Schedule II - Valuation And Qualifying Accounts - Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance as of Beginning of Period	$ 677.1	$ 663.6	$ 1,428.0
Additions	48.9	66.7	96.1
Retirements	(127.0)	(69.4)	(875.9)
Other Changes	(63.0)	16.2	15.4
Balance as of End of Period	536.0	677.1	663.6
Allowance for doubtful accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance as of Beginning of Period	34.5	35.4	30.7
Additions	7.6	11.8	5.9
Retirements	(10.0)	(13.9)	(4.2)
Other Changes	(4.6)	1.2	3.0
Balance as of End of Period	27.5	34.5	35.4
Allowance for deferred tax assets
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance as of Beginning of Period	642.6	628.2	1,397.3
Additions	41.3	54.9	90.2
Retirements	(117.0)	(55.5)	(871.7)
Other Changes	(58.4)	15.0	12.4
Balance as of End of Period	$ 508.5	$ 642.6	$ 628.2

Total of the adjustments in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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