Accumulated Benefit Obligations in Excess of Plan Assets (Detail) (Pension Plans, Defined Benefit, USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 3,912.0	$ 4,321.6
Fair value of plan assets	$ 3,672.6	$ 3,187.4

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=32704760&loc=d3e4179-114921

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant