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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, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 1,156	$ 14,552	$ 4,940	$ 16,749
Gross losses on sales	(11,952)	(19,345)	(24,882)	(32,905)
Net realized gains (losses) on disposals	(10,796)	(4,793)	(19,942)	(16,156)
Net unrealized gains (losses) on equity securities	4,925	(21,860)	8,173	(24,014)
Losses on securities for which we have the intent to sell	(341)	(702)	(645)	(5,499)
Net realized and unrealized investment gains (losses)	(5,426)	(42,880)	(2,082)	(83,232)
Available-for-sale Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	864	(15,519)	10,393	(37,571)
Held-to-maturity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	0	(6)	0	8
Commercial Mortgage Loans [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	$ (78)	$ 0	$ (61)	$ 0

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Losses on investment securities for which we have the intent to sell

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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-Section 50
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