Income Taxes - Changes in Valuation Allowance Attributable to Continuing Operations and Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Tax Disclosure [Abstract]
Continuing operations	$ 0.4	$ 0.2	$ (6.8)	$ (4.4)
Other comprehensive income	(6.6)	16.5	(6.8)	11.4
Change in valuation allowance	$ (6.2)	$ 16.7	$ (13.6)	$ 7.0

The amount of the change in the period in the valuation allowance for a specified deferred tax asset.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e32123-109318

Name:	us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration