FINANCIAL INSTRUMENTS - Schedule of Cash, Cash Equivalents, Investments and Restricted Cash and Investments Unrealized Loss Positions (Details) $ in Thousands	Sep. 23, 2018 USD ($)
Fair Value
Unrealized Losses Less than 12 Months	$ 874,196
Unrealized Losses 12 Months or Greater	46,676
Total	920,872
Gross Unrealized Loss
Unrealized Losses Less than 12 Months	1,470
Unrealized Losses 12 Months or Greater	618
Total	2,088
U.S. Treasury and agencies
Fair Value
Unrealized Losses Less than 12 Months, available for sale	421,723
Unrealized Losses 12 Months or Greater, available for sale	5,880
Total, available for sale	427,603
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	(92)
Unrealized Losses 12 Months or Greater, available for sale	(119)
Total, available for sale	(211)
Municipal notes and bonds
Fair Value
Unrealized Losses Less than 12 Months, available for sale	141,051
Unrealized Losses 12 Months or Greater, available for sale	5,725
Total, available for sale	146,776
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	(534)
Unrealized Losses 12 Months or Greater, available for sale	(47)
Total, available for sale	(581)
Mutual funds
Fair Value
Unrealized Losses Less than 12 Months, trading	17,592
Unrealized Losses 12 Months or Greater, trading	0
Total, trading	17,592
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, trading	83
Unrealized Losses 12 Months or Greater, trading	0
Total, trading	83
Government-sponsored enterprises
Fair Value
Unrealized Losses Less than 12 Months, available for sale	0
Unrealized Losses 12 Months or Greater, available for sale	10,785
Total, available for sale	10,785
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	0
Unrealized Losses 12 Months or Greater, available for sale	(204)
Total, available for sale	(204)
Foreign government bonds
Fair Value
Unrealized Losses Less than 12 Months, available for sale	26,928
Unrealized Losses 12 Months or Greater, available for sale	0
Total, available for sale	26,928
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	(8)
Unrealized Losses 12 Months or Greater, available for sale	0
Total, available for sale	(8)
Corporate notes and bonds
Fair Value
Unrealized Losses Less than 12 Months, available for sale	266,159
Unrealized Losses 12 Months or Greater, available for sale	24,286
Total, available for sale	290,445
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	(751)
Unrealized Losses 12 Months or Greater, available for sale	(248)
Total, available for sale	(999)
Mortgage backed securities — residential
Fair Value
Unrealized Losses Less than 12 Months, available for sale	743
Unrealized Losses 12 Months or Greater, available for sale	0
Total, available for sale	743
Gross Unrealized Loss
Unrealized Losses Less than 12 Months, available for sale	(2)
Unrealized Losses 12 Months or Greater, available for sale	0
Total, available for sale	$ (2)