MARKETABLE SECURITIES (Composition of Marketable Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term	$ 276,241	$ 249,895
Gross Unrealized Gains, Short-term		593
Gross Unrealized Losses, Short-term	(5,178)	(110)
Fair Value, Short-term	271,063	250,378
Amortized Cost, Long-term	524,128	564,355
Gross Unrealized Gains, Long-term		456
Gross Unrealized Losses, Long-term	(20,163)	(2,336)
Fair Value, Long-term	503,965	562,475
Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term	65,662	66,379
Gross Unrealized Gains, Short-term		99
Gross Unrealized Losses, Short-term	(1,457)	(11)
Fair Value, Short-term	64,205	66,467
Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Long-term	67,771	91,185
Gross Unrealized Gains, Long-term		4
Gross Unrealized Losses, Long-term	(2,497)	(409)
Fair Value, Long-term	65,274	90,780
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term	191,993	107,102
Gross Unrealized Gains, Short-term		434
Gross Unrealized Losses, Short-term	(3,646)	(65)
Fair Value, Short-term	188,347	107,471
Amortized Cost, Long-term	280,053	324,492
Gross Unrealized Gains, Long-term		351
Gross Unrealized Losses, Long-term	(12,779)	(1,318)
Fair Value, Long-term	267,274	323,525
Commercial Paper [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term	8,644	38,252
Gross Unrealized Gains, Short-term		2
Gross Unrealized Losses, Short-term	(12)	(1)
Fair Value, Short-term	8,632	38,253
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term		12,931
Gross Unrealized Gains, Short-term		58
Fair Value, Short-term		12,989
Amortized Cost, Long-term	116,909	128,139
Gross Unrealized Gains, Long-term		101
Gross Unrealized Losses, Long-term	(3,340)	(578)
Fair Value, Long-term	113,569	127,662
U.S. Government And Agency Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Short-term	9,942	25,231
Gross Unrealized Losses, Short-term	(63)	(33)
Fair Value, Short-term	9,879	25,198
Amortized Cost, Long-term	59,395	20,539
Gross Unrealized Losses, Long-term	(1,547)	(31)
Fair Value, Long-term	$ 57,848	$ 20,508