Investment Securities, Available-for-sale Securities, Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 662,642	$ 515,531
Gross Unrealized Gains	3,199	58
Gross Unrealized Losses	3,082	14,126
Fair Value	662,759	501,463
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	164,889	154,868
Gross Unrealized Gains	58	0
Gross Unrealized Losses	457	2,708
Fair Value	164,490	152,160
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	166	168
Gross Unrealized Gains	3	5
Gross Unrealized Losses	0	0
Fair Value	169	173
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	405,677	271,386
Gross Unrealized Gains	2,701	53
Gross Unrealized Losses	2,212	9,407
Fair Value	406,166	262,032
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	40,209	30,048
Gross Unrealized Gains	349	0
Gross Unrealized Losses	277	110
Fair Value	40,281	29,938
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	51,016	58,376
Gross Unrealized Gains	88	0
Gross Unrealized Losses	134	1,901
Fair Value	50,970	56,475
Other [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	685	685
Gross Unrealized Gains	0	0
Gross Unrealized Losses	2	0
Fair Value	$ 683	$ 685

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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