Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2022	Apr. 24, 2021	Apr. 25, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 782,146	$ 716,306	$ 696,976
Changes before reclassifications	(4,410)	5,264	(3,363)
Reclassification of certain income tax effects			(547)
Amounts reclassified to net income	365	338	91
Tax effect	(231)	(171)	329
Total other comprehensive income	(4,276)	5,431	(3,490)
Ending balance	819,622	782,146	716,306
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	782,146	716,306	696,976
Net income	152,328	107,529	78,984
Other comprehensive income (loss)	(5,078)	5,965	(3,209)
Other changes in noncontrolling interests			156
Ending balance	819,622	782,146	716,306
Translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	3,041	(1,891)	50
Changes before reclassifications	(5,002)	4,932	(1,941)
Reclassification of certain income tax effects			0
Amounts reclassified to net income	0	0	0
Tax effect	0	0	0
Total other comprehensive income	(5,002)	4,932	(1,941)
Ending balance	(1,961)	3,041	(1,891)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	3,041	(1,891)	50
Ending balance	(1,961)	3,041	(1,891)
Change in fair value of cash flow hedge
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	0	87
Changes before reclassifications	0	0	0
Reclassification of certain income tax effects			(97)
Amounts reclassified to net income	0	0	14
Tax effect	0	0	(4)
Total other comprehensive income	0	0	(87)
Ending balance	0	0	0
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	0	0	87
Ending balance	0	0	0
Unrealized gain (loss) on marketable securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	370	449	6
Changes before reclassifications	(947)	(96)	387
Reclassification of certain income tax effects			258
Amounts reclassified to net income	59	(9)	(141)
Tax effect	220	26	(61)
Total other comprehensive income	(668)	(79)	443
Ending balance	(298)	370	449
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	370	449	6
Ending balance	(298)	370	449
Net pension amortization and net actuarial loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(4,932)	(5,510)	(3,605)
Changes before reclassifications	1,539	428	(1,809)
Reclassification of certain income tax effects			(708)
Amounts reclassified to net income	306	347	218
Tax effect	(451)	(197)	394
Total other comprehensive income	1,394	578	(1,905)
Ending balance	(3,538)	(4,932)	(5,510)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	(4,932)	(5,510)	(3,605)
Ending balance	(3,538)	(4,932)	(5,510)
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,521)	(6,952)	(3,462)
Ending balance	(5,797)	(1,521)	(6,952)
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	(1,521)	(6,952)	(3,462)
Ending balance	(5,797)	(1,521)	(6,952)
Non-Controlling Interests
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	8,648	15,553	14,468
Ending balance	8,897	8,648	15,553
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance	8,648	15,553	14,468
Net income	2,311	1,068	1,515
Other comprehensive income (loss)	(802)	534	(266)
Dividends distributed to joint venture minority partners	(1,260)	(8,507)	0
Other changes in noncontrolling interests	0	0	(164)
Ending balance	$ 8,897	$ 8,648	$ 15,553