XML 94 R80.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 893,015 | $ 1,117,436
Year two | 1,134,650 | 1,320,936
Year three | 1,191,528 | 1,094,225
Year four | 897,782 | 503,703
Year five | 421,743 | 645,502
More than five years | 1,885,462 | 1,650,211
Revolving | 1,284,808 | 1,292,135
Revolving-Term | 33,970 | 29,193
Total | 7,742,958 | 7,653,341
Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 893,015 | 1,117,436
Year two | 1,131,744 | 1,320,560
Year three | 1,190,371 | 1,094,056
Year four | 896,661 | 502,950
Year five | 418,574 | 640,393
More than five years | 1,877,620 | 1,635,979
Revolving | 1,274,906 | 1,291,683
Revolving-Term | 32,130 | 27,337
Total | 7,715,021 | 7,630,394
Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 2,906 | 376
Year three | 1,157 | 169
Year four | 1,121 | 753
Year five | 3,169 | 5,109
More than five years | 7,842 | 14,232
Revolving | 9,902 | 452
Revolving-Term | 1,840 | 1,856
Total | 27,937 | 22,947
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 278,187 | 276,677
Year two | 289,081 | 324,469
Year three | 363,529 | 439,308
Year four | 415,621 | 240,256
Year five | 215,632 | 419,371
More than five years | 1,110,490 | 926,636
Revolving | 35,991 | 32,418
Revolving-Term | 0 | 0
Total | 2,708,531 | 2,659,135
Commercial Loans | Commercial real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 278,187 | 276,677
Year two | 289,081 | 324,469
Year three | 362,544 | 439,308
Year four | 415,621 | 240,256
Year five | 214,589 | 419,371
More than five years | 1,109,290 | 920,316
Revolving | 35,991 | 32,418
Revolving-Term | 0 | 0
Total | 2,705,303 | 2,652,815
Commercial Loans | Commercial real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 985 | 0
Year four | 0 | 0
Year five | 1,043 | 0
More than five years | 1,200 | 6,320
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 3,228 | 6,320
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 120,143 | 171,861
Year two | 148,100 | 231,978
Year three | 195,756 | 210,636
Year four | 152,971 | 54,696
Year five | 31,312 | 52,858
More than five years | 197,426 | 193,905
Revolving | 505,929 | 520,249
Revolving-Term | 0 | 0
Total | 1,351,637 | 1,436,183
Commercial Loans | Commercial and industrial | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 120,143 | 171,861
Year two | 148,070 | 231,978
Year three | 195,584 | 210,636
Year four | 151,976 | 54,696
Year five | 30,103 | 52,858
More than five years | 197,426 | 193,257
Revolving | 497,162 | 520,019
Revolving-Term | 0 | 0
Total | 1,340,464 | 1,435,305
Commercial Loans | Commercial and industrial | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 30 | 0
Year three | 172 | 0
Year four | 995 | 0
Year five | 1,209 | 0
More than five years | 0 | 648
Revolving | 8,767 | 230
Revolving-Term | 0 | 0
Total | 11,173 | 878
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 119,355 | 75,596
Year two | 121,816 | 154,456
Year three | 73,851 | 82,313
Year four | 14,911 | 14,845
Year five | 884 | 4,727
More than five years | 2,139 | 4,438
Revolving | 8,310 | 14,208
Revolving-Term | 0 | 0
Total | 341,266 | 350,583
Commercial Loans | Commercial construction | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 119,355 | 75,596
Year two | 121,816 | 154,456
Year three | 73,851 | 82,313
Year four | 14,911 | 14,845
Year five | 884 | 151
More than five years | 2,139 | 4,054
Revolving | 8,310 | 14,208
Revolving-Term | 0 | 0
Total | 341,266 | 345,623
Commercial Loans | Commercial construction | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 4,576
More than five years | 0 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 0 | 4,960
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 149,624 | 270,129
Year two | 233,041 | 262,606
Year three | 226,654 | 207,611
Year four | 177,683 | 88,018
Year five | 76,643 | 99,574
More than five years | 345,327 | 334,766
Revolving | 92,981 | 96,754
Revolving-Term | 1,305 | 1,307
Total | 1,303,258 | 1,360,765
Commercial Loans | Business banking | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 149,624 | 270,129
Year two | 232,649 | 262,606
Year three | 226,654 | 207,611
Year four | 177,683 | 87,979
Year five | 76,344 | 99,354
More than five years | 343,064 | 330,902
Revolving | 92,981 | 96,754
Revolving-Term | 1,271 | 1,283
Total | 1,300,270 | 1,356,618
Commercial Loans | Business banking | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 392 | 0
Year three | 0 | 0
Year four | 0 | 39
Year five | 299 | 220
More than five years | 2,263 | 3,864
Revolving | 0 | 0
Revolving-Term | 34 | 24
Total | 2,988 | 4,147
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 217,250 | 311,887
Year two | 335,763 | 335,462
Year three | 324,389 | 147,850
Year four | 133,347 | 102,041
Year five | 95,504 | 67,890
More than five years | 229,462 | 189,794
Revolving | 570,558 | 552,080
Revolving-Term | 27,236 | 24,774
Total | 1,933,509 | 1,731,778
Consumer Loans | Consumer real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 217,250 | 311,887
Year two | 333,279 | 335,086
Year three | 324,389 | 147,689
Year four | 133,224 | 101,518
Year five | 94,971 | 67,577
More than five years | 225,225 | 186,909
Revolving | 569,423 | 551,858
Revolving-Term | 25,430 | 22,942
Total | 1,923,191 | 1,725,466
Consumer Loans | Consumer real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 2,484 | 376
Year three | 0 | 161
Year four | 123 | 523
Year five | 533 | 313
More than five years | 4,237 | 2,885
Revolving | 1,135 | 222
Revolving-Term | 1,806 | 1,832
Total | 10,318 | 6,312
Consumer Loans | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 8,456 | 11,286
Year two | 6,849 | 11,965
Year three | 7,349 | 6,507
Year four | 3,249 | 3,847
Year five | 1,768 | 1,082
More than five years | 618 | 672
Revolving | 71,039 | 76,426
Revolving-Term | 5,429 | 3,112
Total | 104,757 | 114,897
Consumer Loans | Other consumer | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 8,456 | 11,286
Year two | 6,849 | 11,965
Year three | 7,349 | 6,499
Year four | 3,246 | 3,656
Year five | 1,683 | 1,082
More than five years | 476 | 541
Revolving | 71,039 | 76,426
Revolving-Term | 5,429 | 3,112
Total | 104,527 | 114,567
Consumer Loans | Other consumer | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 8
Year four | 3 | 191
Year five | 85 | 0
More than five years | 142 | 131
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 230 | $ 330

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable that can be withdrawn, repaid, and redrawn. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestRevolving
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of revolving financing receivable converted to term loan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 29 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-29 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_PerformingFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_NonperformingFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_CommercialAndIndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_BusinessBankingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stba_ConsumerRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |