Share-Based Compensation - Unrecognized Share Based Compensation Expense (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 6.0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	1.1
Weighted average years expected to recognize compensation (in years)	2 years 3 months 18 days
Performance-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	1.6
Weighted average years expected to recognize compensation (in years)	2 years 3 months 18 days
Time-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 3.3
Weighted average years expected to recognize compensation (in years)	1 year 8 months 12 days