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 loss, net	Noncontrolling interest
Beginning 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	27,950			27,950									27,950
Other comprehensive income, net of taxes	2,241			2,241										2,241
Stock-based compensation expense	2,820			2,820			1			2,819
Restricted stock and performance-based restricted stock units vested, net of taxes		$ (281)	$ (345)		$ (281)	$ (345)		$ 11	$ 25		$ (292)	$ (370)
Shares issued under employee stock purchase program	399			399			11			388
Dividends declared	(8,052)			(8,052)									(8,052)
Ending balance at Mar. 31, 2024	1,479,619			1,479,526			46,897			866,803			698,310	(132,484)	93
Beginning balance at Dec. 31, 2024	1,567,631			1,567,538			46,663			860,266			762,293	(101,684)	93
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to FB Financial Corporation and noncontrolling interest	39,361			39,361									39,361
Other comprehensive income, net of taxes	9,731			9,731										9,731
Repurchase of common stock	(9,892)			(9,892)			(209)			(9,683)
Stock-based compensation expense	4,831			4,831			1			4,830
Restricted stock and performance-based restricted stock units vested, net of taxes		$ (441)	$ (621)		$ (441)	$ (621)		$ 19	$ 33		$ (460)	$ (654)
Shares issued under employee stock purchase program	424			424			8			416
Dividends declared	(8,969)			(8,969)									(8,969)
Ending balance at Mar. 31, 2025	$ 1,602,055			$ 1,601,962			$ 46,515			$ 854,715			$ 792,685	$ (91,953)	$ 93