| Expected Future Minimum Payment Obligations for Non-Cancelable Operating Leases Exceeding One Year (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2012 | 
|---|---|
| Operating Leased Assets [Line Items] | |
| 2013 | $ 20.7 | 
| 2014 | 15.0 | 
| 2015 | 11.7 | 
| 2016 | 8.0 | 
| 2017 | 6.1 | 
| Thereafter | 32.8 | 
| Total debt | $ 94.3 | 
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- Details 
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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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