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SIGNIFICANT ACCOUNTING POLICIES AND BASIS OF PRESENTATION (Details) | Dec. 31, 2024 USD ($) renewalOption $ / shares | Dec. 31, 2023 $ / shares
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Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Allowance for credit loss, individually evaluated loans, threshold | $ 500,000 |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets
Lessee, operating lease, options to renew | renewalOption | 1 |
Class A |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Common stock, par value (in dollars per share) | $ / shares | $ 1 | $ 1
Class B |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Common stock, par value (in dollars per share) | $ / shares | $ 1 | $ 1
Minimum | Rail Equipment |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Useful Life (years) | 40 years |
Minimum | Other Equipment |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Useful Life (years) | 3 years |
Maximum | Rail Equipment |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Useful Life (years) | 50 years |
Maximum | Other Equipment |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Useful Life (years) | 10 years |
Investor dependent - early stage |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Allowance for credit loss, classification threshold | $ 5,000,000 |
Investor dependent - mid stage | Minimum |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Allowance for credit loss, classification threshold | 5,000,000 |
Investor dependent - mid stage | Maximum |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Allowance for credit loss, classification threshold | 15,000,000 |
Investor dependent - later stage | Minimum |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |
Allowance for credit loss, classification threshold | $ 15,000,000 |

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