Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Disaggregation of Revenue [Line Items]
Net Sales	$ 1,650,333	$ 1,645,319	$ 1,250,274
Home center retailers
Disaggregation of Revenue [Line Items]
Net Sales	768,043	788,803	493,904
Builders
Disaggregation of Revenue [Line Items]
Net Sales	668,765	631,474	557,382
Independent dealers and distributors
Disaggregation of Revenue [Line Items]
Net Sales	$ 213,525	$ 225,042	$ 198,988

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration