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Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | $ 62,614 | $ 62,614 | $ 62,759
Loans with a specific valuation allowance, Unpaid principal balance | 64,969 | 64,969 | 70,261
Loans with a specific valuation allowance, Specific valuation allowance | 12,728 | 12,728 | 15,534
Loans with a specific valuation allowance, Average balance | 59,817 | 59,402 | 76,656
Loans without a specific valuation allowance, Recorded balance | 144,304 | 144,304 | 138,976
Loans without a specific valuation allowance, Unpaid principal balance | 174,258 | 174,258 | 149,412
Loans without a specific valuation allowance, Average balance | 139,928 | 139,368 | 162,505
Recorded balance | 206,918 | 206,918 | 201,735
Unpaid principal balance | 239,227 | 239,227 | 219,673
Specific valuation allowance | 12,728 | 12,728 | 15,534
Average balance | 199,745 | 198,770 | 239,161
Residential Real Estate |  |  |
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | 7,887 | 7,887 | 7,334
Loans with a specific valuation allowance, Unpaid principal balance | 8,032 | 8,032 | 7,459
Loans with a specific valuation allowance, Specific valuation allowance | 1,088 | 1,088 | 1,680
Loans with a specific valuation allowance, Average balance | 7,431 | 7,237 | 12,797
Loans without a specific valuation allowance, Recorded balance | 19,217 | 19,217 | 18,528
Loans without a specific valuation allowance, Unpaid principal balance | 20,681 | 20,681 | 19,613
Loans without a specific valuation allowance, Average balance | 18,481 | 18,420 | 16,034
Recorded balance | 27,104 | 27,104 | 25,862
Unpaid principal balance | 28,713 | 28,713 | 27,072
Specific valuation allowance | 1,088 | 1,088 | 1,680
Average balance | 25,912 | 25,657 | 28,831
Commercial Real Estate |  |  |
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | 28,194 | 28,194 | 29,595
Loans with a specific valuation allowance, Unpaid principal balance | 29,463 | 29,463 | 36,887
Loans with a specific valuation allowance, Specific valuation allowance | 6,662 | 6,662 | 7,716
Loans with a specific valuation allowance, Average balance | 26,525 | 26,653 | 36,164
Loans without a specific valuation allowance, Recorded balance | 97,372 | 97,372 | 95,687
Loans without a specific valuation allowance, Unpaid principal balance | 120,914 | 120,914 | 102,798
Loans without a specific valuation allowance, Average balance | 95,175 | 95,857 | 111,554
Recorded balance | 125,566 | 125,566 | 125,282
Unpaid principal balance | 150,377 | 150,377 | 139,685
Specific valuation allowance | 6,662 | 6,662 | 7,716
Average balance | 121,700 | 122,510 | 147,718
Other Commercial |  |  |
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | 22,368 | 22,368 | 21,205
Loans with a specific valuation allowance, Unpaid principal balance | 22,986 | 22,986 | 21,278
Loans with a specific valuation allowance, Specific valuation allowance | 3,810 | 3,810 | 3,859
Loans with a specific valuation allowance, Average balance | 21,780 | 21,321 | 22,665
Loans without a specific valuation allowance, Recorded balance | 16,022 | 16,022 | 12,388
Loans without a specific valuation allowance, Unpaid principal balance | 19,233 | 19,233 | 14,318
Loans without a specific valuation allowance, Average balance | 15,768 | 14,011 | 19,733
Recorded balance | 38,390 | 38,390 | 33,593
Unpaid principal balance | 42,219 | 42,219 | 35,596
Specific valuation allowance | 3,810 | 3,810 | 3,859
Average balance | 37,548 | 35,332 | 42,398
Home Equity |  |  |
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | 673 | 673 | 1,354
Loans with a specific valuation allowance, Unpaid principal balance | 717 | 717 | 1,362
Loans with a specific valuation allowance, Specific valuation allowance | 109 | 109 | 870
Loans with a specific valuation allowance, Average balance | 495 | 737 | 1,390
Loans without a specific valuation allowance, Recorded balance | 9,418 | 9,418 | 9,720
Loans without a specific valuation allowance, Unpaid principal balance | 11,026 | 11,026 | 9,965
Loans without a specific valuation allowance, Average balance | 8,766 | 9,017 | 11,993
Recorded balance | 10,091 | 10,091 | 11,074
Unpaid principal balance | 11,743 | 11,743 | 11,327
Specific valuation allowance | 109 | 109 | 870
Average balance | 9,261 | 9,754 | 13,383
Other Consumer |  |  |
Summary of the impaired loans by portfolio class of loans |  |  |
Loans with a specific valuation allowance, Recorded balance | 3,492 | 3,492 | 3,271
Loans with a specific valuation allowance, Unpaid principal balance | 3,771 | 3,771 | 3,275
Loans with a specific valuation allowance, Specific valuation allowance | 1,059 | 1,059 | 1,409
Loans with a specific valuation allowance, Average balance | 3,586 | 3,454 | 3,640
Loans without a specific valuation allowance, Recorded balance | 2,275 | 2,275 | 2,653
Loans without a specific valuation allowance, Unpaid principal balance | 2,404 | 2,404 | 2,718
Loans without a specific valuation allowance, Average balance | 1,738 | 2,063 | 3,191
Recorded balance | 5,767 | 5,767 | 5,924
Unpaid principal balance | 6,175 | 6,175 | 5,993
Specific valuation allowance | 1,059 | 1,059 | 1,409
Average balance | $ 5,324 | $ 5,517 | $ 6,831

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