Commitments and Contingencies - Additional Information (Detail)	Sep. 26, 2020 USD ($)
Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	$ 39,068,000
Non-Current Investments
Commitments and Contingencies Disclosure [Line Items]
Total non-current investments	82,734,000
Non-Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	26,969,000
Revolving Credit Facility
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	33,618,000
Guarantee Payment of Insurance Claims
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	$ 59,434,000