The Company and Significant Accounting Policies - Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Interest Rate Swap Agreements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate	$ 5.3
Total Fair Value and Carrying Value on Balance Sheet | Contingent Consideration
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate	0.3	1.3
Total Fair Value and Carrying Value on Balance Sheet | Interest Rate Swap Agreements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate	5.3	3.4
Level 2 | Interest Rate Swap Agreements
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate	5.3	3.4
Level 3 | Contingent Consideration
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of interest rate	$ 0.3	$ 1.3