Property, Plant and Equipment (Net Changes in Capitalized Exploratory Well Costs) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Movement in Property, Plant and Equipment [Roll Forward]
Beginning balance	$ 179,481	$ 181,616
Additions pending the determination of proved reserves	9,412	15,921
Capitalized exploratory well costs charged to expense	(10,472)	0
Ending balance	$ 178,421	$ 197,537

Additions to capitalized exploratory well costs that were added during the reporting period pending the determination of proved reserves.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=126939881&loc=SL6806780-109447

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

- Definition

Amount of expense for capitalized exploratory well costs for which proved reserves were not found at the exploratory well.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(3)
-URI https://asc.fasb.org/extlink&oid=126939881&loc=SL6806780-109447

+ Details

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Period Type:	duration

- Definition

The amount of capitalized exploratory well costs that is pending the determination of proved reserves. This does not include amounts that were capitalized and subsequently expensed in the same annual period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126939881&loc=SL6806780-109447

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Balance Type:	na
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