Commitments and Contingencies - Schedule of Liabilities for Future Environmental Costs (Detail) $ in Millions	Sep. 28, 2018 USD ($)
Loss Contingencies [Line Items]
2019	$ 1.1
2020	0.8
2021	0.7
2022	0.6
2023	0.8
Thereafter	2.0
Total costs	6.0
Less imputed interest	0.6
Reserve amount	5.4
Recurring Costs
Loss Contingencies [Line Items]
2019	0.5
2020	0.5
2021	0.4
2022	0.4
2023	0.4
Thereafter	1.1
Total costs	3.3
Non-Recurring Costs
Loss Contingencies [Line Items]
2019	0.6
2020	0.3
2021	0.3
2022	0.2
2023	0.4
Thereafter	0.9
Total costs	$ 2.7