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	Jul. 01, 2018	Dec. 31, 2017	Jul. 02, 2017	Jan. 01, 2017
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Estimated Fair Value	$ 9,031	$ 5,310
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	17,569	17,824	$ 12,598	$ 18,972
Marketable securities	570	$ 472
Held-to-maturity Securities
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	9,108
Held-to-maturity Securities - Estimated Fair Value	9,108
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	9,108
Marketable securities	0
Held-to-maturity Securities \| Cash
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,473
Held-to-maturity Securities - Estimated Fair Value	2,473
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,473
Held-to-maturity Securities \| Other sovereign securities(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	180
Held-to-maturity Securities - Estimated Fair Value	180
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	180
Marketable securities
Held-to-maturity Securities \| U.S. reverse repurchase agreements
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,425
Held-to-maturity Securities - Estimated Fair Value	2,425
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,425
Marketable securities
Held-to-maturity Securities \| Other reverse repurchase agreements
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	425
Held-to-maturity Securities - Estimated Fair Value	425
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	425
Held-to-maturity Securities \| Corporate debt securities(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	0
Held-to-maturity Securities - Estimated Fair Value	0
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	0
Marketable securities	0
Held-to-maturity Securities \| Money market funds
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	2,507
Held-to-maturity Securities - Estimated Fair Value	2,507
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	2,507
Held-to-maturity Securities \| Time deposits(1)
Held-to-maturity Securities [Abstract]
Held-to-maturity Securities - Carrying Amount	1,098
Held-to-maturity Securities - Estimated Fair Value	1,098
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	1,098
Available-for-sale Securities
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	9,031
Available-for-sale Securities - Estimated Fair Value	9,031
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	8,461
Marketable securities	570
Available-for-sale Securities \| Other sovereign securities(1)
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	0
Available-for-sale Securities - Estimated Fair Value	0
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	0
Marketable securities	0
Available-for-sale Securities \| Corporate debt securities(1)
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	265
Available-for-sale Securities - Estimated Fair Value	265
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	24
Marketable securities	241
Available-for-sale Securities \| US Treasury and Government [Member]
Available-for-sale Securities [Abstract]
Available-for-sale Securities - Carrying Amount	8,766
Available-for-sale Securities - Estimated Fair Value	8,766
Available-for-sale Securities and Held-to-maturity Securities [Abstract]
Cash and Cash Equivalents	8,437
Marketable securities	$ 329