Consolidated statements of income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest income:
Interest and fees on loans	$ 76,504	$ 67,639	$ 201,350	$ 194,363
Interest on securities
Taxable	2,286	3,137	7,961	10,254
Tax-exempt	1,933	1,174	4,956	3,478
Other	404	1,292	2,141	2,799
Total interest income	81,127	73,242	216,408	210,894
Interest expense:
Deposits	10,573	13,522	32,050	38,865
Borrowings	1,726	1,415	3,944	3,685
Total interest expense	12,299	14,937	35,994	42,550
Net interest income	68,828	58,305	180,414	168,344
Provision for credit losses	45,834	1,831	97,837	4,103
Provision for credit losses on unfunded commitments	9,567	0	13,050	0
Net interest income after provisions for credit losses	13,427	56,474	69,527	164,241
Noninterest income:
Gain (loss) from securities, net	583	(20)	618	75
(Loss) gain on sales or write-downs of other real estate owned	(1,505)	(126)	(1,368)	112
Gain (loss) from other assets	226	44	(156)	52
Other income	5,133	2,114	10,395	5,598
Total noninterest income	97,026	38,145	221,217	100,163
Noninterest expenses:
Salaries, commissions and employee benefits	67,676	40,880	166,556	112,495
Occupancy and equipment expense	4,892	4,058	13,166	12,107
Legal and professional fees	1,917	1,993	5,427	5,412
Data processing	2,994	2,816	8,229	7,843
Merger costs	20,730	295	25,366	4,699
Amortization of core deposit and other intangibles	1,417	1,197	3,825	3,180
Advertising	2,256	1,895	7,236	7,066
Other expense	16,210	9,801	37,425	29,353
Total noninterest expense	118,092	62,935	267,230	182,155
(Loss) income before income taxes	(7,639)	31,684	23,514	82,249
Income tax (benefit) expense	(2,040)	7,718	5,495	20,007
Net (loss) income	(5,599)	23,966	18,019	62,242
Net income applicable to noncontrolling interests	0	0	0	0
Net (loss) income applicable to FB Financial Corporation	$ (5,599)	$ 23,966	$ 18,019	$ 62,242
(Loss) earnings per common share
Basic (in dollars per share)	$ (0.14)	$ 0.77	$ 0.52	$ 2.01
Diluted (in dollars per share)	$ (0.14)	$ 0.76	$ 0.52	$ 1.97
Mortgage banking income
Noninterest income:
Mortgage banking income, service charges on deposit accounts, ATM and interchange fees, investment services and trust income	$ 84,686	$ 29,193	$ 189,599	$ 74,740
Service charges on deposit accounts
Noninterest income:
Mortgage banking income, service charges on deposit accounts, ATM and interchange fees, investment services and trust income	2,162	2,416	6,583	6,822
ATM and interchange fees
Noninterest income:
Mortgage banking income, service charges on deposit accounts, ATM and interchange fees, investment services and trust income	3,913	3,188	10,653	8,846
Investment services and trust income
Noninterest income:
Mortgage banking income, service charges on deposit accounts, ATM and interchange fees, investment services and trust income	$ 1,828	$ 1,336	$ 4,893	$ 3,918