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Investments (Tables) | 12 Months Ended
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Dec. 31, 2022
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Amortized Cost And Fair Value Of Available-For-Sale And Held-To-Maturity Investment Portfolios | The following tables present the amortized cost, allowance for credit losses, corresponding gross unrealized gains and losses and fair value for AFS investments in the Company’s consolidated investment portfolio as of December 31, 2022 and 2021:
|  | December 31, 2022 |
In millions |  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
AFS Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agency |  | $ | 541 |  |  | $ | — |  |  | $ | 5 |  |  | $ | (38) |  |  | $ | 508 |
State and municipal bonds |  |  | 173 |  |  |  | — |  |  |  | 2 |  |  |  | (11) |  |  |  | 164 |
Foreign governments |  |  | 23 |  |  |  | — |  |  |  | — |  |  |  | (3) |  |  |  | 20 |
Corporate obligations |  |  | 862 |  |  |  | — |  |  |  | 1 |  |  |  | (148) |  |  |  | 715 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential mortgage-backed agency |  |  | 217 |  |  |  | — |  |  |  | — |  |  |  | (22) |  |  |  | 195 |
Residential mortgage-backed non-agency |  |  | 96 |  |  |  | — |  |  |  | 3 |  |  |  | (11) |  |  |  | 88 |
Commercial mortgage-backed |  |  | 24 |  |  |  | — |  |  |  | — |  |  |  | (1) |  |  |  | 23 |
Asset-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized debt obligations |  |  | 117 |  |  |  | — |  |  |  | — |  |  |  | (5) |  |  |  | 112 |
Other asset-backed |  |  | 110 |  |  |  | — |  |  |  | — |  |  |  | (4) |  |  |  | 106 |
Total AFS investments |  | $ | 2,163 |  |  | $ | — |  |  | $ | 11 |  |  | $ | (243) |  |  | $ | 1,931 |
|  | December 31, 2021 |
In millions |  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
AFS Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agency |  | $ | 782 |  |  | $ | — |  |  | $ | 54 |  |  | $ | (2) |  |  | $ | 834 |
State and municipal bonds |  |  | 140 |  |  |  | — |  |  |  | 27 |  |  |  | — |  |  |  | 167 |
Foreign governments |  |  | 13 |  |  |  | — |  |  |  | 1 |  |  |  | — |  |  |  | 14 |
Corporate obligations |  |  | 905 |  |  |  | — |  |  |  | 53 |  |  |  | (5) |  |  |  | 953 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential mortgage-backed agency |  |  | 190 |  |  |  | — |  |  |  | 3 |  |  |  | (1) |  |  |  | 192 |
Residential mortgage-backed non-agency |  |  | 80 |  |  |  | — |  |  |  | 12 |  |  |  | — |  |  |  | 92 |
Commercial mortgage-backed |  |  | 10 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 10 |
Asset-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized debt obligations |  |  | 101 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 101 |
Other asset-backed |  |  | 95 |  |  |  | — |  |  |  | — |  |  |  | (1) |  |  |  | 94 |
Total AFS investments |  | $ | 2,316 |  |  | $ | — |  |  | $ | 150 |  |  | $ | (9) |  |  | $ | 2,457 |
Distribution By Contractual Maturity Of Available-For-Sale and Held-To-Maturity Investments | The following table presents the distribution by contractual maturity of AFS fixed-maturity securities at amortized cost, net of allowance for credit losses, and fair value as of December 31, 2022. Contractual maturity may differ from expected maturity as borrowers may have the right to call or prepay obligations.
|  | AFS Securities |
In millions |  | Net Amortized Cost |  |  | Fair Value |
Due in one year or less |  | $ | 199 |  |  | $ | 197 |
Due after one year through five years |  |  | 280 |  |  |  | 270 |
Due after five years through ten years |  |  | 332 |  |  |  | 288 |
Due after ten years |  |  | 788 |  |  |  | 652 |
Mortgage-backed and asset-backed |  |  | 564 |  |  |  | 524 |
Total fixed-maturity investments |  | $ | 2,163 |  |  | $ | 1,931 |
Gross Unrealized Losses Related To Available-For-Sale And Held-To-Maturity Investments | The following tables present the non-credit related gross unrealized losses related to AFS investments as of December 31, 2022 and 2021:
|  | December 31, 2022 |
|  | Less than 12 Months |  |  | 12 Months or Longer |  |  | Total |
In millions |  | Fair Value |  |  | Unrealized Losses |  |  | Fair Value |  |  | Unrealized Losses |  |  | Fair Value |  |  | Unrealized Losses |
AFS Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agency |  | $ | 266 |  |  | $ | (34) |  |  | $ | 29 |  |  | $ | (4) |  |  | $ | 295 |  |  | $ | (38) |
State and municipal bonds |  |  | 92 |  |  |  | (10) |  |  |  | 1 |  |  |  | (1) |  |  |  | 93 |  |  |  | (11) |
Foreign governments |  |  | 9 |  |  |  | (3) |  |  |  | — |  |  |  | — |  |  |  | 9 |  |  |  | (3) |
Corporate obligations |  |  | 508 |  |  |  | (106) |  |  |  | 141 |  |  |  | (42) |  |  |  | 649 |  |  |  | (148) |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential mortgage-backed agency |  |  | 112 |  |  |  | (9) |  |  |  | 65 |  |  |  | (13) |  |  |  | 177 |  |  |  | (22) |
Residential mortgage-backed non-agency |  |  | 65 |  |  |  | (10) |  |  |  | 2 |  |  |  | (1) |  |  |  | 67 |  |  |  | (11) |
Commercial mortgage-backed |  |  | 18 |  |  |  | (1) |  |  |  | 1 |  |  |  | — |  |  |  | 19 |  |  |  | (1) |
Asset-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized debt obligations |  |  | 51 |  |  |  | (1) |  |  |  | 60 |  |  |  | (4) |  |  |  | 111 |  |  |  | (5) |
Other asset-backed |  |  | 44 |  |  |  | (3) |  |  |  | 24 |  |  |  | (1) |  |  |  | 68 |  |  |  | (4) |
Total AFS investments |  | $ | 1,165 |  |  | $ | (177) |  |  | $ | 323 |  |  | $ | (66) |  |  | $ | 1,488 |  |  | $ | (243) |
|  | December 31, 2021 |
|  | Less than 12 Months |  |  | 12 Months or Longer |  |  | Total |
In millions |  | Fair Value |  |  | Unrealized Losses |  |  | Fair Value |  |  | Unrealized Losses |  |  | Fair Value |  |  | Unrealized Losses |
AFS Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agency |  | $ | 161 |  |  | $ | (1) |  |  | $ | 16 |  |  | $ | (1) |  |  | $ | 177 |  |  | $ | (2) |
State and municipal bonds |  |  | 11 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 11 |  |  |  | — |
Foreign governments |  |  | 3 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 3 |  |  |  | — |
Corporate obligations |  |  | 270 |  |  |  | (5) |  |  |  | 8 |  |  |  | — |  |  |  | 278 |  |  |  | (5) |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential mortgage-backed agency |  |  | 94 |  |  |  | (1) |  |  |  | 1 |  |  |  | — |  |  |  | 95 |  |  |  | (1) |
Residential mortgage-backed non-agency |  |  | 3 |  |  |  | — |  |  |  | 1 |  |  |  | — |  |  |  | 4 |  |  |  | — |
Commercial mortgage-backed |  |  | 2 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 2 |  |  |  | — |
Asset-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collateralized debt obligations |  |  | 60 |  |  |  | — |  |  |  | 29 |  |  |  | — |  |  |  | 89 |  |  |  | — |
Other asset-backed |  |  | 72 |  |  |  | (1) |  |  |  | — |  |  |  | — |  |  |  | 72 |  |  |  | (1) |
Total AFS investments |  | $ | 676 |  |  | $ | (8) |  |  | $ | 55 |  |  | $ | (1) |  |  | $ | 731 |  |  | $ | (9) |
Distribution Of Securities By Percentage Of Fair Value Below Book Value By More Than 5% | The following table presents the distribution of securities in an unrealized loss position for a continuous twelve-month period or longer where fair value was below book value by more than 5% as of December 31, 2022:
|  | AFS Securities |
Percentage of Fair Value Below Book Value |  | Number of Securities |  |  | Book Value (in millions) |  |  | Fair Value (in millions) |
> 5% to 15% |  |  | 72 |  |  | $ | 129 |  |  | $ | 117 |
> 15% to 25% |  |  | 63 |  |  |  | 117 |  |  |  | 93 |
> 25% to 50% |  |  | 53 |  |  |  | 84 |  |  |  | 56 |
> 50% |  |  | 2 |  |  |  | — |  |  |  | — |
Total |  |  | 190 |  |  | $ | 330 |  |  | $ | 266 |
Summary of Allowance for Credit Losses on AFS Investments | The following table presents the rollforward of allowance for credit losses on AFS investments for the year ended December 31, 2022. The additions to the allowance for credit losses for the year ended December 31, 2022 were related to concerns on an issuer’s credit deterioration as a result of the Ukraine and Russia conflict. Such allowance for credit losses was reversed in the same year due to the Company’s intent to sell these securities. The Company did not establish an allowance for credit losses for AFS securities during 2021.
|  | Years Ended December 31, 2022 |
In millions |  | Balance as of December 31, 2021 |  |  | Additions not previously recorded |  |  | Additions arising from PCD Assets |  |  | Reductions from Securities Sold |  |  | Reductions- Intent to sell or MLTN |  |  | Change in Allowance Previously Recorded |  |  | Write Offs |  |  | Recoveries |  |  | Balance as of December 31, 2022 |
AFS Investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate obligations |  | $ | — |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | (3) |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Total Allowance on AFS investments |  | $ | — |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | (3) |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Securities Held In Unrealized Loss Position And Insured By Financial Guarantor and The Related Insurance Loss Reserve On Company Insured Investments | The following table provides information about securities held by the Company as of December 31, 2022 that were in an unrealized loss position and insured by a financial guarantor, along with the amount of insurance loss reserves corresponding to the par amount owned by the Company. The Company did not hold any securities in an unrealized loss position that were insured by a third-party financial guarantor as of December 31, 2022.
In millions |  | Fair Value |  |  | Unrealized Loss |  |  | Insurance Loss Reserve (1) |
Mortgage-backed |  | $ | 58 |  |  | $ | (9) |  |  | $ | 71 |
Corporate obligations |  |  | 71 |  |  |  | (35) |  |  |  | — |
Total |  | $ | 129 |  |  | $ | (44) |  |  | $ | 71 |
(1)—Insurance loss reserve estimates are based on the proportion of par value owned to the total amount of par value insured and are discounted using a discount rate equal to the risk-free rate applicable to the currency and weighted average remaining life of the insurance contract and may differ from the fair value.
Gross Realized Gains and Losses From Sales Of Available-For-Sale Securities | The proceeds and the gross realized gains and losses from sales of fixed-maturity securities held as AFS for the years ended December 31, 2022, 2021 and 2020 are as
|  | Years Ended December 31, |
In millions |  | 2022 |  |  | 2021 |  |  | 2020 |
Proceeds from sales |  | $ | 1,100 |  |  | $ | 597 |  |  | $ | 1,095 |
Gross realized gains |  | $ | 5 |  |  | $ | 12 |  |  | $ | 59 |
Gross realized losses |  | $ | (47) |  |  | $ | (9) |  |  | $ | (15) |
Portion Of Unrealized Gains Losses Recognized On Equity Investments |
|  | Years Ended December 31, |
In millions |  | 2022 |  |  | 2021 |  |  | 2020 |
Net gains and (losses) recognized during the period on equity securities |  | $ | (21) |  |  | $ | 6 |  |  | $ | 3 |
Less: |  |  |  |  |  |  |  |  |  |  |  |
Net gains and (losses) recognized during the period on equity securities sold during the period |  |  | (6) |  |  |  | 1 |  |  |  | (1) |
Unrealized gains and (losses) recognized during the period on equity securities still held at the reporting date |  | $ | (15) |  |  | $ | 5 |  |  | $ | 4 |

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