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Acquisitions (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
Acquisitions (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Feb. 11, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Business Acquisition [Line Items]
Goodwill			$ 410,777		$ 410,777		$ 323,189
Selling, general, and administrative expense			48,329	$ 42,506	89,527	$ 84,501
Net sales			309,517	273,624	555,874	514,634
Total consolidated income from operations			39,506	$ 40,822	68,161	$ 70,914
Lane Supply
Business Acquisition [Line Items]
Acquisition purchase price		$ 118,000
Goodwill		$ 38,300
Net sales					65,300
Two Privately Held Businesses
Business Acquisition [Line Items]
Acquisition purchase price	$ 90,200
Two Metal Roofing Businesses
Business Acquisition [Line Items]
Goodwill			48,327		48,327
2025 Acquisitions
Business Acquisition [Line Items]
Selling, general, and administrative expense			$ 500		$ 3,100