CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (USD $) In Thousands, unless otherwise specified	Common Shares	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Non-Controlling Interests	Total
Balance at Apr. 28, 2012	$ 52,244	$ 231,332	$ 189,609	$ (31,281)	$ 5,911	$ 447,815
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			46,389		793	47,182
Other comprehensive income (loss)				(4,215)	339	(3,876)
Stock issued for stock and employee benefit plans, net of cancellations and withholding tax	817	1,849	(1,368)			1,298
Purchases of common stock	(669)	(5,314)	(4,350)			(10,333)
Stock option and restricted stock expense		11,458				11,458
Tax benefit from exercise of options		2,563				2,563
Dividends paid			(4,236)			(4,236)
Change in noncontrolling interests					97	97
Balance at Apr. 27, 2013	52,392	241,888	226,044	(35,496)	7,140	491,968
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			55,056		1,324	56,380
Other comprehensive income (loss)				4,116	(730)	3,386
Stock issued for stock and employee benefit plans, net of cancellations and withholding tax	937	2,395	(4,509)			(1,177)
Purchases of common stock	(1,348)	(3,056)	(27,693)			(32,097)
Stock option and restricted stock expense		8,739				8,739
Tax benefit from exercise of options		12,935				12,935
Dividends paid			(10,514)			(10,514)
Change in noncontrolling interests					98	98
Balance at Apr. 26, 2014	51,981	262,901	238,384	(31,380)	7,832	529,718
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			70,773		1,198	71,971
Other comprehensive income (loss)				(759)	(76)	(835)
Stock issued for stock and employee benefit plans, net of cancellations and withholding tax	898	26	(10,684)			(9,760)
Purchases of common stock	(2,132)	(1,267)	(48,454)			(51,853)
Stock option and restricted stock expense		6,780				6,780
Tax benefit from exercise of options		1,592				1,592
Dividends paid			(14,513)			(14,513)
Balance at Apr. 25, 2015	$ 50,747	$ 270,032	$ 235,506	$ (32,139)	$ 8,954	$ 533,100