Debt Instruments (detail) (USD $)	3 Months Ended		6 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Debt Instruments [Abstract]
Line of Credit Facility, Amount Outstanding	$ 233,000,000	$ 237,413,000	$ 233,000,000	$ 237,413,000
Debt, Weighted Average Interest Rate	1.47%	1.73%	1.47%	1.73%
Line of Credit Facility, Maximum Amount Outstanding During Period	234,000,000	243,067,000	234,000,000	243,067,000
Line of Credit Facility, Average Outstanding Amount	152,537,000	159,968,000	132,009,000	138,240,000
Debt Instrument, Interest Rate During Period	1.50%	1.62%	1.54%	1.47%
August through March [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	350,000,000		350,000,000
April through July [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 250,000,000		$ 250,000,000