Cash, Cash Equivalents, and Investments - Components of Cash, Cash Equivalents, and Investments (Details) - USD ($) $ in Thousands	Jul. 04, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Cash	$ 216,837	$ 266,609
Money market instruments	200	2,464
Cash and cash equivalents	217,037	269,073
Current investments	190,747	103,240
Non-current investments	543,965	395,125
Total	951,749	767,438
Treasury Bills
Debt Securities, Available-for-sale [Line Items]
Current investments	92,939	35,403
Long-term investments	38,022	96,458
Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Current investments	66,452	32,714
Long-term investments	415,784	203,428
Asset-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Current investments	24,756	25,160
Long-term investments	65,509	67,058
Agency Bonds
Debt Securities, Available-for-sale [Line Items]
Long-term investments	18,960	19,006
Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Current investments	2,404	1,303
Long-term investments	4,593	5,735
Sovereign Bonds
Debt Securities, Available-for-sale [Line Items]
Current investments	4,196	8,660
Long-term investments	$ 1,097	$ 3,440

Cash, cash equivalents, short term and long term investments.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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