v2.4.0.8

Business Combinations Business Combinations (Narrative) (Details) (USD $) | 9 Months Ended |  |  |  |  | 1 Months Ended
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Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2013 | Sep. 30, 2014 Senior Notes [Member] 5.15% Notes Due 2043 [Member] | Dec. 31, 2013 Senior Notes [Member] 5.15% Notes Due 2043 [Member] | Nov. 30, 2013 Senior Notes [Member] 5.15% Notes Due 2043 [Member] Debt Offering Part One [Member] | Jul. 31, 2013 Plains Pipeline Acquisition [Member] New Mexico System [Member] mi | Nov. 30, 2013 Plains Pipeline Acquisition [Member] Rocky Mountains [Member] Terminal mi bbl
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Pipeline Length |  |  |  |  |  |  | 250 | 550
Payments to Acquire Businesses, Net of Cash Acquired | $ 0 | $ 57,000,000 |  |  |  |  | $ 57,000,000 | $ 135,000,000
Number of Pipeline Terminals |  |  |  |  |  |  |  | 4
Storage Capacity |  |  |  |  |  |  |  | 1,700,000
Debt Instrument, Face Amount | $ 3,000,000,000.0 |  | $ 2,700,000,000.0 | $ 550,000,000.0 | $ 300,000,000.0 | $ 300,000,000.0 |  |

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