Commitments and Contingencies - Legal Matters (Details) - 2020 Wildfires - PAC naturalGasProducer in Thousands, a in Thousands, $ in Millions	1 Months Ended
Sep. 30, 2020 USD ($) a naturalGasProducer	Sep. 30, 2021 USD ($)
Loss Contingencies [Line Items]
Number of acres burned \| a	500
Number of structures destroyed \| naturalGasProducer	2
Fire suppression costs	$ 150
Estimate of possible loss		$ 136

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant