Risk Management Risk Management Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions		12 Months Ended
Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive loss, beginning of period	$ (541)	$ (541)	$ (661)	$ (461)
OCI, before Reclassifications, Net of Tax, Attributable to Parent		(9)	240	(84)
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent		329	(171)	(116)
Other Comprehensive Income, KML IPO			51
Impact of adoption of ASU 2018-02	66	(109)
Net current-period other comprehensive (loss) income		211	120	(200)
Accumulated other comprehensive loss, end of period		(330)	(541)	(661)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax, begiining of period	(27)	(27)	(1)	219
OCI, before Reclassifications, Net of Tax, Attributable to Parent		111	145	(104)
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent		84	(171)	(116)
Other Comprehensive Income, KML IPO			0
Impact of adoption of ASU 2018-02		(4)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent		191	(26)	(220)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax, end of period		164	(27)	(1)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, beginning of period	(189)	(189)	(288)	(322)
OCI, before Reclassifications, Net of Tax, Attributable to Parent		(89)	55	34
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent		223	0	0
Other Comprehensive Income, KML IPO			44
Impact of adoption of ASU 2018-02		(36)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent		98	99	34
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, end of period		(91)	(189)	(288)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, beginning of period	$ (325)	(325)	(372)	(358)
OCI, before Reclassifications, Net of Tax, Attributable to Parent		(31)	40	(14)
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent		22	0	0
Other Comprehensive Income, KML IPO			7
Impact of adoption of ASU 2018-02		(69)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent		(78)	47	(14)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, end of period		$ (403)	$ (325)	$ (372)

Other Comprehensive Income, KML IPO

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Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income [Roll Forward]

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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