Landfill and Environmental Costs (Expected Future Payments for Final Capping, Closure and Post-Closure) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Environmental Remediation Obligations [Abstract]
2019	$ 76.7
2020	89.0
2021	74.7
2022	68.3
2023	74.7
Thereafter	6,114.6
Total future payments for final capping, closure and post-closure	$ 6,498.0