Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Millions		Apr. 01, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		$ 1,085	$ 2,150
Total assets	[1]	164,612	171,797
Total liabilities		1,003	691
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		15,188	24,937
Total liabilities		1,003	691
Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		1,085	2,150
Available-for-sale debt securities		7,006	15,362
Total short-term investments		8,091	17,512
Other Current Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		289	337
Other Current Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		93	104
Other Current Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		196	234
Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	1,497	1,440
Available-for-sale debt securities		4,833	5,090
Trading securities, debt		60	73
Trading funds and securities		1,557	1,514
Total long-term investments		6,390	6,603
Other Noncurrent Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		418	484
Other Noncurrent Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		325	477
Other Noncurrent Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		92	7
Other Current Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		389	201
Other Current Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		2	1
Other Current Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		387	201
Other Noncurrent Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		614	490
Other Noncurrent Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		424	177
Other Noncurrent Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		190	313
Level 1 [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		1,590	1,523
Total liabilities		0	0
Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		20	16
Available-for-sale debt securities		0	0
Total short-term investments		20	16
Level 1 [Member] | Other Current Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		0	0
Level 1 [Member] | Other Current Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		0	0
Level 1 [Member] | Other Current Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		0	0
Level 1 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	1,465	1,398
Available-for-sale debt securities		46	36
Trading securities, debt		60	73
Trading funds and securities		1,525	1,472
Total long-term investments		1,571	1,507
Level 1 [Member] | Other Noncurrent Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		0	0
Level 1 [Member] | Other Noncurrent Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		0	0
Level 1 [Member] | Other Noncurrent Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		0	0
Level 1 [Member] | Other Current Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		0	0
Level 1 [Member] | Other Current Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		0	0
Level 1 [Member] | Other Current Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		0	0
Level 1 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		0	0
Level 1 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		0	0
Level 1 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		0	0
Level 2 [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		13,597	23,414
Total liabilities		1,003	691
Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		1,065	2,134
Available-for-sale debt securities		7,006	15,362
Total short-term investments		8,071	17,496
Level 2 [Member] | Other Current Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		289	337
Level 2 [Member] | Other Current Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		93	104
Level 2 [Member] | Other Current Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative assets		196	234
Level 2 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	32	42
Available-for-sale debt securities		4,787	5,054
Trading securities, debt		0	0
Trading funds and securities		32	42
Total long-term investments		4,819	5,096
Level 2 [Member] | Other Noncurrent Assets [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		418	484
Level 2 [Member] | Other Noncurrent Assets [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		325	477
Level 2 [Member] | Other Noncurrent Assets [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative assets		92	7
Level 2 [Member] | Other Current Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		389	201
Level 2 [Member] | Other Current Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		2	1
Level 2 [Member] | Other Current Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current derivative liabilities		387	201
Level 2 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		614	490
Level 2 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member] | Interest rate contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		424	177
Level 2 [Member] | Other Noncurrent Liabilities [Member] | Recurring [Member] | Foreign exchange contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Noncurrent derivative liabilities		190	313
Money market funds [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		1,054	2,115
Money market funds [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		0	0
Money market funds [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities		1,054	2,115
Equity [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	31	35
Equity [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	20	16
Equity [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	[2]	11	19
Government and agency - non U.S. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		3,617	12,629
Government and agency - non U.S. [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		3,370	12,242
Government and agency - non U.S. [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		247	387
Government and agency - non U.S. [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Government and agency - non U.S. [Member] | Level 1 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Government and agency - non U.S. [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		3,370	12,242
Government and agency - non U.S. [Member] | Level 2 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		247	387
Corporate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	[3]	7,685	6,938
Corporate [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		3,581	2,766
Corporate [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		4,103	4,172
Corporate [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Corporate [Member] | Level 1 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		46	36
Corporate [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		3,581	2,766
Corporate [Member] | Level 2 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		4,058	4,136
Government - U.S. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		466	747
Government - U.S. [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	252
Government - U.S. [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		465	495
Government - U.S. [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Government - U.S. [Member] | Level 1 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Government - U.S. [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	252
Government - U.S. [Member] | Level 2 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		465	495
Agency asset-backed - U.S. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		22	24
Agency asset-backed - U.S. [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		22	23
Agency asset-backed - U.S. [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Agency asset-backed - U.S. [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		22	23
Other asset-backed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities	[4]	50	114
Other asset-backed [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		33	79
Other asset-backed [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		17	35
Other asset-backed [Member] | Level 1 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Other asset-backed [Member] | Level 1 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		0	0
Other asset-backed [Member] | Level 2 [Member] | Short-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		33	79
Other asset-backed [Member] | Level 2 [Member] | Long-term Investments [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale debt securities		$ 17	$ 35

[1] Amounts may not add due to rounding.

[2] As of April 1, 2018 and December 31, 2017, equity securities of $31 million and $42 million, respectively, are held in trust for benefits attributable to the former Pharmacia Savings Plus Plan.

[3] Issued by a diverse group of corporations.

[4] Includes loan-backed, receivable-backed and mortgage-backed securities, all of which are in senior positions in the capital structure of the security. Loan-backed securities are collateralized by senior secured obligations of a diverse pool of companies or student loans and receivable-backed securities are collateralized by credit cards receivables. Mortgage-backed securities are collateralized by diversified pools of residential and commercial mortgages.