XML 60 R48.htm IDEA: XBRL DOCUMENT
v3.25.3

Securities - Schedule of Held-to-maturity, Unrealized Loss on Investments (Details) Unit_Standard_pure_Ln9u5gWpAke2n9G4VdYnFw in Thousands, $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Held-to-maturity: |  |
Less than 12 Months, Fair Value | $ 3,483 |
Less than 12 Months, Gross Unrealized Losses | $ (289) |
Less than 12 Months, Number of Securities | 4 |
12 Months or Greater, Fair Value | $ 106,268 | $ 108,080
12 Months or Greater, Gross Unrealized Losses | $ (13,324) | $ (18,579)
12 Months or Greater, Number of Securities | 51 | 53
Total, Fair Value | $ 109,751 | $ 108,080
Total, Gross Unrealized Losses | $ (13,613) | $ (18,579)
Total, Number of Securities | 55 | 53
U.S. Government-sponsored enterprises (GSEs) |  |
Held-to-maturity: |  |
12 Months or Greater, Fair Value | $ 41,938 | $ 40,777
12 Months or Greater, Gross Unrealized Losses | $ (5,243) | $ (7,335)
12 Months or Greater, Number of Securities | 13 | 13
Total, Fair Value | $ 41,938 | $ 40,777
Total, Gross Unrealized Losses | $ (5,243) | $ (7,335)
Total, Number of Securities | 13 | 13
Municipal securities |  |
Held-to-maturity: |  |
Less than 12 Months, Fair Value | $ 3,483 |
Less than 12 Months, Gross Unrealized Losses | $ (289) |
Less than 12 Months, Number of Securities | 4 |
12 Months or Greater, Fair Value | $ 41,808 | $ 44,615
12 Months or Greater, Gross Unrealized Losses | $ (5,286) | $ (7,037)
12 Months or Greater, Number of Securities | 33 | 35
Total, Fair Value | $ 45,291 | $ 44,615
Total, Gross Unrealized Losses | $ (5,575) | $ (7,037)
Total, Number of Securities | 37 | 35
Mortgage-backed securities (GSEs) |  |
Held-to-maturity: |  |
12 Months or Greater, Fair Value | $ 22,522 | $ 22,688
12 Months or Greater, Gross Unrealized Losses | $ (2,795) | $ (4,207)
12 Months or Greater, Number of Securities | 5 | 5
Total, Fair Value | $ 22,522 | $ 22,688
Total, Gross Unrealized Losses | $ (2,795) | $ (4,207)
Total, Number of Securities | 5 | 5

X
- Definition Number of investments in debt securities held to maturity, in unrealized loss position, for 12 months or longer, without allowance for credit loss. + References No definition available. + Details
Name: | smbk_DebtSecuritiesHeldToMaturityUnrealizedLossPosition12MonthsOrLongerNumberOfPositions
Namespace Prefix: | smbk_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of investments in debt securities held to maturity, in unrealized loss position, for less than 12 months, without allowance for credit loss. + References No definition available. + Details
Name: | smbk_DebtSecuritiesHeldToMaturityUnrealizedLossPositionLessThan12MonthsNumberOfPositions
Namespace Prefix: | smbk_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerFairValue
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Held-to-Maturity, Debt Securities, Continuous Unrealized Loss Position [Abstract] + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesContinuousUnrealizedLossPositionAbstract
Namespace Prefix: | smbk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsFairValue
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
Namespace Prefix: | smbk_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesUnrealizedLossPositionAccumulatedLoss
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References No definition available. + Details
Name: | smbk_HeldToMaturityDebtSecuritiesUnrealizedLossPositionFairValue
Namespace Prefix: | smbk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |