Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	$ 138	$ 111	$ 111
Cash payments	(32)		(74)
Restructuring charges	276		286
Other	134		185
Restructuring reserve ending balance	248		138
Restructuring and other charges	461	7
Layoff Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	96	59	59
Cash payments	(29)		(63)
Restructuring charges	146		201
Other	5		101
Restructuring reserve ending balance	208		96
Restructuring and other charges	13	3
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	42	52	52
Cash payments	(3)		(11)
Restructuring charges	130		85
Other	129		84
Restructuring reserve ending balance	40		42
Restructuring and other charges	336
Asset Retirement Obligations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	55		12
Environmental Remediation [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	42		58
Pension Costs [Member]
Restructuring Cost and Reserve [Line Items]
Other			$ 92