Revenue - Schedule of Utilities Operating Revenue Expense Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Utility-related taxes	$ 59,319	$ 59,528	$ 58,730

Public Utility Operating Expenses Excise Taxes Collected and Reported Gross in Revenues and Operating Expenses

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration