Fair Value Measurements (Fair Value Of Assets On Recurring Basis) (Details) - USD ($) $ in Thousands	Jul. 31, 2021	Apr. 30, 2021
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	$ 503
Interest Rate Cash Flow Hedge Liability at Fair Value	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	350
Interest Rate Cash Flow Hedge Liability at Fair Value	573
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	0
Interest Rate Cash Flow Hedge Liability at Fair Value	0
Foreign exchange forward contracts | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	0
Foreign exchange forward contracts | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	350
Foreign exchange forward contracts | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	0
Mutual funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, at fair value	503	$ 642
Mutual funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, at fair value	0	0
Mutual funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, at fair value	$ 0	$ 0