Commitments and Contingencies - Construction Commitments and Easements (Details) - MEC $ in Millions	Sep. 30, 2021 USD ($)
Construction Commitment
Loss Contingencies [Line Items]
Purchase obligation	$ 405
Easements
Loss Contingencies [Line Items]
Purchase obligation	$ 87

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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