XML 36 R26.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Allowance for Loan Losses (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2017
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, 2017
(dollars in thousands) | Current |  | 30-59 Days Past Due |  | 60-89 Days Past Due |  | Nonaccrual |  | Total Past Due |  | Total Loans
Commercial real estate | $ | 2,605,369 |  |  | $ | 664 |  |  | $ | 74 |  |  | $ | 8,617 |  |  | $ | 9,355 |  |  | $ | 2,614,724 |
Commercial and industrial | 1,397,625 |  |  | 2,245 |  |  | 548 |  |  | 21,879 |  |  | 24,672 |  |  | 1,422,297 |
Commercial construction | 451,001 |  |  | 452 |  |  | — |  |  | 3,758 |  |  | 4,210 |  |  | 455,211 |
Residential mortgage | 690,524 |  |  | 1,584 |  |  | 284 |  |  | 8,218 |  |  | 10,086 |  |  | 700,610 |
Home equity | 474,824 |  |  | 1,007 |  |  | 87 |  |  | 3,484 |  |  | 4,578 |  |  | 479,402 |
Installment and other consumer | 70,006 |  |  | 122 |  |  | 55 |  |  | 36 |  |  | 213 |  |  | 70,219 |
Consumer construction | 4,363 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4,363 |
Loans held for sale | 14,355 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 14,355 |
Total | $ | 5,708,067 |  |  | $ | 6,074 |  |  | $ | 1,048 |  |  | $ | 45,992 |  |  | $ | 53,114 |  |  | $ | 5,761,181 |
| December 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 | $ | 2,479,513 |  |  | $ | 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 |
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, 2017
(dollars in thousands) | Commercial Real Estate | % of Total |  | Commercial and Industrial | % of Total |  | Commercial Construction | % of Total |  | Total | % of Total
Pass | $ | 2,527,128 |  | 96.7 | % |  | $ | 1,320,246 |  | 92.8 | % |  | $ | 431,074 |  | 94.7 | % |  | $ | 4,278,448 |  | 95.2 | %
Special mention | 55,256 |  | 2.1 | % |  | 49,271 |  | 3.5 | % |  | 14,592 |  | 3.2 | % |  | 119,119 |  | 2.7 | %
Substandard | 32,340 |  | 1.2 | % |  | 52,780 |  | 3.7 | % |  | 9,545 |  | 2.1 | % |  | 94,665 |  | 2.1 | %
Total | $ | 2,614,724 |  | 100.0 | % |  | $ | 1,422,297 |  | 100.0 | % |  | $ | 455,211 |  | 100.0 | % |  | $ | 4,492,232 |  | 100.0 | %
| 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 | %
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, 2017
(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 | $ | 692,392 |  | 98.8 | % |  | $ | 475,918 |  | 99.3 | % |  | $ | 70,183 |  | 99.9 | % |  | $ | 4,363 |  | 100.0 | % |  | $ | 1,242,856 |  | 99.1 | %
Nonperforming | 8,218 |  | 1.2 | % |  | 3,484 |  | 0.7 | % |  | 36 |  | 0.1 | % |  | — |  | — | % |  | 11,738 |  | 0.9 | %
Total | $ | 700,610 |  | 100.0 | % |  | $ | 479,402 |  | 100.0 | % |  | $ | 70,219 |  | 100.0 | % |  | $ | 4,363 |  | 100.0 | % |  | $ | 1,254,594 |  | 100.0 | %
| 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 | %
Investments in Loans Considered to be Impaired and Related Information on Impaired Loans | The following table summarizes investments in loans considered to be impaired and related information on those impaired loans as of the dates presented:
| March 31, 2017 |  | December 31, 2016
(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 | 9,929 |  |  | 11,520 |  |  | 3,541 |  |  | 964 |  |  | 2,433 |  |  | 771 |
Commercial construction | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Consumer real estate | 25 |  |  | 25 |  |  | 25 |  |  | 26 |  |  | 26 |  |  | 26 |
Other consumer | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |
Total with a Related Allowance Recorded | 9,955 |  |  | 11,546 |  |  | 3,567 |  |  | 991 |  |  | 2,460 |  |  | 798 |
Without a related allowance recorded: |  |  |  |  |  |  |  |  |  |  |
Commercial real estate | 8,429 |  |  | 9,773 |  |  | — |  |  | 16,352 |  |  | 17,654 |  |  | — |
Commercial and industrial | 11,115 |  |  | 11,651 |  |  | — |  |  | 5,902 |  |  | 7,699 |  |  | — |
Commercial construction | 5,903 |  |  | 9,773 |  |  | — |  |  | 6,613 |  |  | 10,306 |  |  | — |
Consumer real estate | 11,335 |  |  | 12,185 |  |  | — |  |  | 12,053 |  |  | 12,849 |  |  | — |
Other consumer | 21 |  |  | 23 |  |  | — |  |  | 24 |  |  | 31 |  |  | — |
Total without a Related Allowance Recorded | 36,803 |  |  | 43,405 |  |  | — |  |  | 40,944 |  |  | 48,539 |  |  | — |
Total: |  |  |  |  |  |  |  |  |  |  |
Commercial real estate | 8,429 |  |  | 9,773 |  |  | — |  |  | 16,352 |  |  | 17,654 |  |  | — |
Commercial and industrial | 21,044 |  |  | 23,171 |  |  | 3,541 |  |  | 6,866 |  |  | 10,132 |  |  | 771 |
Commercial construction | 5,903 |  |  | 9,773 |  |  | — |  |  | 6,613 |  |  | 10,306 |  |  | — |
Consumer real estate | 11,360 |  |  | 12,210 |  |  | 25 |  |  | 12,079 |  |  | 12,875 |  |  | 26 |
Other consumer | 22 |  |  | 24 |  |  | 1 |  |  | 25 |  |  | 32 |  |  | 1 |
Total | $ | 46,758 |  |  | $ | 54,951 |  |  | $ | 3,567 |  |  | $ | 41,935 |  |  | $ | 50,999 |  |  | $ | 798 |
The following table summarizes average recorded investment in and interest income recognized on loans considered to be impaired for the periods presented:
| Three Months Ended
| March 31, 2017 |  | March 31, 2016
(dollars in thousands) | Average Recorded Investment |  | Interest Income Recognized |  | Average Recorded Investment |  | Interest Income Recognized
With a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Commercial and industrial | 10,008 |  |  | 72 |  |  | 5,382 |  |  | 32 |
Commercial construction | — |  |  | — |  |  | 1,117 |  |  | 6 |
Consumer real estate | 26 |  |  | — |  |  | 115 |  |  | 2 |
Other consumer | 1 |  |  | — |  |  | 2 |  |  | — |
Total with a Related Allowance Recorded | 10,035 |  |  | 72 |  |  | 6,616 |  |  | 40 |
Without a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | 8,581 |  |  | 33 |  |  | 18,605 |  |  | 199 |
Commercial and industrial | 11,410 |  |  | 43 |  |  | 15,513 |  |  | 149 |
Commercial construction | 6,239 |  |  | 37 |  |  | 10,782 |  |  | 64 |
Consumer real estate | 11,692 |  |  | 129 |  |  | 11,102 |  |  | 135 |
Other consumer | 22 |  |  | — |  |  | 26 |  |  | — |
Total without a Related Allowance Recorded | 37,944 |  |  | 242 |  |  | 56,028 |  |  | 547 |
Total: |  |  |  |  |  |  |
Commercial real estate | 8,581 |  |  | 33 |  |  | 18,605 |  |  | 199 |
Commercial and industrial | 21,418 |  |  | 115 |  |  | 20,895 |  |  | 181 |
Commercial construction | 6,239 |  |  | 37 |  |  | 11,899 |  |  | 70 |
Consumer real estate | 11,718 |  |  | 129 |  |  | 11,217 |  |  | 137 |
Other consumer | 23 |  |  | — |  |  | 28 |  |  | — |
Total | $ | 47,979 |  |  | $ | 314 |  |  | $ | 62,644 |  |  | $ | 587 |
Summary of Allowance for Loan Losses | The following tables detail activity in the ALL for the periods presented:
| Three Months Ended March 31, 2017
(dollars in thousands) | Commercial Real Estate |  |  | Commercial and Industrial |  |  | Commercial Construction |  |  | Consumer Real Estate |  |  | Other Consumer |  |  | Total Loans |
Balance at beginning of period | $ | 19,976 |  |  | $ | 10,810 |  |  | $ | 13,999 |  |  | $ | 6,095 |  |  | $ | 1,895 |  |  | $ | 52,775 |
Charge-offs | (390 | ) |  | (715 | ) |  | (644 | ) |  | (759 | ) |  | (434 | ) |  | (2,942 | )
Recoveries | 78 |  |  | 187 |  |  | 256 |  |  | 103 |  |  | 176 |  |  | 800 |
Net (Charge-offs)/ Recoveries | (312 | ) |  | (528 | ) |  | (388 | ) |  | (656 | ) |  | (258 | ) |  | (2,142 | )
Provision for loan losses | 906 |  |  | 2,962 |  |  | 491 |  |  | 517 |  |  | 307 |  |  | 5,183 |
Balance at End of Period | $ | 20,570 |  |  | $ | 13,244 |  |  | $ | 14,102 |  |  | $ | 5,956 |  |  | $ | 1,944 |  |  | $ | 55,816 |
| 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 |
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, 2017
| 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 | $ | — |  |  | $ | 20,570 |  |  | $ | 20,570 |  |  | $ | 8,429 |  |  | $ | 2,606,295 |  |  | $ | 2,614,724 |
Commercial and industrial | 3,541 |  |  | 9,703 |  |  | 13,244 |  |  | 21,044 |  |  | 1,401,253 |  |  | 1,422,297 |
Commercial construction | — |  |  | 14,102 |  |  | 14,102 |  |  | 5,903 |  |  | 449,308 |  |  | 455,211 |
Consumer real estate | 25 |  |  | 5,931 |  |  | 5,956 |  |  | 11,360 |  |  | 1,173,015 |  |  | 1,184,375 |
Other consumer | 1 |  |  | 1,943 |  |  | 1,944 |  |  | 22 |  |  | 70,197 |  |  | 70,219 |
Total | $ | 3,567 |  |  | $ | 52,249 |  |  | $ | 55,816 |  |  | $ | 46,758 |  |  | $ | 5,700,068 |  |  | $ | 5,746,826 |
| 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 |

X
- Definition Allowance for loan losses and portfolio loans. + References No definition available. + Details
Name: | stba_AllowanceForLoanLossesAndPortfolioLoansTableTableTextBlock
Namespace Prefix: | stba_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of change in fair value of commercial consumer loans. + References No definition available. + Details
Name: | stba_ScheduleOfChangeInFairValueOfCommercialConsumerLoansTableTableTextBlock
Namespace Prefix: | stba_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of performing non performing loans by category. + References No definition available. + Details
Name: | stba_ScheduleOfPerformingNonPerformingLoansByCategoryTableTableTextBlock
Namespace Prefix: | stba_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of impaired financing receivables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_PastDueFinancingReceivablesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ReceivablesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration