CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Other comprehensive income (loss):
Unamortized retirement costs, tax (expense) benefit	$ 5,967	$ (13,440)	$ (2,103)
Unrealized gain (loss) on interest rate swaps, tax (expense) benefit	$ (393)	$ (2,787)	$ (657)

Amount, before adjustments, of tax expense (benefit) for gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480627/815-20-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (dd)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
-Subparagraph (bb)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C

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Balance Type:	debit
Period Type:	duration