Assets Measured at Fair Value on a Nonrecurring Basis (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total, impairment charge	$ 6.6	$ 4.1
Fair Value, Measurements, Nonrecurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-lived assets held and used, impairment charge	4.7	3.6
Long-lived assets held for sale or disposal, impairment charge	1.9	1.1
Total, impairment charge	6.6	4.7
Long-lived assets held and used, net book value	5.7	1.6
Long-lived assets held for sale or disposal, net book value	3.9
Total Assets	9.6	1.6
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Long-lived assets held and used, fair value measurement	5.8	1.6
Long-lived assets held for sale or disposal, fair value measurement	4.2	0.4
Total, fair value measurement	$ 10.0	$ 2.0