CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (USD $) In Thousands, unless otherwise specified	Common Shares [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Non-Controlling Interests [Member]	Total
Balance at Apr. 30, 2011	$ 51,909	$ 222,339	$ 105,872	$ (18,804)	$ 2,824	$ 364,140
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			87,966		942	88,908
Other comprehensive income (loss)				(12,477)	(167)	(12,644)
Stock issued for stock and employee benefit plans, net of cancellations	835	4,011	(509)			4,337
Purchases of common stock	(500)	(958)	(3,721)			(5,179)
Stock option and restricted stock expense		5,717	1			5,718
Tax benefit from exercise of options		223				223
Dividends paid						0
Change in noncontrolling interests					2,312	2,312
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	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	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