Inventories (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Sep. 28, 2013	Dec. 29, 2012
Inventories [Abstract]
Raw materials and supplies			$ 49,705,000	$ 46,114,000
Work-in-process			48,075,000	40,951,000
Finished goods			142,710,000	148,014,000
Valuation reserves			(6,409,000)	(5,645,000)
Inventories			234,081,000	229,434,000
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)	$ 0.13