XML 95 R83.htm IDEA: XBRL DOCUMENT
v3.22.4

Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | $ 66,291 | $ 146,774
End of Period Nonaccrual | 19,052 | 66,291
Nonaccrual With No Related Allowance | 6,582 | 37,469
Interest Income Recognized on Nonaccrual | 1,385 | 1,128
Commercial | Commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 31,488 | 101,070
End of Period Nonaccrual | 7,100 | 31,488
Nonaccrual With No Related Allowance | 5,649 | 28,046
Interest Income Recognized on Nonaccrual | 580 | 158
Commercial | Commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 15,239 | 16,985
End of Period Nonaccrual | 283 | 15,239
Nonaccrual With No Related Allowance | 0 | 5,707
Interest Income Recognized on Nonaccrual | 148 | 74
Commercial | Commercial construction |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 2,471 | 384
End of Period Nonaccrual | 384 | 2,471
Nonaccrual With No Related Allowance | 0 | 2,020
Interest Income Recognized on Nonaccrual | 171 | (28)
Commercial | Business banking |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 9,641 | 17,122
End of Period Nonaccrual | 4,490 | 9,641
Nonaccrual With No Related Allowance | 933 | 1,696
Interest Income Recognized on Nonaccrual | 228 | 427
Consumer | Consumer real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 7,294 | 11,117
End of Period Nonaccrual | 6,526 | 7,294
Nonaccrual With No Related Allowance | 0 | 0
Interest Income Recognized on Nonaccrual | 257 | 496
Consumer | Other consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 158 | 96
End of Period Nonaccrual | 269 | 158
Nonaccrual With No Related Allowance | 0 | 0
Interest Income Recognized on Nonaccrual | $ 1 | $ 1

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of interest income on financing receivable on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableNonaccrualInterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

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=stba_OtherConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |