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Allowance for Loan Losses (Tables) | 3 Months Ended
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Mar. 31, 2016
Receivables [Abstract] |
Age Analysis of Past Due Loans Segregated by Class of Loans | The following tables present the age analysis of past due loans segregated by class of loans as of the dates presented:
| March 31, 2016
(dollars in thousands) | Current | 30-59 Days Past Due | 60-89 Days Past Due | Nonaccrual | Total Past Due | Total Loans
Commercial real estate | $ | 2,238,144 |  | $ | 6,669 |  | $ | 174 |  | $ | 15,244 |  | $ | 22,087 |  | $ | 2,260,231 |
Commercial and industrial | 1,306,834 |  | 12,509 |  | 567 |  | 14,209 |  | 27,285 |  | 1,334,119 |
Commercial construction | 364,675 |  | 1,086 |  | 3,539 |  | 9,993 |  | 14,618 |  | 379,293 |
Residential mortgage | 636,328 |  | 1,749 |  | 3,455 |  | 9,012 |  | 14,216 |  | 650,544 |
Home equity | 460,203 |  | 3,754 |  | 447 |  | 3,267 |  | 7,468 |  | 467,671 |
Installment and other consumer | 75,741 |  | 297 |  | 42 |  | 109 |  | 448 |  | 76,189 |
Consumer construction | 8,701 |  | — |  | — |  | — |  | — |  | 8,701 |
Loans held for sale | 11,739 |  | — |  | — |  | — |  | — |  | 11,739 |
Totals | $ | 5,102,365 |  | $ | 26,064 |  | $ | 8,224 |  | $ | 51,834 |  | $ | 86,122 |  | $ | 5,188,487 |
| December 31, 2015
(dollars in thousands) | Current | 30-59 Days Past Due | 60-89 Days Past Due | Nonaccrual | Total Past Due | Total Loans
Commercial real estate | $ | 2,145,655 |  | $ | 11,602 |  | $ | 627 |  | $ | 8,719 |  | $ | 20,948 |  | $ | 2,166,603 |
Commercial and industrial | 1,244,802 |  | 2,453 |  | 296 |  | 9,279 |  | 12,028 |  | 1,256,830 |
Commercial construction | 401,084 |  | 3,517 |  | 90 |  | 8,753 |  | 12,360 |  | 413,444 |
Residential mortgage | 631,085 |  | 1,728 |  | 930 |  | 5,629 |  | 8,287 |  | 639,372 |
Home equity | 465,055 |  | 2,365 |  | 523 |  | 2,902 |  | 5,790 |  | 470,845 |
Installment and other consumer | 73,486 |  | 242 |  | 111 |  | 100 |  | 453 |  | 73,939 |
Consumer construction | 6,579 |  | — |  | — |  | — |  | — |  | 6,579 |
Loans held for sale | 35,179 |  | 94 |  | 48 |  | — |  | 142 |  | 35,321 |
Totals | $ | 5,002,925 |  | $ | 22,001 |  | $ | 2,625 |  | $ | 35,382 |  | $ | 60,008 |  | $ | 5,062,933 |
Recorded Investment in Commercial Loan Classes by Internally Assigned Risk Ratings | The following tables present the recorded investment in commercial loan classes by internally assigned risk ratings as of the dates presented:
| March 31, 2016
(dollars in thousands) | Commercial Real Estate | % of Total |  | Commercial and Industrial | % of Total |  | Commercial Construction | % of Total |  | Total | % of Total
Pass | $ | 2,179,599 |  | 96.4 | % |  | $ | 1,253,947 |  | 94.0 | % |  | $ | 340,469 |  | 89.8 | % |  | $ | 3,774,015 |  | 95.0 | %
Special mention | 26,788 |  | 1.2 | % |  | 28,517 |  | 2.1 | % |  | 20,362 |  | 5.4 | % |  | 75,667 |  | 1.9 | %
Substandard | 53,844 |  | 2.4 | % |  | 51,655 |  | 3.9 | % |  | 18,462 |  | 4.8 | % |  | 123,961 |  | 3.1 | %
Total | $ | 2,260,231 |  | 100 | % |  | $ | 1,334,119 |  | 100.0 | % |  | $ | 379,293 |  | 100.0 | % |  | $ | 3,973,643 |  | 100.0 | %
| December 31, 2015
(dollars in thousands) | Commercial Real Estate | % of Total |  | Commercial and Industrial | % of Total |  | Commercial Construction | % of Total |  | Total | % of Total
Pass | $ | 2,094,851 |  | 96.7 | % |  | $ | 1,182,685 |  | 94.1 | % |  | $ | 375,808 |  | 90.9 | % |  | $ | 3,653,344 |  | 95.2 | %
Special mention | 19,938 |  | 0.9 | % |  | 43,896 |  | 3.5 | % |  | 19,846 |  | 4.8 | % |  | 83,680 |  | 2.2 | %
Substandard | 51,814 |  | 2.4 | % |  | 30,249 |  | 2.4 | % |  | 17,790 |  | 4.3 | % |  | 99,853 |  | 2.6 | %
Total | $ | 2,166,603 |  | 100.0 | % |  | $ | 1,256,830 |  | 100.0 | % |  | $ | 413,444 |  | 100.0 | % |  | $ | 3,836,877 |  | 100.0 | %
Recorded Investment in Consumer Loan Classes by Performing and Nonperforming Status | The following tables present the recorded investment in consumer loan classes by performing and nonperforming status as of the dates presented:
| March 31, 2016
(dollars in thousands) | Residential Mortgage | % of Total | Home Equity | % of Total | Installment and other consumer | % of Total | Consumer Construction | % of Total | Total | % of Total
Performing | $ | 641,532 |  | 98.6 | % | $ | 464,404 |  | 99.3 | % | $ | 76,080 |  | 99.9 | % | $ | 8,701 |  | 100.0 | % | $ | 1,190,717 |  | 99.0 | %
Nonperforming | 9,012 |  | 1.4 | % | 3,267 |  | 0.7 | % | 109 |  | 0.1 | % | — |  | — | % | 12,388 |  | 1.0 | %
Total | $ | 650,544 |  | 100.0 | % | $ | 467,671 |  | 100.0 | % | $ | 76,189 |  | 100.0 | % | $ | 8,701 |  | 100.0 | % | $ | 1,203,105 |  | 100.0 | %
| December 31, 2015
(dollars in thousands) | Residential Mortgage | % of Total | Home Equity | % of Total | Installment and other consumer | % of Total | Consumer Construction | % of Total | Total | % of Total
Performing | $ | 633,743 |  | 99.1 | % | $ | 467,943 |  | 99.4 | % | $ | 73,839 |  | 99.8 | % | $ | 6,579 |  | 100.0 | % | $ | 1,182,104 |  | 99.3 | %
Nonperforming | 5,629 |  | 0.9 | % | 2,902 |  | 0.6 | % | 100 |  | 0.2 | % | — |  | — | % | 8,631 |  | 0.7 | %
Total | $ | 639,372 |  | 100.0 | % | $ | 470,845 |  | 100.0 | % | $ | 73,939 |  | 100.0 | % | $ | 6,579 |  | 100.0 | % | $ | 1,190,735 |  | 100.0 | %
Investments in Loans Considered to be Impaired and Related Information on Impaired Loans | The following tables summarize investments in loans considered to be impaired and related information on those impaired loans for the periods presented:
| Three Months Ended
| March 31, 2016 | March 31, 2015
(dollars in thousands) | Average Recorded Investment | Interest Income Recognized | Average Recorded Investment | Interest Income Recognized
Without a related allowance recorded: |  |  |  |
Commercial real estate | $ | 18,605 |  | $ | 199 |  | $ | 22,627 |  | $ | 164 |
Commercial and industrial | 15,513 |  | 149 |  | 10,847 |  | 62 |
Commercial construction | 10,782 |  | 64 |  | 7,704 |  | 53 |
Consumer real estate | 11,102 |  | 135 |  | 7,073 |  | 96 |
Other consumer | 26 |  | — |  | 34 |  | — |
Total without a Related Allowance Recorded | 56,028 |  | 547 |  | 48,285 |  | 375 |
With a related allowance recorded: |  |  |  |
Commercial real estate | — |  | — |  | 823 |  | 8 |
Commercial and industrial | 5,382 |  | 32 |  | — |  | — |
Commercial construction | 1,117 |  | 6 |  | — |  | — |
Consumer real estate | 115 |  | 2 |  | 42 |  | 1 |
Other consumer | 2 |  | — |  | 19 |  | — |
Total with a Related Allowance Recorded | 6,616 |  | 40 |  | 884 |  | 9 |
Total: |  |  |  |
Commercial real estate | 18,605 |  | 199 |  | 23,450 |  | 172 |
Commercial and industrial | 20,895 |  | 181 |  | 10,847 |  | 62 |
Commercial construction | 11,899 |  | 70 |  | 7,704 |  | 53 |
Consumer real estate | 11,217 |  | 137 |  | 7,115 |  | 97 |
Other consumer | 28 |  | — |  | 53 |  | — |
Total | $ | 62,644 |  | $ | 587 |  | $ | 49,169 |  | $ | 384 |
The following tables summarize investments in loans considered to be impaired and related information on those impaired loans as of the dates presented:
| March 31, 2016 |  | December 31, 2015
(dollars in thousands) | Recorded Investment | Unpaid Principal Balance | Related Allowance |  | Recorded Investment | Unpaid Principal Balance | Related Allowance
Without a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | $ | 18,505 |  | $ | 26,493 |  | $ | — |  |  | $ | 12,661 |  | $ | 13,157 |  | $ | — |
Commercial and industrial | 13,778 |  | 14,750 |  | — |  |  | 14,417 |  | 15,220 |  | — |
Commercial construction | 10,772 |  | 13,974 |  | — |  |  | 10,998 |  | 14,200 |  | — |
Consumer real estate | 11,038 |  | 11,703 |  | — |  |  | 6,845 |  | 7,521 |  | — |
Other consumer | 27 |  | 29 |  | — |  |  | 111 |  | 188 |  | — |
Total without a Related Allowance Recorded | 54,120 |  | 66,949 |  | — |  |  | 45,032 |  | 50,286 |  | — |
With a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | — |  | — |  | — |  |  | — |  | — |  | — |
Commercial and industrial | 4,850 |  | 5,356 |  | 2,027 |  |  | — |  | — |  | — |
Commercial construction | 1,116 |  | 1,966 |  | 154 |  |  | 500 |  | 1,350 |  | 3 |
Consumer real estate | 114 |  | 114 |  | 30 |  |  | 116 |  | 116 |  | 32 |
Other consumer | 2 |  | 2 |  | 2 |  |  | 2 |  | 2 |  | 2 |
Total with a Related Allowance Recorded | 6,082 |  | 7,438 |  | 2,213 |  |  | 618 |  | 1,468 |  | 37 |
Total: |  |  |  |  |  |  |
Commercial real estate | 18,505 |  | 26,493 |  | — |  |  | 12,661 |  | 13,157 |  | — |
Commercial and industrial | 18,628 |  | 20,106 |  | 2,027 |  |  | 14,417 |  | 15,220 |  | — |
Commercial construction | 11,888 |  | 15,940 |  | 154 |  |  | 11,498 |  | 15,550 |  | 3 |
Consumer real estate | 11,152 |  | 11,817 |  | 30 |  |  | 6,961 |  | 7,637 |  | 32 |
Other consumer | 29 |  | 31 |  | 2 |  |  | 113 |  | 190 |  | 2 |
Total | $ | 60,202 |  | $ | 74,387 |  | $ | 2,213 |  |  | $ | 45,650 |  | $ | 51,754 |  | $ | 37 |
Summary of Allowance for Loan Losses | The following tables detail activity in the ALL for the periods presented:
| Three Months Ended March 31, 2016
(dollars in thousands) | Commercial Real Estate |  |  | Commercial and Industrial |  |  | Commercial Construction |  |  | Consumer Real Estate |  |  | Other Consumer |  |  | Total Loans |
Balance at beginning of period | $ | 15,043 |  |  | $ | 10,853 |  |  | $ | 12,625 |  |  | $ | 8,400 |  |  | $ | 1,226 |  |  | $ | 48,147 |
Charge-offs | (54 | ) |  | (2,694 | ) |  | — |  |  | (232 | ) |  | (648 | ) |  | (3,628 | )
Recoveries | 361 |  |  | 203 |  |  | 2 |  |  | 164 |  |  | 84 |  |  | 814 |
Net (Charge-offs)/ Recoveries | 307 |  |  | (2,491 | ) |  | 2 |  |  | (68 | ) |  | (564 | ) |  | (2,814 | )
Provision for loan losses | (84 | ) |  | 6,378 |  |  | (1,802 | ) |  | (71 | ) |  | 593 |  |  | 5,014 |
Balance at End of Period | $ | 15,266 |  |  | $ | 14,740 |  |  | $ | 10,825 |  |  | $ | 8,261 |  |  | $ | 1,255 |  |  | $ | 50,347 |
| Three Months Ended March 31, 2015
(dollars in thousands) | Commercial Real Estate |  |  | Commercial and Industrial |  |  | Commercial Construction |  |  | Consumer Real Estate |  |  | Other Consumer |  |  | Total Loans |
Balance at beginning of period | $ | 20,164 |  |  | $ | 13,668 |  |  | $ | 6,093 |  |  | $ | 6,333 |  |  | $ | 1,653 |  |  | $ | 47,911 |
Charge-offs | (66 | ) |  | (707 | ) |  | — |  |  | (375 | ) |  | (303 | ) |  | (1,451 | )
Recoveries | 103 |  |  | 114 |  |  | 1 |  |  | 136 |  |  | 85 |  |  | 439 |
Net (Charge-offs)/ Recoveries | 37 |  |  | (593 | ) |  | 1 |  |  | (239 | ) |  | (218 | ) |  | (1,012 | )
Provision for loan losses | (1,130 | ) |  | 636 |  |  | 775 |  |  | 629 |  |  | 297 |  |  | 1,207 |
Balance at End of Period | $ | 19,071 |  |  | $ | 13,711 |  |  | $ | 6,869 |  |  | $ | 6,723 |  |  | $ | 1,732 |  |  | $ | 48,106 |
Summary of Allowance for Loan Losses and Recorded Investments | The following tables present the ALL and recorded investments in loans by category as of the periods presented:
| March 31, 2016
| Allowance for Loan Losses |  | Portfolio Loans
(dollars in thousands) | Individually Evaluated for Impairment |  | Collectively Evaluated for Impairment |  | Total |  |  | Individually Evaluated for Impairment |  | Collectively Evaluated for Impairment |  | Total(1) |
Commercial real estate | $ | — |  | $ | 15,266 |  | $ | 15,266 |  |  | $ | 18,505 |  | $ | 2,241,726 |  | $ | 2,260,231 |
Commercial and industrial | 2,027 |  | 12,713 |  | 14,740 |  |  | 18,628 |  | 1,315,491 |  | 1,334,119 |
Commercial construction | 154 |  | 10,671 |  | 10,825 |  |  | 11,888 |  | 367,405 |  | 379,293 |
Consumer real estate | 30 |  | 8,231 |  | 8,261 |  |  | 11,152 |  | 1,115,764 |  | 1,126,916 |
Other consumer | 2 |  | 1,253 |  | 1,255 |  |  | 29 |  | 76,160 |  | 76,189 |
Total | $ | 2,213 |  | $ | 48,134 |  | $ | 50,347 |  |  | $ | 60,202 |  | $ | 5,116,546 |  | $ | 5,176,748 |
(1)Includes acquired loans.
| December 31, 2015
| Allowance for Loan Losses |  | Portfolio Loans
(dollars in thousands) | Individually Evaluated for Impairment |  | Collectively Evaluated for Impairment |  | Total |  |  | Individually Evaluated for Impairment |  | Collectively Evaluated for Impairment |  | Total(1) |
Commercial real estate | $ | — |  | $ | 15,043 |  | $ | 15,043 |  |  | $ | 12,661 |  | $ | 2,153,942 |  | $ | 2,166,603 |
Commercial and industrial | — |  | 10,853 |  | 10,853 |  |  | 14,417 |  | 1,242,413 |  | 1,256,830 |
Commercial construction | 3 |  | 12,622 |  | 12,625 |  |  | 11,498 |  | 401,946 |  | 413,444 |
Consumer real estate | 32 |  | 8,368 |  | 8,400 |  |  | 6,961 |  | 1,109,835 |  | 1,116,796 |
Other consumer | 2 |  | 1,224 |  | 1,226 |  |  | 113 |  | 73,826 |  | 73,939 |
Total | $ | 37 |  | $ | 48,110 |  | $ | 48,147 |  |  | $ | 45,650 |  | $ | 4,981,962 |  | $ | 5,027,612 |
(1)Includes acquired loans.

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- Definition Tabular disclosure of financing receivables by credit quality indicator. The credit quality indicator is a statistic about the credit quality of financing receivables. Examples include, but not limited to, consumer credit risk scores, credit-rating-agency ratings, an entity's internal credit risk grades, loan-to-value ratios, collateral, collection experience and other internal metrics. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 55 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=32702940&loc=SL6953803-111525 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953659-111524 + Details
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- Definition Tabular disclosure of financing receivables that are past due but not impaired, financing receivables that are 90 days past due and still accruing, and financing receivables on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524 + Details
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