CAPITAL CONSTRUCTION FUND - Summary of the activities within the CCF Assigned Accounts Receivable account (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2024
CAPITAL CONSTRUCTION FUND
Cash and cash equivalents, and investments account	$ 599.4	$ 642.6
Assigned accounts receivables	$ 200.0

The carrying value of cash and cash equivalents and investments in capital construction fund.

No definition available.

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