Mortgage Banking Derivatives (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Mortgage banking derivative
Change in fair value	$ 567,000	$ 107,000
Sale of loans to investors	303,600,000
Net gain recognized in earnings	567,000	107,000
Federal National Mortgage Association
Mortgage banking derivative
Sale of loans to investors	189,600,000
Federal National Mortgage Association \| Investor concentration risk
Mortgage banking derivative
Percentage of concentration risk	62.50%
Wells Fargo
Mortgage banking derivative
Sale of loans to investors	58,200,000
Wells Fargo \| Investor concentration risk
Mortgage banking derivative
Percentage of concentration risk	19.20%
Not designated as hedging instruments \| Forward contracts
Mortgage banking derivative
Notional amount	28,000,000	26,000,000
Fair value	1,393,000	889,000
Change in fair value	(85,000)	(214,000)
Not designated as hedging instruments \| Rate lock commitments
Mortgage banking derivative
Notional amount	20,855,000	21,266,000
Fair value	1,488,000	882,000
Change in fair value	$ 652,000	$ 321,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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The cash inflow resulting from the sale of loans classified as held-for-sale, (including proceeds from loans sold through mortgage securitization) net of the gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

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Net Increase or Decrease in the fair value of the derivative or group of derivatives included in earnings.

+ References

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The amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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