INVESTMENTS - Summary of Cost and Fair Value of Equity Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Cost	$ 494,356	$ 528,864
Gross unrealized gains	68,694	135,230
Gross unrealized losses	(77,797)	(8,419)
Fair value	485,253	655,675
Common stocks
Debt and Equity Securities, FV-NI [Line Items]
Cost	7,279	1,264
Gross unrealized gains	636	585
Gross unrealized losses	(442)	(485)
Fair value	7,473	1,364
Preferred stocks
Debt and Equity Securities, FV-NI [Line Items]
Cost	115	115
Gross unrealized gains	0	64
Gross unrealized losses	(43)	0
Fair value	72	179
Exchange-traded funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	207,505	203,455
Gross unrealized gains	68,058	134,037
Gross unrealized losses	(5,757)	(677)
Fair value	269,806	336,815
Bond mutual funds
Debt and Equity Securities, FV-NI [Line Items]
Cost	279,457	324,030
Gross unrealized gains	0	544
Gross unrealized losses	(71,555)	(7,257)
Fair value	$ 207,902	$ 317,317

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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Amount of unrealized gain 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 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714

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Amount of unrealized 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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