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ALLL Activity (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | $ 129,572 |  |  |  | $ 129,697 | $ 129,572 | $ 129,697 | $ 129,753
Provision for loan losses | $ 2,886 | $ 3,327 | $ 3,013 | 1,598 | $ 1,139 | $ 626 | $ 0 | 568 | 10,824 | 2,333 | 2,284
Charge-offs |  |  |  |  |  |  |  |  | (19,331) | (11,496) | (7,002)
Recoveries |  |  |  |  |  |  |  |  | 8,503 | 9,038 | 4,662
Balance at end of period | 129,568 |  |  |  | 129,572 |  |  |  | 129,568 | 129,572 | 129,697
Residential Real Estate | Residential Real Estate |  |  |  |  |  |  |  |  |  |  |
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | 12,436 |  |  |  | 14,427 | 12,436 | 14,427 | 14,680
Provision for loan losses |  |  |  |  |  |  |  |  | (1,521) | (1,734) | 640
Charge-offs |  |  |  |  |  |  |  |  | (199) | (464) | (985)
Recoveries |  |  |  |  |  |  |  |  | 82 | 207 | 92
Balance at end of period | 10,798 |  |  |  | 12,436 |  |  |  | 10,798 | 12,436 | 14,427
Commercial | Commercial Real Estate |  |  |  |  |  |  |  |  |  |  |
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | 65,773 |  |  |  | 67,877 | 65,773 | 67,877 | 67,799
Provision for loan losses |  |  |  |  |  |  |  |  | 7,152 | (2,686) | (696)
Charge-offs |  |  |  |  |  |  |  |  | (6,188) | (3,082) | (1,920)
Recoveries |  |  |  |  |  |  |  |  | 1,778 | 3,664 | 2,694
Balance at end of period | 68,515 |  |  |  | 65,773 |  |  |  | 68,515 | 65,773 | 67,877
Commercial | Other Commercial |  |  |  |  |  |  |  |  |  |  |
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | 37,823 |  |  |  | 32,525 | 37,823 | 32,525 | 30,891
Provision for loan losses |  |  |  |  |  |  |  |  | 2,545 | 5,164 | 3,030
Charge-offs |  |  |  |  |  |  |  |  | (2,856) | (1,778) | (2,322)
Recoveries |  |  |  |  |  |  |  |  | 1,791 | 1,912 | 926
Balance at end of period | 39,303 |  |  |  | 37,823 |  |  |  | 39,303 | 37,823 | 32,525
Consumer and Other | Home Equity |  |  |  |  |  |  |  |  |  |  |
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | 7,572 |  |  |  | 8,998 | 7,572 | 8,998 | 9,963
Provision for loan losses |  |  |  |  |  |  |  |  | (1,103) | (520) | (480)
Charge-offs |  |  |  |  |  |  |  |  | (489) | (1,185) | (809)
Recoveries |  |  |  |  |  |  |  |  | 224 | 279 | 324
Balance at end of period | 6,204 |  |  |  | 7,572 |  |  |  | 6,204 | 7,572 | 8,998
Consumer and Other | Other Consumer |  |  |  |  |  |  |  |  |  |  |
Allowance for loan and lease losses |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of period |  |  |  | $ 5,968 |  |  |  | $ 5,870 | 5,968 | 5,870 | 6,420
Provision for loan losses |  |  |  |  |  |  |  |  | 3,751 | 2,109 | (210)
Charge-offs |  |  |  |  |  |  |  |  | (9,599) | (4,987) | (966)
Recoveries |  |  |  |  |  |  |  |  | 4,628 | 2,976 | 626
Balance at end of period | $ 4,748 |  |  |  | $ 5,968 |  |  |  | $ 4,748 | $ 5,968 | $ 5,870

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