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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale, Amortized Cost | $ 2,005 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 1 | $ 0
Premium Receivable, Allowance for Credit Loss | $ 8 | $ 9
Preferred stock, par value | $ 0.01 |
Preferred stock, shares authorized | 20,000,000 |
Preferred Stock, Shares Issued | 0 |
Common stock, par value | $ 0.01 |
Common stock, shares authorized | 130,000,000 |
Common stock, shares issued | 46,658,990 | 46,477,068
Common stock, shares outstanding | 46,545,232 |
Treasury stock, shares | 113,758 | 172,929
Equity investments in pooled funds [Member] |  |
Other Investment Not Readily Marketable, Fair Value | $ 652 | $ 683
Variable Interest Entity, Primary Beneficiary [Member] |  |
Long-term debt | $ 3,701 | $ 4,056

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