Summary of Amounts Reclassification from AOCI to Net Income (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of pension and other employee benefits items Actuarial losses and other reclassified from AOCI to net income, before tax	[1]	$ (130)		$ (181)
Amortization of pension and other employee benefits items Actuarial losses and other reclassified from AOCI to net income, tax benefit	[1]	36		61
Amortization of pension and other employee benefits items Actuarial losses and other reclassified from AOCI to net income, net of tax	[1]	(94)		(120)
Gains (losses) on hedging activities reclassified from AOCI to net income, before tax	[1]	6		47
Gains (losses) on hedging activities reclassified from AOCI to net income, tax expense	[1]	(1)		(16)
Gains (losses) on hedging activities reclassified from AOCI to net income, net of tax		5	[1]	31	[1]	$ 8
Gain (loss) on sale of available-for-sale equity securities and other-than-temporary impairment of available-for-sale equity securities, before tax	[1]	4,536		38
Gain (loss) on sale of available-for-sale equity securities and other-than-temporary impairment of available-for-sale equity securities, tax expense	[1]			(15)
Gain (loss) on sale of available-for-sale equity securities and other-than-temporary impairment of available-for-sale equity securities, net of tax	[1]	4,536		23
Total reclassification for the period	[1]	4,447		(66)
Other (income) expense, net | Equity securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains (loss) on available for sale securities sale reclassified from AOCI to net income, before tax	[1]	4,536		38
Interest rate contract | Other (income) expense, net
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains (losses) on hedging activities reclassified from AOCI to net income, before tax	[1]	9
Foreign exchange contract | Cost of Sales
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains (losses) on hedging activities reclassified from AOCI to net income, before tax	[1]	(3)		47
Actuarial losses and other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of pension and other employee benefits items Actuarial losses and other reclassified from AOCI to net income, before tax	[1],[2]	$ (130)		$ (181)

[1] Amounts in parentheses indicate reductions to net income.

[2] These AOCI components are included in the computation of net periodic benefit cost disclosed in Note 13.