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

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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 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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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

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Fair Value Measurements - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Apr. 01, 2018	Dec. 31, 2017	Apr. 02, 2017	Jan. 01, 2017
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 2,967	$ 5,310
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	14,639	17,824	$ 20,909	$ 18,972
Marketable securities	565	$ 472
Held-to-maturity Securities
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	12,237
Held-to-maturity Securities - Estimated Fair Value	12,237
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	12,232
Marketable securities	5
Held-to-maturity Securities \| Cash
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,656
Held-to-maturity Securities - Estimated Fair Value	2,656
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,656
Held-to-maturity Securities \| Other Sovereign Securities(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	529
Held-to-maturity Securities - Estimated Fair Value	529
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	529
Marketable securities
Held-to-maturity Securities \| U.S. Reverse repurchase agreements
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,682
Held-to-maturity Securities - Estimated Fair Value	2,682
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,682
Marketable securities
Held-to-maturity Securities \| Other Reverse repurchase agreements
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	398
Held-to-maturity Securities - Estimated Fair Value	398
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	398
Held-to-maturity Securities \| Corporate debt securities(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	1,869
Held-to-maturity Securities - Estimated Fair Value	1,869
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	1,864
Marketable securities	5
Held-to-maturity Securities \| Money market funds
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,944
Held-to-maturity Securities - Estimated Fair Value	2,944
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,944
Held-to-maturity Securities \| Time deposits(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	1,159
Held-to-maturity Securities - Estimated Fair Value	1,159
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	1,159
Available-for-sale Securities
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	2,967
Available-for-sale Securities - Estimated Fair Value	2,967
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,407
Marketable securities	560
Available-for-sale Securities \| Other Sovereign Securities(1)
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	2
Available-for-sale Securities - Estimated Fair Value	2
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	0
Marketable securities	2
Available-for-sale Securities \| Corporate debt securities(1)
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	260
Available-for-sale Securities - Estimated Fair Value	260
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	37
Marketable securities	223
Available-for-sale Securities \| US Treasury and Government [Member]
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	2,705
Available-for-sale Securities - Estimated Fair Value	2,705
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,370
Marketable securities	$ 335