CAPITAL CONSTRUCTION FUND (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
CAPITAL CONSTRUCTION FUND
CCF on deposit	$ 27.5	$ 27.5
Eligible accounts receivable assigned to CCF	150.9	150.7
Total	178.4us-gaap_OtherAssets	178.2us-gaap_OtherAssets
Cash Deposits Into CCF	$ 27.5	$ 27.5

The amount of accrued deposits from certain qualified earnings to the Capital Construction Fund that are reflected as obligations on the consolidated balance sheets.

No definition available.

+ Details

Name:	matx_AccruedDepositsToCapitalConstructionFund
Namespace Prefix:	matx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	matx_CapitalConstructionFundAbstract
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Balance Type:	na
Period Type:	duration

- Definition

The cash outflow from making deposits into the capital construction fund to be used for qualified purchases under provisions of Merchant Marine Act, 1936, as amended.

+ References

No definition available.

+ Details

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Namespace Prefix:	matx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net balance of amount accrued for withdrawal and deposits to the Capital Construction Fund, reflected in the consolidated balance sheets.

+ References

No definition available.

+ Details

Name:	matx_NetBalanceOfAmountsAccruedForCapitalConstructionFund
Namespace Prefix:	matx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 7

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant