CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash Flows From Operating Activities:
Net income	$ 476.4	$ 297.1	$ 1,063.9
Reconciling adjustments:
Depreciation and amortization	153.1	142.2	139.2
Amortization of operating lease right of use assets	133.7	142.0	153.0
Deferred income taxes	20.9	19.6	90.2
(Gain) Loss on disposal of property and equipment	(2.3)	0.6	(1.5)
Share-based compensation expense	26.5	23.8	18.3
Loss (Income) from SSAT	1.0	(2.2)	(83.1)
Distributions from SSAT	14.0		47.3
Other	(10.3)	(0.5)	2.1
Changes in assets and liabilities:
Accounts receivable, net	9.8	(10.9)	74.6
Deferred dry-docking payments	(30.2)	(24.1)	(25.7)
Deferred dry-docking amortization	27.2	25.3	24.9
Prepaid expenses and other assets	94.8	33.5	(45.2)
Accounts payable, accruals and other liabilities	(5.6)	10.9	(31.7)
Operating lease assets and liabilities, net	(139.5)	(144.8)	(154.1)
Other long-term liabilities	(1.7)	(2.0)	(0.3)
Net cash provided by operating activities	767.8	510.5	1,271.9
Cash Flows From Investing Activities:
Capitalized vessel construction expenditures	(95.6)	(52.9)	(62.4)
Capital expenditures (excluding vessel construction expenditures)	(214.5)	(195.5)	(146.9)
Proceeds from disposal of property and equipment, net	5.9	1.2	1.2
Payments for asset acquisitions	(0.8)	(12.4)	(3.0)
Cash and interest deposits into Capital Construction Fund	(120.7)	(128.5)	(582.8)
Withdrawals from Capital Construction Fund	89.6	49.9	64.6
Net cash used in investing activities	(336.1)	(338.2)	(729.3)
Cash Flows From Financing Activities:
Repayments of debt	(39.7)	(76.9)	(111.5)
Dividends paid	(44.8)	(45.0)	(48.0)
Repurchase of Matson common stock	(199.1)	(155.2)	(397.0)
Tax withholding related to net share settlements of restricted stock units	(17.6)	(12.6)	(20.1)
Net cash used in financing activities	(301.2)	(289.7)	(576.6)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	130.5	(117.4)	(34.0)
Cash, Cash Equivalents and Restricted Cash, Beginning of the Year	136.3	253.7	287.7
Cash, Cash Equivalents and Restricted Cash, End of the Year	266.8	136.3	253.7
Reconciliation of Cash, Cash Equivalents, and Restricted Cash, at End of the Year:
Cash and Cash Equivalents	266.8	134.0	249.8
Restricted Cash		2.3	3.9
Total Cash, Cash Equivalents and Restricted Cash, End of the Year	266.8	136.3	253.7
Supplemental Cash Flow Information:
Interest paid, net of capitalized interest	5.9	11.1	16.2
Income tax paid, net of income tax refunds	(26.5)	7.5	215.2
Non-cash Information:
Capital expenditures included in accounts payable, accruals and other liabilities	$ 7.9	10.8	5.5
Non-cash payments for intangible asset acquisitions		$ 2.7	$ 2.2