Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2013
Income Tax Disclosure [Abstract]
Cumulative undistributed foreign corporate earnings	$ 97.5	$ 97.5
Unrecognized tax benefits	3.3	3.3
Accrued interest related to uncertain tax positions	0.5	0.5
Charges with respect to interest and penalties	$ 0	$ 0

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount of interest expense accrued for an underpayment of income taxes.

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