FINANCIAL INSTRUMENTS - Schedule of Cash, Cash Equivalents, Investments and Restricted Cash and Investments Unrealized Loss Positions (Details) $ in Thousands	Sep. 27, 2020 USD ($)
Fair Value
Unrealized Losses Less than 12 Months	$ 603,485
Unrealized Losses 12 Months or Greater	7,953
Total	611,438
Gross Unrealized Loss
Unrealized Losses Less than 12 Months	(420)
Unrealized Losses 12 Months or Greater	(583)
Total	(1,003)
U.S. Treasury and agencies
Fair Value
Unrealized losses less than 12 months, available for sale	74,231
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	74,231
Gross Unrealized Loss
Unrealized losses less than 12 months, available for sale	(1)
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	(1)
Mutual funds
Fair Value
Unrealized losses less than 12 months, trading	0
Unrealized losses 12 months or greater, trading	7,953
Total, trading	7,953
Gross Unrealized Loss
Unrealized losses less than 12 months, trading	0
Unrealized losses 12 months or greater, trading	(583)
Total, trading	(583)
Foreign government bonds
Fair Value
Unrealized losses less than 12 months, available for sale	46,218
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	46,218
Gross Unrealized Loss
Unrealized losses less than 12 months, available for sale	(12)
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	(12)
Corporate notes and bonds
Fair Value
Unrealized losses less than 12 months, available for sale	478,124
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	478,124
Gross Unrealized Loss
Unrealized losses less than 12 months, available for sale	(392)
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	(392)
Mortgage backed securities — residential
Fair Value
Unrealized losses less than 12 months, available for sale	4,912
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	4,912
Gross Unrealized Loss
Unrealized losses less than 12 months, available for sale	(15)
Unrealized losses 12 months or greater, available for sale	0
Total, available for sale	$ (15)

Available-for-sale and Trading Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss

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