Investments (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 28, 2019	Dec. 29, 2018
Investments [Abstract]
Proceeds from sale of available-for-sale securities	$ 71,000	$ 233,000	$ 45,000
Equity Securities without Readily Determinable Fair Value, Amount	361,000	314,000
Equity Securities with Readily Determinable Fair Value, Amount		14,000
Gain on sale of equity investment	75,834	15,509	0
Unrealized gain on equity investment	0	14,112	$ 0
Equity Method Investments	12,000	$ 9,000
Proceeds from Sale of Debt and Equity Securities, FV-NI, Held-for-investment	$ 90,000

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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The cash inflow associated with the sale of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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