Consolidated Statements of Comprehensive (Loss) Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 35,236	$ 52,874
Other comprehensive loss, net of tax:
Net change in unrealized loss in available-for-sale securities, net of tax benefits of $(27,483) and $(3,452)	(78,175)	(11,848)
Reclassification adjustment for gain on sale of securities included in net income, net of tax expenses of $1 and $2	(1)	(5)
Amount of gain recognized in other comprehensive (loss) income, net of tax expense of $273 and $112	774	316
Total other comprehensive loss, net of tax	(77,402)	(11,537)
Comprehensive (loss) income	(42,166)	41,337
Comprehensive income applicable to noncontrolling interest	0	0
Comprehensive (loss) income applicable to FB Financial Corporation	$ (42,166)	$ 41,337