Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015
OPERATING ACTIVITIES
Net income	$ 71,199	$ 58,723	$ 35,499
Adjustments to reconcile net income to net cash and cash equivalents provided by operating activities:
Depreciation and amortization	18,682	16,456	14,526
Net loss on disposal of property, plant and equipment	444	1,576	153
Gain on sales of assets held for sale	0	0	(250)
Stock-based compensation expense	3,469	3,609	3,497
Deferred income taxes	9,899	11,629	4,335
Pension contributions in excess of expense	(27,840)	(4,732)	(4,604)
Excess tax benefit from stock-based compensation	0	(4,968)	(1,887)
Contributions of employer stock to employee benefit plan	2,926	1,761	6,217
Other non-cash items	318	(663)	216
Changes in operating assets and liabilities:
Customer receivables	(7,780)	(9,938)	288
Inventories	(4,925)	(4,276)	(5,605)
Prepaid expenses and other assets	(207)	(4,585)	126
Accounts payable	6,301	723	5,113
Accrued compensation and related expenses	773	5,269	1,963
Income taxes payable	0	(1,791)	1,201
Marketing and other accrued expenses	3,821	5,811	(624)
Net Cash Provided by Operating Activities	77,080	74,604	60,164
INVESTING ACTIVITIES
Payments to acquire property, plant, and equipment	(21,811)	(28,685)	(20,015)
Proceeds from sales of property, plant, and equipment	37	846	22
Proceeds from sales of assets held for sale	0	0	1,250
Purchases of certificates of deposit	(85,000)	(46,750)	(40,750)
Proceeds from Maturities, Prepayments and Calls of Short-term Investments	56,750	38,250	5,250
Investment in promotional displays	(3,720)	(4,434)	(2,363)
Net Cash Used by Investing Activities	(53,744)	(40,773)	(56,606)
FINANCING ACTIVITIES
Payments of long-term debt	(11,731)	(1,547)	(1,309)
Proceeds from long-term debt	3,477	3,196	1,500
Excess tax benefit from stock-based compensation	0	4,968	1,887
Proceeds from issuance of common stock and other	2,366	8,114	14,268
Repurchase of common stock	(13,407)	(16,593)	(5,053)
Withholding of employee taxes related to stock-based compensation	(1,734)	(2,826)	(1,427)
Notes receivable, net	208	(4,221)	417
Net Cash Provided (Used) by Financing Activities	(20,821)	(8,909)	10,283
Net Increase in Cash And Cash Equivalents	2,515	24,922	13,841
Cash And Cash Equivalents, Beginning of Year	174,463	149,541	135,700
Cash And Cash Equivalents, End of Year	$ 176,978	$ 174,463	$ 149,541