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Allowance Allocations (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 [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | $ 61,566 |  |  |  | $ 55,825 | $ 61,566 | $ 55,825 | $ 55,100 |
Charge-offs |  |  |  |  |  |  |  |  | (6,209) | (3,472) | (4,918) |
Recoveries |  |  |  |  |  |  |  |  | 2,336 | 3,138 | 4,143 |
Provision (benefit) | $ 1,300 | $ 0 | $ 1,050 | 600 | $ 4,000 | $ 950 | $ 600 | 525 | 2,950 | 6,075 | 1,500 |
Ending balance | 60,643 |  |  |  | 61,566 |  |  |  | 60,643 | 61,566 | 55,825 |
Ending balance: individually evaluated for impairment | 1,342 |  |  |  | 5,214 |  |  |  | 1,342 | 5,214 | 1,930 |
Ending balance: collectively evaluated for impairment | 59,301 |  |  |  | 56,352 |  |  |  | 59,301 | 56,352 | 53,895 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 6,269,729 |  |  |  | 5,903,916 |  |  |  | 6,269,729 | 5,903,916 | 5,475,716 |
Individually evaluated for impairment | 72,801 |  |  |  | 77,297 |  |  |  | 72,801 | 77,297 | 51,410 |
Financing Receivable, Net | 4,539,256 |  |  |  | 4,355,968 |  |  |  | 4,539,256 | 4,355,968 |  |
Loans Receivable, Gross, Commercial and Industrial | 888,528 |  |  |  | 902,053 |  |  |  | 888,528 | 902,053 |  |
Loans Receivable, Gross, Commercial, Mortgage | 3,116,561 |  |  |  | 3,010,798 |  |  |  | 3,116,561 | 3,010,798 |  |
Total loans | 6,355,553 |  |  |  | 5,999,605 |  |  |  | 6,355,553 | 5,999,605 | 5,547,721 | [1]
Loans and Leases Receivable, Gross, Consumer, Other | 9,880 |  |  |  | 11,064 |  |  |  | 9,880 | 11,064 |  |
Loans Receivable, Gross, Commercial, Construction | 401,797 |  |  |  | 320,391 |  |  |  | 401,797 | 320,391 |  |
Small Business | 132,370 |  |  |  | 122,726 |  |  |  | 132,370 | 122,726 |  |
Loans and Leases Receivable, Gross, Consumer, Mortgage | 754,329 |  |  |  | 644,426 |  |  |  | 754,329 | 644,426 |  |
Commercial and Industrial [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 16,921 |  |  |  | 13,802 | 16,921 | 13,802 | 15,573 |
Charge-offs |  |  |  |  |  |  |  |  | (3,891) | (593) | (2,010) |
Recoveries |  |  |  |  |  |  |  |  | 615 | 859 | 1,593 |
Provision (benefit) |  |  |  |  |  |  |  |  | (389) | 2,853 | (1,354) |
Ending balance | 13,256 |  |  |  | 16,921 |  |  |  | 13,256 | 16,921 | 13,802 |
Ending balance: individually evaluated for impairment | 10 |  |  |  | 3,661 |  |  |  | 10 | 3,661 | 183 |
Ending balance: collectively evaluated for impairment | 13,246 |  |  |  | 13,260 |  |  |  | 13,246 | 13,260 | 13,619 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 853,885 |  |  |  | 862,875 |  |  |  | 853,885 | 862,875 | 838,129 |
Individually evaluated for impairment | 34,643 |  |  |  | 39,178 |  |  |  | 34,643 | 39,178 | 5,147 |
Financing Receivable, Net | 888,528 |  |  |  | 902,053 |  |  |  | 888,528 | 902,053 |  |
Total loans | 888,528 |  |  |  | 902,053 |  |  |  | 888,528 | 902,053 | 843,276 |
Commercial Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 30,369 |  |  |  | 27,327 | 30,369 | 27,327 | 25,873 |
Charge-offs |  |  |  |  |  |  |  |  | (39) | (414) | (330) |
Recoveries |  |  |  |  |  |  |  |  | 385 | 564 | 1,073 |
Provision (benefit) |  |  |  |  |  |  |  |  | 738 | 2,892 | 711 |
Ending balance | 31,453 |  |  |  | 30,369 |  |  |  | 31,453 | 30,369 | 27,327 |
Ending balance: individually evaluated for impairment | 42 |  |  |  | 196 |  |  |  | 42 | 196 | 204 |
Ending balance: collectively evaluated for impairment | 31,411 |  |  |  | 30,173 |  |  |  | 31,411 | 30,173 | 27,123 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 3,093,945 |  |  |  | 2,983,642 |  |  |  | 3,093,945 | 2,983,642 | 2,619,294 |
Individually evaluated for impairment | 16,638 |  |  |  | 16,813 |  |  |  | 16,638 | 16,813 | 22,986 |
Financing Receivable, Net | 3,116,561 |  |  |  | 3,010,798 |  |  |  | 3,116,561 | 3,010,798 |  |
Total loans | 3,116,561 |  |  |  | 3,010,798 |  |  |  | 3,116,561 | 3,010,798 | 2,653,434 |
Construction Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 4,522 |  |  |  | 5,366 | 4,522 | 5,366 | 3,945 |
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0 |
Recoveries |  |  |  |  |  |  |  |  | 0 | 0 |  |
Provision (benefit) |  |  |  |  |  |  |  |  | 1,176 | (844) | 1,421 |
Ending balance | 5,698 |  |  |  | 4,522 |  |  |  | 5,698 | 4,522 | 5,366 |
Ending balance: individually evaluated for impairment | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Ending balance: collectively evaluated for impairment | 5,698 |  |  |  | 4,522 |  |  |  | 5,698 | 4,522 | 5,366 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 401,797 |  |  |  | 320,391 |  |  |  | 401,797 | 320,391 | 373,064 |
Individually evaluated for impairment | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 304 |
Financing Receivable, Net | 401,797 |  |  |  | 320,391 |  |  |  | 401,797 | 320,391 |  |
Total loans | 401,797 |  |  |  | 320,391 |  |  |  | 401,797 | 320,391 | 373,368 |
Small Business [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 1,502 |  |  |  | 1,264 | 1,502 | 1,264 | 1,171 |
Charge-offs |  |  |  |  |  |  |  |  | (302) | (228) | (267) |
Recoveries |  |  |  |  |  |  |  |  | 114 | 195 | 264 |
Provision (benefit) |  |  |  |  |  |  |  |  | 263 | 271 | 96 |
Ending balance | 1,577 |  |  |  | 1,502 |  |  |  | 1,577 | 1,502 | 1,264 |
Ending balance: individually evaluated for impairment | 1 |  |  |  | 8 |  |  |  | 1 | 8 | 4 |
Ending balance: collectively evaluated for impairment | 1,576 |  |  |  | 1,494 |  |  |  | 1,576 | 1,494 | 1,260 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 131,667 |  |  |  | 121,855 |  |  |  | 131,667 | 121,855 | 95,225 |
Individually evaluated for impairment | 703 |  |  |  | 871 |  |  |  | 703 | 871 | 1,021 |
Financing Receivable, Net | 132,370 |  |  |  | 122,726 |  |  |  | 132,370 | 122,726 |  |
Total loans | 132,370 |  |  |  | 122,726 |  |  |  | 132,370 | 122,726 | 96,246 |
Residential Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 2,621 |  |  |  | 2,590 | 2,621 | 2,590 | 2,834 |
Charge-offs |  |  |  |  |  |  |  |  | (207) | (28) | (285) |
Recoveries |  |  |  |  |  |  |  |  | 31 | 299 | 133 |
Provision (benefit) |  |  |  |  |  |  |  |  | 377 | (240) | (92) |
Ending balance | 2,822 |  |  |  | 2,621 |  |  |  | 2,822 | 2,621 | 2,590 |
Ending balance: individually evaluated for impairment | 1,007 |  |  |  | 1,086 |  |  |  | 1,007 | 1,086 | 1,278 |
Ending balance: collectively evaluated for impairment | 1,815 |  |  |  | 1,535 |  |  |  | 1,815 | 1,535 | 1,312 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 733,809 |  |  |  | 622,392 |  |  |  | 733,809 | 622,392 | 614,014 |
Individually evaluated for impairment | 13,684 |  |  |  | 14,175 |  |  |  | 13,684 | 14,175 | 15,405 |
Total loans | 754,329 |  |  |  | 644,426 |  |  |  | 754,329 | 644,426 | 638,606 |
Home Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | 5,238 |  |  |  | 4,889 | 5,238 | 4,889 | 4,956 |
Charge-offs |  |  |  |  |  |  |  |  | (276) | (602) | (710) |
Recoveries |  |  |  |  |  |  |  |  | 198 | 141 | 356 |
Provision (benefit) |  |  |  |  |  |  |  |  | 230 | 810 | 287 |
Ending balance | 5,390 |  |  |  | 5,238 |  |  |  | 5,390 | 5,238 | 4,889 |
Ending balance: individually evaluated for impairment | 265 |  |  |  | 242 |  |  |  | 265 | 242 | 238 |
Ending balance: collectively evaluated for impairment | 5,125 |  |  |  | 4,996 |  |  |  | 5,125 | 4,996 | 4,651 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 1,045,053 |  |  |  | 982,095 |  |  |  | 1,045,053 | 982,095 | 921,563 |
Individually evaluated for impairment | 6,826 |  |  |  | 5,863 |  |  |  | 6,826 | 5,863 | 5,989 |
Total loans | 1,052,088 |  |  |  | 988,147 |  |  |  | 1,052,088 | 988,147 | 927,803 |
Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance |  |  |  | $ 393 |  |  |  | $ 587 | 393 | 587 | 748 |
Charge-offs |  |  |  |  |  |  |  |  | (1,494) | (1,607) | (1,316) |
Recoveries |  |  |  |  |  |  |  |  | 993 | 1,080 | 724 |
Provision (benefit) |  |  |  |  |  |  |  |  | 555 | 333 | 431 |
Ending balance | 447 |  |  |  | 393 |  |  |  | 447 | 393 | 587 |
Ending balance: individually evaluated for impairment | 17 |  |  |  | 21 |  |  |  | 17 | 21 | 23 |
Ending balance: collectively evaluated for impairment | 430 |  |  |  | 372 |  |  |  | 430 | 372 | 564 |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Collectively Evaluated for Impairment | 9,573 |  |  |  | 10,666 |  |  |  | 9,573 | 10,666 | 14,427 |
Individually evaluated for impairment | 307 |  |  |  | 397 |  |  |  | 307 | 397 | 558 |
Total loans | 9,880 |  |  |  | 11,064 |  |  |  | 9,880 | 11,064 | 14,988 |
Receivables Acquired with Deteriorated Credit Quality [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 13,023 |  |  |  | 18,392 |  |  |  | 13,023 | 18,392 | 20,595 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Commercial and Industrial [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Commercial Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 5,978 |  |  |  | 10,343 |  |  |  | 5,978 | 10,343 | 11,154 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Construction Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Small Business [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Residential Real Estate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 6,836 |  |  |  | 7,859 |  |  |  | 6,836 | 7,859 | 9,187 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Home Equity [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | 209 |  |  |  | 189 |  |  |  | 209 | 189 | 251 |
Receivables Acquired with Deteriorated Credit Quality [Member] | Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financing receivables ending balance: |  |  |  |  |  |  |  |  |  |  |  |
Financing Receivable, Net | $ 0 |  |  |  | $ 1 |  |  |  | $ 0 | $ 1 | $ 3 |
[1] | The amount of net deferred costs on originated loans included in the ending balance was $6.1 million, $5.1 million, and $4.3 million at December 31, 2017, 2016, and 2015, respectively. Net unamortized discounts on acquired loans not deemed to be PCI included in the ending balance was $9.4 million, $8.6 million, and $6.6 million at December 31, 2017, 2016, and 2015, respectively.

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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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