XML 59 R49.htm IDEA: XBRL DOCUMENT
v3.19.2

Loans and Loans Held for Sale - Composition of Loans (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Composition of the loans |  |
Portfolio loans, net of unearned income | $ 6,033,200 | $ 5,946,648
Loans held for sale | 8,135 | 2,371
Total Loans | 6,041,335 | 5,949,019
Commercial real estate |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 2,906,895 | 2,921,832
Total Loans | 2,906,895 | 2,921,832
Commercial and industrial |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 1,559,727 | 1,493,416
Total Loans | 1,559,727 | 1,493,416
Commercial construction |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 267,203 | 257,197
Total Loans | 267,203 | 257,197
Residential mortgage |  |
Composition of the loans |  |
Total Loans | 751,355 | 726,679
Home equity |  |
Composition of the loans |  |
Total Loans | 464,195 | 471,562
Installment and other consumer |  |
Composition of the loans |  |
Total Loans | 72,041 | 67,546
Consumer construction |  |
Composition of the loans |  |
Total Loans | 11,784 | 8,416
Commercial |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 4,733,825 | 4,672,445
Commercial | Commercial real estate |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 2,906,895 | 2,921,832
Commercial | Commercial and industrial |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 1,559,727 | 1,493,416
Commercial | Commercial construction |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 267,203 | 257,197
Consumer |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 1,299,375 | 1,274,203
Consumer | Residential mortgage |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 751,355 | 726,679
Consumer | Home equity |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 464,195 | 471,562
Consumer | Installment and other consumer |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | 72,041 | 67,546
Consumer | Consumer construction |  |
Composition of the loans |  |
Portfolio loans, net of unearned income | $ 11,784 | $ 8,416

X
- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524 + Details
Name: | us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
Name: | us-gaap_NotesReceivableNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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=us-gaap_ResidentialMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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