Segment Information - Accounts Receivable for Services (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Centuri
Segment Reporting Information [Line Items]
Centuri accounts receivable for services provided to Southwest	$ 15,376	$ 13,956

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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+ Details