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Allowance for Loan Losses (Tables) | 12 Months Ended
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Dec. 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:
| December 31, 2016
(dollars in thousands) | Current |  | 30-59 Days Past Due |  | 60-89 Days Past Due |  | Non- performing |  | Total Past Due Loans |  | Total Loans |
Commercial real estate | $ | 2,479,513 |  | $ | 2,032 |  | $ | 759 |  | $ | 16,172 |  | $ | 18,963 |  | $ | 2,498,476 |
Commercial and industrial | 1,391,475 |  | 1,061 |  | 428 |  | 8,071 |  | 9,560 |  | 1,401,035 |
Commercial construction | 450,410 |  | 547 |  | — |  | 4,927 |  | 5,474 |  | 455,884 |
Residential mortgage | 689,635 |  | 1,312 |  | 1,117 |  | 9,918 |  | 12,347 |  | 701,982 |
Home equity | 476,866 |  | 1,470 |  | 509 |  | 3,439 |  | 5,418 |  | 482,284 |
Installment and other consumer | 65,525 |  | 176 |  | 43 |  | 108 |  | 327 |  | 65,852 |
Consumer construction | 5,906 |  | — |  | — |  | — |  | — |  | 5,906 |
Loans held for sale | 3,793 |  | — |  | — |  | — |  | — |  | 3,793 |
Total | $ | 5,563,123 |  | $ | 6,598 |  | $ | 2,856 |  | $ | 42,635 |  | $ | 52,089 |  | $ | 5,615,212 |
| December 31, 2015
(dollars in thousands) | Current |  | 30-59 Days Past Due |  | 60-89 Days Past Due |  | Non- performing |  | Total Past Due Loans |  | 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 |
Total | $ | 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:
| December 31, 2016
(dollars in thousands) | Commercial Real Estate |  | % of Total |  |  | Commercial and Industrial |  | % of Total |  |  | Commercial Construction |  | % of Total |  |  | Total |  | % of Total |
Pass | $ | 2,423,742 |  | 97.0 | % |  | $ | 1,315,507 |  | 93.9 | % |  | $ | 430,472 |  | 94.4 | % |  | $ | 4,169,721 |  | 95.7 | %
Special mention | 33,098 |  | 1.3 | % |  | 40,409 |  | 2.9 | % |  | 14,691 |  | 3.2 | % |  | 88,198 |  | 2.0 | %
Substandard | 41,636 |  | 1.7 | % |  | 45,119 |  | 3.2 | % |  | 10,721 |  | 2.4 | % |  | 97,476 |  | 2.3 | %
Total | $ | 2,498,476 |  | 100.0 | % |  | $ | 1,401,035 |  | 100.0 | % |  | $ | 455,884 |  | 100.0 | % |  | $ | 4,355,395 |  | 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:
| December 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 | $ | 692,064 |  | 98.6 | % | $ | 478,845 |  | 99.3 | % | $ | 65,744 |  | 99.8 | % | $ | 5,906 |  | 100.0 | % | $ | 1,242,559 |  | 98.9 | %
Nonperforming | 9,918 |  | 1.4 | % | 3,439 |  | 0.7 | % | 108 |  | 0.2 | % | — |  | — | % | 13,465 |  | 1.1 | %
Total | $ | 701,982 |  | 100.0 | % | $ | 482,284 |  | 100.0 | % | $ | 65,852 |  | 100.0 | % | $ | 5,906 |  | 100.0 | % | $ | 1,256,024 |  | 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 as of the dates presented:
| December 31, 2016 |  | December 31, 2015
(dollars in thousands) | Recorded Investment |  | Unpaid Principal Balance |  | Related Allowance |  |  | Recorded Investment |  | Unpaid Principal Balance |  | Related Allowance |
With a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | $ | — |  | $ | — |  | $ | — |  |  | $ | — |  | $ | — |  | $ | — |
Commercial and industrial | 964 |  | 2,433 |  | 771 |  |  | — |  | — |  | — |
Commercial construction | — |  | — |  | — |  |  | 500 |  | 1,350 |  | 3 |
Consumer real estate | 26 |  | 26 |  | 26 |  |  | 116 |  | 116 |  | 32 |
Other consumer | 1 |  | 1 |  | 1 |  |  | 2 |  | 2 |  | 2 |
Total with a Related Allowance Recorded | 991 |  | 2,460 |  | 798 |  |  | 618 |  | 1,468 |  | 37 |
Without a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | 16,352 |  | 17,654 |  | — |  |  | 12,661 |  | 13,157 |  | — |
Commercial and industrial | 5,902 |  | 7,699 |  | — |  |  | 14,417 |  | 15,220 |  | — |
Commercial construction | 6,613 |  | 10,306 |  | — |  |  | 10,998 |  | 14,200 |  | — |
Consumer real estate | 12,053 |  | 12,849 |  | — |  |  | 6,845 |  | 7,521 |  | — |
Other consumer | 24 |  | 31 |  | — |  |  | 111 |  | 188 |  | — |
Total without a Related Allowance Recorded | 40,944 |  | 48,539 |  | — |  |  | 45,032 |  | 50,286 |  | — |
Total: |  |  |  |  |  |  |
Commercial real estate | 16,352 |  | 17,654 |  | — |  |  | 12,661 |  | 13,157 |  | — |
Commercial and industrial | 6,866 |  | 10,132 |  | 771 |  |  | 14,417 |  | 15,220 |  | — |
Commercial construction | 6,613 |  | 10,306 |  | — |  |  | 11,498 |  | 15,550 |  | 3 |
Consumer real estate | 12,079 |  | 12,875 |  | 26 |  |  | 6,961 |  | 7,637 |  | 32 |
Other consumer | 25 |  | 32 |  | 1 |  |  | 113 |  | 190 |  | 2 |
Total | $ | 41,935 |  | $ | 50,999 |  | $ | 798 |  |  | $ | 45,650 |  | $ | 51,754 |  | $ | 37 |
The following table summarizes investments in loans considered to be impaired and related information on those impaired loans for the years presented:
| For the Year Ended
| December 31, 2016 |  | December 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 | 17,496 |  | 144 |  |  | 14,622 |  | 597 |
Commercial and industrial | 6,141 |  | 160 |  |  | 14,416 |  | 450 |
Commercial construction | 7,723 |  | 162 |  |  | 10,581 |  | 329 |
Consumer real estate | 11,939 |  | 523 |  |  | 6,902 |  | 364 |
Other consumer | 35 |  | 1 |  |  | 117 |  | 1 |
Total without a Related Allowance Recorded | 43,334 |  | 990 |  |  | 46,638 |  | 1,741 |
With a related allowance recorded: |  |  |  |  |
Commercial real estate | — |  | — |  |  | — |  | — |
Commercial and industrial | 2,438 |  | — |  |  | — |  | — |
Commercial construction | — |  | — |  |  | 834 |  | — |
Consumer real estate | 28 |  | 2 |  |  | 120 |  | 7 |
Other consumer | 2 |  | — |  |  | 2 |  | — |
Total with a Related Allowance Recorded | 2,468 |  | 2 |  |  | 956 |  | 7 |
Total: |  |  |  |  |
Commercial real estate | 17,496 |  | 144 |  |  | 14,622 |  | 597 |
Commercial and industrial | 8,579 |  | 160 |  |  | 14,416 |  | 450 |
Commercial construction | 7,723 |  | 162 |  |  | 11,415 |  | 329 |
Consumer real estate | 11,967 |  | 525 |  |  | 7,022 |  | 371 |
Other consumer | 37 |  | 1 |  |  | 119 |  | 1 |
Total | $ | 45,802 |  | $ | 992 |  |  | $ | 47,594 |  | $ | 1,748 |
Summary of Allowance for Loan Losses | The following tables detail activity in the ALL for the periods presented:
| 2016
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Consumer Real Estate |  | Other Consumer |  | Total Loans |
Balance at beginning of year | $ | 15,043 |  | $ | 10,853 |  | $ | 12,625 |  | $ | 8,400 |  | $ | 1,226 |  | $ | 48,147 |
Charge-offs | (3,114 | ) | (6,810 | ) | (1,877 | ) | (1,657 | ) | (2,103 | ) | (15,561 | )
Recoveries | 692 |  | 722 |  | 21 |  | 433 |  | 356 |  | 2,224 |
Net (Charge-offs) Recoveries | (2,422 | ) | (6,088 | ) | (1,856 | ) | (1,224 | ) | (1,747 | ) | (13,337 | )
Provision for loan losses | 7,355 |  | 6,045 |  | 3,230 |  | (1,081 | ) | 2,416 |  | 17,965 |
Balance at End of Year | $ | 19,976 |  | $ | 10,810 |  | $ | 13,999 |  | $ | 6,095 |  | $ | 1,895 |  | $ | 52,775 |
| 2015
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Consumer Real Estate |  | Other Consumer |  | Total Loans |
Balance at beginning of year | $ | 20,164 |  | $ | 13,668 |  | $ | 6,093 |  | $ | 6,333 |  | $ | 1,653 |  | $ | 47,911 |
Charge-offs | (2,787 | ) | (5,463 | ) | (3,321 | ) | (2,167 | ) | (1,528 | ) | (15,266 | )
Recoveries | 3,545 |  | 605 |  | 143 |  | 495 |  | 326 |  | 5,114 |
Net Recoveries (Charge-offs) | 758 |  | (4,858 | ) | (3,178 | ) | (1,672 | ) | (1,202 | ) | (10,152 | )
Provision for loan losses | (5,879 | ) | 2,043 |  | 9,710 |  | 3,739 |  | 775 |  | 10,388 |
Balance at End of Year | $ | 15,043 |  | $ | 10,853 |  | $ | 12,625 |  | $ | 8,400 |  | $ | 1,226 |  | $ | 48,147 |
Summary of Allowance for Loan Losses and Recorded Investments | The following tables present the ALL and recorded investments in loans by category as of December 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 |
Commercial real estate | $ | — |  | $ | 19,976 |  | $ | 19,976 |  | $ | 16,352 |  | $ | 2,482,124 |  | $ | 2,498,476 |
Commercial and industrial | 771 |  | 10,039 |  | 10,810 |  | 6,866 |  | 1,394,169 |  | 1,401,035 |
Commercial construction | — |  | 13,999 |  | 13,999 |  | 6,613 |  | 449,271 |  | 455,884 |
Consumer real estate | 26 |  | 6,069 |  | 6,095 |  | 12,079 |  | 1,178,093 |  | 1,190,172 |
Other consumer | 1 |  | 1,894 |  | 1,895 |  | 25 |  | 65,827 |  | 65,852 |
Total | $ | 798 |  | $ | 51,977 |  | $ | 52,775 |  | $ | 41,935 |  | $ | 5,569,484 |  | $ | 5,611,419 |
| 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 |
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 |

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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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