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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fixed income securities, amortized cost | $ 2,140 |
Short-term investments, amortized cost | 415 | $ 492
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0
Uncollectable premium receivables | 9 | 17
Reinsurance Recoverable, Allowance for Credit Loss | $ 0 | $ 0
Preferred stock, par value | $ 0.01 |
Preferred stock, shares authorized | 20,000,000 | 20,000,000
Preferred Stock, Shares Outstanding | 0 | 0
Common stock, shares authorized | 130,000,000 | 130,000,000
Common stock, shares issued | 46,477,068 | 45,865,081
Common Stock, Shares, Outstanding | 46,304,139 |
Treasury stock, shares | 172,929 | 55,942
Fixed Income Securities [Member] |  |
Fixed income securities, amortized cost | $ 1,605 | $ 2,175
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0
Equity investments in pooled funds [Member] |  |
Other Investment Not Readily Marketable, Fair Value | 683 | 544
Collateral Pledged [Member] |  |
Short-term investments, amortized cost | 105 | 125
Collateral Pledged [Member] | Fixed Income Securities [Member] |  |
Fixed income securities, amortized cost | 15 | 15
Short-term Investments [Member] |  |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0
Short-term Investments [Member] | Collateral Pledged [Member] | Fixed Income Securities [Member] |  |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0
Variable Interest Entity, Primary Beneficiary [Member] |  |
Long-term Debt | 4,056 | 4,324
Parent Company [Member] |  |
Fixed income securities, amortized cost | 130 | 76
Debt Securities, Available-for-sale, Allowance for Credit Loss | 3 | 2
Parent Company [Member] | Short-term Investments [Member] |  |
Fixed income securities, amortized cost | $ 124 | $ 229

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