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Investments (Net Realized and Unrealized Investment Gains and (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 14,552	$ 2,079	$ 16,749	$ 5,755
Gross losses on sales	(19,345)	(1,811)	(32,905)	(6,282)
Net realized (losses) gains on disposals	(4,793)	268	(16,156)	(527)
Net unrealized (losses) gains on equity securities	(21,860)	7,661	(24,014)	18,941
Losses on securities for which we have the intent to sell	(702)	(91)	(5,499)	(453)
Net realized and unrealized investment (losses) gains	(42,880)	10,057	(83,232)	15,176
Change in net realized and unrealized investment gains	(52,900)		(98,400)
Available-for-sale Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit on fixed income securities	(15,519)	2,272	(37,571)	(2,725)
Held-to-maturity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss (expense) benefit on fixed income securities	$ (6)	$ (53)	$ 8	$ (60)

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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