Basis of Presentation - Additional Information (Detail)	9 Months Ended
Sep. 30, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Anticipated completion of divestitures	One year

The initial period in which these effects are expected to be realized.

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4)

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration