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Allowance for Loan Losses, Nonperforming Assets and Impaired Loans, Financing Receivable, Impaired (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Mar. 31, 2012 | Dec. 31, 2012
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | $ 17,258 |  | $ 12,987 |  | $ 18,456 |
(A) Total Recorded Investment | 17,222 | [1] |  |  | 18,422 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 16,226 | [1] |  |  | 16,940 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 996 | [1] |  |  | 1,482 | [2]
Related Allowance | 273 |  | 593 |  | 554 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 17,935 | [1],[3] | 14,555 | [3] | 13,540 | [1],[3]
Interest Income Recognized | 10 |  | 24 |  | 9 |
Real Estate Construction [Member] | Construction, Residential [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 123 |  |  |  | 123 |
(A) Total Recorded Investment | 118 | [1] |  |  | 118 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 118 | [1] |  |  | 118 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 118 | [1] |  |  | 1,171 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Real Estate Construction [Member] | Construction, Other [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 6,369 |  |  |  | 6,520 |
(A) Total Recorded Investment | 6,334 | [1] |  |  | 6,487 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 6,334 | [1] |  |  | 6,487 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 6,486 | [1] |  |  | 4,290 | [1]
Interest Income Recognized | 0 |  |  |  | 1 |
Consumer Real Estate [Member] | Equity Lines [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 0 |  |  |  | 0 |
(A) Total Recorded Investment | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 101 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Consumer Real Estate [Member] | Residential Closed end First Liens [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 315 |  |  |  | 783 |
(A) Total Recorded Investment | 315 | [1] |  |  | 785 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 315 | [1] |  |  | 634 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 151 | [2]
Related Allowance | 0 |  |  |  | 43 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 392 | [1] |  |  | 873 | [1]
Interest Income Recognized | 0 |  |  |  | 2 |
Consumer Real Estate [Member] | Residential Closed end Junior Liens [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 80 |  |  |  | 81 |
(A) Total Recorded Investment | 80 | [1] |  |  | 81 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 80 | [1] |  |  | 81 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 142 | [1] |  |  | 234 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Consumer Real Estate [Member] | Investor-owned residential real estate [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 83 |  |  |  |  |
(A) Total Recorded Investment | 84 | [1] |  |  |  |
Recorded Investment in (A) for Which There is No Related Allowance | 84 | [1] |  |  |  |
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  |  |
Related Allowance | 0 |  |  |  |  |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 84 | [1] |  |  |  |
Interest Income Recognized | 0 |  |  |  |  |
Commercial Real Estate [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 4,421 |  |  |  | 5,284 |
(A) Total Recorded Investment | 4,417 | [1] |  |  | 5,288 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 4,417 | [1] |  |  | 5,288 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 4,540 | [1] |  |  | 1,466 | [1]
Interest Income Recognized | 0 |  |  |  | 5 |
Commercial Real Estate [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 5,506 |  |  |  | 5,045 |
(A) Total Recorded Investment | 5,513 | [1] |  |  | 5,043 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 4,587 | [1] |  |  | 4,293 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 926 | [1] |  |  | 750 | [2]
Related Allowance | 269 |  |  |  | 273 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 5,599 | [1] |  |  | 4,806 | [1]
Interest Income Recognized | 10 |  |  |  | 1 |
Commercial Real Estate [Member] | Commercial Real Estate, Other [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 0 |  |  |  | 0 |
(A) Total Recorded Investment | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 0 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Commercial Non Real Estate [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 318 |  |  |  | 574 |
(A) Total Recorded Investment | 318 | [1] |  |  | 574 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 291 | [1] |  |  | 39 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 27 | [1] |  |  | 535 | [2]
Related Allowance | 1 |  |  |  | 231 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 574 | [1] |  |  | 570 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Public Sector and IDA [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 0 |  |  |  | 0 |
(A) Total Recorded Investment | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 0 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Consumer Non Real Estate [Member] | Credit Cards [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 0 |  |  |  | 0 |
(A) Total Recorded Investment | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 0 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Consumer Non Real Estate [Member] | Automobile [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 43 |  |  |  | 46 |
(A) Total Recorded Investment | 43 | [1] |  |  | 46 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 43 | [1] |  |  | 46 | [2]
Related Allowance | 3 |  |  |  | 7 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 4 | [1]
Interest Income Recognized | 0 |  |  |  | 0 |
Consumer Non Real Estate [Member] | Other Consumer [Member] |  |  |  |  |  |
Investment in impaired loans and related allowance [Abstract] |  |  |  |  |  |
Principal Balance | 0 |  |  |  | 0 |
(A) Total Recorded Investment | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is No Related Allowance | 0 | [1] |  |  | 0 | [2]
Recorded Investment in (A) for Which There is a Related Allowance | 0 | [1] |  |  | 0 | [2]
Related Allowance | 0 |  |  |  | 0 |
Impaired financing receivable average recorded investment and interest income recognized [Abstract] |  |  |  |  |  |
Average Recorded Investment | 0 | [1] |  |  | 25 | [1]
Interest Income Recognized | $ 0 |  |  |  | $ 0 |
[1] | Recorded investment includes the unpaid principal balance and any accrued interest and net deferred fees.
[2] | Recorded investment includes the unpaid principal balance, accrued interest and any accrued interest and deferred fees.
[3] | Recorded investment includes principal, accrued interest and net deferred fees.

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- Definition 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) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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)(2) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 + Details
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