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Allowance Allocations (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | $ 60,643 |  |  |  | $ 61,566 | $ 60,643 | $ 61,566 | $ 55,825 |
Charge-offs |  |  |  |  |  |  |  |  | (2,597) | (6,209) | (3,472) |
Recoveries |  |  |  |  |  |  |  |  | 1,472 | 2,336 | 3,138 |
Provision (benefit) | $ 1,200 | $ 1,075 | $ 2,000 | 500 | $ 1,300 | $ 0 | $ 1,050 | 600 | 4,775 | 2,950 | 6,075 |
Ending balance | 64,293 |  |  |  | 60,643 |  |  |  | 64,293 | 60,643 | 61,566 |
Ending balance: collectively evaluated for impairment | 63,214 |  |  |  | 59,301 |  |  |  | 63,214 | 59,301 | 56,352 |
Ending balance: individually evaluated for impairment | 1,079 |  |  |  | 1,342 |  |  |  | 1,079 | 1,342 | 5,214 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 6,838,339 |  |  |  | 6,269,729 |  |  |  | 6,838,339 | 6,269,729 | 5,903,916 |
Individually evaluated for impairment | 59,060 |  |  |  | 72,801 |  |  |  | 59,060 | 72,801 | 77,297 |
Financing Receivable, Net | 4,874,718 |  |  |  | 4,539,256 |  |  |  | 4,874,718 | 4,539,256 |  |
Total loans | 6,906,194 |  |  |  | 6,355,553 |  |  |  | 6,906,194 | 6,355,553 | 5,999,605 | [1]
Commercial and Industrial [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 13,256 |  |  |  | 16,921 | 13,256 | 16,921 | 13,802 |
Charge-offs |  |  |  |  |  |  |  |  | (355) | (3,891) | (593) |
Recoveries |  |  |  |  |  |  |  |  | 182 | 615 | 859 |
Provision (benefit) |  |  |  |  |  |  |  |  | 2,677 | (389) | 2,853 |
Ending balance | 15,760 |  |  |  | 13,256 |  |  |  | 15,760 | 13,256 | 16,921 |
Ending balance: collectively evaluated for impairment | 15,753 |  |  |  | 13,246 |  |  |  | 15,753 | 13,246 | 13,260 |
Ending balance: individually evaluated for impairment | 7 |  |  |  | 10 |  |  |  | 7 | 10 | 3,661 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 1,064,800 |  |  |  | 853,885 |  |  |  | 1,064,800 | 853,885 | 862,875 |
Individually evaluated for impairment | 28,829 |  |  |  | 34,643 |  |  |  | 28,829 | 34,643 | 39,178 |
Financing Receivable, Net | 1,093,629 |  |  |  | 888,528 |  |  |  | 1,093,629 | 888,528 |  |
Total loans | 1,093,629 |  |  |  | 888,528 |  |  |  | 1,093,629 | 888,528 | 902,053 |
Commercial Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 31,453 |  |  |  | 30,369 | 31,453 | 30,369 | 27,327 |
Charge-offs |  |  |  |  |  |  |  |  | (82) | (39) | (414) |
Recoveries |  |  |  |  |  |  |  |  | 188 | 385 | 564 |
Provision (benefit) |  |  |  |  |  |  |  |  | 811 | 738 | 2,892 |
Ending balance | 32,370 |  |  |  | 31,453 |  |  |  | 32,370 | 31,453 | 30,369 |
Ending balance: collectively evaluated for impairment | 32,333 |  |  |  | 31,411 |  |  |  | 32,333 | 31,411 | 30,173 |
Ending balance: individually evaluated for impairment | 37 |  |  |  | 42 |  |  |  | 37 | 42 | 196 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 3,235,418 |  |  |  | 3,093,945 |  |  |  | 3,235,418 | 3,093,945 | 2,983,642 |
Individually evaluated for impairment | 10,839 |  |  |  | 16,638 |  |  |  | 10,839 | 16,638 | 16,813 |
Financing Receivable, Net | 3,251,248 |  |  |  | 3,116,561 |  |  |  | 3,251,248 | 3,116,561 |  |
Total loans | 3,251,248 |  |  |  | 3,116,561 |  |  |  | 3,251,248 | 3,116,561 | 3,010,798 |
Construction Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 5,698 |  |  |  | 4,522 | 5,698 | 4,522 | 5,366 |
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0 |
Recoveries |  |  |  |  |  |  |  |  | 0 | 0 | 0 |
Provision (benefit) |  |  |  |  |  |  |  |  | (540) | 1,176 | (844) |
Ending balance | 5,158 |  |  |  | 5,698 |  |  |  | 5,158 | 5,698 | 4,522 |
Ending balance: collectively evaluated for impairment | 5,158 |  |  |  | 5,698 |  |  |  | 5,158 | 5,698 | 4,522 |
Ending balance: individually evaluated for impairment | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 365,165 |  |  |  | 401,797 |  |  |  | 365,165 | 401,797 | 320,391 |
Individually evaluated for impairment | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Financing Receivable, Net | 365,165 |  |  |  | 401,797 |  |  |  | 365,165 | 401,797 |  |
Total loans | 365,165 |  |  |  | 401,797 |  |  |  | 365,165 | 401,797 | 320,391 |
Small Business [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 1,577 |  |  |  | 1,502 | 1,577 | 1,502 | 1,264 |
Charge-offs |  |  |  |  |  |  |  |  | (372) | (302) | (228) |
Recoveries |  |  |  |  |  |  |  |  | 46 | 114 | 195 |
Provision (benefit) |  |  |  |  |  |  |  |  | 505 | 263 | 271 |
Ending balance | 1,756 |  |  |  | 1,577 |  |  |  | 1,756 | 1,577 | 1,502 |
Ending balance: collectively evaluated for impairment | 1,755 |  |  |  | 1,576 |  |  |  | 1,755 | 1,576 | 1,494 |
Ending balance: individually evaluated for impairment | 1 |  |  |  | 1 |  |  |  | 1 | 1 | 8 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 164,135 |  |  |  | 131,667 |  |  |  | 164,135 | 131,667 | 121,855 |
Individually evaluated for impairment | 541 |  |  |  | 703 |  |  |  | 541 | 703 | 871 |
Financing Receivable, Net | 164,676 |  |  |  | 132,370 |  |  |  | 164,676 | 132,370 |  |
Total loans | 164,676 |  |  |  | 132,370 |  |  |  | 164,676 | 132,370 | 122,726 |
Residential Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 2,822 |  |  |  | 2,621 | 2,822 | 2,621 | 2,590 |
Charge-offs |  |  |  |  |  |  |  |  | (148) | (207) | (28) |
Recoveries |  |  |  |  |  |  |  |  | 12 | 31 | 299 |
Provision (benefit) |  |  |  |  |  |  |  |  | 533 | 377 | (240) |
Ending balance | 3,219 |  |  |  | 2,822 |  |  |  | 3,219 | 2,822 | 2,621 |
Ending balance: collectively evaluated for impairment | 2,357 |  |  |  | 1,815 |  |  |  | 2,357 | 1,815 | 1,535 |
Ending balance: individually evaluated for impairment | 862 |  |  |  | 1,007 |  |  |  | 862 | 1,007 | 1,086 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 906,959 |  |  |  | 733,809 |  |  |  | 906,959 | 733,809 | 622,392 |
Individually evaluated for impairment | 12,706 |  |  |  | 13,684 |  |  |  | 12,706 | 13,684 | 14,175 |
Total loans | 923,294 |  |  |  | 754,329 |  |  |  | 923,294 | 754,329 | 644,426 |
Home Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 5,390 |  |  |  | 5,238 | 5,390 | 5,238 | 4,889 |
Charge-offs |  |  |  |  |  |  |  |  | (293) | (276) | (602) |
Recoveries |  |  |  |  |  |  |  |  | 156 | 198 | 141 |
Provision (benefit) |  |  |  |  |  |  |  |  | 355 | 230 | 810 |
Ending balance | 5,608 |  |  |  | 5,390 |  |  |  | 5,608 | 5,390 | 5,238 |
Ending balance: collectively evaluated for impairment | 5,444 |  |  |  | 5,125 |  |  |  | 5,444 | 5,125 | 4,996 |
Ending balance: individually evaluated for impairment | 164 |  |  |  | 265 |  |  |  | 164 | 265 | 242 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 1,085,961 |  |  |  | 1,045,053 |  |  |  | 1,085,961 | 1,045,053 | 982,095 |
Individually evaluated for impairment | 5,948 |  |  |  | 6,826 |  |  |  | 5,948 | 6,826 | 5,863 |
Total loans | 1,092,084 |  |  |  | 1,052,088 |  |  |  | 1,092,084 | 1,052,088 | 988,147 |
Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | $ 447 |  |  |  | $ 393 | 447 | 393 | 587 |
Charge-offs |  |  |  |  |  |  |  |  | (1,347) | (1,494) | (1,607) |
Recoveries |  |  |  |  |  |  |  |  | 888 | 993 | 1,080 |
Provision (benefit) |  |  |  |  |  |  |  |  | 434 | 555 | 333 |
Ending balance | 422 |  |  |  | 447 |  |  |  | 422 | 447 | 393 |
Ending balance: collectively evaluated for impairment | 414 |  |  |  | 430 |  |  |  | 414 | 430 | 372 |
Ending balance: individually evaluated for impairment | 8 |  |  |  | 17 |  |  |  | 8 | 17 | 21 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 15,901 |  |  |  | 9,573 |  |  |  | 15,901 | 9,573 | 10,666 |
Individually evaluated for impairment | 197 |  |  |  | 307 |  |  |  | 197 | 307 | 397 |
Total loans | 16,098 |  |  |  | 9,880 |  |  |  | 16,098 | 9,880 | 11,064 |
Financial Asset Acquired with Credit Deterioration [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 8,795 |  |  |  | 13,023 |  |  |  | 8,795 | 13,023 | 18,392 |
Financial Asset Acquired with Credit Deterioration [Member] | Commercial and Industrial [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Financial Asset Acquired with Credit Deterioration [Member] | Commercial Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 4,991 |  |  |  | 5,978 |  |  |  | 4,991 | 5,978 | 10,343 |
Financial Asset Acquired with Credit Deterioration [Member] | Construction Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Financial Asset Acquired with Credit Deterioration [Member] | Small Business [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Financial Asset Acquired with Credit Deterioration [Member] | Residential Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 3,629 |  |  |  | 6,836 |  |  |  | 3,629 | 6,836 | 7,859 |
Financial Asset Acquired with Credit Deterioration [Member] | Home Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 175 |  |  |  | 209 |  |  |  | 175 | 209 | 189 |
Financial Asset Acquired with Credit Deterioration [Member] | Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | $ 0 |  |  |  | $ 0 |  |  |  | $ 0 | $ 0 | $ 1 |
[1] | The amount of net deferred costs on originated loans included in the ending balance was $7.1 million, $6.1 million and $5.1 million at December 31, 2018, 2017 and 2016, respectively. Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance were $15.2 million, $9.4 million and $8.6 million at December 31, 2018, 2017 and 2016, respectively.

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