Investment Securities, Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 589,577	$ 608,521
Gross Unrealized Gains	1,980	469
Gross Unrealized Losses	1,429	7,953
Fair Value	590,128	601,037
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	66,899	86,899
Gross Unrealized Gains	44	19
Gross Unrealized Losses	23	181
Fair Value	66,920	86,737
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	955	1,270
Gross Unrealized Gains	19	20
Gross Unrealized Losses	0	0
Fair Value	974	1,290
Mortgage Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	421,323	416,625
Gross Unrealized Gains	1,821	430
Gross Unrealized Losses	955	5,326
Fair Value	422,189	411,729
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	89,362	92,620
Gross Unrealized Gains	96	0
Gross Unrealized Losses	405	2,204
Fair Value	89,053	90,416
Mortgage Backed Securities and Collateralized Mortgage Obligations-Commercial [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	10,353	10,422
Gross Unrealized Gains	0	0
Gross Unrealized Losses	46	242
Fair Value	10,307	10,180
Other [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	650	650
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	650	650
Debt Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	589,542	608,486
Gross Unrealized Gains	1,980	469
Gross Unrealized Losses	1,429	7,953
Fair Value	590,093	601,002
Equity Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	35	35
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 35	$ 35

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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