Loans Receivable and Allowance for Loan Losses (Impaired Loans and Related Interest Income by Loan Portfolio Class) (Details) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	$ 6,078,000	$ 6,807,000
Impaired Financing Receivable, with Related Allowance, Recorded Investment	8,031,000	6,823,000
Impaired Financing Receivable, Recorded Investment	14,109,000	13,630,000
Unpaid Principal Balance, With no related allowance recorded	6,202,000	6,978,000
Unpaid Principal Balance, With an allowance recorded	8,031,000	6,823,000
Unpaid Principal Balance, Total	14,233,000	13,801,000
Average Recorded Investment, With no related allowance recorded	6,576,000	6,113,000
Average Recorded Investment, With an allowance recorded	7,379,000	9,670,000
Average Recorded Investment, Total	13,955,000	15,783,000
Interest Income Recognized, With no related allowance recorded	42,000	357,000
Interest Income Recognized, With an allowance recorded	106,000	204,000
Interest Income Recognized, Total	148,000	561,000
Financing Receivable, Modifications, Recorded Investment	7,100,000	7,200,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	991,000,000	1,200,000
Financing Receivable, Modifications, Subsequent Default, Recorded Investment		0
New Loans Identified as Troubled Debt Restructurings		0
Residential Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	273,000	343,000
Impaired Financing Receivable, Recorded Investment	273,000	343,000
Unpaid Principal Balance, With no related allowance recorded	297,000	385,000
Unpaid Principal Balance, Total	297,000	385,000
Average Recorded Investment, With no related allowance recorded	289,000	245,000
Average Recorded Investment, Total	289,000	245,000
Interest Income Recognized, With no related allowance recorded	2,000	7,000
Interest Income Recognized, Total	2,000	7,000
Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	5,420,000	5,866,000
Impaired Financing Receivable, with Related Allowance, Recorded Investment	8,031,000	6,823,000
Impaired Financing Receivable, Recorded Investment	13,451,000	12,689,000
Unpaid Principal Balance, With no related allowance recorded	5,520,000	5,995,000
Unpaid Principal Balance, With an allowance recorded	8,031,000	6,823,000
Unpaid Principal Balance, Total	13,551,000	12,818,000
Associated Allowance	1,120,000	1,231,000
Average Recorded Investment, With no related allowance recorded	5,902,000	5,372,000
Average Recorded Investment, With an allowance recorded	7,379,000	9,670,000
Average Recorded Investment, Total	13,281,000	15,042,000
Interest Income Recognized, With no related allowance recorded	40,000	340,000
Interest Income Recognized, With an allowance recorded	106,000	204,000
Interest Income Recognized, Total	146,000	544,000
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	385,000	598,000
Impaired Financing Receivable, Recorded Investment	385,000	598,000
Unpaid Principal Balance, With no related allowance recorded	385,000	598,000
Unpaid Principal Balance, Total	385,000	598,000
Average Recorded Investment, With no related allowance recorded	385,000	496,000
Average Recorded Investment, Total	385,000	496,000
Interest Income Recognized, With no related allowance recorded		10,000
Interest Income Recognized, Total		$ 10,000

Loans Identified as Troubled Debt Restructurings

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953682-111524

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

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Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

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Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

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Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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