Cash And Cash Equivalents Plan Assets

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- Definition

Common stock held by pension plan, shares

+ References

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- Definition

Defined benefit plan, additional cost contribution

+ References

No definition available.

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- Definition

Defined Benefit Plan Fair Value Of Investments

+ References

No definition available.

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- Definition

Defined Benefit Plan, Interest Rate Used Calculating Annual Transition Pension Adjustment After Specific Completed Period Of Service.

+ References

No definition available.

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- Definition

Defined benefit plan, interest rate used calculating annual transition pension adjustment for specified completed period of service

+ References

No definition available.

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- Definition

Defined benefit plan, interest rate used calculating annual transition pension adjustment, thereafter

+ References

No definition available.

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- Definition

Defined Benefit Plan, Maximum Percentage Contributed By Employer

+ References

No definition available.

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- Definition

Percentage of unrecognized net actuarial gains (losses) as projected benefit obligation, amortized as component of net periodic pension cost

+ References

No definition available.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

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-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

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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.

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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Pension Plans - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	1 Months Ended	6 Months Ended	12 Months Ended
	Jan. 04, 2010	Jan. 04, 2010	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jan. 01, 2005 Y
Retirement Plans [Line Items]
Interest rate used calculating annual transition pension adjustment for specified completed period of service							5.00%
Defined benefit plan, interest rate used calculating annual transition pension adjustment after specific completed period of service							35
Interest rate used calculating annual transition pension adjustment, thereafter							3.00%
Discretionary contributions by employers	$ 100.0	$ 100.0
Common stock held by pension plan, shares				466,755	466,755
Maximum percentage contributed by employer				6.00%	6.00%	6.00%
Defined contribution plan expense				17.9	17.8	16.5
Additional cost contribution			2.4	4.8
Minimum
Retirement Plans [Line Items]
Percentage of unrecognized net actuarial gains (losses) as projected benefit obligation, amortized as component of net periodic pension cost				10.00%
United States Qualified Pension Plans
Retirement Plans [Line Items]
Funded status of the plans			3.9	(15.4)	3.9
Fair value of total plan asset			574.7	591.6	574.7	547.8
Chaucer Pension Scheme
Retirement Plans [Line Items]
Discretionary contributions by employers				4.5	1.0
Funded status of the plans			(30.1)	(25.7)	(30.1)
Expected rate of return on plan assets			7.40%	7.50%
Total Fixed Income and Equity Securities			100.00%	100.00%	100.00%
Fair value of total plan asset			74.3	90.9	74.3	82.1
Invested assets, fair value			74.1	90.7	74.1
Cash and cash equivalents, fair value			0.2	0.2	0.2
Estimated future contributions in next fiscal year				4.5
Chaucer Pension Scheme \| Equity Securities
Retirement Plans [Line Items]
Total Fixed Income and Equity Securities			10.00%	9.00%	10.00%
Invested assets, fair value			57.9	69.6	57.9
U.S. Defined Benefit Plans
Retirement Plans [Line Items]
Expected rate of return on plan assets				6.00%
Total Fixed Income and Equity Securities			100.00%	100.00%	100.00%
Fair value of total plan asset			574.7	591.6	574.7
Invested assets, fair value			568.8	586.6	568.8
Cash and cash equivalents, fair value			5.9	5.0	5.9
Estimated future contributions in next fiscal year				3.1
U.S. Defined Benefit Plans \| Fixed Income Securities
Retirement Plans [Line Items]
Total Fixed Income and Equity Securities			82.00%	84.00%	82.00%
U.S. Defined Benefit Plans \| Equity Securities
Retirement Plans [Line Items]
Total Fixed Income and Equity Securities			18.00%	16.00%	18.00%
Invested assets, fair value			$ 102.9	$ 95.2	$ 102.9