MGP, Landfill and Disposal Sites (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Maximum [Member] \| Denver MGP Site [Member]
Site Contingency [Line Items]
Future environmental investigation, remediation or mitigation	$ 9.3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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