SIGNIFICANT ACCOUNTING POLICIES - RECOGNITION OF REVENUES AND EXPENSES (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Total	$ 513.9	$ 532.4
Ocean Transportation
Ocean Transportation services	391.1	387.9
Terminal and other related services	5.8	6.7
Fuel sales	2.6	2.0
Vessel management services and related costs	$ 1.4	$ 1.3
Percentage of ocean transportation revenues and fuel sales denominated in foreign currency	3.00%	3.00%
Total	$ 400.9	$ 397.9
Logistics
Transportation Brokerage and Freight Forwarding Services	102.1	123.3
Warehouse and distribution services	8.2	8.4
Supply chain management and other services	2.7	2.8
Total	$ 113.0	$ 134.5
Percentage of transportation brokerage and freight forwarding services revenue denominated in foreign currency	3.00%	3.00%
Ocean Transportation
Total	$ 400.9	$ 397.9
Logistics
Total	$ 113.0	134.5
Reclassify Transportation Brokerage and Freight Forwarding Services
Transportation Brokerage and Freight Forwarding Services		(3.1)
Warehouse and distribution services		$ 3.1

Amount of fuel sales revenue.

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- Definition

Amount of ocean transportation services revenue.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of ship management services revenue and related costs.

+ References

No definition available.

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- Definition

Amount of supply chain management and other services revenue

+ References

No definition available.

+ Details

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- Definition

Amount of terminal and other related services revenue.

+ References

No definition available.

+ Details

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- Definition

Amount of transportation brokerage and freight forwarding services revenue.

+ References

No definition available.

+ Details

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- Definition

Amount of warehouse and distribution services revenue.

+ References

No definition available.

+ Details

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- Definition

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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