Investments - Schedule of Pretax Net Realized Investment Gains (Losses) and Net Changes in Unrealized Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment1 [Line Items]
Net realized gains (losses)	$ 64,222	$ 17,885	$ 17,520
Net unrealized gains (losses) on equity securities	65,258	32,101	78,090
Net changes in unrealized gains (losses) on investments:	(74,541)	71,163	84,867
Net realized gains (losses) and changes in unrealized gains (losses) on investments	54,939	121,149	180,477
Debt Securities \| Available for sale securities
Investment1 [Line Items]
Net realized gains (losses)	1,859	3,872	3,184
Net changes in unrealized gains (losses) on investments:	(71,538)	67,350	83,758
Equity Securities
Investment1 [Line Items]
Net realized gains (losses)	62,512	15,796	14,445
Net unrealized gains (losses) on equity securities	58,459	32,317	78,389
Other
Investment1 [Line Items]
Net realized gains (losses)	(149)	(1,783)	(109)
Net unrealized gains (losses) on equity securities	6,799	(216)	(299)
Net changes in unrealized gains (losses) on investments:	44	369
Equity Method Investments
Investment1 [Line Items]
Net changes in unrealized gains (losses) on investments:	$ (3,047)	$ 3,444	$ 1,109

INVESTMENTS

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Amount of net total realized gain (loss) included in earnings for the period as a result of the sale of marketable securities and the sale or disposal of other assets.

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The aggregate difference between the fair value and the carrying value, or in the comparative fair values, of marketable securities recognized in other comprehensive earnings and/or any unrealized gains or losses on investments that are separately or otherwise not categorized as trading, available-for-sale or held-to-maturity.

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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-Topic 321
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-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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Amount of realized and unrealized gain (loss) on investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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