Inventories (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Dec. 27, 2014	Dec. 28, 2013
Inventories [Abstract]
Raw materials and supplies			$ 53,586,000	$ 54,613,000
Work-in-process			39,707,000	43,796,000
Finished goods			168,481,000	159,422,000
Valuation reserves			(5,189,000)	(6,115,000)
Inventories			256,585,000	251,716,000
Inventories valued using the LIFO method			25,900,000	34,900,000
FIFO cost of inventories			104,800,000	117,900,000
Average cost basis inventories			47,700,000	54,700,000
Deferred LIFO Gain		8,000,000
Effect of liquidation of LIFO layers on cost of sales	8,000,000
Effect of liquidation of LIFO layers per diluted share after tax (in dollars per share)	$ 0.7
FIFO value of inventory consigned to others			$ 4,300,000	$ 4,300,000