Commitments and Contingencies - Additional Information (Detail)	Sep. 28, 2019 USD ($)
Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	$ 31,596,000
Non-Current Investments
Commitments and Contingencies Disclosure [Line Items]
Total non-current investments	85,460,000
Non-Current Investments | Collateral Pledged [Member]
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	36,741,000
Revolving Credit Facility
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	34,368,000
Guarantee Payment of Insurance Claims
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	$ 61,503,000