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GOODWILL AND INTANGIBLE ASSETS - Summary of Goodwill Activity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,002,266
Acquisitions	111,959
Business Combination Adjustments	1,637
Goodwill, ending balance	1,115,862
Eastern
Goodwill [Roll Forward]
Goodwill, beginning balance	89,544
Acquisitions	20,989
Business Combination Adjustments	0
Goodwill, ending balance	110,533
Western
Goodwill [Roll Forward]
Goodwill, beginning balance	357,143
Acquisitions	6,983
Business Combination Adjustments	2,455
Goodwill, ending balance	366,581
Mid-Atlantic
Goodwill [Roll Forward]
Goodwill, beginning balance	510,917
Acquisitions	74,297
Business Combination Adjustments	(818)
Goodwill, ending balance	584,396
Resource Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance	44,662
Acquisitions	9,690
Business Combination Adjustments	0
Goodwill, ending balance	$ 54,352

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