PARENT-ONLY FINANCIAL STATEMENTS - Cash Flow Statement (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating activities
Net income attributable to Huntington		$ 2,211	$ 1,940	$ 1,951
Adjustments to reconcile net income to net cash provided by operating activities:
Other, net		(71)	1	30
Net cash provided by operating activities		2,482	1,836	2,657
Investing activities
Net cash received from business combinations		864	0	0
Other, net		81	87	88
Net cash used in investing activities		(6,347)	(12,119)	(2,997)
Financing activities
Net proceeds from issuance of long-term debt		2,500	7,661	14,965
Repayment of long-term debt		(2,053)	(3,563)	(12,376)
Net proceeds from issuance of preferred stock		741	0	317
Repurchase/redemption of preferred stock		0	(410)	(82)
Other, net		(90)	(56)	(46)
Net cash provided by financing activities		4,513	13,001	3,765
Increase in cash and cash equivalents		648	2,718	3,425
Cash and cash equivalents at beginning of period	[1]	12,847	10,129	6,704
Cash and cash equivalents at end of period	[1]	13,495	12,847	10,129
Supplemental disclosure:
Interest paid		4,267	4,547	3,359
Parent Company
Operating activities
Net income attributable to Huntington		2,211	1,940	1,951
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed net income of subsidiaries		(1,755)	(150)	(513)
Depreciation, amortization, and accretion		9	7	0
Other, net		278	(121)	192
Net cash provided by operating activities		743	1,676	1,630
Investing activities
Investment in subsidiaries		0	(1,750)	0
Repayments from subsidiaries		0	1,107	503
Advances to subsidiaries		(450)	(1,700)	(1,753)
Net cash received from business combinations		13	0	0
Other, net		(27)	(21)	(10)
Net cash used in investing activities		(464)	(2,364)	(1,260)
Financing activities
Net proceeds from issuance of long-term debt		0	2,995	1,250
Repayment of long-term debt		(489)	(734)	(323)
Dividends paid on common and preferred stock		(1,016)	(1,047)	(1,034)
Net proceeds from issuance of preferred stock		741	0	317
Repurchase/redemption of preferred stock		0	(410)	(82)
Other, net		(30)	(14)	(22)
Net cash provided by financing activities		(794)	790	106
Increase in cash and cash equivalents		(515)	102	476
Cash and cash equivalents at beginning of period		4,103	4,001	3,525
Cash and cash equivalents at end of period		3,588	4,103	4,001
Supplemental disclosure:
Interest paid		384	332	228
Non-cash activity:
Fair value of long-term debt assumed in business combination		$ 159	$ 0	$ 0

[1] Includes cash and due from banks and interest-earning deposits at the FRB, included within Interest-earning deposits with banks on our Consolidated Balance Sheets.