CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions		Total	Series B	Series D	Adjustment to reflect adoption of ASU 2023-02	Preferred Stock	Preferred Stock Series B	Preferred Stock Series D	Common Stock	Capital Surplus	Retained Earnings	Retained Earnings Series B	Retained Earnings Series D	Retained Earnings Adjustment to reflect adoption of ASU 2023-02	Accumulated Other Comprehensive Income (Loss)		Noncontrolling Interest
Preferred stock, balance, beginning of period (in shares) at Dec. 31, 2023						26,750
Common stock, balance, beginning of period (in shares) at Dec. 31, 2023									558,838,694
Balance, beginning of period at Dec. 31, 2023		$ 9,291			$ 8	$ 520			$ 349	$ 5,351	$ 3,964			$ 8	$ (1,188)	[1]	$ 295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		197									192						5
Other comprehensive income (loss)		(83)													(83)	[1]
Cash dividends declared:
Preferred stock		(8)									(8)
Common stock		(84)									(84)
Common stock repurchased (in shares)	[2]								(11,051,980)
Common stock repurchased	[2]	(159)							$ (7)	(152)
Excise tax on common stock repurchased		(2)								(2)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									850,272
Stock options exercised and restricted stock awards		0
Stock-based compensation expense		18							$ 1	17
Dividends declared - noncontrolling interest of subsidiary preferred stock		(5)															(5)
Preferred stock, balance, ending of period (in shares) at Mar. 31, 2024						26,750
Common stock, balance, ending of period (in shares) at Mar. 31, 2024									548,636,986
Balance, ending of period at Mar. 31, 2024		9,173				$ 520			$ 343	5,214	4,072				(1,271)	[1]	295
Preferred stock, balance, beginning of period (in shares) at Dec. 31, 2023						26,750
Common stock, balance, beginning of period (in shares) at Dec. 31, 2023									558,838,694
Balance, beginning of period at Dec. 31, 2023		9,291			$ 8	$ 520			$ 349	5,351	3,964			$ 8	(1,188)	[1]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		624
Other comprehensive income (loss)		199													199
Preferred stock, balance, ending of period (in shares) at Sep. 30, 2024						16,750
Common stock, balance, ending of period (in shares) at Sep. 30, 2024									532,180,686
Balance, ending of period at Sep. 30, 2024		9,316				$ 426			$ 333	4,947	4,304				(989)	[1]	295
Preferred stock, balance, beginning of period (in shares) at Mar. 31, 2024						26,750
Common stock, balance, beginning of period (in shares) at Mar. 31, 2024									548,636,986
Balance, beginning of period at Mar. 31, 2024		9,173				$ 520			$ 343	5,214	4,072				(1,271)	[1]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		204									199						5
Other comprehensive income (loss)		(10)													(10)	[1]
Cash dividends declared:
Preferred stock		(8)									(8)
Common stock		(84)									(84)
Series B and Series D preferred stock redemption (in shares)								(10,000)
Series B and Series D preferred stock redemption				$ (100)				$ (94)					$ (6)
Excise tax on preferred stock redemption		(1)									(1)
Common stock repurchased (in shares)	[2]								(14,896,091)
Common stock repurchased	[2]	(228)							$ (9)	(219)
Excise tax on common stock repurchased		(1)								(1)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									3,134,855
Stock options exercised and restricted stock awards		2							$ 1	1
Stock-based compensation expense		13							$ 1	12
Dividends declared - noncontrolling interest of subsidiary preferred stock		(5)															(5)
Preferred stock, balance, ending of period (in shares) at Jun. 30, 2024						16,750
Common stock, balance, ending of period (in shares) at Jun. 30, 2024									536,875,750
Balance, ending of period at Jun. 30, 2024		8,955				$ 426			$ 336	5,007	4,172				(1,281)	[1]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		223									218						5
Other comprehensive income (loss)		292													292	[1]
Cash dividends declared:
Preferred stock		(5)									(5)
Common stock		(81)									(81)
Common stock repurchased (in shares)	[2]								(4,742,640)
Common stock repurchased	[2]	(75)							$ (3)	(72)
Excise tax on common stock repurchased		(1)								(1)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									47,576
Stock options exercised and restricted stock awards		0
Stock-based compensation expense		13								13
Dividends declared - noncontrolling interest of subsidiary preferred stock		(5)															(5)
Preferred stock, balance, ending of period (in shares) at Sep. 30, 2024						16,750
Common stock, balance, ending of period (in shares) at Sep. 30, 2024									532,180,686
Balance, ending of period at Sep. 30, 2024		9,316				$ 426			$ 333	4,947	4,304				(989)	[1]	295
Preferred stock, balance, beginning of period (in shares) at Dec. 31, 2024						16,750
Common stock, balance, beginning of period (in shares) at Dec. 31, 2024									524,280,412
Balance, beginning of period at Dec. 31, 2024		9,111				$ 426			$ 328	4,808	4,382				(1,128)	[3]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		222									218						4
Other comprehensive income (loss)		145													145	[3]
Cash dividends declared:
Preferred stock		(5)									(5)
Common stock		(78)									(78)
Common stock repurchased (in shares)	[4]								(17,657,334)
Common stock repurchased	[4]	(365)							$ (11)	(354)
Excise tax on common stock repurchased		(3)								(3)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									692,106
Stock options exercised and restricted stock awards		3								3
Stock-based compensation expense		18								18
Dividends declared - noncontrolling interest of subsidiary preferred stock		(4)															(4)
Preferred stock, balance, ending of period (in shares) at Mar. 31, 2025						16,750
Common stock, balance, ending of period (in shares) at Mar. 31, 2025									507,315,184
Balance, ending of period at Mar. 31, 2025		9,044				$ 426			$ 317	4,472	4,517				(983)	[3]	295
Preferred stock, balance, beginning of period (in shares) at Dec. 31, 2024						16,750
Common stock, balance, beginning of period (in shares) at Dec. 31, 2024									524,280,412
Balance, beginning of period at Dec. 31, 2024		9,111				$ 426			$ 328	4,808	4,382				(1,128)	[3]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		732
Other comprehensive income (loss)		$ 279													279
Cash dividends declared:
Series B and Series D preferred stock redemption											(3)
Preferred stock, balance, ending of period (in shares) at Sep. 30, 2025		8,750	0			8,750
Common stock, balance, ending of period (in shares) at Sep. 30, 2025									500,367,901
Balance, ending of period at Sep. 30, 2025		$ 9,244				$ 349			$ 313	4,288	4,848				(849)	[3]	295
Preferred stock, balance, beginning of period (in shares) at Mar. 31, 2025						16,750
Common stock, balance, beginning of period (in shares) at Mar. 31, 2025									507,315,184
Balance, beginning of period at Mar. 31, 2025		9,044				$ 426			$ 317	4,472	4,517				(983)	[3]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		245									241						4
Other comprehensive income (loss)		71													71	[3]
Cash dividends declared:
Preferred stock		(8)									(8)
Common stock		(79)									(79)
Common stock repurchased (in shares)	[4]								(1,455,166)
Common stock repurchased	[4]	(27)							$ (1)	(26)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									2,975,762
Stock options exercised and restricted stock awards		0
Stock-based compensation expense		15							$ 2	13
Dividends declared - noncontrolling interest of subsidiary preferred stock		(4)															(4)
Preferred stock, balance, ending of period (in shares) at Jun. 30, 2025						16,750
Common stock, balance, ending of period (in shares) at Jun. 30, 2025									508,835,780
Balance, ending of period at Jun. 30, 2025		9,257				$ 426			$ 318	4,459	4,671				(912)	[3]	295
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		266									262						4
Other comprehensive income (loss)		63													63	[3]
Cash dividends declared:
Preferred stock		(5)									(5)
Common stock		(77)									(77)
Series B and Series D preferred stock redemption (in shares)							(8,000)
Series B and Series D preferred stock redemption			$ (80)				$ (77)				(3)	$ (3)
Common stock repurchased (in shares)	[4]								(8,603,476)
Common stock repurchased	[4]	(191)							$ (5)	(186)
Excise tax on common stock repurchased		(2)								(2)
Common stock issued for:
Stock options exercised and restricted stock awards (in shares)									135,597
Stock options exercised and restricted stock awards		2								2
Stock-based compensation expense		15								15
Dividends declared - noncontrolling interest of subsidiary preferred stock		$ (4)															(4)
Preferred stock, balance, ending of period (in shares) at Sep. 30, 2025		8,750	0			8,750
Common stock, balance, ending of period (in shares) at Sep. 30, 2025									500,367,901
Balance, ending of period at Sep. 30, 2025		$ 9,244				$ 349			$ 313	$ 4,288	$ 4,848				$ (849)	[3]	$ 295

[1] Due to the nature of the preferred stock issued by FHN and its subsidiaries, all components of other comprehensive income (loss) have been attributed solely to FHN as the controlling interest holder.

[2] Includes $154 million, $212 million, and $75 million repurchased during first, second, and third quarter, respectively, under FHN's $650 million general purchase program approved in January 2024 and terminated in October 2024.

[3] Due to the nature of the preferred stock issued by FHN and its subsidiaries, all components of other comprehensive income (loss) have been attributed solely to FHN as the controlling interest holder.

[4] Includes $360 million, $9 million, and $190 million repurchased during first, second, and third quarter, respectively, under FHN's $1 billion general purchase program approved in October 2024