Investment Securities, Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	$ 625,268	$ 682,913
Gross Unrealized Gains	1,751	1,149
Gross Unrealized Losses	2,472	7,303
Fair Value	624,547	676,759
U. S. Government Sponsored Enterprises [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	103,421	78,420
Gross Unrealized Gains	117	2
Gross Unrealized Losses	46	622
Fair Value	103,492	77,800
State and Political Subdivisions [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	1,937	2,232
Gross Unrealized Gains	26	39
Gross Unrealized Losses	0	0
Fair Value	1,963	2,271
Mortgage Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	413,500	486,107
Gross Unrealized Gains	1,607	1,108
Gross Unrealized Losses	1,229	3,655
Fair Value	413,878	483,560
Corporate Bonds [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost		1,500
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		1,500
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	95,233	103,273
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,195	2,777
Fair Value	94,038	100,496
Mortgage Backed Securities and Collateralized Mortgage Obligations-Commercial [Member]
Amortized cost and fair value of the securities available for sale [Abstract]
Amortized Cost	10,492	10,696
Gross Unrealized Gains	1	0
Gross Unrealized Losses	2	249
Fair Value	10,491	10,447
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	625,233	682,878
Gross Unrealized Gains	1,751	1,149
Gross Unrealized Losses	2,472	7,303
Fair Value	624,512	676,724
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)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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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

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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

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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