Business Combinations - Assets Acquired and Liabilities Assumed Westside Building Material (Details) - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
Apr. 30, 2022	Apr. 30, 2022	Jul. 01, 2021	Apr. 30, 2021
Business Acquisition [Line Items]
Goodwill	$ 695,897	$ 695,897		$ 576,330
Adjustments, Goodwill		476
Westside Building Material
Business Acquisition [Line Items]
Trade accounts and notes receivable	26,282	26,282	$ 27,081
Adjustments, Trade accounts and notes receivable	(799)
Inventories	28,755	28,755	28,900
Adjustments, Inventories	(145)
Prepaid and other current assets	228	228	228
Property and equipment	16,687	16,687	16,687
Operating lease right-of-use assets	20,782	20,782	20,782
Goodwill	14,714	14,714	13,351
Adjustments, Goodwill	1,363
Accounts payable and accrued expenses	(14,321)	(14,321)	(14,375)
Adjustments, Accounts payable and accrued expenses	54
Operating lease liabilities	(15,819)	(15,819)	(15,819)
Fair value of consideration transferred	140,108	140,108	139,635
Adjustments, Fair value of consideration transferred	473
Westside Building Material \| Customer relationships
Business Acquisition [Line Items]
Intangible assets	51,500	51,500	51,500
Westside Building Material \| Tradenames
Business Acquisition [Line Items]
Intangible assets	$ 11,300	$ 11,300	$ 11,300

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current Assets, Receivables

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Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current Liabilities, Accounts Payable

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating Lease, Right-of-Use Assets

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Amount of lease obligation assumed in business combination.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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