Accumulated Other Comprehensive Loss - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Comprehensive income (loss)	$ 13.6	$ 13.6
Reclassified Comprehensive income (loss), Before tax	0.1	0.2
Other comprehensive income Pension liability, tax expense	$ 5.2	$ 4.2

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

+ References

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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

-Publisher FASB

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