Commitments and Contingencies - Additional Information (Detail)	Sep. 26, 2015 USD ($)
Revolving Credit Facility
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	$ 32,759,000
Guarantee Payment Of Insurance Claims
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	63,210,000
Current Investments
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	48,955,000
Non-Current Investments
Commitments and Contingencies Disclosure [Line Items]
Investments providing collateral for letters of credit to guarantee insurance claims	21,279,000
Total non-current investments	$ 59,356,000