Investment Securities, Available-for-sale Securities, Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 573,432	$ 515,531
Gross Unrealized Gains	2,811	58
Gross Unrealized Losses	2,420	14,126
Fair Value	573,823	501,463
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	104,895	154,868
Gross Unrealized Gains	36	0
Gross Unrealized Losses	419	2,708
Fair Value	104,512	152,160
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	160	168
Gross Unrealized Gains	2	5
Gross Unrealized Losses	0	0
Fair Value	162	173
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	388,537	271,386
Gross Unrealized Gains	2,406	53
Gross Unrealized Losses	1,426	9,407
Fair Value	389,517	262,032
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	30,164	30,048
Gross Unrealized Gains	367	0
Gross Unrealized Losses	95	110
Fair Value	30,436	29,938
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	48,991	58,376
Gross Unrealized Gains	0	0
Gross Unrealized Losses	480	1,901
Fair Value	48,511	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	0	0
Fair Value	$ 685	$ 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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of 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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-Publisher FASB
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