Investment Securities, Available-for-sale Securities, Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 421,807	$ 573,432
Gross Unrealized Gains	11,105	2,811
Gross Unrealized Losses	210	2,420
Fair Value	432,702	573,823
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	0	104,895
Gross Unrealized Gains	0	36
Gross Unrealized Losses	0	419
Fair Value	0	104,512
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	110	160
Gross Unrealized Gains	1	2
Gross Unrealized Losses	0	0
Fair Value	111	162
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	323,203	388,537
Gross Unrealized Gains	8,279	2,406
Gross Unrealized Losses	13	1,426
Fair Value	331,469	389,517
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	53,094	30,164
Gross Unrealized Gains	1,542	367
Gross Unrealized Losses	197	95
Fair Value	54,439	30,436
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	44,715	48,991
Gross Unrealized Gains	1,283	0
Gross Unrealized Losses	0	480
Fair Value	45,998	48,511
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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