Share-Based Compensation - Share-Based Compensation Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1.1	$ 1.3	$ 3.6	$ 3.5
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	0.2	0.1	0.6	0.3
Directors' Share Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			0.8	0.7
Performance-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	0.3	0.2	0.7	0.4
Time-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 0.6	$ 1.0	$ 1.5	$ 2.1