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Investment Information - Other investments and other investable assets (Details) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments accounted for using the fair value option		$ 1,973,550	$ 3,824,796
Other investable assets	[1]	0	500,000
Total other investments		1,973,550	4,324,796
Fixed maturities
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments accounted for using the fair value option		416,698	843,354
Other investments
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments accounted for using the fair value option		1,432,553	2,331,885
Short-term investments
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments accounted for using the fair value option		97,806	557,008
Equity securities
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments accounted for using the fair value option		$ 26,493	$ 92,549
[1] Participation interests in a receivable of a reverse repurchase agreement.

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Certain fixed maturity securities, equity securities and other investments held at fair value under the fair value option afforded by accounting guidance regarding the fair value option for financial assets and liabilities.

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Amount of investments classified as other.

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