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Loans and Loans Held for Sale - Summary of Nonperforming Assets (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
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Nonperforming Assets |  |
Nonaccrual loans | $ 8,218 stba_FinancingReceivableRecordedInvestmentNonPerforming | $ 7,021 stba_FinancingReceivableRecordedInvestmentNonPerforming
Nonaccrual TDRs | 9,916 stba_FinancingReceivableRecordedInvestmentNonaccrualTroubleDebtRestructured | 5,436 stba_FinancingReceivableRecordedInvestmentNonaccrualTroubleDebtRestructured
Total nonaccrual loans | 18,134 us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus | 12,457 us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus
OREO | 1,294 us-gaap_OtherRealEstate | 166 us-gaap_OtherRealEstate
Total Nonperforming Assets | $ 19,428 stba_NetNonperformingAssets | $ 12,623 stba_NetNonperformingAssets

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- Definition Financing receivable recorded investment nonaccrual trouble debt restructured. + References No definition available. + Details
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- Definition Financing receivable recorded investment non performing. + References No definition available. + Details
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- Definition Net nonperforming assets. + References No definition available. + Details
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- Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524 + Details
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- Definition Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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