fair/Book value		$ 4,812	$ 5,351	$ 3,011

[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.