XML 87 R65.htm IDEA: XBRL DOCUMENT
v3.25.4

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans Modified Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Receivables [Abstract] |  |
Commitments to lend additional funds to borrowers | $ 335 |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 3,109 | $ 15,132
Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Term Extension |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 2,826 | 3,686
Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 5,633
Principal Forgiveness |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Combination Term Extension and Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Combination Term Extension and Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 283 | 5,813
Commercial and industrial |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 2,935 | 3,260
Commercial and industrial | Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Commercial and industrial | Term Extension |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 2,652 | 1,091
Commercial and industrial | Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 780
Commercial and industrial | Principal Forgiveness |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Commercial and industrial | Combination Term Extension and Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Commercial and industrial | Combination Term Extension and Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 283 | 1,389
Real estate | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 4,507
Real estate | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 174 | 4,989
Real estate | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 1,964
Real estate | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 412
Real estate | Interest Rate Reduction | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Interest Rate Reduction | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Interest Rate Reduction | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Interest Rate Reduction | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Term Extension | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Term Extension | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 174 | 1,103
Real estate | Term Extension | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 1,080
Real estate | Term Extension | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 412
Real estate | Payment Delay | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 3,040
Real estate | Payment Delay | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 1,428
Real estate | Payment Delay | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 385
Real estate | Payment Delay | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Principal Forgiveness | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Principal Forgiveness | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Principal Forgiveness | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Principal Forgiveness | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Combination Term Extension and Payment Delay | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Combination Term Extension and Payment Delay | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Combination Term Extension and Payment Delay | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Combination Term Extension and Payment Delay | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Real estate | Combination Term Extension and Interest Rate Reduction | Commercial real estate (including multi-family residential) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 1,467
Real estate | Combination Term Extension and Interest Rate Reduction | Commercial real estate construction and land development |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 2,458
Real estate | Combination Term Extension and Interest Rate Reduction | 1-4 family residential (including home equity) |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 499
Real estate | Combination Term Extension and Interest Rate Reduction | Residential construction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Term Extension |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Principal Forgiveness |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Combination Term Extension and Payment Delay |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | 0 | 0
Consumer and other | Combination Term Extension and Interest Rate Reduction |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Financing receivable, modified period | $ 0 | $ 0

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://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481628/310-20-40-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-2 + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481746/310-40-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 36 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-36 + Details
Name: | us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_ContractualInterestRateReductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_PaymentDeferralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_PrincipalForgivenessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=stel_TermExtensionAndPrincipalForgivenessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=stel_TermExtensionAndInterestRateReductionMember
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=stel_RealEstatePorfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=stel_ResidentialConstructionMember
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: |