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Inventories (Summary of Inventories) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Inventory Disclosure [Abstract] |  |
NGLs | $ 9 | $ 4
Line fill | 9 | 8
Spare parts, materials and supplies | 59 | 53
Total inventories | $ 77 | $ 65

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- Definition Carrying amount as of the balance sheet date of natural gas or natural gas liquids in storage, which is ready for sale. + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of liquid hydrocarbon components recovered from natural gas. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Gross amount of components of assembled products that can be sold directly or indirectly through sales of assembled products. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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