Expected payment date of bankruptcy claim settled.

No definition available.

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- Definition

Claim reserve account established after the effective date.

+ References

No definition available.

+ Details

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- Definition

Rate paid for daily production of the applicable energy source.

+ References

No definition available.

+ Details

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- Definition

Date when commitment starts

+ References

No definition available.

+ Details

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- Definition

Annual purchase commitment amount

+ References

No definition available.

+ Details

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- Definition

Daily production of the applicable energy source to flow through REX.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Period covered by contractural commitment for firm transportation capacity.

+ References

No definition available.

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- Definition

Amount of bankruptcy claim filed with bankruptcy court.

+ References

No definition available.

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- Definition

Amount of bankruptcy claim settled.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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Commitments and Contingencies (Narratives) (Details)						1 Months Ended
Commitments and Contingencies (Narratives) (Details)	Apr. 12, 2017 USD ($)	Apr. 10, 2017 USD ($)	Mar. 02, 2017 USD ($) Dekatherms / d $ / Dekatherms	Apr. 04, 2016 USD ($)	Mar. 08, 2016 MMBTU / d	Oct. 27, 2017 USD ($)	Jan. 20, 2017	Dec. 29, 2016 USD ($)	Aug. 31, 2016 USD ($)	Aug. 30, 2016 USD ($)	Aug. 26, 2016 USD ($)	Aug. 25, 2016 USD ($)	Apr. 29, 2016 USD ($)	Apr. 14, 2017 USD ($)
Rockie Express Pipeline \| Sempra
Contingencies
Bankruptcy Claims Amount Of Claims Filed												$ 63,800,000
Transportation Commitment Capacity \| MMBTU / d					50,000
Rockie Express Pipeline \| REX
Contingencies
Damage sought				$ 303,200,000
Bankruptcy Claims Amount Of Claims Filed											$ 303,300,000
Cash payment for legal settlement			$ 150,000,000
Transportation Commitment Capacity Term			7 years
Transportation Commitment Capacity \| Dekatherms / d			200,000
Commitment start date			Dec. 01, 2019
Annual purchase commitment amount			$ 26,800,000
Commitment Capacity Rate \| $ / Dekatherms			0.37
Royalties \| ONRR
Contingencies
Bankruptcy Claims Amount Of Claims Filed						$ 35,100,000
Oil Sales Contract \| SPMT
Contingencies
Damage sought													$ 38,600,000
Bankruptcy Claims Amount Of Claims Filed									$ 16,900,000
Oil Sales Contract \| Big West
Contingencies
Bankruptcy Claims Amount Of Claims Filed										$ 32,600,000
Transportation Commitment Capacity Term							2 years
Indebtedness Claims \| Notes holders \| Minimum
Contingencies
Damage sought								$ 200,725,869
Subsequent event \| Rockie Express Pipeline \| Sempra
Contingencies
Claims settled		$ 57,000,000
Payment date		May 27, 2017
Subsequent event \| Oil Sales Contract \| Big West
Contingencies
Cash payment for legal settlement	$ 17,350,000
Subsequent event \| Indebtedness Claims \| Notes holders
Contingencies
Claim reserve account after effective date														$ 400,000,000