Consolidated Statements of Comprehensive (Loss) Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 31,831	$ 45,290	$ 86,420	$ 141,466
Other comprehensive loss, net of tax:
Net change in unrealized loss in available-for-sale securities, net of tax benefits of $(23,750), $(2,054), $(68,576) and $(4,708)	(67,353)	(5,818)	(194,761)	(15,380)
Reclassification adjustment for gain on sale of securities included in net income, net of tax expenses of $0, $19, $1 and $23	(1)	(56)	(3)	(67)
Net change in unrealized gain in hedging activities, net of tax expenses of $145, $38, $517 and $173	409	106	1,466	489
Total other comprehensive loss, net of tax	(66,945)	(5,768)	(193,298)	(14,958)
Comprehensive (loss) income applicable to FB Financial Corporation and noncontrolling interest	(35,114)	39,522	(106,878)	126,508
Comprehensive income applicable to noncontrolling interest	0	0	8	8
Comprehensive (loss) income applicable to FB Financial Corporation	$ (35,114)	$ 39,522	$ (106,886)	$ 126,500