Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net income attributable to FB Financial Corporation and noncontrolling interest	$ 36,381,000	$ 35,236,000
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization of fixed assets and software	2,228,000	2,036,000
Amortization of core deposit and other intangibles	990,000	1,244,000
Amortization of issuance costs on subordinated debt	97,000	97,000
Capitalization of mortgage servicing rights	(1,788,000)	(9,812,000)
Net change in fair value of mortgage servicing rights	5,274,000	(19,351,000)
Stock-based compensation expense	2,285,000	2,582,000
Provision for credit losses	4,997,000	(6,129,000)
Provision for credit losses on unfunded commitments	(4,506,000)	1,882,000
Provision for mortgage loan repurchases	(250,000)	(389,000)
(Accretion) amortization of discounts and premiums on acquired loans, net	(319,000)	2,352,000
Amortization of premiums and accretion of discounts on securities, net	1,382,000	1,992,000
(Gain) loss from securities, net	(69,000)	152,000
Originations of loans held for sale	(295,760,000)	(993,733,000)
Proceeds from sale of loans held for sale	340,108,000	1,330,701,000
Gain on sale and change in fair value of loans held for sale	(8,635,000)	(21,675,000)
Net loss on write-downs of other real estate owned and other assets	183,000	434,000
Provision for deferred income taxes	1,396,000	9,313,000
Earnings on bank-owned life insurance	(605,000)	(354,000)
Changes in:
Operating lease assets and liabilities, net	580,000	(190,000)
Other assets and interest receivable	62,512,000	(62,043,000)
Accrued expenses and other liabilities	(48,099,000)	13,900,000
Net cash provided by operating activities	98,382,000	288,245,000
Activity in available-for-sale securities:
Maturities, prepayments and calls	26,827,000	57,443,000
Purchases	(660,000)	(170,093,000)
Net change in loans	(52,540,000)	(362,408,000)
Sales of FHLB stock	21,637,000	0
Purchases of FHLB stock	(6,365,000)	(2,216,000)
Purchases of premises and equipment	(9,450,000)	(601,000)
Proceeds from the sale of other real estate owned and other assets	2,031,000	121,000
Proceeds from bank-owned life insurance	236,000	0
Net cash used in investing activities	(18,284,000)	(477,754,000)
Cash flows from financing activities:
Net increase in demand deposits	251,069,000	238,893,000
Net increase (decrease) in time deposits	74,896,000	(75,765,000)
Net decrease in securities sold under agreements to repurchase and federal funds purchased	(48,815,000)	(14,779,000)
Net decrease in short-term FHLB advances	(50,000,000)	0
Share based compensation withholding payments	(2,597,000)	(1,488,000)
Net proceeds from sale of common stock under employee stock purchase program	321,000	687,000
Repurchase of common stock	(4,944,000)	(6,203,000)
Dividends paid on common stock	(6,994,000)	(6,194,000)
Dividend equivalent payments made upon vesting of equity compensation	(135,000)	(71,000)
Net cash provided by financing activities	212,801,000	135,080,000
Net change in cash and cash equivalents	292,899,000	(54,429,000)
Cash and cash equivalents at beginning of the period	1,027,052,000	1,797,740,000
Cash and cash equivalents at end of the period	1,319,951,000	1,743,311,000
Supplemental cash flow information:
Interest paid	52,634,000	8,631,000
Taxes (refunded) paid, net	(904,000)	72,000
Supplemental noncash disclosures:
Transfers from loans to other real estate owned	235,000	563,000
Transfers from loans to loans held for sale	7,126,000	8,700,000
Transfers from loans held for sale to loans	776,000	47,956,000
Decrease in rebooked GNMA loans under optional repurchase program	(5,683,000)	0
Trade date payable - securities	245,000	0
Dividends declared not paid on restricted stock units	48,000	60,000
Right-of-use assets obtained in exchange for operating lease liabilities	$ 3,375,000	$ 283,000