Investment Securities, Available-for-sale Securities, Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 515,531	$ 580,705
Gross Unrealized Gains	58	121
Gross Unrealized Losses	14,126	8,861
Fair Value	501,463	571,965
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	154,868	139,890
Gross Unrealized Gains	0	27
Gross Unrealized Losses	2,708	2,066
Fair Value	152,160	137,851
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	168	515
Gross Unrealized Gains	5	10
Gross Unrealized Losses	0	0
Fair Value	173	525
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	271,386	320,614
Gross Unrealized Gains	53	84
Gross Unrealized Losses	9,407	4,715
Fair Value	262,032	315,983
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	30,048	40,270
Gross Unrealized Gains	0	0
Gross Unrealized Losses	110	108
Fair Value	29,938	40,162
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	58,376	68,921
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,901	1,862
Fair Value	56,475	67,059
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Commercial [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost		9,810
Gross Unrealized Gains		0
Gross Unrealized Losses		110
Fair Value		9,700
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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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