Share-Based Compensation - Share-Based Compensation Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Oct. 01, 2011	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 4.9	$ 2.9	$ 4.7
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		0.4		1.0
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense				0.2
Performance-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	3.3	0.7	(1.2)	1.4
Time-Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		3.1	3.4	1.3
Director Share Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		0.7	0.7	0.7
Share appreciation rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense				$ 0.1