Commitments And Contingencies [Line Items]

No definition available.

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- Definition

Liability Associated With Indemnification Obligation

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Number Of Cases Removed To Federal Court

+ References

No definition available.

+ Details

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- Definition

Number Of State Cases Set For Trial

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No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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Balance Type:	debit
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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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Commitments And Contingencies (Narrative) (Details)	1 Months Ended	3 Months Ended
Commitments And Contingencies (Narrative) (Details)	Sep. 30, 2015 plaintiff item	Mar. 31, 2017 USD ($) item
Commitments And Contingencies [Line Items]
Obligation under transportation agreements \| $		$ 8,672,000,000
Guarantee obligations relative to the firms transportation agreements and gathering project and services \| $		$ 821,000,000
Number of state cases set for trial		1
Indemnification liability \| $		$ 0
Arkansas Royalty Litigation [Member]
Commitments And Contingencies [Line Items]
Number of cases		3
Arkansas Royalty Litigation [Member] \| Arkansas State Court 2010 and 2013 [Member]
Commitments And Contingencies [Line Items]
Number of cases		2
Arkansas Royalty Litigation [Member] \| Federal Court 2014 [Member]
Commitments And Contingencies [Line Items]
Number of cases		1
Arkansas Royalty Litigation [Member] \| Arkansas State Court 2015 [Member]
Commitments And Contingencies [Line Items]
Number of cases	3
Number of plaintiffs \| plaintiff	248
Arkansas Royalty Litigation [Member] \| Federal Court [Member]
Commitments And Contingencies [Line Items]
Number of cases removed to federal court	2
Minimum [Member] \| Arkansas Royalty Litigation [Member] \| Federal Court 2014 [Member]
Commitments And Contingencies [Line Items]
Loss contingency, range of possible loss, minimum \| $		$ 98,000,000
Pending Regulatory Approval and/or Construction [Member]
Commitments And Contingencies [Line Items]
Obligation under transportation agreements \| $		$ 3,661,000,000