SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Other Assets (Details) - USD ($) $ in Thousands	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
Venture capital investments	$ 197,100	$ 108,983
Strategic equity investments	24,704	13,996
Cash surrender value of life insurance policies	43,827	38,207
Other long-term income tax assets	23,485	20,570
Restricted cash	1,621	1,601	$ 1,411
Long-term pension assets	31,915	1,741
Other	29,974	27,517
Other assets	$ 352,626	$ 212,615

Pension Plan Assets, Non-Current

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and other assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of investment in equity security without readily determinable fair value.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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