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Significant Accounting Policies and Basis of Presentation (Details) $ / shares in Units, $ in Thousands | Dec. 31, 2023 USD ($) renewalOption $ / shares | Dec. 31, 2022 $ / shares | Jan. 03, 2022
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Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Lessee, operating lease, options to renew | renewalOption | 1 |  |
Allowance for credit loss, individually evaluated loans, threshold | $ | $ 500 |  |
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other assets | Other assets |
Class A |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Common stock, par value (in dollars per share) | $ 1 | $ 1 |
Class B |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Common stock, par value (in dollars per share) | $ 1 | $ 1 |
CIT Group Inc. | Class A |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Common stock, terms of conversion, conversion ratio |  |  | 0.062
Rail Equipment | Minimum |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Useful Life (years) | 40 years |  |
Rail Equipment | Maximum |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Useful Life (years) | 50 years |  |
Other Equipment | Minimum |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Useful Life (years) | 3 years |  |
Other Equipment | Maximum |  |  |
Significant Accounting Policies and Basis of Presentation [Line Items] |  |  |
Useful Life (years) | 10 years |  |

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