INVESTMENTS AND FAIR VALUE MEASUREMENTS - AMORTIZED COST (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	$ 156,659	$ 118,761
Unrealized Gains	4,108	3,006
Unrealized Losses	(8,800)	(9,109)
Fair Value	151,967	112,658
Marketable Equity Securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	94,820	79,625
Unrealized Gains	3,214	2,776
Unrealized Losses	(8,658)	(8,979)
Fair Value	89,376	73,422
Marketable Equity Securities | Mutual Fund
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	27,020	26,352
Unrealized Gains	0	0
Unrealized Losses	(2,955)	(3,143)
Fair Value	24,065	23,209
Marketable Equity Securities | Equity Securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	67,800	53,273
Unrealized Gains	3,214	2,776
Unrealized Losses	(5,703)	(5,836)
Fair Value	65,311	50,213
Marketable Debt Securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	61,839	39,136
Unrealized Gains	894	230
Unrealized Losses	(142)	(130)
Fair Value	62,591	39,236
Marketable Debt Securities | Corporate Bond Securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	13,305	13,496
Unrealized Gains	87	48
Unrealized Losses	(99)	(106)
Fair Value	13,293	13,438
Marketable Debt Securities | U.S. treasury securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	48,534	25,640
Unrealized Gains	807	182
Unrealized Losses	(43)	(24)
Fair Value	$ 49,298	$ 25,798