Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 35
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=124268079&loc=d3e32787-111569

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

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Equity Investments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Other-than-temporary impairment expense	$ 11,805	$ 29,399
Equity-investment balance	1,167,187	1,224,813		$ 1,285,717
White Cliffs [Member]
Schedule of Equity Method Investments [Line Items]
Equity investment difference between carrying and underlying value	(4,600)
Other-than-temporary impairment expense	0	0
Equity-investment balance	$ 40,753	45,623		45,877
White Cliffs [Member] \| Related Parties [Member]
Schedule of Equity Method Investments [Line Items]
Equity-investment ownership percentage	0.40%
Rendezvous [Member]
Schedule of Equity Method Investments [Line Items]
Equity investment difference between carrying and underlying value	$ 27,200
Other-than-temporary impairment expense	0	0
Equity-investment balance	22,075	28,198		32,964
Whitethorn LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity investment difference between carrying and underlying value	(35,100)
Other-than-temporary impairment expense	0	0
Equity-investment balance	149,690	156,729		161,665
Saddlehorn [Member]
Schedule of Equity Method Investments [Line Items]
Equity investment difference between carrying and underlying value	(18,700)
Other-than-temporary impairment expense	0	0
Equity-investment balance	110,441	111,717		112,855
Ranch Westex [Member]
Schedule of Equity Method Investments [Line Items]
Equity investment difference between carrying and underlying value	(36,100)
Other-than-temporary impairment expense	11,805	29,399
Equity-investment balance	$ 979	$ 18,898	$ 2,900	$ 46,678