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v3.25.0.1

Borrowings and Financing Activities - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | May 31, 2024 | Apr. 30, 2024 | Jan. 31, 2024
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Repayments in cash |  |  | $ 977,079,000 | $ 0 | $ 0 |  |  |
Loss on extinguishment of debt |  |  | 4,275,000 | 0 | $ 0 |  |  |
Collateral |  |  | 6,345,236,000 | 6,085,654,000 |  |  |  |
Residential mortgage loans held for sale | Asset Pledged as Collateral |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Collateral |  |  | 515,000,000 | 31,000,000 |  |  |  |
Total fixed-maturities available for sale | Fixed maturities AFS and trading securities |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
FHLB, collateral pledged |  |  | 49,000,000 | 101,000,000 |  |  |  |
Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Outstanding borrowings |  |  | $ 1,065,337,000 | 1,417,781,000 |  |  |  |
FHLB Advances |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
FHLB maturity period |  |  | 90 days |  |  |  |  |
FHLB Advances | Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
FHLB, ratio of market value of collateral to advances |  |  | 1.03 |  |  |  |  |
FHLB Advances | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
FHLB, ratio of market value of collateral to advances |  |  | 1.14 |  |  |  |  |
Mortgage Loan Financing Facilities | JP Morgan Master Repurchase Agreement |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  |  | $ 300,000,000
Mortgage Loan Financing Facilities | Goldman Sachs Master Repurchase Agreement |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | $ 200,000,000 |  |
Mortgage Loan Financing Facilities | BMO Master Repurchase Agreement |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 400,000,000 |
Revolving Credit Facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Line of credit facility, higher borrowing capacity option |  |  | $ 400,000,000 |  |  |  |  |
Fair value of amount outstanding |  |  | 0 |  |  |  |  |
Revolving Credit Facility | Unsecured Revolving Credit Facility, Expiration Date 2026 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Current borrowing capacity |  |  | $ 275,000,000 |  |  |  |  |
Debt instrument maturity month and year |  |  | 2026-12 |  |  |  |  |
Senior Notes Due 2027 And 2029 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Redemption price, percentage of principal amount |  |  | 100.00% |  |  |  |  |
Stock retention percentage required in order to make capital stock transactions |  |  | 80.00% |  |  |  |  |
Senior Notes due 2029 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 0.30% |  |  |  |  |
Aggregate principal amount |  | $ 625,000,000 |  |  |  |  |  |
Net proceeds received |  | $ 617,000,000 |  |  |  |  |  |
Interest rate on senior notes |  |  | 6.20% |  |  |  |  |
Outstanding borrowings |  |  | $ 617,876,000 | 0 |  |  |  |
Debt instrument maturity date |  |  | May 15, 2029 |  |  |  |  |
Senior Notes due 2025 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Redemption price, percentage of principal amount |  | 100.40% |  |  |  |  |  |
Interest rate on senior notes |  |  | 6.625% |  |  |  |  |
Aggregate principal redemption amount |  | $ 525,000,000 |  |  |  |  |  |
Repayments in cash |  | 527,000,000 |  |  |  |  |  |
Loss on extinguishment of debt |  | $ 4,000,000 |  |  |  |  |  |
Outstanding borrowings |  |  | $ 0 | 522,343,000 |  |  |  |
Senior Notes due 2024 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate on senior notes |  |  | 4.50% |  |  |  |  |
Aggregate principal redemption amount | $ 450,000,000 |  |  |  |  |  |  |
Repayments in cash | $ 460,000,000 |  |  |  |  |  |  |
Outstanding borrowings |  |  | $ 0 | 449,037,000 |  |  |  |
Senior Notes due 2027 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 0.50% |  |  |  |  |
Interest rate on senior notes |  |  | 4.875% |  |  |  |  |
Outstanding borrowings |  |  | $ 447,461,000 | $ 446,401,000 |  |  |  |
Debt instrument maturity date |  |  | Mar. 15, 2027 |  |  |  |  |

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