Discontinued Operations - Summary of Major Categories of Cash Flows from Discontinued Operations (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Discontinued Operations And Disposal Groups [Abstract]
Net cash provided by operating activities		$ 36
Net cash provided by investing activities	0	0
Net cash provided by financing activities	0	0
Net cash used for discontinued operations		$ 36

Amount of cash inflow (outflow) of financing activities of discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3521-108585

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- Definition

Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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- Definition

Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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- Definition

Increase (decrease) in cash associated with the entity's discontinued operations.

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