Joint Ventures and Other Equity Method Affiliates - Summarized Financial Information for AZLP (Detail) (AstraZeneca LP [Member], USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
AstraZeneca LP [Member]
Equity Income from Affiliates [Line Items]
Sales	$ 1,232	$ 1,124	$ 3,424	$ 3,460
Materials and production costs	561	464	1,520	1,524
Other expense, net	204	357	936	1,004
Income before taxes	$ 467	$ 303	$ 968	$ 932

This item represents the disclosure of summarized financial information for unconsolidated subsidiaries and 50 percent-or-less owned entities accounted for using the equity method of accounting. If investments in common stock of corporate joint ventures or other investments accounted for under the equity method are, in the aggregate, material in relation to the financial position or results of operations of an investor, it may be necessary to present summarized information as to assets of the investee, or group of investments for which combined disclosure is appropriate, either by individual financial statement caption or in groups, as appropriate. Such summarized financial information may, at a minimum, include income or loss before taxes.

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