Schedule of Available for Sale Securities by Contractual Maturity (Detail) $ in Millions	Dec. 27, 2015 USD ($)
Investments Classified by Contractual Maturity Date [Line Items]
Due in one year or less, Amortized Cost	$ 0.2
Due after one year through five years, Amortized Cost	0.7
Due after five years through ten years	0.7
Due after ten years	0.4
Total available for sale securities, Amortized Cost	2.0
Due in one year or less, Fair Value	0.2
Due after one year through five years, Fair Value	0.8
Due after five years through ten years	0.8
Due after ten years	0.4
Total available for sale securities, Fair Value	$ 2.2