Summary of Pre-Tax Amounts Recognized in Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Schedule Of Pension And Other Retirement Benefits Recognized In Accumulated Other Comprehensive Income Loss [Line Items]
Amortization of net actuarial losses		$ 9.1
Pension Plans
Schedule Of Pension And Other Retirement Benefits Recognized In Accumulated Other Comprehensive Income Loss [Line Items]
Amortization of net actuarial losses	10.8
Amortization of prior service costs	(0.6)	(0.7)
Accelerated recognition of actuarial loss due to settlement		0
Net actuarial loss arising during the period		(24.7)
Total recognized in OCI - pre-tax		(14.9)
Other Retirement Plans
Schedule Of Pension And Other Retirement Benefits Recognized In Accumulated Other Comprehensive Income Loss [Line Items]
Amortization of net actuarial losses	0.3	0.3
Amortization of prior service costs	0	0
Accelerated recognition of actuarial loss due to settlement		0
Net actuarial loss arising during the period		(0.2)
Total recognized in OCI - pre-tax		$ 0.1

Before tax amount of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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-Section 45

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

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 7

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 17, 19, 24

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 4

-Subparagraph c, d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Before tax amount of the gain (loss) adjustment to other comprehensive income (loss) resulting from the settlement or curtailment of the entity's defined benefit pension and other postretirement plans.

+ References+ Details