XML 55 R42.htm IDEA: XBRL DOCUMENT
v3.25.2

Loan and Lease Financings (Details 3) - USD ($) $ in Thousands | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Allowance for loan and lease losses | $ 163,484 | $ 157,470 | $ 155,540 | $ 150,067 | $ 148,024 | $ 147,552
Real estate |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 2,387 |  | 1,055 |  |  |
Real estate | Commercial and agricultural |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
Real estate | Auto and light truck |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
Real estate | Construction equipment |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
Real estate | Commercial real estate |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 2,387 |  | 1,055 |  |  |
Equipment |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 57,048 |  | 18,343 |  |  |
Equipment | Commercial and agricultural |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
Equipment | Auto and light truck |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 43,960 |  | 939 |  |  |
Equipment | Construction equipment |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 13,088 |  | 17,404 |  |  |
Equipment | Commercial real estate |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
General business assets |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 5,572 |  | 4,102 |  |  |
General business assets | Commercial and agricultural |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 5,572 |  | 4,102 |  |  |
General business assets | Auto and light truck |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
General business assets | Construction equipment |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
General business assets | Commercial real estate |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 0 |  | 0 |  |  |
Collateral Pledged |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 65,007 |  | 23,500 |  |  |
Allowance for loan and lease losses | 2,256 |  | 209 |  |  |
Collateral Pledged | Commercial and agricultural |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 5,572 |  | 4,102 |  |  |
Allowance for loan and lease losses | 1,026 |  | 209 |  |  |
Collateral Pledged | Auto and light truck |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 43,960 |  | 939 |  |  |
Allowance for loan and lease losses | 1,228 |  | 0 |  |  |
Collateral Pledged | Construction equipment |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 13,088 |  | 17,404 |  |  |
Allowance for loan and lease losses | 0 |  | 0 |  |  |
Collateral Pledged | Commercial real estate |  |  |  |  |  |
Amortized cost of collateral-dependent loans and leases |  |  |  |  |  |
Loans and leases | 2,387 |  | 1,055 |  |  |
Allowance for loan and lease losses | $ 2 |  | $ 0 |  |  |

X
- Definition Schedule of Financing Receivable By Collateral Type [Line Items] + References No definition available. + Details
Name: | source_ScheduleOfFinancingReceivableByCollateralTypeLineItems
Namespace Prefix: | source_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_RealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

X
- Details
Name: | us-gaap_CollateralAxis=source_OtherCollateralMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |