FAIR VALUE MEASUREMENTS (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Level 1 [Member] | Money Market Mutual Funds [Member]
Fair value of assets	$ 93,085	$ 480,673
Level 2 [Member] | Options and forward contracts not designated as hedging instruments [Member] | Derivative Financial Instruments Liabilities [Member]
Fair value of liabilities	(523)	(5,819)
Level 2 [Member] | Derivative Financial Instruments, Assets [Member] | Derivatives designated as cash flow hedging instruments [Member]
Fair value of assets	354
Level 2 [Member] | Derivative Financial Instruments, Assets [Member] | Options and forward contracts not designated as hedging instruments [Member]
Fair value of assets	2,346	3,786
Level 2 [Member] | Short-term corporate bonds [Member]
Fair value of assets	139,053	142,276
Level 2 [Member] | Short-term governmental bonds [Member]
Fair value of assets	6,633	1,411
Level 2 [Member] | Long-term corporate bonds [Member]
Fair value of assets	446,821	142,552
Level 2 [Member] | Long-term governmental bonds [Member]
Fair value of assets	$ 10,541	$ 4,882