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Fair Value Measurement - Quantitative Information - Assets & Liabilities (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 USD ($) Year | Mar. 31, 2026 USD ($) risk Year
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | $ 6,369 | $ 6,875
Fixed-maturity securities, trading | 124 | 127
Funds withheld, at fair value | 0 | 296
Total assets carried at fair value | 7,912 | 8,416
FG VIEs’ assets, measurement input | 167 |
Other assets | 174 | 180
FG VIEs' liabilities | (218) | (178)
Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | 172 | 167
FG VIEs' liabilities | (197) | (152)
Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 1,769 | 1,744
Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 2,952 | 3,350
RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 615 | 624
CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 456 | 374
Others |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 209 | 241
Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 833 | 741
Fixed-maturity securities, trading | 4 | 8
Funds withheld, at fair value |  | 296
Total assets carried at fair value | 1,185 | 1,227
FG VIEs’ assets, measurement input | 167 |
Other assets | 28 | 33
FG VIEs' liabilities | (218) | (173)
Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | 150 | 146
FG VIEs' liabilities | (197) | (152)
Level 3 | Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 10 | 10
Level 3 | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 168 | 162
Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 144 | 140
Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, trading | 4 | 8
Funds withheld, at fair value |  | 296
Other assets | 22 | 28
Credit derivative liabilities, net | (15) | (16)
Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | 150 | 146
FG VIEs' liabilities | (197) | (152)
Discounted Cash Flow | Level 3 | Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 10 | 10
Discounted Cash Flow | Level 3 | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 168 | 162
Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 144 | 140
Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 456 | 374
Discounted Cash Flow | Level 3 | Others |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale | 55 | $ 55
Income Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets, measurement input | $ 167 |
Measurement Input, Yield | Discounted Cash Flow | Level 3 | Others |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.091 | 0.090
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, trading, measurement input | 0.001 | 0.037
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.060 | 0.063
FG VIEs’ liabilities | 0.050 | 0.051
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 | Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.052 | 0.054
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.050 | 0.057
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.070 | 0.074
Measurement Input, Yield | Minimum | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.110 | 0.099
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, trading, measurement input | 0.088 | 0.200
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.098 | 0.103
FG VIEs’ liabilities | 0.098 | 0.103
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 | Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.150 | 0.150
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.080 | 0.087
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.099 | 0.103
Measurement Input, Yield | Maximum | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.265 | 0.360
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, trading, measurement input | 0.044 | 0.150
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.087 | 0.074
FG VIEs’ liabilities | 0.065 | 0.068
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 | Obligations of state and political subdivisions |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.066 | 0.074
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 | Corporate securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.052 | 0.059
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.083 | 0.087
Measurement Input, Yield | Weighted Average | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.190 | 0.236
Conditional prepayment rate (CPR) | Minimum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.002 | 0.001
FG VIEs’ liabilities | 0.002 | 0.001
Conditional prepayment rate (CPR) | Minimum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.000 | 0.000
Conditional prepayment rate (CPR) | Maximum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.275 | 0.262
FG VIEs’ liabilities | 0.275 | 0.262
Conditional prepayment rate (CPR) | Maximum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.213 | 0.222
Conditional prepayment rate (CPR) | Weighted Average | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.053 | 0.057
FG VIEs’ liabilities | 0.053 | 0.057
Conditional prepayment rate (CPR) | Weighted Average | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.041 | 0.042
CDR | Minimum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.012 | 0.012
FG VIEs’ liabilities | 0.012 | 0.012
CDR | Minimum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.012 | 0.013
CDR | Maximum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.410 | 0.410
FG VIEs’ liabilities | 0.410 | 0.410
CDR | Maximum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.186 | 0.185
CDR | Weighted Average | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.105 | 0.106
FG VIEs’ liabilities | 0.105 | 0.106
CDR | Weighted Average | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.056 | 0.055
Loss severity | Minimum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.450 | 0.450
FG VIEs’ liabilities | 0.450 | 0.450
Loss severity | Minimum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.500 | 0.500
Loss severity | Maximum | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 1.000 | 1.000
FG VIEs’ liabilities | 1.000 | 1.000
Loss severity | Maximum | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 1.250 | 1.250
Loss severity | Weighted Average | Discounted Cash Flow | Level 3 | Variable Interest Entity, Primary Beneficiary |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
FG VIEs’ assets | 0.836 | 0.837
FG VIEs’ liabilities | 0.836 | 0.837
Loss severity | Weighted Average | Discounted Cash Flow | Level 3 | RMBS |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.792 | 0.792
Discount margin | Income Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets of CIVs - equity securities, measurement input | 0.233 |
Discount margin | Minimum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Funds withheld, measurement input | risk |  | 0.028
Credit derivative liabilities, net, measurement input | 0.033 | 0.035
Discount margin | Minimum | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.010 | 0.009
Discount margin | Maximum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Funds withheld, measurement input | risk |  | 0.069
Credit derivative liabilities, net, measurement input | 0.045 | 0.044
Discount margin | Maximum | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.029 | 0.029
Discount margin | Weighted Average | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Funds withheld, measurement input | risk |  | 0.045
Credit derivative liabilities, net, measurement input | 0.043 | 0.043
Discount margin | Weighted Average | Discounted Cash Flow | Level 3 | CLOs |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fixed-maturity securities, available for sale, measurement input | 0.017 | 0.017
Market multiple-price to earnings | Market Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets of CIVs - equity securities, measurement input | 5.75 |
Terminal growth rate | Market Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets of CIVs - equity securities, measurement input | 0.040 |
Implied Yield | Minimum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value inputs term | 0.064 | 0.066
Implied Yield | Maximum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value inputs term | 0.069 | 0.071
Implied Yield | Weighted Average | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value inputs term | 0.066 | 0.069
Term (years) | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair value inputs term | Year | 10 | 10
Hedge cost (in basis points) (bps) | Minimum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.00115 | 0.00132
Hedge cost (in basis points) (bps) | Maximum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.00274 | 0.00312
Hedge cost (in basis points) (bps) | Weighted Average | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.00151 | 0.00176
Bank profit (in bps) | Minimum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.00660 | 0.00677
Bank profit (in bps) | Maximum | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.02619 | 0.02730
Bank profit (in bps) | Weighted Average | Discounted Cash Flow | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Credit derivative liabilities, net, measurement input | 0.01247 | 0.01403
Market multiple-price to book | Market Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets of CIVs - equity securities, measurement input | 1.00 |
Exit multiple-price to earnings | Market Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets of CIVs - equity securities, measurement input | 5.50 |
Consolidated Investment Vehicles | Terminal growth rate | Income Approach | Level 3 | Exit multiple-price to book |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Yield (as a percent) | 100.00% |
Other invested assets | Income Approach | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Total assets carried at fair value | $ 3 | $ 3

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- Definition Fair value portion of asset recognized for present right to economic benefit. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 100 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-100 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 + Details
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