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Acquisitions and Investments - Marine Investments (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended | 16 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
May 31, 2016 USD ($) | Mar. 31, 2017 Joint_venture vessel | Dec. 31, 2016 vessel | Dec. 31, 2015 vessel | Dec. 31, 2016 USD ($) vessel | May 01, 2016 | Sep. 30, 2015
Crowley Coastal Partners |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Cash paid to acquire equity method investments | $ | $ 48 |  |  |  | $ 189 |  |
Equity method investments, ownership percentage |  | 50.00% |  |  |  |  |
Crowley Ocean Partners |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Cash paid to acquire equity method investments | $ |  |  |  |  | $ 141 |  |
Equity method investments, ownership percentage |  | 50.00% |  |  |  | 50.00% | 50.00%
Number of vessels | vessel |  |  | 2 | 2 | 4 |  |
Crowley Blue Water Partners |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Equity method investments, ownership percentage |  | 50.00% |  |  |  |  |
Number of vessels | vessel |  | 3 |  |  |  |  |
Crowley Maritime Corporation |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Number of joint ventures | Joint_venture |  | 2 |  |  |  |  |
Crowley Maritime Corporation | Crowley Blue Water Partners |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |
Percentage of partners interest contributed | 100.00% |  |  |  |  |  |

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