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Commitments and Contingencies - Narrative (Details) | Sep. 20, 2018 subclass | Jan. 31, 2021 USD ($)
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Loss Contingencies [Line Items] |  |
Standby letters of credit |  | $ 151,000,000.0
Surety bonds |  | 640,600,000
Energy Savings Contracts |  |
Loss Contingencies [Line Items] |  |
Guarantee obligation |  | 173,800,000
Minimum |  |
Loss Contingencies [Line Items] |  |
Amount of reasonably possible loss |  | 0
Maximum |  |
Loss Contingencies [Line Items] |  |
Amount of reasonably possible loss |  | 5,000,000
Bucio |  |
Loss Contingencies [Line Items] |  |
Loss contingency, number of certified subclasses | subclass | 4 |
Pending Litigation |  |
Loss Contingencies [Line Items] |  |
Loss contingency amount accrued for probable losses |  | $ 13,800,000

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