Inventories - Components of Inventories (Detail) - USD ($)
$ in Thousands
Mar. 28, 2015
Dec. 27, 2014
Dec. 28, 2013
Inventory Disclosure [Abstract]      
Aggregate stockpiles $ 90,000 $ 88,211 $ 70,300
Finished goods 18,355 8,826 11,207
Work in process 2,065 1,801 2,623
Raw materials 22,887 12,715 12,302
Total $ 133,307 $ 111,553 $ 96,432