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DESCRIPTION OF THE BUSINESS (Details) | 6 Months Ended | 9 Months Ended
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Jun. 30, 2021 segment | Jun. 30, 2020 segment | Sep. 30, 2021 segment facility
DESCRIPTION OF THE BUSINESS |  |  |
Number of reportable segments | segment | 2 | 2 | 2
Ocean Transportation | SSAT |  |  |
DESCRIPTION OF THE BUSINESS |  |  |
Ownership interest in SSAT (as a percent) |  |  | 35.00%
Number of terminal facilities on which SSAT provided terminal and stevedoring services on the U.S. West Coast |  |  | 7
MatNav | SSAT |  |  |
DESCRIPTION OF THE BUSINESS |  |  |
Number of terminal facilities on which SSAT provided terminal and stevedoring services on the U.S. West Coast |  |  | 3

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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8672-108599 + Details
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