Retirement Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012 Y	Dec. 31, 2011 Y	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Expected period of return on plan assets, years	10	10
Minimum contribution by employer		$ 0.3	$ 0.3
Discretionary contributions by employer	7.2	7.2	6.5
Fair value of plan assets	227.4	202.9	199.7
Postretirement benefit obligation and unfunded status of plan	292.0	267.1	220.0
Net periodic postretirement benefit cost	(4.2)	1.0	(0.3)
Foreign Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	16.0	12.3	7.8
Matching contributions by employer, percentage	100.00%
Additional percentage of eligible compensation for matching contributions by employer	5.00%
Qualified Contributory Savings and Thrift 401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	33.0	30.5	28.7
Matching contributions by employer, percentage	100.00%
Nonqualified Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	2.5	2.1	2.0
Fair value of plan assets	116.7	95.5
Retiree Health Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefit obligation and unfunded status of plan	3.1	3.2
Net periodic postretirement benefit cost	$ (0.1)	$ 0.1	$ 0.1

Defined benefit plan, additional percentage of eligible compensation for matching contributions by employer

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- Definition

Defined benefit plan, discretionary contributions by employer

+ References

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Defined benefit plan, matching contributions by employer, percentage

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- Definition

Defined benefit plan, minimum contribution by employer

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Defined benefit plan, percentage of eligible compensation for matching contributions by employer

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- Definition

Expected period of return on plan assets

+ References

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 6

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-Topic 715

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

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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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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-Name Statement of Financial Accounting Standard (FAS)

-Number 87

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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 total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- Definition

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

+ References

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