XML 59 R43.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Allowance for Loan Losses (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2015
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, 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 |
| December 31, 2014
(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 | $ | 1,674,930 |  | $ | 2,548 |  | $ | 323 |  | $ | 4,435 |  | $ | 7,306 |  | $ | 1,682,236 |
Commercial and industrial | 991,136 |  | 1,227 |  | 153 |  | 1,622 |  | 3,002 |  | 994,138 |
Commercial construction | 214,174 |  | — |  | — |  | 1,974 |  | 1,974 |  | 216,148 |
Residential mortgage | 485,465 |  | 565 |  | 1,220 |  | 2,336 |  | 4,121 |  | 489,586 |
Home equity | 414,303 |  | 1,756 |  | 445 |  | 2,059 |  | 4,260 |  | 418,563 |
Installment and other consumer | 65,111 |  | 352 |  | 73 |  | 31 |  | 456 |  | 65,567 |
Consumer construction | 2,508 |  | — |  | — |  | — |  | — |  | 2,508 |
Loans held for sale | 2,970 |  | — |  | — |  | — |  | — |  | 2,970 |
Total | $ | 3,850,597 |  | $ | 6,448 |  | $ | 2,214 |  | $ | 12,457 |  | $ | 21,119 |  | $ | 3,871,716 |
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, 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 | %
| December 31, 2014
(dollars in thousands) | Commercial Real Estate |  | % of Total |  |  | Commercial and Industrial |  | % of Total |  |  | Commercial Construction |  | % of Total |  |  | Total |  | % of Total |
Pass | $ | 1,635,132 |  | 97.2 | % |  | $ | 948,663 |  | 95.4 | % |  | $ | 196,520 |  | 90.9 | % |  | $ | 2,780,315 |  | 96.1 | %
Special mention | 23,597 |  | 1.4 | % |  | 30,357 |  | 3.1 | % |  | 12,014 |  | 5.6 | % |  | 65,968 |  | 2.3 | %
Substandard | 23,507 |  | 1.4 | % |  | 15,118 |  | 1.5 | % |  | 7,614 |  | 3.5 | % |  | 46,239 |  | 1.6 | %
Total | $ | 1,682,236 |  | 100.0 | % |  | $ | 994,138 |  | 100.0 | % |  | $ | 216,148 |  | 100.0 | % |  | $ | 2,892,522 |  | 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, 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 | %
| December 31, 2014
(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 | $ | 487,250 |  | 99.5 | % | $ | 416,504 |  | 99.5 | % | $ | 65,536 |  | 99.9 | % | $ | 2,508 |  | 100.0 | % | $ | 971,798 |  | 99.5 | %
Nonperforming | 2,336 |  | 0.5 | % | 2,059 |  | 0.5 | % | 31 |  | 0.1 | % | — |  | — | % | 4,426 |  | 0.5 | %
Total | $ | 489,586 |  | 100.0 | % | $ | 418,563 |  | 100.0 | % | $ | 65,567 |  | 100.0 | % | $ | 2,508 |  | 100.0 | % | $ | 976,224 |  | 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 for the years presented:
| For the Year Ended
| December 31, 2015 |  | December 31, 2014
(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 | — |  | — |  |  | — |  | — |
Commercial construction | 834 |  | — |  |  | — |  | — |
Consumer real estate | 120 |  | 7 |  |  | 48 |  | 4 |
Other consumer | 2 |  | — |  |  | 24 |  | 2 |
Total with a Related Allowance Recorded | 956 |  | 7 |  |  | 72 |  | 6 |
Without a related allowance recorded: |  |  |  |  |
Commercial real estate | 14,622 |  | 597 |  |  | 20,504 |  | 684 |
Commercial and industrial | 14,416 |  | 450 |  |  | 9,246 |  | 241 |
Commercial construction | 10,581 |  | 329 |  |  | 8,145 |  | 227 |
Consumer real estate | 6,902 |  | 364 |  |  | 7,027 |  | 396 |
Other consumer | 117 |  | 1 |  |  | 56 |  | 2 |
Total without a Related Allowance Recorded | 46,638 |  | 1,741 |  |  | 44,978 |  | 1,550 |
Total: |  |  |  |  |
Commercial real estate | 14,622 |  | 597 |  |  | 20,504 |  | 684 |
Commercial and industrial | 14,416 |  | 450 |  |  | 9,246 |  | 241 |
Commercial construction | 11,415 |  | 329 |  |  | 8,145 |  | 227 |
Consumer real estate | 7,022 |  | 371 |  |  | 7,075 |  | 400 |
Other consumer | 119 |  | 1 |  |  | 80 |  | 4 |
Total | $ | 47,594 |  | $ | 1,748 |  |  | $ | 45,050 |  | $ | 1,556 |
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, 2015 |  | December 31, 2014
(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 | — |  | — |  | — |  |  | — |  | — |  | — |
Commercial construction | 500 |  | 1,350 |  | 3 |  |  | — |  | — |  | — |
Consumer real estate | 116 |  | 116 |  | 32 |  |  | 43 |  | 43 |  | 43 |
Other consumer | 2 |  | 2 |  | 2 |  |  | 20 |  | 20 |  | 11 |
Total with a Related Allowance Recorded | 618 |  | 1,468 |  | 37 |  |  | 63 |  | 63 |  | 54 |
Without a related allowance recorded: |  |  |  |  |  |  |
Commercial real estate | 12,661 |  | 13,157 |  | — |  |  | 19,890 |  | 25,262 |  | — |
Commercial and industrial | 14,417 |  | 15,220 |  | — |  |  | 9,218 |  | 9,449 |  | — |
Commercial construction | 10,998 |  | 14,200 |  | — |  |  | 7,605 |  | 11,293 |  | — |
Consumer real estate | 6,845 |  | 7,521 |  | — |  |  | 7,159 |  | 7,733 |  | — |
Other consumer | 111 |  | 188 |  | — |  |  | 42 |  | 48 |  | — |
Total without a Related Allowance Recorded | 45,032 |  | 50,286 |  | — |  |  | 43,914 |  | 53,785 |  | — |
Total: |  |  |  |  |  |  |
Commercial real estate | 12,661 |  | 13,157 |  | — |  |  | 19,890 |  | 25,262 |  | — |
Commercial and industrial | 14,417 |  | 15,220 |  | — |  |  | 9,218 |  | 9,449 |  | — |
Commercial construction | 11,498 |  | 15,550 |  | 3 |  |  | 7,605 |  | 11,293 |  | — |
Consumer real estate | 6,961 |  | 7,637 |  | 32 |  |  | 7,202 |  | 7,776 |  | 43 |
Other consumer | 113 |  | 190 |  | 2 |  |  | 62 |  | 68 |  | 11 |
Total | $ | 45,650 |  | $ | 51,754 |  | $ | 37 |  |  | $ | 43,977 |  | $ | 53,848 |  | $ | 54 |
Summary of Allowance for Loan Losses | The following tables detail activity in the ALL for the periods presented:
| 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 |
| 2014
(dollars in thousands) | Commercial Real Estate |  | Commercial and Industrial |  | Commercial Construction |  | Consumer Real Estate |  | Other Consumer |  | Total Loans |
Balance at beginning of year | $ | 18,921 |  | $ | 14,433 |  | $ | 5,374 |  | $ | 6,362 |  | $ | 1,165 |  | $ | 46,255 |
Charge-offs | (2,041 | ) | (1,267 | ) | (712 | ) | (1,200 | ) | (1,133 | ) | (6,353 | )
Recoveries | 1,798 |  | 3,647 |  | 146 |  | 350 |  | 353 |  | 6,294 |
Net (Charge-offs)/ Recoveries | (243 | ) | 2,380 |  | (566 | ) | (850 | ) | (780 | ) | (59 | )
Provision for loan losses | 1,486 |  | (3,145 | ) | 1,285 |  | 821 |  | 1,268 |  | 1,715 |
Balance at End of Year | $ | 20,164 |  | $ | 13,668 |  | $ | 6,093 |  | $ | 6,333 |  | $ | 1,653 |  | $ | 47,911 |
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:
| 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 |
| 2014
| 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 | $ | — |  | $ | 20,164 |  | $ | 20,164 |  | $ | 19,890 |  | $ | 1,662,346 |  | $ | 1,682,236 |
Commercial and industrial | — |  | 13,668 |  | 13,668 |  | 9,218 |  | 984,920 |  | 994,138 |
Commercial construction | — |  | 6,093 |  | 6,093 |  | 7,605 |  | 208,543 |  | 216,148 |
Consumer real estate | 43 |  | 6,290 |  | 6,333 |  | 7,202 |  | 903,455 |  | 910,657 |
Other consumer | 11 |  | 1,642 |  | 1,653 |  | 62 |  | 65,505 |  | 65,567 |
Total | $ | 54 |  | $ | 47,857 |  | $ | 47,911 |  | $ | 43,977 |  | $ | 3,824,769 |  | $ | 3,868,746 |

X
- Definition Allowance for loan losses and portfolio loans. + References No definition available. + Details
Name: | stba_AllowanceForLoanLossesAndPortfolioLoansTableTextBlock
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_ScheduleOfChangeInFairValueOfCommercialConsumerLoansTableTextBlock
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_ScheduleOfPerformingNonPerformingLoansByCategoryTableTextBlock
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=49124121&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=49124121&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=49124121&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=49124121&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