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Fair Value Measurements - Information about Valuation Inputs for Variable Interest Entity Assets and Liabilities Classified as Level 3 (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |  |  |
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Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2023 | Dec. 31, 2022
Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Estimated Future Premium Payments Minimum Discounted Rate | 5.80% |  | 5.80% |  | 5.30% |  |  |  |
Estimated Future Premium Payments Maximum Discounted Rate | 8.20% |  | 8.20% |  | 7.80% |  |  |  |
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | $ 3,672,000 | $ 3,831,000 | $ 3,672,000 | $ 3,831,000 |  | $ 3,782,000 | $ 3,848,000 | $ 3,972,000 | $ 3,762,000
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (19,000) | (124,000) | 16,000 | 73,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 15,000 | 64,000 | (23,000) | 152,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (106,000) | (81,000) | (170,000) | (155,000) |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | 16,000 | 73,000 |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Investments [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 77,000 | 81,000 | 77,000 | 81,000 |  | 87,000 | 87,000 | 81,000 | 79,000
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 7,000 | 0 | 7,000 | 1,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 9,000 | 0 | 9,000 | 3,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (26,000) | 0 | (27,000) | (1,000) |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | 7,000 | 1,000 |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 18,000 | 25,000 | 18,000 | 25,000 |  |  | 26,000 |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  | (8,000) |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  | 0 |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  | 0 |  |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | (8,000) |  |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Loans Receivable [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  |  |  |  |  |  |  |  | 1,829,000
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  |  | (7,000) |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  |  | 92,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  |  | (141,000) |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  |  | (7,000) |  |  |  |  |
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  |  |  |  |  |  |  |  | 1,828,000
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  |  | 80,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  |  | 57,000 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  |  | (12,000) |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  |  | 80,000 |  |  |  |  |
Loan Origination Commitments [Member] | Fair Value, Inputs, Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 1,567,000 | 1,772,000 | 1,567,000 | 1,772,000 |  |  | 1,663,000 |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  | 49,000 |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  | (14,000) |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  | (132,000) |  |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | 49,000 |  |  |  |  |  |
Loan Origination Commitments [Member] | Fair Value, Inputs, Level 3 [Member] | Loans Receivable [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 1,567,000 | 1,772,000 | 1,567,000 | 1,772,000 |  | 1,604,000 |  | 1,856,000 |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | 29,000 | (66,000) |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 3,000 | 50,000 |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | (68,000) | (69,000) |  |  |  |  |  |  |
Derivative Financial Instruments, Liabilities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability |  |  |  |  |  |  |  |  | $ 26,000
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  |  | 0 |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  |  | 0 |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  |  | 0 |  |  |  |  |
Derivative Financial Instruments, Liabilities [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 18,000 | 25,000 | 18,000 | 25,000 |  | 21,000 |  | 31,000 |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (3,000) | (5,000) |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | 0 | 0 |  |  |  |  |  |  |
Investment Contracts [Member] | Fair Value, Inputs, Level 3 [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 2,010,000 | 1,952,000 | 2,010,000 | 1,952,000 |  |  | $ 2,072,000 |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings |  |  | (32,000) |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss |  |  | (18,000) |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements |  |  | (12,000) |  |  |  |  |  |
Fair Value Asset Or Liability Measured On Recurring Basis Change In Unrealized Gains Losses Still Held |  |  | (32,000) |  |  |  |  |  |
Investment Contracts [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |  |  |  |  |  |  |
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability | 2,010,000 | 1,952,000 | $ 2,010,000 | $ 1,952,000 |  | $ 2,070,000 |  | $ 2,003,000 |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Earnings | (51,000) | (53,000) |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Gain Loss Included In Other Comprehensive Income Loss | 3,000 | 14,000 |  |  |  |  |  |  |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liability Settlements | $ (12,000) | $ (12,000) |  |  |  |  |  |  |

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- Definition Estimated Future Premium Payments Maximum Discounted Rate + References No definition available. + Details
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- Definition Estimated Future Premium Payments Minimum Discounted Rate + References No definition available. + Details
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- Definition The amount of gains or losses included in earnings attributable to unrealized gains or losses on financial instruments measured on a recurring basis using unobservable inputs that are still held at the reporting date. + References No definition available. + Details
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis asset or liability. + References No definition available. + Details
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- Definition Amount of gain or loss included in earnings arising from financial instruments measured on a recurring basis using unobservable inputs. + References No definition available. + Details
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- Definition Amount of gain or loss included in other comprehensive income arising from financial instruments measured on a recurring basis using unobservable inputs. + References No definition available. + Details
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- Definition Amount of settlements related to financial instruments measured on a recurring basis using unobservable inputs. + References No definition available. + Details
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