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Loans Receivable, Net (Details 2) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | $ 55,215 | $ 62,759
Loans with a specific valuation allowance, Unpaid principal balance | 62,209 | 70,261
Loans with a specific valuation allowance, Average balance | 58,987 | 76,656
Loans without a specific valuation allowance, Recorded balance | 138,641 | 138,976
Loans without a specific valuation allowance, Unpaid principal balance | 159,062 | 149,412
Loans without a specific valuation allowance, Average balance | 138,807 | 162,505
Recorded balance | 193,856 | 201,735
Unpaid principal balance | 221,271 | 219,673
Specific valuation allowance | 11,601 | 15,534
Average balance | 197,794 | 239,161
Residential Real Estate [Member] |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | 6,754 | 7,334
Loans with a specific valuation allowance, Unpaid principal balance | 6,868 | 7,459
Loans with a specific valuation allowance, Average balance | 7,044 | 12,797
Loans without a specific valuation allowance, Recorded balance | 18,190 | 18,528
Loans without a specific valuation allowance, Unpaid principal balance | 19,275 | 19,613
Loans without a specific valuation allowance, Average balance | 18,359 | 16,034
Recorded balance | 24,944 | 25,862
Unpaid principal balance | 26,143 | 27,072
Specific valuation allowance | 1,144 | 1,680
Average balance | 25,403 | 28,831
Commercial Real Estate [Member] |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | 23,965 | 29,595
Loans with a specific valuation allowance, Unpaid principal balance | 30,710 | 36,887
Loans with a specific valuation allowance, Average balance | 26,780 | 36,164
Loans without a specific valuation allowance, Recorded balance | 97,391 | 95,687
Loans without a specific valuation allowance, Unpaid principal balance | 113,126 | 102,798
Loans without a specific valuation allowance, Average balance | 96,539 | 111,554
Recorded balance | 121,356 | 125,282
Unpaid principal balance | 143,836 | 139,685
Specific valuation allowance | 5,598 | 7,716
Average balance | 123,319 | 147,718
Other Commercial [Member] |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | 20,521 | 21,205
Loans with a specific valuation allowance, Unpaid principal balance | 20,593 | 21,278
Loans with a specific valuation allowance, Average balance | 20,863 | 22,665
Loans without a specific valuation allowance, Recorded balance | 12,119 | 12,388
Loans without a specific valuation allowance, Unpaid principal balance | 14,415 | 14,318
Loans without a specific valuation allowance, Average balance | 12,253 | 19,733
Recorded balance | 32,640 | 33,593
Unpaid principal balance | 35,008 | 35,596
Specific valuation allowance | 3,302 | 3,859
Average balance | 33,116 | 42,398
Home Equity [Member] |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | 602 | 1,354
Loans with a specific valuation allowance, Unpaid principal balance | 615 | 1,362
Loans with a specific valuation allowance, Average balance | 978 | 1,390
Loans without a specific valuation allowance, Recorded balance | 8,817 | 9,720
Loans without a specific valuation allowance, Unpaid principal balance | 10,082 | 9,965
Loans without a specific valuation allowance, Average balance | 9,268 | 11,993
Recorded balance | 9,419 | 11,074
Unpaid principal balance | 10,697 | 11,327
Specific valuation allowance | 270 | 870
Average balance | 10,246 | 13,383
Other Consumer [Member] |  |
Summary of the impaired loans by portfolio class of loans |  |
Loans with a specific valuation allowance, Recorded balance | 3,373 | 3,271
Loans with a specific valuation allowance, Unpaid principal balance | 3,423 | 3,275
Loans with a specific valuation allowance, Average balance | 3,322 | 3,640
Loans without a specific valuation allowance, Recorded balance | 2,124 | 2,653
Loans without a specific valuation allowance, Unpaid principal balance | 2,164 | 2,718
Loans without a specific valuation allowance, Average balance | 2,388 | 3,191
Recorded balance | 5,497 | 5,924
Unpaid principal balance | 5,587 | 5,993
Specific valuation allowance | 1,287 | 1,409
Average balance | $ 5,710 | $ 6,831

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