Investment Securities, Available-for-sale Securities, Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 555,946	$ 515,531
Gross Unrealized Gains	317	58
Gross Unrealized Losses	9,797	14,126
Fair Value	546,466	501,463
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	149,870	154,868
Gross Unrealized Gains	26	0
Gross Unrealized Losses	1,604	2,708
Fair Value	148,292	152,160
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	168	168
Gross Unrealized Gains	4	5
Gross Unrealized Losses	0	0
Fair Value	172	173
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	318,864	271,386
Gross Unrealized Gains	198	53
Gross Unrealized Losses	6,116	9,407
Fair Value	312,946	262,032
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	30,299	30,048
Gross Unrealized Gains	89	0
Gross Unrealized Losses	130	110
Fair Value	30,258	29,938
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	56,060	58,376
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,947	1,901
Fair Value	54,113	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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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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
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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