Stockholders Equity (detail) - USD ($)	6 Months Ended	12 Months Ended
	Sep. 26, 2015	Sep. 26, 2015	Mar. 31, 2015	Sep. 27, 2014
Treasury Stock, Value, Acquired, Cost Method		$ 25,941,000
Treasury Stock, at cost	$ 62,913,000	62,913,000	$ 61,277,000	$ 39,095,000
Class B Common Stock Converted To Class Aa Common [Member]
Treasury Stock, Value, Acquired, Cost Method	$ 2,000
Stock Repurchased During Period, Shares	60
Treasury Stock [Member]
Treasury Stock, at cost	$ 62,913,000	$ 62,913,000
Shares, Issued	2,203,774	2,203,774
Common Stock [Member]
Treasury Stock, Value, Acquired, Cost Method	$ 1,634,000
Stock Repurchased During Period, Shares	57,400