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Investments Realized and Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 15,284	$ 18,893	$ 31,910
Gross losses on sales	(8,140)	(9,745)	(5,195)
Net realized investment gains (losses) on disposals	7,144	9,148	26,715
Net unrealized losses on equity securities	17,881	7,939	(8,649)
Losses on securities for which we have the intent to sell	(519)	(16,266)
OTTI Losses Gross			(3,644)
Net realized and unrealized investment gains (losses)	17,599	(4,217)	14,422
Sale of equity securities	99,235	1,320	$ 137,294
Losses on securities for which we have the intent to sell	(519)	(16,266)
Available-for-sale Securities [Member]
Credit loss expense on investment portfolio	(6,858)	(5,042)
Held-to-maturity Securities [Member]
Credit loss expense on investment portfolio	$ (49)	$ 4

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