Quarterly report pursuant to Section 13 or 15(d)

Accounting for Uncertainty in Income Taxes - Additional Information (Detail)

v2.4.0.8
Accounting for Uncertainty in Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended 12 Months Ended
Jun. 30, 2013
Dec. 31, 2012
Jun. 30, 2012
Income Tax Disclosure [Abstract]      
Liability for unrecognized tax $ 10.1   $ 14.8
Unrecognized tax favorable impact on effective tax rate 3.3   6.9
Accrued interest and penalties applied to uncertain tax positions $ 7.6 $ 7.0