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Investments (Net Realized and Unrealized Investment Gains and (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 7,094	$ 7,151	$ 23,843	$ 12,906
Gross losses on sales	(19,668)	(2,505)	(52,573)	(8,787)
Net realized (losses) gains on disposals	(12,574)	4,646	(28,730)	4,119
Net unrealized (losses) gains on equity securities	(7,777)	(3,111)	(31,791)	15,830
Losses on securities for which we have the intent to sell	(913)	(30)	(6,412)	(483)
Net realized and unrealized investment (losses) gains	(25,681)	177	(108,913)	15,353
Change in net realized and unrealized investment gains	(25,900)		(124,300)
Available-for-sale Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit on fixed income securities	(4,471)	(1,334)	(42,042)	(4,059)
Held-to-maturity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit on fixed income securities	$ 54	$ 6	$ 62	$ (54)

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Increase (decrease) in gain (loss) on investments

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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