Segments - Net Sales, Adjusted EBITDA and Certain Other Measures (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Apr. 30, 2020
Segment information
Net sales	$ 802,573	$ 847,176
Gross Profit	260,458	273,654
Depreciation and Amortization	27,097	29,275
Adjusted EBITDA	83,054	83,588
Total assets	2,225,830		$ 2,288,782
Geographic divisions
Segment information
Net sales	794,472	840,157
Gross Profit	257,838	271,354
Depreciation and Amortization	26,782	28,934
Adjusted EBITDA	82,503	83,082
Other.
Segment information
Net sales	8,101	7,019
Gross Profit	2,620	2,300
Depreciation and Amortization	91	52
Adjusted EBITDA	551	506
Corporate
Segment information
Depreciation and Amortization	$ 224	$ 289