Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	RSUs	PSUs	Total common shareholders’ equity	Total common shareholders’ equity RSUs	Total common shareholders’ equity PSUs	Common stock	Common stock RSUs	Common stock PSUs	Additional paid-in capital	Additional paid-in capital RSUs	Additional paid-in capital PSUs	Retained earnings	Accumulated other comprehensive income (loss), net	Noncontrolling interest
Beginning balance at Dec. 31, 2021	$ 1,432,695			$ 1,432,602			$ 47,549			$ 892,529			$ 486,666	$ 5,858	$ 93
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to FB Financial Corporation and noncontrolling interest	124,571			124,555									124,555		16
Other comprehensive income (loss), net of taxes	(175,291)			(175,291)										(175,291)
Repurchase of common stock	(39,979)			(39,979)			(997)			(38,982)
Stock based compensation expense	9,857			9,857			3			9,854
Restricted stock and performance-based restricted stock units vested, net of taxes		$ (2,842)			$ (2,842)			$ 156			$ (2,998)
Shares issued under employee stock purchase program	1,212			1,212			27			1,185
Dividends declared	(24,689)			(24,689)									(24,689)
Noncontrolling interest distribution	(16)														(16)
Ending balance at Dec. 31, 2022	1,325,518			1,325,425			46,738			861,588			586,532	(169,433)	93
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to FB Financial Corporation and noncontrolling interest	120,240			120,224									120,224		16
Other comprehensive income (loss), net of taxes	34,708			34,708										34,708
Repurchase of common stock	(4,944)			(4,944)			(136)			(4,808)
Stock based compensation expense	10,381			10,381			9			10,372
Restricted stock and performance-based restricted stock units vested, net of taxes		(2,064)	$ (1,315)		(2,064)	$ (1,315)		149	$ 68		(2,213)	$ (1,383)
Shares issued under employee stock purchase program	723			723			21			702
Dividends declared	(28,344)			(28,344)									(28,344)
Noncontrolling interest distribution	(16)														(16)
Ending balance at Dec. 31, 2023	1,454,887			1,454,794			46,849			864,258			678,412	(134,725)	93
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to FB Financial Corporation and noncontrolling interest	116,051			116,035									116,035		16
Other comprehensive income (loss), net of taxes	33,041			33,041										33,041
Repurchase of common stock	(12,699)			(12,699)			(353)			(12,346)
Stock based compensation expense	9,485			9,485			6			9,479
Restricted stock and performance-based restricted stock units vested, net of taxes		$ (1,502)	$ (344)		$ (1,502)	$ (344)		$ 110	$ 30		$ (1,612)	$ (374)
Shares issued under employee stock purchase program	882			882			21			861
Dividends declared	(32,154)			(32,154)									(32,154)
Noncontrolling interest distribution	(16)														(16)
Ending balance at Dec. 31, 2024	$ 1,567,631			$ 1,567,538			$ 46,663			$ 860,266			$ 762,293	$ (101,684)	$ 93