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SIGNIFICANT ACCOUNTING POLICIES - Landfill Accounting and Non-Landfill Closure and Post-Closure Liabilities (Details)
$ in Millions
12 Months Ended
Dec. 31, 2023
USD ($)
cubic_yard
landfill_site
Dec. 31, 2022
USD ($)
cubic_yard
Dec. 31, 2021
USD ($)
cubic_yard
Property, Plant and Equipment [Line Items]      
Landfill sites | landfill_site 8    
Permitted, but not highly probable airspace (cubic yards) 0 0  
Remaining Airspace Capacity [Roll Forward]      
Remaining capacity, beginning of period (cubic yards) 28,270,000 23,784,000  
Changes in highly probable airspace, net (cubic yards) 464,000 5,579,000  
Consumed (cubic yards) (981,000) (1,093,000)  
Remaining capacity, end of period (cubic yards) 27,753,000 28,270,000 23,784,000
Landfill final closure and post-closure liabilities | $ $ 59.4 $ 62.3  
Regulatory post-closure period for landfill (in years) 30 years    
Asset retirement obligations, risk free rate (as a percent) 6.51% 5.37%  
Non-landfill closure and post-closure liabilities | $ $ 59.2 $ 56.6  
Minimum      
Remaining Airspace Capacity [Roll Forward]      
Non-landfill closure and post-closure liabilities, period (in years) 10 years    
Maximum      
Remaining Airspace Capacity [Roll Forward]      
Non-landfill closure and post-closure liabilities, period (in years) 30 years    
Buttonwillow | California      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 20 years    
Deer Trail | Colorado      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 21 years    
Grassy Mountain | Utah      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 34 years    
Kimball | Nebraska      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 23 years    
Lambton | Ontario, Canada      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 46 years    
Lone Mountain | Oklahoma      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 16 years    
Ryley | Alberta, Canada      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 30 years    
Sawyer | North Dakota      
Property, Plant and Equipment [Line Items]      
Remaining Lives (Years) 65 years    
Landfill assets      
Property, Plant and Equipment [Line Items]      
Amortization | $ $ 18.6 $ 16.2 $ 13.7
Permitted      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 27,753,000    
Permitted | Buttonwillow | California      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 4,999,000    
Permitted | Deer Trail | Colorado      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 1,420,000    
Permitted | Grassy Mountain | Utah      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 4,320,000    
Permitted | Kimball | Nebraska      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 547,000    
Permitted | Lambton | Ontario, Canada      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 4,350,000    
Permitted | Lone Mountain | Oklahoma      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 3,165,000    
Permitted | Ryley | Alberta, Canada      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 5,692,000    
Permitted | Sawyer | North Dakota      
Property, Plant and Equipment [Line Items]      
Remaining highly probable airspace 3,260,000