No definition available.

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- Definition

The contribution, under the defined contribution plan, made by the employer as a percentage when a minimum threshold of the entity's performance is achieved.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of the profit sharing expenses recorded during the period for defined contribution plans.

+ References

No definition available.

+ Details

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

- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Details

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- Details

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PENSION AND POST-RETIREMENT PLANS - DEFINED CONTRIBUTION PLANS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
401(K) plan
Defined Contribution Plans
Employer matching contribution (as a percent)	6.00%
Employer matching contribution expenses	$ 2.0	$ 1.6	$ 1.6
Profit sharing plan
Defined Contribution Plans
Profit sharing expense recorded	$ 1.9	$ 1.6	$ 1.2
Profit sharing plan \| Maximum
Defined Contribution Plans
Contribution percentage	3.00%