Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail)

v3.3.1.900
Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Dec. 26, 2015
Sep. 26, 2015
Dec. 27, 2014
Assets:      
Total assets     $ 9,992
Liabilities:      
Total liabilities $ 5,625 $ 3,625 4,414
Liability for Contingent Consideration [Member]      
Liabilities:      
Total liabilities 5,625 3,625 4,414
Short Term Investments [Member]      
Assets:      
Total assets     9,992
Level 1 [Member]      
Assets:      
Total assets     9,992
Liabilities:      
Total liabilities 0 0 0
Level 1 [Member] | Liability for Contingent Consideration [Member]      
Liabilities:      
Total liabilities 0 0 0
Level 1 [Member] | Short Term Investments [Member]      
Assets:      
Total assets     9,992
Level 2 [Member]      
Assets:      
Total assets     0
Liabilities:      
Total liabilities 0 0 0
Level 2 [Member] | Liability for Contingent Consideration [Member]      
Liabilities:      
Total liabilities 0 0 0
Level 2 [Member] | Short Term Investments [Member]      
Assets:      
Total assets     0
Level 3 [Member]      
Assets:      
Total assets     0
Liabilities:      
Total liabilities 5,625 3,625 4,414
Level 3 [Member] | Liability for Contingent Consideration [Member]      
Liabilities:      
Total liabilities $ 5,625 $ 3,625 4,414
Level 3 [Member] | Short Term Investments [Member]      
Assets:      
Total assets     $ 0