Fair Value (Level 3 assets and liabilities measured at fair value) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Impaired Loans - Covered [Member]
Impaired loans - covered	$ 4,464	$ 5,220
Valuation technique	Appraised value; PV of expected cash flows	Appraised value; PV of expected cash flows
Significant unobservable inputs	Discounts to reflect current market conditions, ultimate collectability, and estimated costs to sell	Discounts to reflect current market conditions, ultimate collectability, and estimated costs to sell
General range of significant input values, minimum	0.00%	0.00%
General range of significant input values, maximum	10.00%	10.00%
Impaired Loans - Non - Covered [Member]
Impaired loans - non-covered	21,158	20,512
Valuation technique	Appraised value; PV of expected cash flows	Appraised value; PV of expected cash flows
Significant unobservable inputs	Discounts to reflect current market conditions, ultimate collectability, and estimated costs to sell	Discounts to reflect current market conditions, ultimate collectability, and estimated costs to sell
General range of significant input values, minimum	0.00%	0.00%
General range of significant input values, maximum	10.00%	10.00%
Foreclosed Real Estate - Covered [Member]
Other real estate - covered	2,055	2,350
Valuation technique	Appraised value; independent market prices	Appraised value; independent market prices
Significant unobservable inputs	Discounts to reflect current market conditions and estimated costs to sell	Discounts to reflect current market conditions and estimated costs to sell
General range of significant input values, minimum	0.00%	0.00%
General range of significant input values, maximum	10.00%	10.00%
Foreclosed Real Estate - Non-Covered [Member]
Other real estate - non-covered	$ 8,978	$ 9,771
Valuation technique	Appraised value; independent market prices	Appraised value; independent market prices
Significant unobservable inputs	Discounts to reflect current market conditions, abbreviated holding period and estimated costs to sell	Discounts to reflect current market conditions, abbreviated holding period and estimated costs to sell
General range of significant input values, minimum	0.00%	0.00%
General range of significant input values, maximum	40.00%	40.00%

The maximum general range of significant unobservable input values.

No definition available.

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- Definition

The minimum general range of significant unobservable input values.

+ References

No definition available.

+ Details

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- Definition

Fair value of impaired loans covered by loss sharing arrangements.

+ References

No definition available.

+ Details

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- Definition

Fair value of impaired loans not covered by loss sharing arrangements.

+ References

No definition available.

+ Details

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- Definition

fair value of other real estate covered by loss sharing agreements.

+ References

No definition available.

+ Details

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- Definition

Fair value of other real estate not covered by loss sharing agreements.

+ References

No definition available.

+ Details

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- Definition

Description of significant assumptions used by management to measure fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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