XML 70 R59.htm IDEA: XBRL DOCUMENT v3.7.0.1
Marketable Securities - Reconciles Cost Basis to Fair Market Value of Company's Equity Security (Detail) - Equity securities - USD ($)
$ in Millions
Jul. 01, 2017
Sep. 24, 2016
Schedule Of Marketable Securities [Line Items]    
Available-for-sale Equity Securities, Amortized Cost Basis $ 0.7 $ 2.4
Gross Unrealized Gains 0.0 0.0
Gross Unrealized Losses (0.5) (0.3)
Other than temporary impairment 0.0 (1.1)
Fair Value $ 0.2 $ 1.0