Quarterly Financial Information (Unaudited) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly financial information [Line Items]
Net sales	$ 3,707	$ 3,935	$ 4,082	$ 3,636	$ 3,500	$ 3,774	$ 3,883	$ 3,108	$ 15,360	$ 14,265	$ 12,686
Cost of Sales	2,165	2,229	2,306	2,091	2,028	2,161	2,263	1,862	8,791	8,314	7,599
Continuing operations	86	377	393	277	237	204	318	191	1,133	950	663
Discontinued operations	(3)	(6)	(7)	985	17	22	23	2,219	969	2,281	278
Continuing operations (in dollars per share)	$ 0.63	$ 2.73	$ 2.83	$ 1.99	$ 1.68	$ 1.43	$ 2.22	$ 1.31	$ 8.19	$ 6.62	$ 4.32
Discontinued operations (in dollars per share)	$ (0.02)	$ (0.04)	$ (0.05)	$ 7.08	$ 0.12	$ 0.15	$ 0.16	$ 15.18	$ 7.01	$ 15.91	$ 1.81
Income from continuing operations, net of tax	$ 83	$ 371	$ 386	$ 1,262	$ 254	$ 226	$ 341	$ 2,410	$ 2,102	$ 3,231	$ 941
Earnings per common share (in dollars per share)	$ 0.61	$ 2.69	$ 2.78	$ 9.07	$ 1.80	$ 1.58	$ 2.38	$ 16.49	$ 15.20	$ 22.53	$ 6.13
Continuing operations (in dollars per share)	$ 0.62	$ 2.70	$ 2.80	$ 1.97	$ 1.66	$ 1.41	$ 2.19	$ 1.29	$ 8.10	$ 6.55	$ 4.27
Discontinued operations (in dollars per share)	$ (0.02)	$ (0.04)	$ (0.05)	$ 7.00	$ 0.12	$ 0.15	$ 0.16	$ 15.02	$ 6.93	$ 15.72	$ 1.79
Earnings per common share - assuming dilution (in dollars per share)	$ 0.60	$ 2.66	$ 2.75	$ 8.97	$ 1.78	$ 1.56	$ 2.35	$ 16.31	$ 15.03	$ 22.27	$ 6.06