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Related Party Transactions - Purchases from Related Parties (Detail) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Related Party Transaction [Line Items] |  |
Purchases from related parties | $ 141 | $ 122
Crowley Blue Water Partners |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 16 | 14
Crowley Ocean Partners |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 20 | 19
Illinois Extension Pipeline |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 24 | 25
LOCAP |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 4 | 5
LOOP |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 17 | 13
TAAE |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 19 | 8
TACE |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 8 | 16
TAME |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | 20 | 17
Other equity method investees |  |
Related Party Transaction [Line Items] |  |
Purchases from related parties | $ 13 | $ 5

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