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Investments Realized and Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 28,419	$ 15,284	$ 18,893
Gross losses on sales	(60,055)	(8,140)	(9,745)
Net realized investment gains (losses) on disposals	(31,636)	7,144	9,148
Net unrealized (losses) gains on equity securities	(32,127)	17,881	7,939
Losses on securities for which we have the intent to sell	(11,823)	(519)	(16,266)
Net realized and unrealized investment (losses) gains	(114,808)	17,599	(4,217)
Available-for-sale Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit	(39,169)	(6,858)	(5,042)
Held-to-maturity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit	63	(49)	4
Commercial Mortgage Loans [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit	$ (116)	$ 0	$ 0

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The credit loss expensed during the period on investment portfolio.

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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