Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
OPERATING ACTIVITIES
Net income	$ 63,141,000	$ 71,199,000	$ 58,723,000
Adjustments to reconcile net income to net cash and cash equivalents provided by operating activities:
Depreciation and amortization	45,004,000	18,682,000	16,456,000
Net loss on disposal of property, plant and equipment	615,000	444,000	1,576,000
Gain on sales of assets held for sale	257,000	0	0
Stock-based compensation expense	3,097,000	3,469,000	3,609,000
Deferred income taxes	21,404,000	9,899,000	11,629,000
Pension contributions in excess of expense	(20,928,000)	(27,840,000)	(4,732,000)
Excess tax benefit from stock-based compensation	0	0	(4,968,000)
Contributions of employer stock to employee benefit plan	3,554,000	2,926,000	1,761,000
Other non-cash items	14,000	318,000	(663,000)
Changes in operating assets and liabilities:
Customer receivables	(18,786,000)	(7,780,000)	(9,938,000)
Inventories	2,802,000	(4,925,000)	(4,276,000)
Income taxes receivable	(7,295,000)	0	0
Prepaid expenses and other assets	(7,492,000)	(207,000)	(4,585,000)
Accounts payable	(858,000)	6,301,000	723,000
Accrued compensation and related expenses	(2,525,000)	773,000	5,269,000
Income taxes payable	0	0	(1,791,000)
Marketing and other accrued expenses	4,771,000	3,821,000	5,811,000
Net Cash Provided by Operating Activities	86,775,000	77,080,000	74,604,000
INVESTING ACTIVITIES
Payments to acquire property, plant, and equipment	(47,590,000)	(21,811,000)	(28,685,000)
Proceeds from sales of property, plant, and equipment	27,000	37,000	846,000
Proceeds from sales of assets held for sale	(57,200,000)	0	0
Purchases of certificates of deposit	(25,000,000)	(85,000,000)	(46,750,000)
Proceeds from Maturities, Prepayments and Calls of Short-term Investments	87,750,000	56,750,000	38,250,000
Investment in promotional displays	(2,303,000)	(3,720,000)	(4,434,000)
Net Cash Used by Investing Activities	(44,316,000)	(53,744,000)	(40,773,000)
FINANCING ACTIVITIES
Payments of long-term debt	(96,572,000)	(11,731,000)	(1,547,000)
Proceeds from long-term debt	734,000	3,477,000	3,196,000
Excess tax benefit from stock-based compensation	0	0	4,968,000
Proceeds from issuance of common stock and other	1,289,000	2,366,000	8,114,000
Repurchase of common stock	(29,000,000)	(13,407,000)	(16,593,000)
Withholding of employee taxes related to stock-based compensation	(2,803,000)	(1,734,000)	(2,826,000)
Debt issuance cost	(14,675,000)	0	0
Notes receivable, net	0	208,000	(4,221,000)
Net Cash Provided (Used) by Financing Activities	(141,027,000)	(20,821,000)	(8,909,000)
Net Increase in Cash And Cash Equivalents	(98,568,000)	2,515,000	24,922,000
Cash And Cash Equivalents, Beginning of Year	176,978,000	174,463,000	149,541,000
Cash And Cash Equivalents, End of Year	78,410,000	176,978,000	174,463,000
Non-cash investing and financing activities:
Long-term debt related to funding acquisition	300,000	0	0
Long-term debt issued to satisfy outstanding debt	600,000	0	0
Long-term debt satisfied from issuance of debt	(602,750)	0	0
Stock issuance in connection with acquisition	189,849	0	0
Property, plant and equipment	5,530	0	0
Net other assets and liabilities related to acquisition	7,169	0	0
Cash paid during the period for:
Interest	5,919	596	776
Income taxes	$ 18,219	$ 27,302	$ 24,510