Segment and Related Information - Disaggregated Revenue (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Service revenues	$ 400.4	$ 419.5	$ 419.1	$ 384.0	$ 394.8	$ 400.6	$ 398.1	$ 364.7	$ 1,623.0	$ 1,558.2	$ 1,507.6
Residential Collection Revenue
Disaggregation of Revenue [Line Items]
Service revenues									410.9	402.9
Commercial Collection Revenue
Disaggregation of Revenue [Line Items]
Service revenues									396.5	376.3
Rolloff Collection Revenue
Disaggregation of Revenue [Line Items]
Service revenues									266.2	256.6
Disposal Revenue
Disaggregation of Revenue [Line Items]
Service revenues									283.9	271.2
Fuel and Environmental Charges
Disaggregation of Revenue [Line Items]
Service revenues									112.1	115.5
Sale of Recyclables
Disaggregation of Revenue [Line Items]
Service revenues									8.1	16.9
Other Revenue (1)
Disaggregation of Revenue [Line Items]
Service revenues									$ 145.3	$ 118.8