Business Acquisitions - Business Acquisition, Pro Forma Information (Details) - Questar Pipelines - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Business acquisition, pro forma adjustment, transaction costs		$ 48,700
Business acquisition, pro forma adjustment, transaction costs, incremental interest expense	$ 48,400	52,100
Total operating revenues	4,236	3,980
Net income (loss) attributable	$ 278	$ 276
Basic earnings per share (in USD per Share)	$ 4.70	$ 4.93
Diluted earnings per share (in USD per Share)	$ 4.69	$ 4.93

Business Acquisition, Pro Forma Adjustment, Incremental Interest Expense

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Business Acquisition, Pro Forma Adjustment, Transaction Costs

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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.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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