SIGNIFICANT ACCOUNTING POLICIES - RECOGNITION OF REVENUES AND EXPENSES (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Total	$ 532.4	$ 511.4
Ocean Transportation
Ocean Transportation services	387.9	368.8
Terminal and other related services	6.7	6.2
Fuel sales	2.0	2.6
Vessel management services and related costs	$ 1.3	$ 1.7
Percentage of ocean transportation revenues and fuel sales denominated in foreign currency	3.00%	3.00%
Total	$ 397.9	$ 379.3
Logistics
Transportation Brokerage and Freight Forwarding Services	126.4	124.5
Warehouse and distribution services	5.3	4.6
Supply chain management and other services	2.8	3.0
Total	$ 134.5	$ 132.1
Percentage of transportation brokerage and freight forwarding services revenue denominated in foreign currency	3.00%	3.00%
Ocean Transportation
Total	$ 397.9	$ 379.3
Logistics
Total	$ 134.5	$ 132.1

Amount of fuel sales revenue.

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Amount of ocean transportation services revenue.

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Percentage of ocean transportation revenues and fuel sales denominated in foreign currency.

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No definition available.

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Percentage of transportation brokerage and freight forwarding services revenue denominated in foreign currency.

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No definition available.

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- Definition

Amount of ship management services revenue and related costs.

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No definition available.

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Amount of supply chain management and other services revenue

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No definition available.

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Amount of terminal and other related services revenue.

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No definition available.

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- Definition

Amount of transportation brokerage and freight forwarding services revenue.

+ References

No definition available.

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Amount of warehouse and distribution services revenue.

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No definition available.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 32
-Paragraph 2A
-URI http://asc.fasb.org/extlink&oid=82859839&loc=SL82860478-203043

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130543-203045

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130539-203045

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130545-203045

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