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Credit and Other Debt Agreements - Note Purchase Agreements - Additional Information (Detail) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Feb. 28, 2023 | Jun. 30, 2022 | Dec. 31, 2023 | Dec. 31, 2022
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate |  |  |  | 6.75% | 6.75%
Semi-annual payments of interest |  |  |  | $ 8,032.0 | $ 6,499.9
Series G note [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate |  |  | 3.69% |  |
Debt instrument, maturity date |  |  | Jun. 14, 2023 |  |
Operating cash to fund |  |  | $ 200.0 |  |
Series N note [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate | 4.13% |  |  |  |
Debt instrument, maturity date | Jun. 24, 2023 |  |  |  |
Operating cash to fund | $ 200.0 |  |  |  |
Series CC note [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, maturity date | Jun. 13, 2024 |  |  |  |
Quarterly payments of interest, description | 90 day LIBOR |  |  |  |
Quarterly payments of interest rate | 1.40% |  |  |  |
Prepayment of debt | $ 50.0 |  |  |  |
Series E note [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, interest rate |  | 5.49% |  |  |
Debt instrument, maturity date |  | Feb. 10, 2023 |  |  |
Operating cash to fund |  | $ 50.0 |  |  |
Note Purchase Agreements [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Semi-annual payments of interest |  |  |  | $ 3,948.0 | $ 4,248.0
Amount payable to redeem the notes, percent of the principal amount |  |  |  | 100.00% |
Discount rate used to compute the remaining scheduled payments of principal and interest |  |  |  | U.S. Treasury yield plus 0.5 |

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