Segment Information - Narrative (Detail)	9 Months Ended
Jan. 31, 2021 Segment
Segment Reporting [Abstract]
Number of operating segments	2
Description of changes in reporting goodwill and intangible assets in segment assets	Goodwill and intangible assets are not included in segment assets as these assets are not used by the Chief Operating Decision Maker to evaluate the respective segment’s operating performance, allocate resources to individual segments, or determine executive compensation.

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration