Contingencies and commitments.

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25336-109308

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount purchased during the period under an unrecorded unconditional purchase obligation (for example, under the take-or-pay or throughput contract).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25336-109308

+ Details

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

- Details

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- Details

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Contingencies and Commitments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Contingencies and Commitments (Textual) [Abstract]
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2017	$ 319
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2018	319
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2019	319
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2020	319
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2021	319
Aggregate amounts of estimated payments under long-term throughput and take-or-pay agreements - 2022 and after	2,902
Total payments under long-term throughput and take-or-pay agreements	325	$ 328	$ 331
Revolving Credit Facility
Contingencies and Commitments (Textual) [Abstract]
Performance obligations secured by letters of credit and bank guarantees	51
Performance Guarantee
Contingencies and Commitments (Textual) [Abstract]
Performance obligations secured by letters of credit and bank guarantees	541
Performance Guarantee \| Revolving Credit Facility
Contingencies and Commitments (Textual) [Abstract]
Performance obligations secured by letters of credit and bank guarantees	$ 51