Other Financial Data (Investments) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Dec. 31, 2015	Apr. 02, 2016
Available-for-sale securities:
Cost Basis	$ 462	$ 59
Unrealized Gains	6	2
Unrealized (Loss)	(11)
Investments	457	61
Other investments, at cost	203	204
Equity method investments	9	10
Investments, Cost Basis	674	273
Investments	669	275
Less: current portion of available-for-sale securities	438	47
Long-term investments noncurrent	231	228
Government, agency, and government-sponsored enterprise obligations
Available-for-sale securities:
Cost Basis	455	52
Unrealized Gains	0	0
Unrealized (Loss)	(11)
Investments	444	52
Corporate bonds
Available-for-sale securities:
Cost Basis	7	7
Unrealized Gains	0	0
Unrealized (Loss)	0
Investments	7	7
Common stock
Available-for-sale securities:
Cost Basis	0	0
Unrealized Gains	6	2
Unrealized (Loss)	0
Investments	6	2
United Kingdom Treasury Securities
Available-for-sale securities:
Payments to acquire marketable securities	$ 401
Realized loss on sale of securities		$ 19

Investments, Amortized Cost

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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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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Sum of the carrying amounts as of the balance sheet date of all investments.

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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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Cash outflow for purchase of trading, available-for-sale securities and held-to-maturity securities.

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