Reliant Bancorp (RBNC) 10-Q 5 Nov 21 2021 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 04, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-37391
Entity Registrant Name	Reliant Bancorp, Inc.
Entity Incorporation, State or Country Code	TN
Entity Tax Identification Number	37-1641316
Entity Address, Address Line One	1736 Carothers Parkway,
Entity Address, Address Line Two	Suite 100,
Entity Address, City or Town	Brentwood,
Entity Address, State or Province	TN
Entity Address, Postal Zip Code	37027
City Area Code	615
Local Phone Number	221-2020
Title of 12(b) Security	Common Stock, $1.00 par value per share
Trading Symbol	RBNC
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		16,576,680
Entity Central Index Key	0001606440
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS
Cash and due from banks	$ 13,270	$ 13,717
Interest-bearing deposits in financial institutions	66,155	79,756
Federal funds sold	1,002	1,572
Total cash and cash equivalents	80,427	95,045
Securities available for sale	254,416	256,653
Loans	2,389,833	2,300,783
Less: allowance for loan losses	(20,897)	(20,636)
Loans, net	2,368,936	2,280,147
Mortgage loans held for sale, net	62,543	147,524
Accrued interest receivable	14,374	14,889
Premises and equipment, net	27,519	31,462
Operating leases right of use assets	12,427	13,103
Restricted equity securities, at cost	15,770	16,551
Other real estate, net	3,088	1,246
Cash surrender value of life insurance contracts	78,460	77,988
Deferred tax assets, net	5,788	7,121
Goodwill	54,396	54,396
Core deposit intangibles	9,978	11,347
Other assets	25,437	19,063
TOTAL ASSETS	3,013,559	3,026,535
Deposits
Noninterest-bearing demand	626,598	575,289
Interest-bearing demand	410,923	350,392
Savings and money market deposit accounts	989,677	857,210
Time	520,507	796,344
Total deposits	2,547,705	2,579,235
Accrued interest payable	2,302	2,571
Subordinated debentures	70,821	70,446
Federal Home Loan Bank advances	0	10,000
Operating leases liabilities	13,605	14,231
Other liabilities	22,811	28,079
TOTAL LIABILITIES	2,657,244	2,704,562
Preferred stock, $1 par value per share; 10,000,000 shares authorized, zero shares issued to date	0	0
Common stock, $1 par value per share; 30,000,000 shares authorized; 16,682,928 and 16,654,409 shares issued and outstanding at September 30, 2021, and December 31, 2020, respectively	16,683	16,654
Additional paid-in capital	234,696	233,331
Retained earnings	98,182	65,757
Accumulated other comprehensive income	6,754	6,231
TOTAL SHAREHOLDERS’ EQUITY	356,315	321,973
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$ 3,013,559	$ 3,026,535

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	30,000,000	30,000,000
Common stock, shares issued (in shares)	16,682,928	16,654,409
Common stock, shares outstanding (in shares)	16,682,928	16,654,409

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
INTEREST INCOME
Interest and fees on loans	$ 30,817	$ 32,895	$ 92,989	$ 86,987
Interest and fees on loans held for sale	1,184	1,037	4,322	2,412
Interest on investment securities, taxable	786	399	2,059	978
Interest on investment securities, nontaxable	928	1,186	3,369	3,874
Restricted equity securities and other	215	251	668	738
TOTAL INTEREST INCOME	33,930	35,768	103,407	94,989
Deposits
Demand	153	236	641	554
Savings and money market deposit accounts	441	1,162	1,927	3,668
Time	3,348	2,735	10,314	9,577
Federal Home Loan Bank advances and other borrowings	9	104	26	613
Subordinated debentures	980	992	2,913	2,967
TOTAL INTEREST EXPENSE	4,931	5,229	15,821	17,379
NET INTEREST INCOME	28,999	30,539	87,586	77,610
PROVISION FOR LOAN LOSSES	0	1,500	0	7,400
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	28,999	29,039	87,586	70,210
NONINTEREST INCOME
Service charges on deposit accounts	1,678	1,583	4,895	4,172
Gains on mortgage loans sold, net	4,218	3,784	12,124	7,605
Gain on securities transactions, net	2,419	0	5,514	327
Income from bank owned life insurance	2,181	386	3,172	1,073
Other noninterest income	373	249	811	529
TOTAL NONINTEREST INCOME	10,869	6,002	26,516	13,706
NONINTEREST EXPENSE
Salaries and employee benefits	12,426	12,184	38,571	33,885
Occupancy	2,038	2,054	6,045	5,566
Data processing and software	2,265	2,240	6,756	6,085
Professional fees	526	775	2,127	1,933
Regulatory fees	328	365	1,032	1,356
Merger expenses	1,453	77	1,453	6,895
Other operating expense	3,345	2,639	8,545	6,476
TOTAL NONINTEREST EXPENSE	22,381	20,334	64,529	62,196
INCOME BEFORE PROVISION FOR INCOME TAXES	17,487	14,707	49,573	21,720
INCOME TAX EXPENSE	3,551	2,800	9,733	3,524
CONSOLIDATED NET INCOME	13,936	11,907	39,840	18,196
NONCONTROLLING INTEREST IN NET (INCOME) LOSS OF SUBSIDIARY	(647)	(374)	(1,357)	990
NET INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 13,289	$ 11,533	$ 38,483	$ 19,186
Basic net income attributable to common shareholders, per share (in dollars per share)	$ 0.80	$ 0.70	$ 2.31	$ 1.27
Diluted net income attributable to common shareholders, per share (in dollars per share)	$ 0.79	$ 0.69	$ 2.29	$ 1.27

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 13,936	$ 11,907	$ 39,840	$ 18,196
Other comprehensive income:
Unrealized holdings (losses) gains arising during the period	(1,864)	1,365	(967)	3,306
Reclassification adjustment for gains included in net income	(2,419)	0	(5,514)	(327)
Tax effect	1,119	(357)	1,694	(779)
Net of tax	(3,164)	1,008	(4,787)	2,200
Unrealized (losses) gains on cash flow hedges
Unrealized holdings (losses) gains arising during the period	(113)	508	2,040	(6,448)
Reclassification adjustment for losses included in net income	2,290	0	5,149	0
Tax effect	(568)	(133)	(1,879)	1,686
Net of tax	1,609	375	5,310	(4,762)
Other comprehensive (loss) income	(1,555)	1,383	523	(2,562)
Comprehensive income	12,381	13,290	40,363	15,634
Comprehensive (income) loss attributable to noncontrolling interest	(647)	(374)	(1,357)	990
Comprehensive income attributable to the controlling interest	$ 11,734	$ 12,916	$ 39,006	$ 16,624

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY - UNAUDITED - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	RETAINED EARNINGS	RETAINED EARNINGSCumulative Effect, Period of Adoption, Adjustment	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	NONCONTROLLING INTEREST
Beginning balance (in shares) at Dec. 31, 2019			11,206,254
Beginning balance at Dec. 31, 2019	$ 223,753	$ 100	$ 11,206	$ 167,006	$ 40,472	$ 100	$ 5,069	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	349			349
Exercise of stock options (in shares)			868
Exercise of stock options	8		$ 1	7
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			(3,837)
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	(73)		$ (4)	(69)
Conversion shares issued to shareholders (in shares)			811,210
Conversion shares issued to shareholders	18,041		$ 811	17,230
Noncontrolling interest contributions	976							976
Cash dividend declared to common shareholders	(1,207)				(1,207)
Net income (loss)	(1,191)				(215)			(976)
Other comprehensive income (loss)	(6,084)						(6,084)
Ending balance (in shares) at Mar. 31, 2020			12,014,495
Ending balance at Mar. 31, 2020	234,672		$ 12,014	184,523	39,150		(1,015)	0
Beginning balance (in shares) at Dec. 31, 2019			11,206,254
Beginning balance at Dec. 31, 2019	223,753	$ 100	$ 11,206	167,006	40,472	$ 100	5,069	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	18,196
Other comprehensive income (loss)	(2,562)
Ending balance (in shares) at Sep. 30, 2020			16,634,572
Ending balance at Sep. 30, 2020	307,086		$ 16,635	232,738	55,206		2,507	0
Beginning balance (in shares) at Mar. 31, 2020			12,014,495
Beginning balance at Mar. 31, 2020	234,672		$ 12,014	184,523	39,150		(1,015)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	485			485
Exercise of stock options (in shares)			1,021
Exercise of stock options	15		$ 1	14
Employee Stock Purchase Plan stock issuance (in shares)			8,344
Employee Stock Purchase Plan stock issuance	116		$ 8	108
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			1,325
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	0		$ 2	(2)
Conversion shares issued to shareholders (in shares)			4,606,419
Conversion shares issued to shareholders	51,915		$ 4,607	47,308
Noncontrolling interest contributions	388							388
Cash dividend declared to common shareholders	(1,667)				(1,667)
Net income (loss)	7,480				7,868			(388)
Other comprehensive income (loss)	2,139						2,139
Ending balance (in shares) at Jun. 30, 2020			16,631,604
Ending balance at Jun. 30, 2020	295,543		$ 16,632	232,436	45,351		1,124	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	349			349
Exercise of stock options (in shares)			4,655
Exercise of stock options	66		$ 5	61
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			(1,687)
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	(110)		$ (2)	(108)
Noncontrolling interest contributions	(374)							(374)
Cash dividend declared to common shareholders	(1,678)				(1,678)
Net income (loss)	11,907				11,533			374
Other comprehensive income (loss)	1,383						1,383
Ending balance (in shares) at Sep. 30, 2020			16,634,572
Ending balance at Sep. 30, 2020	$ 307,086		$ 16,635	232,738	55,206		2,507	0
Beginning balance (in shares) at Dec. 31, 2020	16,654,409		16,654,409
Beginning balance at Dec. 31, 2020	$ 321,973		$ 16,654	233,331	65,757		6,231	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	339			339
Exercise of stock options (in shares)			600
Exercise of stock options	8		$ 1	7
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			(594)
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	(11)		$ (1)	(10)
Noncontrolling interest contributions	(570)							(570)
Cash dividend declared to common shareholders	(2,015)				(2,015)
Net income (loss)	12,719				12,149			570
Other comprehensive income (loss)	(744)						(744)
Ending balance (in shares) at Mar. 31, 2021			16,654,415
Ending balance at Mar. 31, 2021	$ 331,699		$ 16,654	233,667	75,891		5,487	0
Beginning balance (in shares) at Dec. 31, 2020	16,654,409		16,654,409
Beginning balance at Dec. 31, 2020	$ 321,973		$ 16,654	233,331	65,757		6,231	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)	1,702
Net income (loss)	$ 39,840
Other comprehensive income (loss)	$ 523
Ending balance (in shares) at Sep. 30, 2021	16,682,928		16,682,928
Ending balance at Sep. 30, 2021	$ 356,315		$ 16,683	234,696	98,182		6,754	0
Beginning balance (in shares) at Mar. 31, 2021			16,654,415
Beginning balance at Mar. 31, 2021	331,699		$ 16,654	233,667	75,891		5,487	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	468			468
Employee Stock Purchase Plan stock issuance (in shares)			18,986
Employee Stock Purchase Plan stock issuance	298		$ 20	278
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			(890)
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	(24)		$ (1)	(23)
Noncontrolling interest contributions	(140)							(140)
Cash dividend declared to common shareholders	(2,019)				(2,019)
Net income (loss)	13,185				13,045			140
Other comprehensive income (loss)	2,822						2,822
Ending balance (in shares) at Jun. 30, 2021			16,672,511
Ending balance at Jun. 30, 2021	346,289		$ 16,673	234,390	86,917		8,309	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation expense	458			458
Exercise of stock options (in shares)			1,102
Exercise of stock options	15		$ 1	14
Employee Stock Purchase Plan stock issuance (in shares)			2,795
Employee Stock Purchase Plan stock issuance	66		$ 3	63
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures (in shares)			6,520
Restricted stock awards, net of taxes withheld and stock and dividend forfeitures	(223)		$ 6	(229)
Noncontrolling interest contributions	(647)							(647)
Cash dividend declared to common shareholders	(2,024)				(2,024)
Net income (loss)	13,936				13,289			647
Other comprehensive income (loss)	$ (1,555)						(1,555)
Ending balance (in shares) at Sep. 30, 2021	16,682,928		16,682,928
Ending balance at Sep. 30, 2021	$ 356,315		$ 16,683	$ 234,696	$ 98,182		$ 6,754	$ 0

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY - UNAUDITED (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Cash dividends declared to common shareholders (in dollars per share)	$ 0.12	$ 0.12	$ 0.12	$ 0.10	$ 0.10	$ 0.10

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - UNAUDITED - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
OPERATING ACTIVITIES
Consolidated net income	$ 39,840	$ 18,196
Adjustments to reconcile consolidated net income to net cash (used in) provided by operating activities
Provision for loan losses	0	7,400
Deferred income taxes	1,148	2,003
Loss (gain) on disposal of premises and equipment	74	(1)
Depreciation of premises and equipment	2,127	2,084
Net amortization of securities	1,202	1,980
Net realized gains on sales of securities	(5,514)	(327)
Gains on mortgage loans sold, net	(12,124)	(7,605)
Stock-based compensation expense	1,265	1,183
Gain on other real estate	(33)	(24)
Provision for losses on other real estate	98	0
Earnings on bank-owned life insurance	(3,172)	(1,073)
Mortgage loans originated for resale	(699,551)	(327,521)
Proceeds from sale of mortgage loans	796,656	278,893
Right of use asset amortization	1,951	1,224
Other accretion, net of other amortization	(2,827)	(8,256)
Change in
Accrued interest receivable	515	(4,094)
Other assets	(3,729)	(3,794)
Accrued interest payable	(269)	(526)
Other liabilities	640	4,367
TOTAL ADJUSTMENTS	78,457	(54,087)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	118,297	(35,891)
INVESTING ACTIVITIES
Cash (used in) received from acquisitions, net	0	(8,500)
Activities in available for sale securities
Purchases	(68,164)	(31,179)
Sales	58,855	103,901
Maturities, prepayments and calls	8,730	10,370
Redemptions (purchases) of restricted equity securities	781	(1,867)
Net change in loans	(84,218)	(146,777)
Purchase of premises and equipment	(297)	(2,709)
Proceeds from sale of premises and equipment	51	257
Proceeds from sale of other real estate	126	2,273
NET CASH USED IN INVESTING ACTIVITIES	(84,136)	(74,231)
FINANCING ACTIVITIES
Net change in deposits	(31,493)	163,839
Proceeds from Federal Home Loan Bank advances	423,000	444,000
Payments on Federal Home Loan Bank advances	(433,000)	(463,156)
Issuance of ESPP shares and exercise of common stock options and warrants, net of repurchase of restricted shares	129	22
Noncontrolling interest contributions	(1,357)
Noncontrolling interest contributions		990
Cash dividends paid on common stock	(6,058)	(4,550)
NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES	(48,779)	146,145
NET CHANGE IN CASH AND CASH EQUIVALENTS	(14,618)	36,023
CASH AND CASH EQUIVALENTS - BEGINNING OF PERIOD	95,045	51,649
CASH AND CASH EQUIVALENTS - END OF PERIOD	80,427	87,672
Cash paid during the period for
Interest	15,752	20,508
Income taxes	7,790	4,565
Supplemental disclosures of non-cash transactions
Unrealized (loss) gain on securities available-for-sale	(7,128)	4,039
Unrealized gain (loss) on derivatives	7,836	(7,508)
Change in due to/from noncontrolling interest	(1,357)	990
Bank facilities no longer in use transferred to other real estate from premises and equipment	1,988	0
Loans foreclosed and transferred to other real estate	45	197
Right of use assets obtained in exchange for operating lease liabilities	1,302	11,973
BOLI proceeds receivable recognized in income	$ 2,699	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Reliant Bancorp, Inc. is a Tennessee corporation and the holding company for and the sole shareholder of Reliant Bank (the "Bank"), collectively, "the Company". Reliant Bancorp is registered as a bank holding company under the Bank Holding Company Act of 1956, as amended ("Bank Holding Company Act"). Reliant Bancorp has elected under the Bank Holding Company Act to be a financial holding company. Reliant Bank is a commercial bank chartered under Tennessee law and a member of the Federal Reserve System (the "Federal Reserve"). The Bank provides a full range of traditional banking products and services to business and consumer clients throughout Middle Tennessee. Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with instructions to Quarterly Report on Form 10-Q and, therefore, do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, and cash flows in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP"). All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods covered by the report have been included. The accompanying unaudited consolidated financial statements should be read in conjunction with the Company's consolidated financial statements and related notes appearing in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. Amounts in the footnotes are shown in thousands, except for numbers of shares, per share amounts and as otherwise noted. The consolidated financial statements as of and for the periods presented include Reliant Bancorp, Inc., its wholly-owned direct and indirect subsidiaries and Reliant Mortgage Ventures, LLC ("RMV"), of which the Bank controls 51% of the governance rights. As described in Note 11 to these unaudited consolidated financial statements, Reliant Bancorp, Inc. and Tennessee Community Bank Holdings, Inc. (“TCB Holdings”) merged effective on January 1, 2020, and Reliant Bancorp, Inc. and First Advantage Bancorp (“FABK”) merged effective April 1, 2020. Proposed Merger with United Community Banks, Inc. On July 14, 2021, United Community Banks, Inc. (NASDAQGS: UCBI) (“United”) and Reliant Bancorp announced the execution of a definitive merger agreement pursuant to which United will acquire Reliant Bancorp in an all-stock transaction with an aggregate value of approximately $517 million, or $30.58 per share of Reliant Bancorp common stock, based on United’s closing stock price of $31.07 on July 13, 2021. This agreement is subject to both regulatory and Reliant Bancorp shareholder approval. The transaction is expected to close in the first quarter of 2022. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions based on available information. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to determination of the allowance for loan losses, the valuation of other real estate, the valuation of debt and equity securities, the valuation of deferred tax assets and fair values of financial instruments. The consolidated financial statements as of September 30, 2021, and for the three and nine months ended September 30, 2021 and 2020, included herein have not been audited. The accounting and reporting policies of the Company conform to U.S. GAAP and Article 8 of Regulation S-X. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission, although the Company believes that the disclosures made are adequate to make the information not misleading. The accompanying consolidated financial statements reflect all adjustments which, in the opinion of management, are necessary to present a fair statement of the results for the interim periods presented. Such adjustments are of a normal recurring nature. The Company evaluates subsequent events through the date of filing. Certain prior period amounts have been reclassified to conform to the current period presentation. The results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. Recently Adopted Accounting Pronouncements Information about certain issued accounting standards updates is presented below. Also refer to Note 1 - Summary of Significant Accounting Policies, in the Company's Annual Report on Form 10-K for the year ended December 31, 2020 for additional information related to previously issued accounting standards updates. ASU 2019-12, “Income Taxes (Topic 740) - Simplifying the Accounting for Income Taxes.” The guidance issued in this update simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition for deferred tax liabilities for outside basis differences. ASU 2019-12 also simplifies aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. ASU 2019-12 was effective for us on January 1, 2021, and did not have a significant impact on our consolidated financial statements. ASU 2020-04, "Reference Rate Reform (Topic 848 ) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting." In March 2020, the Financial Accounting Standards Board (“FASB”) issued Topic 848 amendments to provide optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. It provides optional expedients and exceptions for applying generally accepted accounting principles to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this update are effective for all entities as of March 12, 2020 through December 31, 2022. The Company has evaluated the effect of the pronouncement on the consolidated financial statements, noting no significant impact. Newly Issued not yet Effective Accounting Standards ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts and requires enhanced disclosures related to the significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an organization’s portfolio. In addition, ASU 2016-13 amends the accounting for credit losses on available for sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 is expected to be effective for the Company on January 1, 2023. We are currently evaluating the potential impact of ASU 2016-13 on the Company's financial statements by developing an implementation plan to include assessment of processes, portfolio segmentation, model development, system requirements and the identification of data and resource needs, among other things. The adoption of ASU 2016-13 could result in an increase in the allowance for loan losses as a result of changing from an “incurred loss” model, which encompasses allowances for current known and inherent losses within the portfolio, to an “expected loss” model, which encompasses allowances for losses expected to be incurred over the life of the portfolio. Furthermore, ASU 2016-13 will necessitate that we establish an allowance for expected credit losses for certain debt securities and other financial assets. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Financial Instruments - Credit Losses (ASC 326), Derivatives and Hedging (ASC 815), and Financial Instruments (ASC 825) . The amendments in this ASU improve the codification by eliminating inconsistencies and providing clarifications. The amended guidance in this ASU related to credit losses is expected to be effective for the Company in conjunction with the adoption of the standard on January 1, 2023. The Company is currently evaluating the impact of these ASUs on the Company’s consolidated financial statements. While we are currently unable to reasonably estimate the impact of adopting these ASUs, we expect that the impact of adoption will be significantly influenced by the composition, characteristics and quality of the Company's loan and securities portfolios as well as the prevailing economic conditions and forecasts as of the adoption date.

Securities

Securities	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
SECURITIES	SECURITIES The amortized cost and fair value of available for sale securities and the related gross unrealized gains and losses recognized in accumulated other comprehensive income at September 30, 2021 and December 31, 2020 were as follows: September 30, 2021 Amortized Gross Gross Estimated U. S. Treasury and other U. S. government agencies $ 218 $ — $ — $ 218 State and municipal 161,733 10,039 (801) 170,971 Corporate bonds 27,000 1,160 (8) 28,152 Mortgage-backed securities - Residential 52,736 295 (208) 52,823 Asset-backed securities 2,270 1 (19) 2,252 Total $ 243,957 $ 11,495 $ (1,036) $ 254,416 December 31, 2020 Amortized Gross Gross Estimated U. S. Treasury and other U. S. government agencies $ 47 $ 1 $ — $ 48 State and municipal 184,102 16,963 (77) 200,988 Corporate bonds 23,750 397 (34) 24,113 Mortgage-backed securities - Residential 28,084 360 (2) 28,442 Asset-backed securities 3,083 1 (22) 3,062 Total $ 239,066 $ 17,722 $ (135) $ 256,653 Securities pledged at September 30, 2021 and December 31, 2020 had a carrying amount of $35,376 and $30,491, respectively, and were pledged to collateralize Federal Home Loan Bank ("FHLB") advances, Federal Reserve Bank ("FRB") advances and municipal deposits. Results from sales of securities were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Proceeds $ 23,104 $ 233 $ 58,855 $ 103,901 Gross gains 2,419 371 5,514 810 Gross losses — (371) — (483) The fair values of available for sale debt securities at September 30, 2021 by contractual maturity are provided below. Actual maturities may differ from contractual maturities for mortgage- and asset-backed securities since the underlying asset may be called or prepaid with or without penalty. Securities not due at a single maturity date are shown separately. Amortized Estimated Due within one year $ 218 $ 218 Due in one to five years 2,085 2,120 Due in five to ten years 31,473 33,239 Due after ten years 155,175 163,764 Mortgage-backed securities 52,736 52,823 Asset-backed securities 2,270 2,252 Total $ 243,957 $ 254,416 The following table shows available for sale securities with unrealized losses and their estimated fair value aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of September 30, 2021 and December 31, 2020, respectively: Less than 12 months 12 months or more Total Estimated Unrealized Estimated Unrealized Estimated Unrealized September 30, 2021 State and municipal $ 37,064 $ 801 $ — $ — $ 37,064 $ 801 Corporate bonds 1,742 8 — — 1,742 8 Mortgage-backed securities - Residential 33,283 207 74 1 33,357 208 Asset-backed securities — — 2,045 19 2,045 19 Total temporarily impaired $ 72,089 $ 1,016 $ 2,119 $ 20 $ 74,208 $ 1,036 December 31, 2020 State and municipal $ 9,475 $ 77 $ — $ — $ 9,475 $ 77 Corporate bonds 5,716 34 — — 5,716 34 Mortgage-backed securities - Residential 5,024 1 92 1 5,116 2 Asset-backed securities 729 2 2,013 20 2,742 22 Total temporarily impaired $ 20,944 $ 114 $ 2,105 $ 21 $ 23,049 $ 135 Management has the intent and ability to hold all securities in an unrealized loss position for the foreseeable future, and the decline in fair value is largely due to changes in interest rates. As the fair value is expected to recover as the securities approach their maturity date and/or market rates decline, we do not consider these securities to be other-than-temporarily impaired at September 30, 2021. There were 48 and 22 securities in an unrealized loss position as of September 30, 2021 and December 31, 2020, respectively.

Loans and Allowance for Loan Lo

Loans and Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2021
Receivables [Abstract]
LOANS AND ALLOWANCE FOR LOAN LOSSES	LOANS AND ALLOWANCE FOR LOAN LOSSES Loans at September 30, 2021 and December 31, 2020 were comprised as follows: September 30, 2021 December 31, 2020 Commercial, Industrial and Agricultural $ 450,710 $ 459,739 Real Estate 1-4 Family Residential 310,855 323,473 1-4 Family HELOC 100,895 100,525 Multi-family and Commercial 873,265 834,000 Construction, Land Development and Farmland 417,258 365,058 Consumer 234,734 213,863 Other 5,298 8,669 Gross loans 2,393,015 2,305,327 Less: Deferred loan fees 3,182 4,544 Less: Allowance for loan losses 20,897 20,636 Loans, net $ 2,368,936 $ 2,280,147 At September 30, 2021 and December 31, 2020, loans are recorded net of purchase discounts of $11,993 and $16,634, respectively. The Company pledged loans to the FHLB at September 30, 2021 and December 31, 2020 of $857,394 and $646,498, respectively. The Company utilizes a risk grading system to monitor the credit quality of the Company’s commercial loan portfolio which consists of commercial and industrial, commercial real estate and construction loans. Loans are graded on a scale of 1 to 9. Grades 1 - 5 are pass credits, grade 6 is special mention, grade 7 is substandard, grade 8 is doubtful and grade 9 is loss. A description of the risk grades are as follows: Grade 6 - Special Mention Special mention assets have potential weaknesses that may, if not checked or corrected, weaken the asset or inadequately protect the Company’s position at some future date. These assets pose elevated risk, but their weakness does not yet justify a substandard classification. Borrowers may be experiencing adverse operating trends (declining revenues or margins) or an ill proportioned balance sheet (e.g., increasing inventory without an increase in sales, high leverage, tight liquidity). Adverse economic or market conditions, such as interest rate increases or the entry of a new competitor, may also support a special mention rating. Nonfinancial reasons for rating a credit exposure special mention include management problems, pending litigation, an ineffective loan agreement or other material structural weakness, and any other significant deviation from prudent lending practices. The special mention rating is designed to identify a specific level of risk and concern about asset quality . Although a special mention asset has a higher probability of default than a pass asset, its default is not imminent. Grade 7 - Substandard A ‘‘substandard’’ extension of credit is inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged, if any. Extensions of credit so classified should have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. Loss potential, while existing in the aggregate amount of substandard credits, does not have to exist in individual extensions of credit classified as substandard. Substandard assets have a high probability of payment default, or they have other well-defined weaknesses. They require supervision that is more intensive by Company management. Substandard assets are generally characterized by current or expected unprofitable operations, inadequate debt service coverage, inadequate liquidity, or marginal capitalization. Repayment may depend on collateral or other credit risk mitigation. Grade 8 - Doubtful An extension of credit classified ‘‘doubtful’’ has all the weaknesses inherent in one classified substandard, with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. The possibility of loss is extremely high, but because of certain important and reasonably specific pending factors that may work to the advantage of and strengthen the credit, its classification as an estimated loss is deferred until its more exact status may be determined. Pending factors may include a proposed merger or acquisition, liquidation proceedings, capital injection, perfecting liens on additional collateral, or refinancing plans. Generally, the doubtful classification should not extend for a long period of time because in most cases the pending factors or events that warranted the doubtful classification should be resolved either positively or negatively in a reasonable period of time. Grade 9 - Loss Extensions of credit classified ‘‘loss’’ are considered uncollectible and of such little value that their continuance as bankable assets is not warranted. This classification does not mean that the credit has absolutely no recovery or salvage value, but rather that it is not practical or desirable to defer writing off this basically worthless asset even though partial recovery may be affected in the future. Amounts classified loss should be promptly charged off. The Company will not attempt long term recoveries while the credit remains on the Company’s books. Losses should be taken in the period in which they surface as uncollectible. With loss assets, the underlying borrowers are often in bankruptcy, have formally suspended debt repayments, or have otherwise ceased normal business operations. Once an asset is classified loss, there is little prospect of collecting either its principal or interest. Loans not falling in the criteria above are considered to be pass-rated loans. Non-commercial purpose loans are initially assigned a default loan grade of 99 (Pass) and are risk graded (Grade 6, 7, or 8) according to delinquency status when applicable. The following table provides the risk category of loans by applicable class of loans including purchase credit impaired (“PCI”) loans as of September 30, 2021 and December 31, 2020: Pass Special Substandard Total September 30, 2021 Loans excluding PCI Commercial, Industrial and Agricultural $ 448,003 $ 1,077 $ 1,573 $ 450,653 1-4 Family Residential Real Estate 308,977 1 1,234 310,212 1-4 Family HELOC 100,529 — 352 100,881 Multi-family and Commercial Real Estate 867,351 257 5,144 872,752 Construction, Land Development and Farmland 415,235 — 1,304 416,539 Consumer 232,185 1 1,747 233,933 Other 5,298 — — 5,298 Total loans excluding PCI $ 2,377,578 $ 1,336 $ 11,354 $ 2,390,268 Total PCI loans $ 1,031 $ — $ 1,716 $ 2,747 Total loans $ 2,378,609 $ 1,336 $ 13,070 $ 2,393,015 Pass Special Substandard Total December 31, 2020 Loans excluding PCI Commercial, Industrial and Agricultural $ 456,170 $ 1,519 $ 1,863 $ 459,552 1-4 Family Residential Real Estate 320,555 5 2,165 322,725 1-4 Family HELOC 100,391 — 120 100,511 Multi-family and Commercial Real Estate 829,353 653 3,337 833,343 Construction, Land Development and Farmland 358,606 — 5,676 364,282 Consumer 211,305 7 1,346 212,658 Other 7,150 1,519 — 8,669 Total loans excluding PCI $ 2,283,530 $ 3,703 $ 14,507 $ 2,301,740 Total PCI loans $ 998 $ — $ 2,589 $ 3,587 Total loans $ 2,284,528 $ 3,703 $ 17,096 $ 2,305,327 None of the Company's loans had a risk rating of "Doubtful" or "Loss" as of September 30, 2021 or December 31, 2020. Activity in the Allowance for Loan Loss (“ALL”) by portfolio segment was as follows for the three and nine months ended September 30, 2021 and 2020: Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total Beginning balance at June 30, 2021 $ 6,614 $ 1,923 $ 610 $ 8,498 $ 2,011 $ 1,222 $ 16 $ 20,894 Charge-offs (3) (42) — — — (150) — (195) Recoveries 14 58 2 42 1 81 — 198 Provision 362 (642) (2) 66 78 143 (5) — Ending balance at September 30, 2021 $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Beginning balance at June 30, 2020 $ 4,675 $ 1,454 $ 975 $ 8,407 $ 2,126 $ 584 $ 16 $ 18,237 Charge-offs — (8) — — — (60) — (68) Recoveries 88 22 12 9 4 30 — 165 Provision 249 821 498 (169) (175) 272 4 1,500 Ending balance at September 30, 2020 $ 5,012 $ 2,289 $ 1,485 $ 8,247 $ 1,955 $ 826 $ 20 $ 19,834 Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total Beginning balance at December 31, 2020 $ 5,441 $ 2,445 $ 1,416 $ 8,535 $ 1,841 $ 928 $ 30 $ 20,636 Charge-offs (35) (63) — — — (604) — (702) Recoveries 315 154 7 257 92 138 — 963 Provision 1,266 (1,239) (813) (186) 157 834 (19) — Ending balance at September 30, 2021 $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Beginning balance at December 31, 2019 $ 2,529 $ 1,280 $ 624 $ 5,285 $ 2,649 $ 177 $ 34 $ 12,578 Charge-offs (507) (68) (98) — (114) (355) — (1,142) Recoveries 126 769 15 20 8 60 — 998 Provision 2,864 308 944 2,942 (588) 944 (14) 7,400 Ending balance at September 30, 2020 $ 5,012 $ 2,289 $ 1,485 $ 8,247 $ 1,955 $ 826 $ 20 $ 19,834 The ALL and the recorded investment in loans by portfolio segment and based on impairment method as of was as follows: Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total September 30, 2021 Allowance for loan losses Individually evaluated for impairment $ 847 $ — $ — $ — $ 67 $ 4 $ — $ 918 Acquired with credit impairment — — — — — — — — Collectively evaluated for impairment 6,140 1,297 610 8,606 2,023 1,292 11 19,979 Total $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Loans Individually evaluated for impairment $ 1,433 $ 1,371 $ 352 $ 5,390 $ 1,750 $ 1,747 $ — $ 12,043 Acquired with credit impairment 57 643 14 513 719 801 — 2,747 Collectively evaluated for impairment 449,220 308,841 100,529 867,362 414,789 232,186 5,298 2,378,225 Total $ 450,710 $ 310,855 $ 100,895 $ 873,265 $ 417,258 $ 234,734 $ 5,298 $ 2,393,015 Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total December 31, 2020 Allowance for loan losses Individually evaluated for impairment $ 717 $ 18 $ — $ — $ — $ 13 $ — $ 748 Acquired with credit impairment — — — — — — — — Collectively evaluated for impairment 4,724 2,427 1,416 8,535 1,841 915 30 19,888 Total $ 5,441 $ 2,445 $ 1,416 $ 8,535 $ 1,841 $ 928 $ 30 $ 20,636 Loans Individually evaluated for impairment $ 1,027 $ 1,829 $ 110 $ 2,504 $ 5,676 $ 1,177 $ — $ 12,323 Acquired with credit impairment 187 748 14 657 776 1,205 — 3,587 Collectively evaluated for impairment 458,525 320,896 100,401 830,839 358,606 211,481 8,669 2,289,417 Total $ 459,739 $ 323,473 $ 100,525 $ 834,000 $ 365,058 $ 213,863 $ 8,669 $ 2,305,327 The following tables provide the period-end amounts of loans that are past due thirty to eighty-nine days, past due ninety or more days and still accruing interest, loans not accruing interest, purchased credit impaired loans, and loans current on payments accruing interest by category at September 30, 2021 and December 31, 2020: Current and Accruing 30-89 Days Past Due 90+ Days Nonaccrual Loans Total Loans September 30, 2021 Loans excluding PCI Commercial, Industrial and Agricultural $ 450,349 $ 19 $ — $ 285 $ 450,653 1-4 Family Residential Real Estate 308,897 503 — 812 310,212 1-4 Family HELOC 100,777 — — 104 100,881 Multi-family and Commercial Real Estate 871,921 — — 831 872,752 Construction, Land Development and Farmland 415,350 144 — 1,045 416,539 Consumer 231,504 1,347 5 1,077 233,933 Other 5,298 — — — 5,298 Total loans excluding PCI $ 2,384,096 $ 2,013 $ 5 $ 4,154 $ 2,390,268 Total PCI loans $ 1,580 $ 24 $ — $ 1,143 $ 2,747 Total loans $ 2,385,676 $ 2,037 $ 5 $ 5,297 $ 2,393,015 Current and Accruing 30-89 Days Past Due 90+ Days Nonaccrual Loans Total Loans December 31, 2020 Loans excluding PCI Commercial, Industrial and Agricultural $ 458,974 $ 126 $ — $ 452 $ 459,552 1-4 Family Residential Real Estate 319,180 2,071 — 1,474 322,725 1-4 Family HELOC 100,501 10 — — 100,511 Multi-family and Commercial Real Estate 832,697 150 — 496 833,343 Construction, Land Development and Farmland 363,376 — — 906 364,282 Consumer 210,552 1,413 1 692 212,658 Other 8,669 — — — 8,669 Total loans excluding PCI $ 2,293,949 $ 3,770 $ 1 $ 4,020 $ 2,301,740 Total PCI loans $ 1,584 $ 37 $ — $ 1,966 $ 3,587 Total loans $ 2,295,533 $ 3,807 $ 1 $ 5,986 $ 2,305,327 Approximately $1,973 and $2,438 of nonaccrual loans as of September 30, 2021 and December 31, 2020, respectively, were performing pursuant to their contractual terms at those dates. Mortgage loans held for sale are excluded from the loan tables herein and have $977 and $630 on nonaccrual as of September 30, 2021 and December 31, 2020, respectively. Purchased Credit Impaired Loans The Company has purchased loans, for which there was, at acquisition, evidence of deterioration of credit quality since origination and it was probable, at acquisition that all contractually required payments would not be collected. The carrying amount of those loans is as follows: September 30, 2021 December 31, 2020 Commercial, Industrial and Agricultural $ 782 $ 919 1-4 Family Residential Real Estate 868 1,004 1-4 Family HELOC 19 19 Multi-family and Commercial Real Estate 1,175 1,325 Construction, Land Development and Farmland 935 992 Consumer 1,426 1,924 Total outstanding balance 5,205 6,183 Less remaining purchase discount 2,458 2,596 Allowance for loan losses — — Carrying amount, net of allowance for loan losses and remaining purchase discounts $ 2,747 $ 3,587 Accretable yield, or income expected to be collected on PCI loans, is as follows: 2021 2020 Balance at January 1, $ 580 $ 98 New loans purchased — 870 Accretion income (52) (137) Balance at September 30, $ 528 $ 831 On January 1, 2020 and April 1, 2020, the Company completed the TCB Holdings and FABK Transactions, respectively (see Note 11 for more information). As a result of the acquisitions, the Company recorded loans with an initial fair value of $170.0 million and $625.8 million, respectively. Of those loans, $1,688 and $4,668, respectively, were considered to be PCI loans, which are loans for which it is probable at the acquisition date that all contractually required payments will not be collected. The remaining loans are considered to be purchased non-impaired loans and their related fair value discount or premium is recognized as an adjustment to yield over the remaining life of each loan. PCI loans purchased during the year ended December 31, 2020, for which it was probable at acquisition that all contractually required payments would not be collected are as follows: Tennessee Community Bank Holdings, Inc. acquisition on January 1, 2020 First Advantage Bancorp acquisition on April 1, 2020 Contractually required payments receivable of loans purchased during the year: $ 2,799 $ 7,540 Nonaccretable difference (980) (2,133) Cash flows expected to be collected at acquisition $ 1,819 $ 5,407 Accretable yield (131) (739) Fair value of acquired loans at acquisition $ 1,688 $ 4,668 Impaired Loans Individually impaired loans by class of loans were as follows at September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Unpaid Recorded Investment Related Unpaid Recorded Investment Related With no related allowance recorded Commercial, Industrial and Agricultural $ 1,691 $ 642 $ — $ 1,400 $ 367 $ — 1-4 Family Residential Real Estate 2,419 2,015 — 3,034 2,473 — 1-4 Family HELOC 378 366 — 130 124 — Multi-family and Commercial Real Estate 7,141 5,903 — 4,549 3,161 — Construction, Land Development and Farmland 2,617 2,210 — 6,809 6,452 — Consumer 3,848 2,512 — 3,590 2,348 — Subtotal $ 18,094 $ 13,648 $ — $ 19,512 $ 14,925 $ — With an allowance recorded Commercial, Industrial and Agricultural $ 859 $ 847 $ 847 $ 859 $ 847 $ 717 1-4 Family Residential Real Estate — — — 104 104 18 1-4 Family HELOC — — — — — — Multi-family and Commercial Real Estate — — — — — — Construction, Land Development and Farmland 259 259 67 — — — Consumer 39 36 4 34 34 13 Subtotal 1,157 1,142 918 997 985 748 Total $ 19,251 $ 14,790 $ 918 $ 20,509 $ 15,910 $ 748 The average recorded investment in impaired loans for the three and nine months ended September 30, 2021, and 2020 was as follows: Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average recorded investment Interest income recognized Average recorded investment Interest income recognized With no allowance Commercial, Industrial and Agricultural $ 444 $ 6 $ 594 $ 42 $ 355 $ 26 $ 354 $ 56 1-4 Family Residential Real Estate 2,044 31 3,002 54 2,296 109 2,631 154 1-4 Family HELOC 332 3 331 — 272 11 367 — Multi-family and Commercial Real Estate 5,655 86 4,375 63 4,741 271 4,138 278 Construction, Land Development and Farmland 4,222 42 2,949 28 5,424 114 2,471 115 Consumer 2,473 83 2,118 68 2,411 275 1,076 205 Subtotal $ 15,170 $ 251 $ 13,369 $ 255 $ 15,499 $ 806 $ 11,037 $ 808 Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average recorded investment Interest income recognized Average recorded investment Interest income recognized With an allowance recorded Commercial, Industrial and Agricultural $ 847 $ 6 $ 947 $ 6 $ 847 $ 18 $ 976 $ 32 1-4 Family Residential Real Estate — — — — 26 — — — 1-4 Family HELOC — — — — — — — — Multi-family and Commercial Real Estate 50 — — — 38 — — — Construction, Land Development and Farmland 86 3 — — 65 4 43 — Consumer 46 1 — — 43 2 1 — Subtotal $ 1,029 $ 10 $ 947 $ 6 $ 1,019 $ 24 $ 1,020 $ 32 Total $ 16,199 $ 261 $ 14,316 $ 261 $ 16,518 $ 830 $ 12,057 $ 840 Restructured Loans As of September 30, 2021 and December 31, 2020, the Company had recorded investments in troubled debt restructurings (“TDRs”) of $2,903 and $4,236, respectively. The Company did not allocate a specific allowance for those loans at September 30, 2021 and December 31, 2020 and there were no commitments to lend additional amounts. Loans accounted for as TDR include modifications from original terms such as those due to bankruptcy proceedings, certain modifications of amortization periods or extended suspension of principal payments due to customer financial difficulties. In order to determine whether a borrower is experiencing financial difficulty, an evaluation is performed of the probability that the borrower will be in payment default on any of its debt in the foreseeable future without the modification. Loans accounted for as TDR are individually evaluated for impairment. There were no TDR modifications in the three and nine months ending September 30, 2021 or the three months ended September 30, 2020. Modifications made during the nine months ended September 30, 2020 are displayed below. Number of Contracts Pre-Modification Outstanding Recorded Investments Post-Modification Outstanding Recorded Investments Commercial, Industrial and Agricultural 1 $ 150 $ 150 1-4 Family Residential 1 721 721 Multi-family and Commercial Real Estate 1 394 394 Total 3 $ 1,265 $ 1,265 Programs as part of COVID-19 Relief The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”), which was signed into law in March 2020 and subsequently amended, along with subsequent regulatory guidance encouraged financial institutions to work prudently with borrowers who are or may be unable to meet their contractual payment obligations due to the effects of COVID-19. Additionally, the CARES Act further provides that a qualified loan modification is exempt by law from classification as a TDR as defined by U.S. GAAP beginning March 1, 2020 until the earlier of January 1, 2022 or the date that is 60 days after the date on which the national emergency concerning the COVID-19 outbreak terminates. The following table outlines the Company's recorded investment and percentage of loans held for investment by class of financing receivable for Company executed deferrals that remain on deferral at September 30, 2021, in connection with Company COVID-19 relief programs. These remaining deferrals typically modify the loans such that they are interest-only for a period of time and were not considered TDRs under the interagency regulatory guidance or the CARES Act. September 30, 2021 Active Deferrals % of Loans Multi-family and Commercial $ 67,372 2.82 % The CARES Act provides over $2.0 trillion in emergency economic relief to individuals and businesses impacted by the COVID-19 pandemic. The CARES Act authorized the Small Business Administration (“SBA”) to administer new loan programs including, but not limited to, the guarantee of loans under a new 7(a) loan program called the Paycheck Protection Program (“PPP”). As of September 30, 2021, the Company had 7 PPP loans outstanding amounting to $292 which are included in the commercial, industrial, and agricultural segment. PPP loans do not have a corresponding allowance as they are fully guaranteed by the SBA. Fees range from 1% to 5% of the loan and are deferred and amortized over the life of the loan. As PPP loans are forgiven, any deferred loan fee or cost is recognized related to each individual loan. As of September 30, 2021, $83,075 in PPP loans had cumulatively been forgiven of the $83,366 in loan originations since the CARES Act’s inception. Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Interest $ 19 $ 210 $ 216 $ 358 Fees 176 455 1,808 739 Total PPP Income $ 195 $ 665 $ 2,024 $ 1,097

Derivatives

Derivatives	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES	DERIVATIVES The Company utilizes interest rate swap agreements as part of its asset liability management strategy to help manage its interest rate risk position. The notional amount of the interest rate swaps does not represent amounts exchanged by the parties. The amount exchanged is determined by reference to the notional amount and other terms of the individual interest rate swap agreements. Interest Rate Swaps Designated as Cash Flow Hedges Interest rate swaps with notional amounts totaling $10,000 as of September 30, 2021 were designated as cash flow hedges of certain variable rate subordinated debentures, which are fully effective. As such, no amount of ineffectiveness has been included in net income. Therefore, the aggregate fair value of the swaps is recorded in other assets (liabilities) with changes in fair value recorded in other comprehensive income (loss). The amount included in accumulated other comprehensive income (loss) would be reclassified to current earnings should the hedges no longer be considered effective. The Company expects the hedges to remain fully effective during the remaining terms of the swap agreements. Losses of $2,290 and $5,149 were reclassified from accumulated other comprehensive income into net income related to the $100 million and $150 million in swaps which were terminated during the three and nine months ended September 30, 2021, respectively. Summary information related to the interest rate swaps designated as cash flow hedges as of September 30, 2021, is as follows: Notional amounts $ 10,000 Weighted average pay rates 5.19 % Weighted average receive rates 2.38 % Weighted average maturity 1.71 years Unrealized losses $ 468 The following table reflects the cash flow hedges included in the Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 December 31, 2020 Notional Amount Fair Value Notional Amount Fair Value Included in other liabilities: Interest rate swaps related to: Subordinated debentures $ 10,000 $ (468) $ 10,000 $ (690) Short-term interest-bearing liabilities — — 150,000 (6,967) Total included in other liabilities $ 10,000 $ (468) $ 160,000 $ (7,657) The following table presents the net gains (losses) recorded in accumulated other comprehensive income net of tax, relating to the cash flow derivative instruments for the three and nine months ended September 30, 2021 and 2020, respectively: Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Interest rate swaps - subordinate debentures $ 47 $ 51 $ 164 $ (230) Interest rate swaps - interest-bearing liabilities 1,562 324 5,146 (4,532) $ 1,609 $ 375 $ 5,310 $ (4,762) Fair Value Hedges Summary information related to the fair value hedges as of September 30, 2021, is as follows: Notional amounts $ 17,090 Weighted average pay rates 3.68 % Weighted average receive rates 1.10 % Weighted average maturity 7.44 years Unrealized losses $ 848 The following table reflects the fair value hedges included in the Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 December 31, 2020 Notional Amount Fair Value Notional Amount Fair Value Included in other liabilities: Interest rate swaps related to investments 17,090 (848) 18,525 (1,495) Total included in other liabilities $ 17,090 $ (848) $ 18,525 $ (1,495) The following table reflects the fair value hedges and the underlying hedged items included in the Consolidated Statements of Income for the three and nine months ended September 30, 2021 and 2020, respectively: Three months ended September 30, Nine months ended September 30, Item Location 2021 2020 2021 2020 Interest rate swaps - securities Interest on investment securities, nontaxable $ (118) $ (118) $ (356) $ (243) Hedged item - securities Interest on investment securities, nontaxable $ 118 $ 118 $ 356 $ 243

Stock-based Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION In 2006, the board of directors and shareholders of the Bank (then known as "Commerce Union Bank") approved the Commerce Union Bank Stock Option Plan (the “Plan”). The Plan provided for the granting of stock options for up to 625,000 shares of Bank common stock to employees and organizers and authorized the issuance of Bank common stock upon the exercise of such options. As part of the Bank's reorganization into a holding company corporate structure in 2012, all Bank options were replaced with Commerce Union Bancshares, Inc. (now known as "Reliant Bancorp, Inc.") options with no change in terms. On March 10, 2015, the shareholders of Reliant Bancorp (then known as "Commerce Union Bancshares, Inc.") approved the Commerce Union Bancshares, Inc. Amended and Restated Stock Option Plan (the “A&R Plan”), which permits the grant of awards with respect to up to 1,250,000 shares of Reliant Bancorp common stock in the form of stock options. As part of the merger of Commerce Union Bank and Reliant Bank in 2015, all outstanding stock options of Reliant Bank were converted to stock options of Reliant Bancorp (then known as "Commerce Union Bancshares, Inc.") under the A&R Plan. Under the A&R Plan, stock option awards may be granted in the form of incentive stock options or non-statutory stock options, and are generally exercisable for up to 10 years following the date such option awards are granted. Exercise prices of incentive stock options must be equal to or greater than the fair market value of Reliant Bancorp's common stock on the grant date. On June 18, 2015, the shareholders of Reliant Bancorp (then known as "Commerce Union Bancshares, Inc.") approved the Commerce Union Bancshares, Inc. 2015 Equity Incentive Plan, which reserves up to 900,000 shares of Reliant Bancorp common stock to be subject to awards under the plan, including awards in the form of stock options, restricted stock grants, performance-based awards, and other awards denominated or payable by reference to or based on or related to Reliant Bancorp common stock. The Company has recognized stock-based compensation expense, within salaries and employee benefits for employees, and within other non-interest expense for directors, in the consolidated statement of income as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Stock-based compensation expense before income taxes $ 458 $ 349 $ 1,265 $ 1,183 Less: deferred tax benefit (120) (91) (331) (309) Reduction of net income $ 338 $ 258 $ 934 $ 874 Common Stock Options A summary of stock option activity for the nine months ended September 30, 2021 is as follows: Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at December 31, 2020 116,621 $ 18.97 5.87 years $ 304 Granted — $ — Exercised (1,702) $ 14.36 20 Forfeited or expired (5,600) $ 13.42 Outstanding at September 30, 2021 109,319 $ 19.33 5.32 years $ 1,340 Exercisable at September 30, 2021 86,519 $ 17.88 4.81 years $ 1,186 As of September 30, 2021, there was $144 of unrecognized future compensation expense to be recognized related to stock options. The cost is expected to be recognized over a weighted-average period of 2.31 years. Restricted Stock and Restricted Stock Unit Awards The following table shows the activity related to non-vested restricted stock and restricted stock unit awards for the nine months ended September 30, 2021: Restricted Stock Units Restricted Stock Underlying Shares Weighted Average Grant-Date Shares Weighted Average Grant-Date Outstanding at January 1, 2021 132,650 $ 16.93 40,910 $ 26.82 Granted 70,655 26.07 — — Vested (14,400) 14.81 (35,410) 27.54 Forfeited (9,500) 17.59 — — Outstanding at September 30, 2021 179,405 $ 20.67 5,500 $ 22.17 As of September 30, 2021, there was $2,297 and $23 of unrecognized compensation cost related to non-vested restricted stock units and restricted stock units, respectively. The cost is expected to be recognized over a weighted-average period of 2.01 years for the restricted stock units and 0.62 years for the restricted stock share awards. The total fair value of shares vested during nine months ended September 30, 2021 was $1,379.

Regulatory Capital Requirements

Regulatory Capital Requirements	9 Months Ended
	Sep. 30, 2021
Banking and Thrift, Other Disclosures [Abstract]
REGULATORY CAPITAL REQUIREMENTS	REGULATORY CAPITAL REQUIREMENTS The Company and the Bank are subject to regulatory capital requirements administered by the federal and state banking agencies. Capital adequacy guidelines and, additionally for banks, prompt corrective action regulations, involve quantitative measures of assets, liabilities, and certain off-balance-sheet items calculated under regulatory accounting practices. Capital amounts and classifications are also subject to qualitative judgments by regulators. Failure to meet capital requirements can initiate regulatory action or affect the amount of dividends the Company and the Bank may distribute. Management believes that as of September 30, 2021, the Company and the Bank met all capital adequacy requirements to which they were subject. Capital amounts and ratios for Reliant Bancorp and the Bank are presented below as of September 30, 2021 and December 31, 2020. Actual Minimum Required To Be Well Amount Ratio Amount Ratio Amount Ratio September 30, 2021 Reliant Bancorp Tier I leverage $ 297,367 10.04 % $ 118,473 4.00 % $ 148,091 5.00 % Common equity tier I 285,537 10.52 % 189,996 7.00 % 176,425 6.50 % Tier I risk-based capital 297,367 10.95 % 230,833 8.50 % 217,254 8.00 % Total risk-based capital 377,977 13.92 % 285,112 10.50 % 271,535 10.00 % Bank Tier I leverage $ 347,450 11.76 % $ 118,185 4.00 % $ 147,732 5.00 % Common equity tier I 347,450 14.10 % 172,493 7.00 % 160,172 6.50 % Tier I risk-based capital 347,450 14.10 % 209,456 8.50 % 197,135 8.00 % Total risk-based capital 369,072 14.98 % 258,695 10.50 % 246,377 10.00 % Actual Minimum Required To Be Well December 31, 2020 Reliant Bancorp Tier I leverage $ 262,282 8.91 % $ 117,747 4.00 % $ 147,184 5.00 % Common equity tier I 250,513 10.22 % 171,584 7.00 % 159,328 6.50 % Tier I risk-based capital 262,282 10.70 % 208,355 8.50 % 196,099 8.00 % Total risk-based capital 342,246 13.96 % 257,420 10.50 % 245,162 10.00 % Bank Tier I leverage $ 313,633 10.64 % $ 117,907 4.00 % $ 147,384 5.00 % Common equity tier I 313,633 12.83 % 171,117 7.00 % 158,894 6.50 % Tier I risk-based capital 313,633 12.83 % 207,785 8.50 % 195,562 8.00 % Total risk-based capital 334,919 13.71 % 256,503 10.50 % 244,288 10.00 %

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE The following is a summary of the components comprising basic and diluted earnings per common share of stock ("EPS"): Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Basic EPS Computation Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 19,186 Weighted average common shares outstanding 16,665,155 16,587,274 16,632,587 15,053,087 Basic earnings per common share $ 0.80 $ 0.70 $ 2.31 $ 1.27 Diluted EPS Computation Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 19,186 Weighted average common shares outstanding 16,665,155 16,587,274 16,632,587 15,053,087 Dilutive effect of stock options, restricted stock shares and units, and employee stock purchase plan 140,002 62,399 144,385 67,616 Adjusted weighted average common shares outstanding 16,805,157 16,649,673 16,776,972 15,120,703 Diluted earnings per common share $ 0.79 $ 0.69 $ 2.29 $ 1.27

Fair Values of Assets and Liabi

Fair Values of Assets and Liabilities	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
FAIR VALUES OF ASSETS AND LIABILITIES	FAIR VALUES OF ASSETS AND LIABILITIES Financial accounting standards relating to fair value measurements establish a framework for measuring fair value. That framework provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: Level 1 Inputs to the valuation methodology are unadjusted quoted prices for identical assets or liabilities in active markets that the Company has the ability to access. Level 2 Inputs to the valuation methodology include: • Quoted prices for similar assets or liabilities in active markets; • Quoted prices for identical or similar assets or liabilities in inactive markets; • Inputs other than quoted prices that are observable for the asset or liability; and • Inputs that are derived principally from or corroborated by the observable market data by correlation or other means. If the asset or liability has a specified (contractual) term, the Level 2 input must be observable for substantially the full term of the asset or liability. Level 3 Inputs to the valuation methodology are unobservable and reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. An asset’s or liability’s fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques should maximize the use of observable inputs and minimize the use of unobservable inputs. Following is a description of the valuation methodologies used for assets and liabilities measured at fair value on a recurring basis: Securities available for sale: The fair values of securities available for sale are determined by obtaining quoted prices on nationally recognized securities exchanges (Level 1 inputs) or matrix pricing, which is a mathematical technique widely used in the industry to value debt securities without relying exclusively on quoted prices for the specific securities but rather by relying on the securities’ relationship to other benchmark quoted securities (Level 2 inputs). The Company obtains fair value measurements for securities available for sale from an independent pricing service. The fair value measurements consider observable data that may include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, cash flows and reference data, including market research publications, among other things. Interest rate swaps: The fair values of interest rate swaps and fair value hedges are determined based on estimated discounted future cash flows. Certain assets and liabilities are measured at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). Assets and liabilities measured at fair value on a nonrecurring basis include the following: Impaired Loans : The fair value of an impaired loan with specific allocations of the allowance for loan losses is generally based on the present value of expected payments using the loan’s effective rate as the discount rate or recent real estate appraisals. These appraisals may utilize a single valuation approach or a combination of approaches including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the appraisers to adjust for differences between the comparable sales and income data available. Such adjustments are typically significant and result in a Level 3 classification of the inputs for determining fair value. Other Real Estate and Repossessed Assets : The fair value of other real estate and repossessed assets is generally based on recent appraisals less estimated disposition cost. These appraisals may use a single valuation approach or a combination of approaches including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the appraisers to adjust for differences between the comparable sales and income data available. Such adjustments are typically significant and result in Level 3 classification of the inputs for determining fair value. The methods described above may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Company’s valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. Fair value estimates involve uncertainties and matters of significant judgment regarding interest rates, credit risk, prepayments, and other factors, especially in the absence of broad markets for particular items. Changes in assumptions or in market conditions could significantly affect the estimates. The following table sets forth the Company’s major categories of assets and liabilities measured at fair value on a recurring basis, by level within the fair value hierarchy, as of September 30, 2021 and December 31, 2020: Fair Value Quoted Significant Significant September 30, 2021 Assets U. S. Treasury and other U. S. government agencies $ 218 $ — $ 218 $ — State and municipal 170,971 — 170,971 — Corporate bonds 28,152 — 28,152 — Mortgage-backed securities 52,823 — 52,823 — Asset-backed securities 2,252 — 2,252 — Liabilities Derivative liabilities $ 1,316 $ — $ 1,316 $ — December 31, 2020 Assets U. S. Treasury and other U. S. government agencies $ 48 $ — $ 48 $ — State and municipal 200,988 — 200,988 — Corporate bonds 24,113 — 24,113 — Mortgage-backed securities 28,442 — 28,442 — Asset-backed securities 3,062 — 3,062 — Liabilities Derivative liabilities $ 9,152 $ — $ 9,152 $ — The following table sets forth the Company’s major categories of assets and liabilities measured at fair value on a nonrecurring basis, by level within the fair value hierarchy, as of September 30, 2021 and December 31, 2020: Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs September 30, 2021 Assets Impaired loans $ 13,872 $ — $ — $ 13,872 Other real estate 3,088 — — 3,088 Other repossessions 865 — — 865 December 31, 2020 Assets Impaired loans $ 15,162 $ — $ — $ 15,162 Other real estate 1,246 — — 1,246 Other repossessions 1,424 — — 1,424 The following table presents additional quantitative information about assets measured at fair value on a nonrecurring basis and for which we have utilized Level 3 inputs to determine fair value at September 30, 2021 and December 31, 2020: Valuation Significant Range Impaired loans Appraisal Estimated costs to sell 10% Other real estate Appraisal Estimated costs to sell 10% Other repossessions Third-party guidelines Estimated costs to sell 10% (1) The fair value is generally determined through independent appraisals of the underlying collateral, which may include Level 3 inputs that are not identifiable, or by using the discounted cash flow method if the loan is not collateral dependent. Estimated cash flows change and appraised values of the assets or collateral underlying the loans will be sensitive to changes. Carrying amounts and estimated fair values of financial instruments not reported at fair value at September 30, 2021 and December 31, 2020 were as follows: September 30, 2021 Carrying Estimated Quoted Prices in Significant Significant Financial assets Cash and due from banks $ 13,270 $ 13,270 $ 13,270 $ — $ — Interest-bearing deposits in financial institutions 66,155 66,155 66,155 — — Federal funds sold 1,002 1,002 — 1,002 — Loans, net 2,368,936 2,393,109 — — 2,393,109 Mortgage loans held for sale 62,543 62,521 — 62,521 — Accrued interest receivable 14,374 14,374 — 14,374 — Restricted equity securities 15,770 15,770 — 15,770 — Financial liabilities Deposits $ 2,547,705 $ 2,548,511 $ — $ — $ 2,548,511 Accrued interest payable 2,302 2,302 — 2,302 — Subordinate debentures 70,821 72,373 — — 72,373 Federal Home Loan Bank advances — — — — — December 31, 2020 Carrying Estimated Quoted Prices in Significant Significant Financial assets Cash and due from banks $ 13,717 $ 13,717 $ 13,717 $ — $ — Interest-bearing deposits in financial institutions 79,756 79,756 79,756 — — Federal funds sold 1,572 1,572 — 1,572 — Loans, net 2,280,147 2,293,723 — — 2,293,723 Mortgage loans held for sale 147,524 149,342 — 149,342 — Accrued interest receivable 14,889 14,889 — 14,889 — Restricted equity securities 16,551 16,551 — 16,551 — Financial liabilities Deposits $ 2,579,235 $ 2,583,525 $ — $ — $ 2,583,525 Accrued interest payable 2,571 2,571 — 2,571 — Subordinate debentures 70,446 71,750 — — 71,750 Federal Home Loan Bank advances 10,000 10,000 — — 10,000 The methods and assumptions used to estimate fair value are described as follows: Carrying amount is the estimated fair value for cash and cash equivalents, accrued interest receivable and payable, restricted equity securities, federal funds sold or purchased, demand deposits, and variable rate loans or deposits that re-price frequently and fully. For fixed rate loans or deposits and for variable rate loans or deposits with infrequent re-pricing or re-pricing limits, fair value is based on discounted cash flows using current market rates applied to the estimated life and credit risk. Fair value of debt is based on discounted cash flows using current rates for similar financing.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
SEGMENT REPORTING	SEGMENT REPORTING The Company has two reportable business segments: commercial banking and residential mortgage banking. Segment information is derived from the internal reporting system utilized by management. Revenues and expenses for segments reflect those which can be specifically identified and have been assigned based on internally developed allocation methods. Financial results have been presented, to the extent practicable, as if each segment operated on a stand-alone basis. Commercial Banking provides deposit and lending services to consumer and business customers within our primary geographic markets. Our customers are serviced through branch locations, ATMs, online banking, and mobile banking. Residential Mortgage Banking originates traditional first lien residential mortgage loans and first lien home equity lines of credit throughout the United States. The traditional first lien residential mortgage loans are typically underwritten to government agency standards and sold to third-party secondary market mortgage investors. The home equity lines of credit are typically sold to participating banks or other investor groups and are underwritten to their standards. RMV also acquires loans from approved correspondent lenders and resells them in the secondary market. These loans are not government agency-qualified loans and are of higher risk, such as jumbo loans or senior position home equity lines of credit. The following presents summarized results of operations for the Company’s business segments for the periods indicated: Three Months Ended Commercial Banking Residential Elimination Consolidated Net interest income $ 28,164 $ 835 $ — $ 28,999 Provision for loan losses — — — — Noninterest income 6,651 4,177 41 10,869 Noninterest expense (excluding merger expense) 16,551 4,377 — 20,928 Merger expense 1,453 — — 1,453 Income tax expense 3,522 29 — 3,551 Net income 13,289 606 41 13,936 Noncontrolling interest in net income of subsidiary — (606) (41) (647) Net income attributable to common shareholders $ 13,289 $ — $ — $ 13,289 Three Months Ended Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 29,731 $ 808 $ — $ 30,539 Provision for loan losses 1,500 — — 1,500 Noninterest income 2,219 3,797 (14) 6,002 Noninterest expense (excluding merger expense) 16,067 4,190 — 20,257 Merger expense 77 — — 77 Income tax (benefit) expense 2,773 27 — 2,800 Net (loss) income 11,533 388 (14) 11,907 Noncontrolling interest in net income of subsidiary — (388) 14 (374) Net income attributable to common shareholders $ 11,533 $ — $ — $ 11,533 Nine months ended September 30, 2021 Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 84,737 $ 2,849 $ — $ 87,586 Provision for loan losses — — — — Noninterest income 14,395 12,461 (340) 26,516 Noninterest expense (excluding merger expense) 49,581 13,495 — 63,076 Merger expense 1,453 — — 1,453 Income tax expense (benefit) 9,615 118 — 9,733 Net income (loss) 38,483 1,697 (340) 39,840 Noncontrolling interest in net income of subsidiary — (1,697) 340 (1,357) Net income attributable to common shareholders $ 38,483 $ — $ — $ 38,483 Nine months ended September 30, 2020 Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 75,933 $ 1,677 $ — $ 77,610 Provision for loan losses 7,400 — — 7,400 Noninterest income 6,102 7,601 3 13,706 Noninterest expense (excluding merger expense) 44,961 10,340 — 55,301 Merger expense 6,895 — — 6,895 Income tax expense (benefit) 3,593 (69) — 3,524 Net income (loss) 19,186 (993) 3 18,196 Noncontrolling interest in net loss of subsidiary — 993 (3) 990 Net income attributable to common shareholders $ 19,186 $ — $ — $ 19,186

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES Income tax expense for the three and nine months ended September 30, 2021 totaled $3,551 and $9,733, respectively, compared to $2,800 and $3,524 for the three and nine months ended September 30, 2020, respectively. The effective tax rate for the three and nine months ended September 30, 2021 was 20.3% and 19.6%, respectively, compared to 19.0% and 16.2% for the three and nine months ended September 30, 2020, respectively.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
BUSINESS COMBINATIONS	BUSINESS COMBINATIONS Tennessee Community Bank Holdings, Inc. Effective January 1, 2020, Reliant Bancorp completed the acquisition of TCB Holdings pursuant to the Agreement and Plan of Merger, dated September 16, 2019 (the “TCB Holdings Agreement”), by and among Reliant Bancorp, TCB Holdings, and Community Bank & Trust, a Tennessee-chartered commercial bank and wholly owned subsidiary of TCB Holdings (“CBT”). On the terms and subject to the conditions set forth in the TCB Holdings Agreement, TCB Holdings merged with and into Reliant Bancorp (the “TCB Holdings Transaction”), with Reliant Bancorp as the surviving corporation. Immediately following the TCB Holdings Transaction, CBT merged with and into the Bank, with the Bank continuing as the surviving banking corporation. Pursuant to the TCB Holdings Agreement, at the effective time of the TCB Holdings Transaction, each outstanding share of TCB Holdings common stock, par value $1.00 per share (other than certain excluded shares), was converted into and canceled in exchange for the right to receive (i) $17.13 in cash, without interest, and (ii) 0.769 shares of the Reliant Bancorp’s common stock, par value $1.00 per share (“Reliant Bancorp Common Stock”). The aggregate consideration payable by Reliant Bancorp in respect of shares of TCB Holdings common stock as consideration for the TCB Holdings Transaction was 811,210 shares of Reliant Bancorp Common Stock and approximately $18,073 in cash. Reliant Bancorp did not issue fractional shares of Reliant Bancorp Common Stock in connection with the TCB Holdings Transaction, but paid cash in lieu of fractional shares based on the volume weighted average closing price per share of the Reliant Bancorp Common Stock on The Nasdaq Capital Market for the 10 consecutive trading days ending on and including December 30, 2019 (calculated as $22.36). At the effective time of the TCB Holdings Transaction, each outstanding option to purchase TCB Holdings common stock was canceled in exchange for a cash payment in an amount equal to the product of (i) $34.25 minus the per share exercise price of the option multiplied by (ii) the number of shares of TCB Holdings common stock subject to the option (to the extent not previously exercised). Reliant Bancorp paid aggregate consideration to holders of unexercised options of approximately $430. All shares of Reliant Bancorp Common Stock outstanding immediately prior to the TCB Holdings Transaction were unaffected by the TCB Holdings Transaction. The following table details the financial impact of the TCB Holdings Transaction, including the calculation of the purchase price, the allocation of the purchase price to the fair values of net assets assumed and goodwill recognized: Calculation of Purchase Price Shares of Tennessee Community Bank Holdings, Inc. common stock outstanding as of January 1, 2020 1,055,041 Exchange ratio for Reliant Bancorp, Inc. common stock 0.769 Reliant Bancorp, Inc. common stock shares issued 811,210 Reliant Bancorp, Inc. share price at January 1, 2020 $ 22.24 Estimated value of Reliant Bancorp, Inc. shares issued 18,041 Cash settlement for Tennessee Community Bank Holdings, Inc. common stock ($17.13 per share) 18,073 Cash settlement for Tennessee Community Bank Holdings, Inc.'s 26,450 outstanding stock options ($34.25 settlement price less weighted average exercise price of $18.00) 430 Cash settlement for Reliant Bancorp, Inc. fractional shares ($22.36 per pro rata fractional share) 3 Estimated fair value of Tennessee Community Bank Holdings, Inc. $ 36,547 Allocation of Purchase Price Total consideration above $ 36,547 Fair value of assets acquired and liabilities assumed Cash and cash equivalents 11,026 Investment securities available for sale 56,336 Loans, net of unearned income 171,445 Accrued interest receivable 948 Premises and equipment 5,221 Cash surrender value of life insurance contracts 5,629 Restricted equity securities 909 Core deposit intangible 3,617 Other assets 833 Deposits (210,538) Deferred tax liability (157) Borrowings (58) FHLB advances (13,102) Other liabilities (4,337) Total fair value of net assets acquired 27,772 Goodwill $ 8,775 CBT was a Tennessee-based full-service community bank with operations in Ashland City, Kingston Springs, Pegram, Pleasant View, and Springfield, Tennessee. These communities lie on the northwest perimeter of Nashville, Tennessee. First Advantage Bancorp Effective April 1, 2020, Reliant Bancorp completed the acquisition of FABK pursuant to the Agreement and Plan of Merger, dated October 22, 2019 (the “FABK Agreement”), by and among Reliant Bancorp, FABK, and PG Merger Sub, Inc., a Tennessee corporation and wholly owned subsidiary of Reliant Bancorp ("Merger Sub"). On the terms and subject to the conditions set forth in the FABK Agreement, Merger Sub merged with and into FABK (the "FABK Transaction"), with FABK as the surviving corporation, followed immediately by the merger of FABK with and into Reliant Bancorp, with Reliant Bancorp as the surviving corporation. Immediately following the merger of FABK into Reliant Bancorp, First Advantage Bank, a Tennessee-chartered commercial bank and wholly owned subsidiary of FABK ("FAB"), merged with and into the Bank, with the Bank continuing as the surviving banking corporation. Pursuant to the FABK Agreement, at the effective time of the FABK Transaction, each outstanding share of FABK common stock, par value $0.01 per share (the “FABK Common Stock”), other than certain excluded shares, was converted into the right to receive (i) 1.17 shares of Reliant Bancorp Common Stock and (ii) $3.00 in cash, without interest. In lieu of the issuance of fractional shares of Reliant Bancorp Common Stock, Reliant Bancorp agreed to pay cash in lieu of fractional shares based on the volume-weighted average closing price per share of Reliant Bancorp Common Stock on The Nasdaq Capital Market for the 10 consecutive trading days ending on and including March 30, 2020 (calculated as $11.74). Based on the April 1, 2020 opening price for Reliant Bancorp Common Stock of $11.27 per share and 3,935,165 shares of FABK Common Stock outstanding on April 1, 2020, the consideration for the FABK Transaction was approximately $64,094, in the aggregate, or $16.28 per share of FABK Common Stock. The following table details the financial impact of the FABK Transaction, including the calculation of the purchase price, the allocation of the purchase price to the fair values of net assets assumed and goodwill recognized: Calculation of Purchase Price Shares of First Advantage Bancorp common stock outstanding as of April 1, 2020 3,935,165 Conversion of restricted stock units to shares of common stock of First Advantage Bancorp as of April 1, 2020 2,000 Total First Advantage Bancorp common stock outstanding as of April 1, 2020 3,937,165 Exchange ratio for Reliant Bancorp, Inc. common stock 1.17 Reliant Bancorp, Inc. common stock shares issued 4,606,483 Remove fractional shares (64) Reliant Bancorp, Inc. common stock shares issued 4,606,419 Reliant Bancorp, Inc. share price at April 1, 2020 $ 11.27 Estimated value of Reliant Bancorp, Inc. shares issued 51,914 Cash settlement for Reliant Bancorp, Inc. fractional shares ($11.74 per pro rata fractional share) 1 Cash settlement for First Advantage Bancorp common stock ($3.00 per share) 11,805 Cash settlement for First Advantage Bancorp restricted stock units ($3.00 per share) 6 Cash settlement for First Advantage Bancorp's 34,800 outstanding stock options ($30.00 settlement price less weighted average exercise price of $19.44) 368 Estimated fair value of First Advantage Bancorp $ 64,094 Allocation of Purchase Price Total consideration above $ 64,094 Fair value of assets acquired and liabilities assumed Cash and cash equivalents 11,159 Investment securities available for sale 35,970 Loans, net of unearned income 622,423 Mortgage loans held for sale, net 5,878 Premises and equipment 7,757 Deferred tax asset 4,937 Cash surrender value of life insurance contracts 14,776 Other real estate and repossessed assets 1,259 Core deposit intangible 2,280 Operating lease right-of-use assets 5,846 Other assets 11,624 Deposits (608,690) Borrowings (35,962) Operating lease liabilities (6,536) Other liabilities (10,606) Total fair value of net assets acquired 62,115 Goodwill $ 1,979 FAB was a Tennessee-based full-service community bank headquartered in Clarksville, Tennessee. FAB operated branch offices in Montgomery, Davidson and Williamson counties, Tennessee and operated a loan production office in Knoxville, Tennessee primarily originating manufactured housing loans. Supplemental Pro Forma Combined Condensed Statements of Income Pro forma data for the three and nine months ended September 30, 2021 and 2020 in the table below presents information as if the TCB Holdings Transaction and FABK Transaction occurred on January 1, 2020. These results combine the historical results of TCB Holdings and FABK into the Company's consolidated statement of income and, while certain adjustments were made for the estimated impact of certain fair value adjustments, they are not indicative of what would have occurred had the acquisitions taken place on the indicated date nor are they intended to represent or be indicative of future results of operations. In particular, no adjustments have been made to eliminate the amount of TCB Holdings' or FABK's provision for credit losses for the first three and nine months of 2020 that may not have been necessary had the acquired loans been recorded at fair value as of the beginning of 2020. Additionally, these financials were not adjusted for non-recurring expenses, such as merger-related charges incurred by either the Company, TCB Holdings or FABK. The Company expects to achieve operating cost savings and other business synergies as a result of the acquisitions which are also not reflected in the pro forma amounts. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Revenue (1) $ 39,868 $ 36,541 $ 114,102 $ 97,623 Net interest income $ 28,999 $ 30,539 $ 87,586 $ 82,686 Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 13,768 (1) Net interest income plus noninterest income

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS ASC 855, Subsequent Events, establishes general standards of accounting for and disclosure of events that occur after the balance sheet date but before financial statements are issued. Reliant Bancorp evaluated all events or transactions that occurred after September 30, 2021 through the date of the issued financial statements. On October 19, 2021, the board of directors of Reliant Bancorp declared a quarterly cash dividend of $0.12 per share payable on November 12, 2021 to shareholders of record as of the close of business on October 29, 2021.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of OperationsReliant Bancorp, Inc. is a Tennessee corporation and the holding company for and the sole shareholder of Reliant Bank (the "Bank"), collectively, "the Company". Reliant Bancorp is registered as a bank holding company under the Bank Holding Company Act of 1956, as amended ("Bank Holding Company Act"). Reliant Bancorp has elected under the Bank Holding Company Act to be a financial holding company. Reliant Bank is a commercial bank chartered under Tennessee law and a member of the Federal Reserve System (the "Federal Reserve"). The Bank provides a full range of traditional banking products and services to business and consumer clients throughout Middle Tennessee.
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with instructions to Quarterly Report on Form 10-Q and, therefore, do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, and cash flows in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP"). All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods covered by the report have been included. The accompanying unaudited consolidated financial statements should be read in conjunction with the Company's consolidated financial statements and related notes appearing in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. Amounts in the footnotes are shown in thousands, except for numbers of shares, per share amounts and as otherwise noted. The consolidated financial statements as of and for the periods presented include Reliant Bancorp, Inc., its wholly-owned direct and indirect subsidiaries and Reliant Mortgage Ventures, LLC ("RMV"), of which the Bank controls 51% of the governance rights. As described in Note 11 to these unaudited consolidated financial statements, Reliant Bancorp, Inc. and Tennessee Community Bank Holdings, Inc. (“TCB Holdings”) merged effective on January 1, 2020, and Reliant Bancorp, Inc. and First Advantage Bancorp (“FABK”) merged effective April 1, 2020. Proposed Merger with United Community Banks, Inc. On July 14, 2021, United Community Banks, Inc. (NASDAQGS: UCBI) (“United”) and Reliant Bancorp announced the execution of a definitive merger agreement pursuant to which United will acquire Reliant Bancorp in an all-stock transaction with an aggregate value of approximately $517 million, or $30.58 per share of Reliant Bancorp common stock, based on United’s closing stock price of $31.07 on July 13, 2021. This agreement is subject to both regulatory and Reliant Bancorp shareholder approval. The transaction is expected to close in the first quarter of 2022.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions based on available information. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to determination of the allowance for loan losses, the valuation of other real estate, the valuation of debt and equity securities, the valuation of deferred tax assets and fair values of financial instruments. The consolidated financial statements as of September 30, 2021, and for the three and nine months ended September 30, 2021 and 2020, included herein have not been audited. The accounting and reporting policies of the Company conform to U.S. GAAP and Article 8 of Regulation S-X. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission, although the Company believes that the disclosures made are adequate to make the information not misleading.
Recently Adopted Accounting Pronouncements and Newly Issued not yet Effective Accounting Standards	Recently Adopted Accounting Pronouncements Information about certain issued accounting standards updates is presented below. Also refer to Note 1 - Summary of Significant Accounting Policies, in the Company's Annual Report on Form 10-K for the year ended December 31, 2020 for additional information related to previously issued accounting standards updates. ASU 2019-12, “Income Taxes (Topic 740) - Simplifying the Accounting for Income Taxes.” The guidance issued in this update simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition for deferred tax liabilities for outside basis differences. ASU 2019-12 also simplifies aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. ASU 2019-12 was effective for us on January 1, 2021, and did not have a significant impact on our consolidated financial statements. ASU 2020-04, "Reference Rate Reform (Topic 848 ) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting." In March 2020, the Financial Accounting Standards Board (“FASB”) issued Topic 848 amendments to provide optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. It provides optional expedients and exceptions for applying generally accepted accounting principles to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this update are effective for all entities as of March 12, 2020 through December 31, 2022. The Company has evaluated the effect of the pronouncement on the consolidated financial statements, noting no significant impact. Newly Issued not yet Effective Accounting Standards ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts and requires enhanced disclosures related to the significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an organization’s portfolio. In addition, ASU 2016-13 amends the accounting for credit losses on available for sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 is expected to be effective for the Company on January 1, 2023. We are currently evaluating the potential impact of ASU 2016-13 on the Company's financial statements by developing an implementation plan to include assessment of processes, portfolio segmentation, model development, system requirements and the identification of data and resource needs, among other things. The adoption of ASU 2016-13 could result in an increase in the allowance for loan losses as a result of changing from an “incurred loss” model, which encompasses allowances for current known and inherent losses within the portfolio, to an “expected loss” model, which encompasses allowances for losses expected to be incurred over the life of the portfolio. Furthermore, ASU 2016-13 will necessitate that we establish an allowance for expected credit losses for certain debt securities and other financial assets. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Financial Instruments - Credit Losses (ASC 326), Derivatives and Hedging (ASC 815), and Financial Instruments (ASC 825) . The amendments in this ASU improve the codification by eliminating inconsistencies and providing clarifications. The amended guidance in this ASU related to credit losses is expected to be effective for the Company in conjunction with the adoption of the standard on January 1, 2023. The Company is currently evaluating the impact of these ASUs on the Company’s consolidated financial statements. While we are currently unable to reasonably estimate the impact of adopting these ASUs, we expect that the impact of adoption will be significantly influenced by the composition, characteristics and quality of the Company's loan and securities portfolios as well as the prevailing economic conditions and forecasts as of the adoption date.

Securities (Tables)

Securities (Tables)	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-Sale Securities	The amortized cost and fair value of available for sale securities and the related gross unrealized gains and losses recognized in accumulated other comprehensive income at September 30, 2021 and December 31, 2020 were as follows: September 30, 2021 Amortized Gross Gross Estimated U. S. Treasury and other U. S. government agencies $ 218 $ — $ — $ 218 State and municipal 161,733 10,039 (801) 170,971 Corporate bonds 27,000 1,160 (8) 28,152 Mortgage-backed securities - Residential 52,736 295 (208) 52,823 Asset-backed securities 2,270 1 (19) 2,252 Total $ 243,957 $ 11,495 $ (1,036) $ 254,416 December 31, 2020 Amortized Gross Gross Estimated U. S. Treasury and other U. S. government agencies $ 47 $ 1 $ — $ 48 State and municipal 184,102 16,963 (77) 200,988 Corporate bonds 23,750 397 (34) 24,113 Mortgage-backed securities - Residential 28,084 360 (2) 28,442 Asset-backed securities 3,083 1 (22) 3,062 Total $ 239,066 $ 17,722 $ (135) $ 256,653 Results from sales of securities were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Proceeds $ 23,104 $ 233 $ 58,855 $ 103,901 Gross gains 2,419 371 5,514 810 Gross losses — (371) — (483)
Schedule of Investments Classified by Contractual Maturity Date	The fair values of available for sale debt securities at September 30, 2021 by contractual maturity are provided below. Actual maturities may differ from contractual maturities for mortgage- and asset-backed securities since the underlying asset may be called or prepaid with or without penalty. Securities not due at a single maturity date are shown separately. Amortized Estimated Due within one year $ 218 $ 218 Due in one to five years 2,085 2,120 Due in five to ten years 31,473 33,239 Due after ten years 155,175 163,764 Mortgage-backed securities 52,736 52,823 Asset-backed securities 2,270 2,252 Total $ 243,957 $ 254,416
Schedule of Unrealized Loss on Investments	The following table shows available for sale securities with unrealized losses and their estimated fair value aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of September 30, 2021 and December 31, 2020, respectively: Less than 12 months 12 months or more Total Estimated Unrealized Estimated Unrealized Estimated Unrealized September 30, 2021 State and municipal $ 37,064 $ 801 $ — $ — $ 37,064 $ 801 Corporate bonds 1,742 8 — — 1,742 8 Mortgage-backed securities - Residential 33,283 207 74 1 33,357 208 Asset-backed securities — — 2,045 19 2,045 19 Total temporarily impaired $ 72,089 $ 1,016 $ 2,119 $ 20 $ 74,208 $ 1,036 December 31, 2020 State and municipal $ 9,475 $ 77 $ — $ — $ 9,475 $ 77 Corporate bonds 5,716 34 — — 5,716 34 Mortgage-backed securities - Residential 5,024 1 92 1 5,116 2 Asset-backed securities 729 2 2,013 20 2,742 22 Total temporarily impaired $ 20,944 $ 114 $ 2,105 $ 21 $ 23,049 $ 135

Loans and Allowance for Loan _2

Loans and Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2021
Receivables [Abstract]
Schedule of Loans and Allowance for Loan Losses	Loans at September 30, 2021 and December 31, 2020 were comprised as follows: September 30, 2021 December 31, 2020 Commercial, Industrial and Agricultural $ 450,710 $ 459,739 Real Estate 1-4 Family Residential 310,855 323,473 1-4 Family HELOC 100,895 100,525 Multi-family and Commercial 873,265 834,000 Construction, Land Development and Farmland 417,258 365,058 Consumer 234,734 213,863 Other 5,298 8,669 Gross loans 2,393,015 2,305,327 Less: Deferred loan fees 3,182 4,544 Less: Allowance for loan losses 20,897 20,636 Loans, net $ 2,368,936 $ 2,280,147
Schedule of Credit Quality Indicators By Class of Loan	The following table provides the risk category of loans by applicable class of loans including purchase credit impaired (“PCI”) loans as of September 30, 2021 and December 31, 2020: Pass Special Substandard Total September 30, 2021 Loans excluding PCI Commercial, Industrial and Agricultural $ 448,003 $ 1,077 $ 1,573 $ 450,653 1-4 Family Residential Real Estate 308,977 1 1,234 310,212 1-4 Family HELOC 100,529 — 352 100,881 Multi-family and Commercial Real Estate 867,351 257 5,144 872,752 Construction, Land Development and Farmland 415,235 — 1,304 416,539 Consumer 232,185 1 1,747 233,933 Other 5,298 — — 5,298 Total loans excluding PCI $ 2,377,578 $ 1,336 $ 11,354 $ 2,390,268 Total PCI loans $ 1,031 $ — $ 1,716 $ 2,747 Total loans $ 2,378,609 $ 1,336 $ 13,070 $ 2,393,015 Pass Special Substandard Total December 31, 2020 Loans excluding PCI Commercial, Industrial and Agricultural $ 456,170 $ 1,519 $ 1,863 $ 459,552 1-4 Family Residential Real Estate 320,555 5 2,165 322,725 1-4 Family HELOC 100,391 — 120 100,511 Multi-family and Commercial Real Estate 829,353 653 3,337 833,343 Construction, Land Development and Farmland 358,606 — 5,676 364,282 Consumer 211,305 7 1,346 212,658 Other 7,150 1,519 — 8,669 Total loans excluding PCI $ 2,283,530 $ 3,703 $ 14,507 $ 2,301,740 Total PCI loans $ 998 $ — $ 2,589 $ 3,587 Total loans $ 2,284,528 $ 3,703 $ 17,096 $ 2,305,327
Schedule of Activity in the Allowance for Loan Losses By Portfolio Segment	Activity in the Allowance for Loan Loss (“ALL”) by portfolio segment was as follows for the three and nine months ended September 30, 2021 and 2020: Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total Beginning balance at June 30, 2021 $ 6,614 $ 1,923 $ 610 $ 8,498 $ 2,011 $ 1,222 $ 16 $ 20,894 Charge-offs (3) (42) — — — (150) — (195) Recoveries 14 58 2 42 1 81 — 198 Provision 362 (642) (2) 66 78 143 (5) — Ending balance at September 30, 2021 $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Beginning balance at June 30, 2020 $ 4,675 $ 1,454 $ 975 $ 8,407 $ 2,126 $ 584 $ 16 $ 18,237 Charge-offs — (8) — — — (60) — (68) Recoveries 88 22 12 9 4 30 — 165 Provision 249 821 498 (169) (175) 272 4 1,500 Ending balance at September 30, 2020 $ 5,012 $ 2,289 $ 1,485 $ 8,247 $ 1,955 $ 826 $ 20 $ 19,834 Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total Beginning balance at December 31, 2020 $ 5,441 $ 2,445 $ 1,416 $ 8,535 $ 1,841 $ 928 $ 30 $ 20,636 Charge-offs (35) (63) — — — (604) — (702) Recoveries 315 154 7 257 92 138 — 963 Provision 1,266 (1,239) (813) (186) 157 834 (19) — Ending balance at September 30, 2021 $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Beginning balance at December 31, 2019 $ 2,529 $ 1,280 $ 624 $ 5,285 $ 2,649 $ 177 $ 34 $ 12,578 Charge-offs (507) (68) (98) — (114) (355) — (1,142) Recoveries 126 769 15 20 8 60 — 998 Provision 2,864 308 944 2,942 (588) 944 (14) 7,400 Ending balance at September 30, 2020 $ 5,012 $ 2,289 $ 1,485 $ 8,247 $ 1,955 $ 826 $ 20 $ 19,834
Schedule of Allowance for Credit Losses and Recorded Investments in Loans By Portfolio and By Impairment Method	The ALL and the recorded investment in loans by portfolio segment and based on impairment method as of was as follows: Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total September 30, 2021 Allowance for loan losses Individually evaluated for impairment $ 847 $ — $ — $ — $ 67 $ 4 $ — $ 918 Acquired with credit impairment — — — — — — — — Collectively evaluated for impairment 6,140 1,297 610 8,606 2,023 1,292 11 19,979 Total $ 6,987 $ 1,297 $ 610 $ 8,606 $ 2,090 $ 1,296 $ 11 $ 20,897 Loans Individually evaluated for impairment $ 1,433 $ 1,371 $ 352 $ 5,390 $ 1,750 $ 1,747 $ — $ 12,043 Acquired with credit impairment 57 643 14 513 719 801 — 2,747 Collectively evaluated for impairment 449,220 308,841 100,529 867,362 414,789 232,186 5,298 2,378,225 Total $ 450,710 $ 310,855 $ 100,895 $ 873,265 $ 417,258 $ 234,734 $ 5,298 $ 2,393,015 Commercial Industrial and Agricultural 1-4 Family Residential Real Estate 1-4 Family HELOC Multi-family and Commercial Construction Land Development and Farmland Consumer Other Total December 31, 2020 Allowance for loan losses Individually evaluated for impairment $ 717 $ 18 $ — $ — $ — $ 13 $ — $ 748 Acquired with credit impairment — — — — — — — — Collectively evaluated for impairment 4,724 2,427 1,416 8,535 1,841 915 30 19,888 Total $ 5,441 $ 2,445 $ 1,416 $ 8,535 $ 1,841 $ 928 $ 30 $ 20,636 Loans Individually evaluated for impairment $ 1,027 $ 1,829 $ 110 $ 2,504 $ 5,676 $ 1,177 $ — $ 12,323 Acquired with credit impairment 187 748 14 657 776 1,205 — 3,587 Collectively evaluated for impairment 458,525 320,896 100,401 830,839 358,606 211,481 8,669 2,289,417 Total $ 459,739 $ 323,473 $ 100,525 $ 834,000 $ 365,058 $ 213,863 $ 8,669 $ 2,305,327
Schedule of Past Due Status By Class of Loan	The following tables provide the period-end amounts of loans that are past due thirty to eighty-nine days, past due ninety or more days and still accruing interest, loans not accruing interest, purchased credit impaired loans, and loans current on payments accruing interest by category at September 30, 2021 and December 31, 2020: Current and Accruing 30-89 Days Past Due 90+ Days Nonaccrual Loans Total Loans September 30, 2021 Loans excluding PCI Commercial, Industrial and Agricultural $ 450,349 $ 19 $ — $ 285 $ 450,653 1-4 Family Residential Real Estate 308,897 503 — 812 310,212 1-4 Family HELOC 100,777 — — 104 100,881 Multi-family and Commercial Real Estate 871,921 — — 831 872,752 Construction, Land Development and Farmland 415,350 144 — 1,045 416,539 Consumer 231,504 1,347 5 1,077 233,933 Other 5,298 — — — 5,298 Total loans excluding PCI $ 2,384,096 $ 2,013 $ 5 $ 4,154 $ 2,390,268 Total PCI loans $ 1,580 $ 24 $ — $ 1,143 $ 2,747 Total loans $ 2,385,676 $ 2,037 $ 5 $ 5,297 $ 2,393,015 Current and Accruing 30-89 Days Past Due 90+ Days Nonaccrual Loans Total Loans December 31, 2020 Loans excluding PCI Commercial, Industrial and Agricultural $ 458,974 $ 126 $ — $ 452 $ 459,552 1-4 Family Residential Real Estate 319,180 2,071 — 1,474 322,725 1-4 Family HELOC 100,501 10 — — 100,511 Multi-family and Commercial Real Estate 832,697 150 — 496 833,343 Construction, Land Development and Farmland 363,376 — — 906 364,282 Consumer 210,552 1,413 1 692 212,658 Other 8,669 — — — 8,669 Total loans excluding PCI $ 2,293,949 $ 3,770 $ 1 $ 4,020 $ 2,301,740 Total PCI loans $ 1,584 $ 37 $ — $ 1,966 $ 3,587 Total loans $ 2,295,533 $ 3,807 $ 1 $ 5,986 $ 2,305,327
Schedule of Outstanding Balance and Carrying Amount of the Purchased Credit Impaired Loans	The Company has purchased loans, for which there was, at acquisition, evidence of deterioration of credit quality since origination and it was probable, at acquisition that all contractually required payments would not be collected. The carrying amount of those loans is as follows: September 30, 2021 December 31, 2020 Commercial, Industrial and Agricultural $ 782 $ 919 1-4 Family Residential Real Estate 868 1,004 1-4 Family HELOC 19 19 Multi-family and Commercial Real Estate 1,175 1,325 Construction, Land Development and Farmland 935 992 Consumer 1,426 1,924 Total outstanding balance 5,205 6,183 Less remaining purchase discount 2,458 2,596 Allowance for loan losses — — Carrying amount, net of allowance for loan losses and remaining purchase discounts $ 2,747 $ 3,587
Schedule of Activity Related to Accretable Portion of the Purchase Discount on Loans Acquired With Deteriorated Credit Quality	Accretable yield, or income expected to be collected on PCI loans, is as follows: 2021 2020 Balance at January 1, $ 580 $ 98 New loans purchased — 870 Accretion income (52) (137) Balance at September 30, $ 528 $ 831
Schedule of Acquisition that All Contractually Required Payment	PCI loans purchased during the year ended December 31, 2020, for which it was probable at acquisition that all contractually required payments would not be collected are as follows: Tennessee Community Bank Holdings, Inc. acquisition on January 1, 2020 First Advantage Bancorp acquisition on April 1, 2020 Contractually required payments receivable of loans purchased during the year: $ 2,799 $ 7,540 Nonaccretable difference (980) (2,133) Cash flows expected to be collected at acquisition $ 1,819 $ 5,407 Accretable yield (131) (739) Fair value of acquired loans at acquisition $ 1,688 $ 4,668
Schedule of Individually Impaired Loans by Class of Loans	Individually impaired loans by class of loans were as follows at September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Unpaid Recorded Investment Related Unpaid Recorded Investment Related With no related allowance recorded Commercial, Industrial and Agricultural $ 1,691 $ 642 $ — $ 1,400 $ 367 $ — 1-4 Family Residential Real Estate 2,419 2,015 — 3,034 2,473 — 1-4 Family HELOC 378 366 — 130 124 — Multi-family and Commercial Real Estate 7,141 5,903 — 4,549 3,161 — Construction, Land Development and Farmland 2,617 2,210 — 6,809 6,452 — Consumer 3,848 2,512 — 3,590 2,348 — Subtotal $ 18,094 $ 13,648 $ — $ 19,512 $ 14,925 $ — With an allowance recorded Commercial, Industrial and Agricultural $ 859 $ 847 $ 847 $ 859 $ 847 $ 717 1-4 Family Residential Real Estate — — — 104 104 18 1-4 Family HELOC — — — — — — Multi-family and Commercial Real Estate — — — — — — Construction, Land Development and Farmland 259 259 67 — — — Consumer 39 36 4 34 34 13 Subtotal 1,157 1,142 918 997 985 748 Total $ 19,251 $ 14,790 $ 918 $ 20,509 $ 15,910 $ 748
Schedule of Average Balances of Impaired Loans	The average recorded investment in impaired loans for the three and nine months ended September 30, 2021, and 2020 was as follows: Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average recorded investment Interest income recognized Average recorded investment Interest income recognized With no allowance Commercial, Industrial and Agricultural $ 444 $ 6 $ 594 $ 42 $ 355 $ 26 $ 354 $ 56 1-4 Family Residential Real Estate 2,044 31 3,002 54 2,296 109 2,631 154 1-4 Family HELOC 332 3 331 — 272 11 367 — Multi-family and Commercial Real Estate 5,655 86 4,375 63 4,741 271 4,138 278 Construction, Land Development and Farmland 4,222 42 2,949 28 5,424 114 2,471 115 Consumer 2,473 83 2,118 68 2,411 275 1,076 205 Subtotal $ 15,170 $ 251 $ 13,369 $ 255 $ 15,499 $ 806 $ 11,037 $ 808 Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average recorded investment Interest income recognized Average recorded investment Interest income recognized With an allowance recorded Commercial, Industrial and Agricultural $ 847 $ 6 $ 947 $ 6 $ 847 $ 18 $ 976 $ 32 1-4 Family Residential Real Estate — — — — 26 — — — 1-4 Family HELOC — — — — — — — — Multi-family and Commercial Real Estate 50 — — — 38 — — — Construction, Land Development and Farmland 86 3 — — 65 4 43 — Consumer 46 1 — — 43 2 1 — Subtotal $ 1,029 $ 10 $ 947 $ 6 $ 1,019 $ 24 $ 1,020 $ 32 Total $ 16,199 $ 261 $ 14,316 $ 261 $ 16,518 $ 830 $ 12,057 $ 840
Schedule of Troubles Debt Loans by Class of Loans	Modifications made during the nine months ended September 30, 2020 are displayed below. Number of Contracts Pre-Modification Outstanding Recorded Investments Post-Modification Outstanding Recorded Investments Commercial, Industrial and Agricultural 1 $ 150 $ 150 1-4 Family Residential 1 721 721 Multi-family and Commercial Real Estate 1 394 394 Total 3 $ 1,265 $ 1,265
Schedule of Class of Finance Receivable on Active Deferral Status	September 30, 2021 Active Deferrals % of Loans Multi-family and Commercial $ 67,372 2.82 %
Schedule Of Coronavirus, Aid, Relief, And Economic Securities (CARES) Act, Loan Program, Income Recognized	Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Interest $ 19 $ 210 $ 216 $ 358 Fees 176 455 1,808 739 Total PPP Income $ 195 $ 665 $ 2,024 $ 1,097

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss)	Summary information related to the interest rate swaps designated as cash flow hedges as of September 30, 2021, is as follows: Notional amounts $ 10,000 Weighted average pay rates 5.19 % Weighted average receive rates 2.38 % Weighted average maturity 1.71 years Unrealized losses $ 468 The following table presents the net gains (losses) recorded in accumulated other comprehensive income net of tax, relating to the cash flow derivative instruments for the three and nine months ended September 30, 2021 and 2020, respectively: Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss) Three months ended September 30, Nine months ended September 30, 2021 2020 2021 2020 Interest rate swaps - subordinate debentures $ 47 $ 51 $ 164 $ (230) Interest rate swaps - interest-bearing liabilities 1,562 324 5,146 (4,532) $ 1,609 $ 375 $ 5,310 $ (4,762)
Cash Flow Hedges Included in the Consolidated Balance Sheets	The following table reflects the cash flow hedges included in the Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 December 31, 2020 Notional Amount Fair Value Notional Amount Fair Value Included in other liabilities: Interest rate swaps related to: Subordinated debentures $ 10,000 $ (468) $ 10,000 $ (690) Short-term interest-bearing liabilities — — 150,000 (6,967) Total included in other liabilities $ 10,000 $ (468) $ 160,000 $ (7,657)
Schedule of Derivative Instruments for Fair Value hedges	Fair Value Hedges Summary information related to the fair value hedges as of September 30, 2021, is as follows: Notional amounts $ 17,090 Weighted average pay rates 3.68 % Weighted average receive rates 1.10 % Weighted average maturity 7.44 years Unrealized losses $ 848
Schedule of Fair Value Hedging Included in the Consolidated Balance Sheets	The following table reflects the fair value hedges included in the Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020, respectively: September 30, 2021 December 31, 2020 Notional Amount Fair Value Notional Amount Fair Value Included in other liabilities: Interest rate swaps related to investments 17,090 (848) 18,525 (1,495) Total included in other liabilities $ 17,090 $ (848) $ 18,525 $ (1,495) The following table reflects the fair value hedges and the underlying hedged items included in the Consolidated Statements of Income for the three and nine months ended September 30, 2021 and 2020, respectively: Three months ended September 30, Nine months ended September 30, Item Location 2021 2020 2021 2020 Interest rate swaps - securities Interest on investment securities, nontaxable $ (118) $ (118) $ (356) $ (243) Hedged item - securities Interest on investment securities, nontaxable $ 118 $ 118 $ 356 $ 243

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Stock-Based Compensation Expense and Employee Benefit Services	The Company has recognized stock-based compensation expense, within salaries and employee benefits for employees, and within other non-interest expense for directors, in the consolidated statement of income as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Stock-based compensation expense before income taxes $ 458 $ 349 $ 1,265 $ 1,183 Less: deferred tax benefit (120) (91) (331) (309) Reduction of net income $ 338 $ 258 $ 934 $ 874
Share-based Compensation, Stock Options, Activity	A summary of stock option activity for the nine months ended September 30, 2021 is as follows: Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at December 31, 2020 116,621 $ 18.97 5.87 years $ 304 Granted — $ — Exercised (1,702) $ 14.36 20 Forfeited or expired (5,600) $ 13.42 Outstanding at September 30, 2021 109,319 $ 19.33 5.32 years $ 1,340 Exercisable at September 30, 2021 86,519 $ 17.88 4.81 years $ 1,186
Activity Related to Non-Vested Restricted Stock	The following table shows the activity related to non-vested restricted stock and restricted stock unit awards for the nine months ended September 30, 2021: Restricted Stock Units Restricted Stock Underlying Shares Weighted Average Grant-Date Shares Weighted Average Grant-Date Outstanding at January 1, 2021 132,650 $ 16.93 40,910 $ 26.82 Granted 70,655 26.07 — — Vested (14,400) 14.81 (35,410) 27.54 Forfeited (9,500) 17.59 — — Outstanding at September 30, 2021 179,405 $ 20.67 5,500 $ 22.17

Regulatory Capital Requiremen_2

Regulatory Capital Requirements (Tables)	9 Months Ended
	Sep. 30, 2021
Banking and Thrift, Other Disclosures [Abstract]
Actual and Required Capital Amounts and Ratios	Capital amounts and ratios for Reliant Bancorp and the Bank are presented below as of September 30, 2021 and December 31, 2020. Actual Minimum Required To Be Well Amount Ratio Amount Ratio Amount Ratio September 30, 2021 Reliant Bancorp Tier I leverage $ 297,367 10.04 % $ 118,473 4.00 % $ 148,091 5.00 % Common equity tier I 285,537 10.52 % 189,996 7.00 % 176,425 6.50 % Tier I risk-based capital 297,367 10.95 % 230,833 8.50 % 217,254 8.00 % Total risk-based capital 377,977 13.92 % 285,112 10.50 % 271,535 10.00 % Bank Tier I leverage $ 347,450 11.76 % $ 118,185 4.00 % $ 147,732 5.00 % Common equity tier I 347,450 14.10 % 172,493 7.00 % 160,172 6.50 % Tier I risk-based capital 347,450 14.10 % 209,456 8.50 % 197,135 8.00 % Total risk-based capital 369,072 14.98 % 258,695 10.50 % 246,377 10.00 % Actual Minimum Required To Be Well December 31, 2020 Reliant Bancorp Tier I leverage $ 262,282 8.91 % $ 117,747 4.00 % $ 147,184 5.00 % Common equity tier I 250,513 10.22 % 171,584 7.00 % 159,328 6.50 % Tier I risk-based capital 262,282 10.70 % 208,355 8.50 % 196,099 8.00 % Total risk-based capital 342,246 13.96 % 257,420 10.50 % 245,162 10.00 % Bank Tier I leverage $ 313,633 10.64 % $ 117,907 4.00 % $ 147,384 5.00 % Common equity tier I 313,633 12.83 % 171,117 7.00 % 158,894 6.50 % Tier I risk-based capital 313,633 12.83 % 207,785 8.50 % 195,562 8.00 % Total risk-based capital 334,919 13.71 % 256,503 10.50 % 244,288 10.00 %

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Summary of the Components Comprising Basic and Diluted Earnings Per Share	The following is a summary of the components comprising basic and diluted earnings per common share of stock ("EPS"): Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Basic EPS Computation Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 19,186 Weighted average common shares outstanding 16,665,155 16,587,274 16,632,587 15,053,087 Basic earnings per common share $ 0.80 $ 0.70 $ 2.31 $ 1.27 Diluted EPS Computation Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 19,186 Weighted average common shares outstanding 16,665,155 16,587,274 16,632,587 15,053,087 Dilutive effect of stock options, restricted stock shares and units, and employee stock purchase plan 140,002 62,399 144,385 67,616 Adjusted weighted average common shares outstanding 16,805,157 16,649,673 16,776,972 15,120,703 Diluted earnings per common share $ 0.79 $ 0.69 $ 2.29 $ 1.27

Fair Values of Assets and Lia_2

Fair Values of Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis	The following table sets forth the Company’s major categories of assets and liabilities measured at fair value on a recurring basis, by level within the fair value hierarchy, as of September 30, 2021 and December 31, 2020: Fair Value Quoted Significant Significant September 30, 2021 Assets U. S. Treasury and other U. S. government agencies $ 218 $ — $ 218 $ — State and municipal 170,971 — 170,971 — Corporate bonds 28,152 — 28,152 — Mortgage-backed securities 52,823 — 52,823 — Asset-backed securities 2,252 — 2,252 — Liabilities Derivative liabilities $ 1,316 $ — $ 1,316 $ — December 31, 2020 Assets U. S. Treasury and other U. S. government agencies $ 48 $ — $ 48 $ — State and municipal 200,988 — 200,988 — Corporate bonds 24,113 — 24,113 — Mortgage-backed securities 28,442 — 28,442 — Asset-backed securities 3,062 — 3,062 — Liabilities Derivative liabilities $ 9,152 $ — $ 9,152 $ — The following table sets forth the Company’s major categories of assets and liabilities measured at fair value on a nonrecurring basis, by level within the fair value hierarchy, as of September 30, 2021 and December 31, 2020: Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs September 30, 2021 Assets Impaired loans $ 13,872 $ — $ — $ 13,872 Other real estate 3,088 — — 3,088 Other repossessions 865 — — 865 December 31, 2020 Assets Impaired loans $ 15,162 $ — $ — $ 15,162 Other real estate 1,246 — — 1,246 Other repossessions 1,424 — — 1,424
Schedule of Level 3 Input Information for Assets Measured at Fair Value on a Nonrecurring Basis	The following table presents additional quantitative information about assets measured at fair value on a nonrecurring basis and for which we have utilized Level 3 inputs to determine fair value at September 30, 2021 and December 31, 2020: Valuation Significant Range Impaired loans Appraisal Estimated costs to sell 10% Other real estate Appraisal Estimated costs to sell 10% Other repossessions Third-party guidelines Estimated costs to sell 10% (1) The fair value is generally determined through independent appraisals of the underlying collateral, which may include Level 3 inputs that are not identifiable, or by using the discounted cash flow method if the loan is not collateral dependent. Estimated cash flows change and appraised values of the assets or collateral underlying the loans will be sensitive to changes.
Schedule of Carrying Amounts And Estimated Fair Values of Financial instruments Not Reported at Fair Value	Carrying amounts and estimated fair values of financial instruments not reported at fair value at September 30, 2021 and December 31, 2020 were as follows: September 30, 2021 Carrying Estimated Quoted Prices in Significant Significant Financial assets Cash and due from banks $ 13,270 $ 13,270 $ 13,270 $ — $ — Interest-bearing deposits in financial institutions 66,155 66,155 66,155 — — Federal funds sold 1,002 1,002 — 1,002 — Loans, net 2,368,936 2,393,109 — — 2,393,109 Mortgage loans held for sale 62,543 62,521 — 62,521 — Accrued interest receivable 14,374 14,374 — 14,374 — Restricted equity securities 15,770 15,770 — 15,770 — Financial liabilities Deposits $ 2,547,705 $ 2,548,511 $ — $ — $ 2,548,511 Accrued interest payable 2,302 2,302 — 2,302 — Subordinate debentures 70,821 72,373 — — 72,373 Federal Home Loan Bank advances — — — — — December 31, 2020 Carrying Estimated Quoted Prices in Significant Significant Financial assets Cash and due from banks $ 13,717 $ 13,717 $ 13,717 $ — $ — Interest-bearing deposits in financial institutions 79,756 79,756 79,756 — — Federal funds sold 1,572 1,572 — 1,572 — Loans, net 2,280,147 2,293,723 — — 2,293,723 Mortgage loans held for sale 147,524 149,342 — 149,342 — Accrued interest receivable 14,889 14,889 — 14,889 — Restricted equity securities 16,551 16,551 — 16,551 — Financial liabilities Deposits $ 2,579,235 $ 2,583,525 $ — $ — $ 2,583,525 Accrued interest payable 2,571 2,571 — 2,571 — Subordinate debentures 70,446 71,750 — — 71,750 Federal Home Loan Bank advances 10,000 10,000 — — 10,000

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Summarized Results of Operations by Business Segment	The following presents summarized results of operations for the Company’s business segments for the periods indicated: Three Months Ended Commercial Banking Residential Elimination Consolidated Net interest income $ 28,164 $ 835 $ — $ 28,999 Provision for loan losses — — — — Noninterest income 6,651 4,177 41 10,869 Noninterest expense (excluding merger expense) 16,551 4,377 — 20,928 Merger expense 1,453 — — 1,453 Income tax expense 3,522 29 — 3,551 Net income 13,289 606 41 13,936 Noncontrolling interest in net income of subsidiary — (606) (41) (647) Net income attributable to common shareholders $ 13,289 $ — $ — $ 13,289 Three Months Ended Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 29,731 $ 808 $ — $ 30,539 Provision for loan losses 1,500 — — 1,500 Noninterest income 2,219 3,797 (14) 6,002 Noninterest expense (excluding merger expense) 16,067 4,190 — 20,257 Merger expense 77 — — 77 Income tax (benefit) expense 2,773 27 — 2,800 Net (loss) income 11,533 388 (14) 11,907 Noncontrolling interest in net income of subsidiary — (388) 14 (374) Net income attributable to common shareholders $ 11,533 $ — $ — $ 11,533 Nine months ended September 30, 2021 Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 84,737 $ 2,849 $ — $ 87,586 Provision for loan losses — — — — Noninterest income 14,395 12,461 (340) 26,516 Noninterest expense (excluding merger expense) 49,581 13,495 — 63,076 Merger expense 1,453 — — 1,453 Income tax expense (benefit) 9,615 118 — 9,733 Net income (loss) 38,483 1,697 (340) 39,840 Noncontrolling interest in net income of subsidiary — (1,697) 340 (1,357) Net income attributable to common shareholders $ 38,483 $ — $ — $ 38,483 Nine months ended September 30, 2020 Commercial Banking Residential Mortgage Banking Elimination Entries Consolidated Net interest income $ 75,933 $ 1,677 $ — $ 77,610 Provision for loan losses 7,400 — — 7,400 Noninterest income 6,102 7,601 3 13,706 Noninterest expense (excluding merger expense) 44,961 10,340 — 55,301 Merger expense 6,895 — — 6,895 Income tax expense (benefit) 3,593 (69) — 3,524 Net income (loss) 19,186 (993) 3 18,196 Noncontrolling interest in net loss of subsidiary — 993 (3) 990 Net income attributable to common shareholders $ 19,186 $ — $ — $ 19,186

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Calculation and Allocation of Purchase Price	The following table details the financial impact of the TCB Holdings Transaction, including the calculation of the purchase price, the allocation of the purchase price to the fair values of net assets assumed and goodwill recognized: Calculation of Purchase Price Shares of Tennessee Community Bank Holdings, Inc. common stock outstanding as of January 1, 2020 1,055,041 Exchange ratio for Reliant Bancorp, Inc. common stock 0.769 Reliant Bancorp, Inc. common stock shares issued 811,210 Reliant Bancorp, Inc. share price at January 1, 2020 $ 22.24 Estimated value of Reliant Bancorp, Inc. shares issued 18,041 Cash settlement for Tennessee Community Bank Holdings, Inc. common stock ($17.13 per share) 18,073 Cash settlement for Tennessee Community Bank Holdings, Inc.'s 26,450 outstanding stock options ($34.25 settlement price less weighted average exercise price of $18.00) 430 Cash settlement for Reliant Bancorp, Inc. fractional shares ($22.36 per pro rata fractional share) 3 Estimated fair value of Tennessee Community Bank Holdings, Inc. $ 36,547 Allocation of Purchase Price Total consideration above $ 36,547 Fair value of assets acquired and liabilities assumed Cash and cash equivalents 11,026 Investment securities available for sale 56,336 Loans, net of unearned income 171,445 Accrued interest receivable 948 Premises and equipment 5,221 Cash surrender value of life insurance contracts 5,629 Restricted equity securities 909 Core deposit intangible 3,617 Other assets 833 Deposits (210,538) Deferred tax liability (157) Borrowings (58) FHLB advances (13,102) Other liabilities (4,337) Total fair value of net assets acquired 27,772 Goodwill $ 8,775 The following table details the financial impact of the FABK Transaction, including the calculation of the purchase price, the allocation of the purchase price to the fair values of net assets assumed and goodwill recognized: Calculation of Purchase Price Shares of First Advantage Bancorp common stock outstanding as of April 1, 2020 3,935,165 Conversion of restricted stock units to shares of common stock of First Advantage Bancorp as of April 1, 2020 2,000 Total First Advantage Bancorp common stock outstanding as of April 1, 2020 3,937,165 Exchange ratio for Reliant Bancorp, Inc. common stock 1.17 Reliant Bancorp, Inc. common stock shares issued 4,606,483 Remove fractional shares (64) Reliant Bancorp, Inc. common stock shares issued 4,606,419 Reliant Bancorp, Inc. share price at April 1, 2020 $ 11.27 Estimated value of Reliant Bancorp, Inc. shares issued 51,914 Cash settlement for Reliant Bancorp, Inc. fractional shares ($11.74 per pro rata fractional share) 1 Cash settlement for First Advantage Bancorp common stock ($3.00 per share) 11,805 Cash settlement for First Advantage Bancorp restricted stock units ($3.00 per share) 6 Cash settlement for First Advantage Bancorp's 34,800 outstanding stock options ($30.00 settlement price less weighted average exercise price of $19.44) 368 Estimated fair value of First Advantage Bancorp $ 64,094 Allocation of Purchase Price Total consideration above $ 64,094 Fair value of assets acquired and liabilities assumed Cash and cash equivalents 11,159 Investment securities available for sale 35,970 Loans, net of unearned income 622,423 Mortgage loans held for sale, net 5,878 Premises and equipment 7,757 Deferred tax asset 4,937 Cash surrender value of life insurance contracts 14,776 Other real estate and repossessed assets 1,259 Core deposit intangible 2,280 Operating lease right-of-use assets 5,846 Other assets 11,624 Deposits (608,690) Borrowings (35,962) Operating lease liabilities (6,536) Other liabilities (10,606) Total fair value of net assets acquired 62,115 Goodwill $ 1,979
Schedule of Operating Cost Savings and Other Business Synergies	The Company expects to achieve operating cost savings and other business synergies as a result of the acquisitions which are also not reflected in the pro forma amounts. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Revenue (1) $ 39,868 $ 36,541 $ 114,102 $ 97,623 Net interest income $ 28,999 $ 30,539 $ 87,586 $ 82,686 Net income attributable to common shareholders $ 13,289 $ 11,533 $ 38,483 $ 13,768 (1) Net interest income plus noninterest income

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 14, 2021	Sep. 30, 2021	Jul. 13, 2021
COMMON STOCK
Noncontrolling Interest [Line Items]
Share price (in dollars per share)			$ 31.07
United Community Banks, Inc
Noncontrolling Interest [Line Items]
Total consideration transferred	$ 517
United Community Banks, Inc | COMMON STOCK
Noncontrolling Interest [Line Items]
Share price (in dollars per share)	$ 30.58
Reliant Mortgage Ventures, LLC
Noncontrolling Interest [Line Items]
Governance rights control by the bank		51.00%

Securities - Available-for-sale

Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 243,957	$ 239,066
Gross Unrealized Gains	11,495	17,722
Gross Unrealized Losses	(1,036)	(135)
Estimated Fair Value	254,416	256,653
U. S. Treasury and other U. S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	218	47
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Estimated Fair Value	218	48
State and municipal
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	161,733	184,102
Gross Unrealized Gains	10,039	16,963
Gross Unrealized Losses	(801)	(77)
Estimated Fair Value	170,971	200,988
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	27,000	23,750
Gross Unrealized Gains	1,160	397
Gross Unrealized Losses	(8)	(34)
Estimated Fair Value	28,152	24,113
Mortgage-backed securities - Residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	52,736	28,084
Gross Unrealized Gains	295	360
Gross Unrealized Losses	(208)	(2)
Estimated Fair Value	52,823	28,442
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,270	3,083
Gross Unrealized Gains	1	1
Gross Unrealized Losses	(19)	(22)
Estimated Fair Value	$ 2,252	$ 3,062

Securities - Narrative (Details

Securities - Narrative (Details) $ in Thousands	Sep. 30, 2021USD ($)security	Dec. 31, 2020USD ($)security
Investments, Debt and Equity Securities [Abstract]
Securities pledged, carrying amount | $	$ 35,376	$ 30,491
Number of securities in unrealized loss position | security	48	22

Securities - Results from Sales

Securities - Results from Sales of Securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Proceeds	$ 23,104	$ 233	$ 58,855	$ 103,901
Gross gains	2,419	371	5,514	810
Gross losses	$ 0	$ (371)	$ 0	$ (483)

Securities - Available-for-sa_2

Securities - Available-for-sale Securities Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost
Due within one year	$ 218
Due in one to five years	2,085
Due in five to ten years	31,473
Due after ten years	155,175
Amortized Cost	243,957	$ 239,066
Estimated Fair Value
Due within one year	218
Due in one to five years	2,120
Due in five to ten years	33,239
Due after ten years	163,764
Estimated Fair Value	254,416	256,653
Mortgage-backed securities
Amortized Cost
Securities	52,736
Amortized Cost	52,736	28,084
Estimated Fair Value
Securities	52,823
Estimated Fair Value	52,823	28,442
Asset-backed securities
Amortized Cost
Securities	2,270
Amortized Cost	2,270	3,083
Estimated Fair Value
Securities	2,252
Estimated Fair Value	$ 2,252	$ 3,062

Securities - Schedule of Tempor

Securities - Schedule of Temporary Impairment Losses, Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Estimated Fair Value
Less than 12 months	$ 72,089	$ 20,944
12 months or more	2,119	2,105
Total	74,208	23,049
Unrealized Loss
Less than 12 months	1,016	114
12 months or more	20	21
Total	1,036	135
State and municipal
Estimated Fair Value
Less than 12 months	37,064	9,475
12 months or more	0	0
Total	37,064	9,475
Unrealized Loss
Less than 12 months	801	77
12 months or more	0	0
Total	801	77
Corporate bonds
Estimated Fair Value
Less than 12 months	1,742	5,716
12 months or more	0	0
Total	1,742	5,716
Unrealized Loss
Less than 12 months	8	34
12 months or more	0	0
Total	8	34
Mortgage-backed securities - Residential
Estimated Fair Value
Less than 12 months	33,283	5,024
12 months or more	74	92
Total	33,357	5,116
Unrealized Loss
Less than 12 months	207	1
12 months or more	1	1
Total	208	2
Asset-backed securities
Estimated Fair Value
Less than 12 months	0	729
12 months or more	2,045	2,013
Total	2,045	2,742
Unrealized Loss
Less than 12 months	0	2
12 months or more	19	20
Total	$ 19	$ 22

Loans and Allowance for Loan _3

Loans and Allowance for Loan Losses - Schedule of Loans and Financial Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 2,393,015		$ 2,305,327
Less: Deferred loan fees	3,182		4,544
Less: Allowance for loan losses	20,897	$ 20,894	20,636	$ 19,834	$ 18,237	$ 12,578
Loans, net	2,368,936		2,280,147
Commercial, Industrial and Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	450,710		459,739
Less: Allowance for loan losses	6,987	6,614	5,441	5,012	4,675	2,529
Real Estate | 1-4 Family Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	310,855		323,473
Less: Allowance for loan losses	1,297	1,923	2,445	2,289	1,454	1,280
Real Estate | 1-4 Family HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	100,895		100,525
Less: Allowance for loan losses	610	610	1,416	1,485	975	624
Real Estate | Multi-family and Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	873,265		834,000
Less: Allowance for loan losses	8,606	8,498	8,535	8,247	8,407	5,285
Real Estate | Construction, Land Development and Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	417,258		365,058
Less: Allowance for loan losses	2,090	2,011	1,841	1,955	2,126	2,649
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	234,734		213,863
Less: Allowance for loan losses	1,296	1,222	928	826	584	177
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	5,298		8,669
Less: Allowance for loan losses	$ 11	$ 16	$ 30	$ 20	$ 16	$ 34

Loans and Allowance for Loan _4

Loans and Allowance for Loan Losses - Narrative (Details)	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)loan	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)loan	Dec. 31, 2020USD ($)	Apr. 01, 2020USD ($)	Jan. 01, 2020USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Discount on loans purchased			$ 11,993,000	$ 16,634,000
FHLB advances, collateral pledged loans	$ 857,394,000		857,394,000	646,498,000
Nonaccrual Loans	5,297,000		5,297,000	5,986,000
Loan modifications, recorded investment	2,903,000		2,903,000	4,236,000
Modified loan amount	$ 0	$ 0	0
SBA authorizations for PPP loans, amount			83,366,000
SBA forgiven for PPP loans, amount			$ 83,075,000
Commercial, Industrial and Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan	7		7
SBA authorizations for PPP loans, amount			$ 292,000
Tennessee Community Bank Holdings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value						$ 170,000,000
Fair value of acquired loans at acquisition						$ 1,688,000
First Advantage Bancorp
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value					$ 625,800,000
Fair value of acquired loans at acquisition					$ 4,668,000
Performing Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual Loans	$ 1,973,000		1,973,000	2,438,000
Nonperforming Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual Loans	$ 977,000		$ 977,000	$ 630,000

Loans and Allowance for Loan _5

Loans and Allowance for Loan Losses - Summary of Credit Quality Indicators by Class of Loan (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 2,393,015	$ 2,305,327
Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,390,268	2,301,740
PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,747	3,587
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,378,609	2,284,528
Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,377,578	2,283,530
Pass | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,031	998
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,336	3,703
Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,336	3,703
Special Mention | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	13,070	17,096
Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	11,354	14,507
Substandard | PCI Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,716	2,589
Commercial, Industrial and Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	450,710	459,739
Commercial, Industrial and Agricultural | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	450,653	459,552
Commercial, Industrial and Agricultural | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	448,003	456,170
Commercial, Industrial and Agricultural | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,077	1,519
Commercial, Industrial and Agricultural | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,573	1,863
Real Estate | 1-4 Family Residential Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	310,855	323,473
Real Estate | 1-4 Family Residential Real Estate | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	310,212	322,725
Real Estate | 1-4 Family Residential Real Estate | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	308,977	320,555
Real Estate | 1-4 Family Residential Real Estate | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1	5
Real Estate | 1-4 Family Residential Real Estate | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,234	2,165
Real Estate | 1-4 Family HELOC
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	100,895	100,525
Real Estate | 1-4 Family HELOC | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	100,881	100,511
Real Estate | 1-4 Family HELOC | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	100,529	100,391
Real Estate | 1-4 Family HELOC | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Real Estate | 1-4 Family HELOC | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	352	120
Real Estate | Multi-family and Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	873,265	834,000
Real Estate | Multi-family and Commercial Real Estate | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	872,752	833,343
Real Estate | Multi-family and Commercial Real Estate | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	867,351	829,353
Real Estate | Multi-family and Commercial Real Estate | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	257	653
Real Estate | Multi-family and Commercial Real Estate | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,144	3,337
Real Estate | Construction, Land Development and Farmland
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	417,258	365,058
Real Estate | Construction, Land Development and Farmland | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	416,539	364,282
Real Estate | Construction, Land Development and Farmland | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	415,235	358,606
Real Estate | Construction, Land Development and Farmland | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	0
Real Estate | Construction, Land Development and Farmland | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,304	5,676
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	234,734	213,863
Consumer | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	233,933	212,658
Consumer | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	232,185	211,305
Consumer | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1	7
Consumer | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,747	1,346
Other
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,298	8,669
Other | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,298	8,669
Other | Pass | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,298	7,150
Other | Special Mention | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	0	1,519
Other | Substandard | Loans excluding PCI
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 0	$ 0

Loans and Allowance for Loan _6

Loans and Allowance for Loan Losses - Schedule of Allowances for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 20,894	$ 18,237	$ 20,636	$ 12,578
Charge-offs	(195)	(68)	(702)	(1,142)
Recoveries	198	165	963	998
Provision	0	1,500	0	7,400
Ending balance	20,897	19,834	20,897	19,834
Commercial Industrial and Agricultural
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,614	4,675	5,441	2,529
Charge-offs	(3)	0	(35)	(507)
Recoveries	14	88	315	126
Provision	362	249	1,266	2,864
Ending balance	6,987	5,012	6,987	5,012
Real Estate | 1-4 Family Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,923	1,454	2,445	1,280
Charge-offs	(42)	(8)	(63)	(68)
Recoveries	58	22	154	769
Provision	(642)	821	(1,239)	308
Ending balance	1,297	2,289	1,297	2,289
Real Estate | 1-4 Family HELOC
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	610	975	1,416	624
Charge-offs	0	0	0	(98)
Recoveries	2	12	7	15
Provision	(2)	498	(813)	944
Ending balance	610	1,485	610	1,485
Real Estate | Multi-family and Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,498	8,407	8,535	5,285
Charge-offs	0	0	0	0
Recoveries	42	9	257	20
Provision	66	(169)	(186)	2,942
Ending balance	8,606	8,247	8,606	8,247
Real Estate | Construction Land Development and Farmland
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,011	2,126	1,841	2,649
Charge-offs	0	0	0	(114)
Recoveries	1	4	92	8
Provision	78	(175)	157	(588)
Ending balance	2,090	1,955	2,090	1,955
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,222	584	928	177
Charge-offs	(150)	(60)	(604)	(355)
Recoveries	81	30	138	60
Provision	143	272	834	944
Ending balance	1,296	826	1,296	826
Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	16	16	30	34
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(5)	4	(19)	(14)
Ending balance	$ 11	$ 20	$ 11	$ 20

Loans and Allowance for Loan _7

Loans and Allowance for Loan Losses - Allowance for Loan Losses and Recorded Investment by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Allowance for loan losses
Individually evaluated for impairment	$ 918		$ 748
Acquired with credit impairment	0		0
Collectively evaluated for impairment	19,979		19,888
Total allowance for loan losses	20,897	$ 20,894	20,636	$ 19,834	$ 18,237	$ 12,578
Loans
Individually evaluated for impairment	12,043		12,323
Acquired with credit impairment	2,747		3,587
Collectively evaluated for impairment	2,378,225		2,289,417
Total loans	2,393,015		2,305,327
Commercial, Industrial and Agricultural
Allowance for loan losses
Individually evaluated for impairment	847		717
Acquired with credit impairment	0		0
Collectively evaluated for impairment	6,140		4,724
Total allowance for loan losses	6,987	6,614	5,441	5,012	4,675	2,529
Loans
Individually evaluated for impairment	1,433		1,027
Acquired with credit impairment	57		187
Collectively evaluated for impairment	449,220		458,525
Total loans	450,710		459,739
Real Estate | 1-4 Family Residential
Allowance for loan losses
Individually evaluated for impairment	0		18
Acquired with credit impairment	0		0
Collectively evaluated for impairment	1,297		2,427
Total allowance for loan losses	1,297	1,923	2,445	2,289	1,454	1,280
Loans
Individually evaluated for impairment	1,371		1,829
Acquired with credit impairment	643		748
Collectively evaluated for impairment	308,841		320,896
Total loans	310,855		323,473
Real Estate | 1-4 Family HELOC
Allowance for loan losses
Individually evaluated for impairment	0		0
Acquired with credit impairment	0		0
Collectively evaluated for impairment	610		1,416
Total allowance for loan losses	610	610	1,416	1,485	975	624
Loans
Individually evaluated for impairment	352		110
Acquired with credit impairment	14		14
Collectively evaluated for impairment	100,529		100,401
Total loans	100,895		100,525
Real Estate | Multi-family and Commercial
Allowance for loan losses
Individually evaluated for impairment	0		0
Acquired with credit impairment	0		0
Collectively evaluated for impairment	8,606		8,535
Total allowance for loan losses	8,606	8,498	8,535	8,247	8,407	5,285
Loans
Individually evaluated for impairment	5,390		2,504
Acquired with credit impairment	513		657
Collectively evaluated for impairment	867,362		830,839
Total loans	873,265		834,000
Real Estate | Construction, Land Development and Farmland
Allowance for loan losses
Individually evaluated for impairment	67		0
Acquired with credit impairment	0		0
Collectively evaluated for impairment	2,023		1,841
Total allowance for loan losses	2,090	2,011	1,841	1,955	2,126	2,649
Loans
Individually evaluated for impairment	1,750		5,676
Acquired with credit impairment	719		776
Collectively evaluated for impairment	414,789		358,606
Total loans	417,258		365,058
Consumer
Allowance for loan losses
Individually evaluated for impairment	4		13
Acquired with credit impairment	0		0
Collectively evaluated for impairment	1,292		915
Total allowance for loan losses	1,296	1,222	928	826	584	177
Loans
Individually evaluated for impairment	1,747		1,177
Acquired with credit impairment	801		1,205
Collectively evaluated for impairment	232,186		211,481
Total loans	234,734		213,863
Other
Allowance for loan losses
Individually evaluated for impairment	0		0
Acquired with credit impairment	0		0
Collectively evaluated for impairment	11		30
Total allowance for loan losses	11	$ 16	30	$ 20	$ 16	$ 34
Loans
Individually evaluated for impairment	0		0
Acquired with credit impairment	0		0
Collectively evaluated for impairment	5,298		8,669
Total loans	$ 5,298		$ 8,669

Loans and Allowance for Loan _8

Loans and Allowance for Loan Losses - Summary of Past Due (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Loans	$ 2,393,015	$ 2,305,327
90+ Days Past Due and Accruing Interest	5	1
Nonaccrual Loans	5,297	5,986
Total loans	2,393,015	2,305,327
Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	2,390,268	2,301,740
90+ Days Past Due and Accruing Interest	5	1
Nonaccrual Loans	4,154	4,020
Total loans	2,390,268	2,301,740
PCI Loans
Financing Receivable, Past Due [Line Items]
Loans	2,747	3,587
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	1,143	1,966
Total loans	2,747	3,587
Current and Accruing
Financing Receivable, Past Due [Line Items]
Loans	2,385,676	2,295,533
Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	2,384,096	2,293,949
Current and Accruing | PCI Loans
Financing Receivable, Past Due [Line Items]
Loans	1,580	1,584
30-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,037	3,807
30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	2,013	3,770
30-89 Days Past Due | PCI Loans
Financing Receivable, Past Due [Line Items]
Loans	24	37
Commercial, Industrial and Agricultural
Financing Receivable, Past Due [Line Items]
Loans	450,710	459,739
Commercial, Industrial and Agricultural | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	450,653	459,552
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	285	452
Total loans	450,653	459,552
Commercial, Industrial and Agricultural | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	450,349	458,974
Commercial, Industrial and Agricultural | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	19	126
Real Estate | 1-4 Family Residential
Financing Receivable, Past Due [Line Items]
Loans	310,855	323,473
Real Estate | 1-4 Family Residential | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	310,212	322,725
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	812	1,474
Total loans	310,212	322,725
Real Estate | 1-4 Family Residential | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	308,897	319,180
Real Estate | 1-4 Family Residential | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	503	2,071
Real Estate | 1-4 Family HELOC
Financing Receivable, Past Due [Line Items]
Loans	100,895	100,525
Real Estate | 1-4 Family HELOC | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	100,881	100,511
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	104	0
Total loans	100,881	100,511
Real Estate | 1-4 Family HELOC | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	100,777	100,501
Real Estate | 1-4 Family HELOC | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	0	10
Real Estate | Multi-family and Commercial
Financing Receivable, Past Due [Line Items]
Loans	873,265	834,000
Real Estate | Multi-family and Commercial | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	872,752	833,343
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	831	496
Total loans	872,752	833,343
Real Estate | Multi-family and Commercial | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	871,921	832,697
Real Estate | Multi-family and Commercial | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	0	150
Real Estate | Construction, Land Development and Farmland
Financing Receivable, Past Due [Line Items]
Loans	417,258	365,058
Real Estate | Construction, Land Development and Farmland | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	416,539	364,282
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	1,045	906
Total loans	416,539	364,282
Real Estate | Construction, Land Development and Farmland | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	415,350	363,376
Real Estate | Construction, Land Development and Farmland | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	144	0
Consumer
Financing Receivable, Past Due [Line Items]
Loans	234,734	213,863
Consumer | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	233,933	212,658
90+ Days Past Due and Accruing Interest	5	1
Nonaccrual Loans	1,077	692
Total loans	233,933	212,658
Consumer | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	231,504	210,552
Consumer | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	1,347	1,413
Other
Financing Receivable, Past Due [Line Items]
Loans	5,298	8,669
Other | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	5,298	8,669
90+ Days Past Due and Accruing Interest	0	0
Nonaccrual Loans	0	0
Total loans	5,298	8,669
Other | Current and Accruing | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	5,298	8,669
Other | 30-89 Days Past Due | Loans excluding PCI
Financing Receivable, Past Due [Line Items]
Loans	$ 0	$ 0

Loans and Allowance for Loan _9

Loans and Allowance for Loan Losses - Summary of Carrying Amount of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	$ 5,205	$ 6,183
Less remaining purchase discount	2,458	2,596
Allowance for loan losses	0	0
Carrying amount, net of allowance for loan losses and remaining purchase discounts	2,747	3,587
Commercial, Industrial and Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	782	919
Real Estate | 1-4 Family Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	868	1,004
Real Estate | 1-4 Family HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	19	19
Real Estate | Multi-family and Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	1,175	1,325
Real Estate | Construction, Land Development and Farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	935	992
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total outstanding balance	$ 1,426	$ 1,924

Loans and Allowance for Loan_10

Loans and Allowance for Loan Losses - Activity Related to Accretable Portion of Loans Acquired (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at January 1,	$ 580	$ 98
New loans purchased	0	870
Accretion income	(52)	(137)
Balance at September 30,	$ 528	$ 831

Loans and Allowance for Loan_11

Loans and Allowance for Loan Loss - PCI Loans Purchased (Details) - USD ($) $ in Thousands	Apr. 01, 2020	Jan. 01, 2020
Tennessee Community Bank Holdings
Loans and Leases Receivable Disclosure [Line Items]
Contractually required payments receivable of loans purchased during the year:		$ 2,799
Nonaccretable difference		(980)
Cash flows expected to be collected at acquisition		1,819
Accretable yield		(131)
Fair value of acquired loans at acquisition		$ 1,688
First Advantage Bancorp
Loans and Leases Receivable Disclosure [Line Items]
Contractually required payments receivable of loans purchased during the year:	$ 7,540
Nonaccretable difference	(2,133)
Cash flows expected to be collected at acquisition	5,407
Accretable yield	(739)
Fair value of acquired loans at acquisition	$ 4,668

Loans and Allowance for Loan_12

Loans and Allowance for Loan Losses - Summary of Individually Impaired Loans by Class of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	$ 18,094	$ 19,512
With an related allowance recorded unpaid principal balance	1,157	997
Unpaid Principal Balance	19,251	20,509
With no related allowance recorded investment	13,648	14,925
With an related allowance recorded, recorded investment	1,142	985
Recorded Investment	14,790	15,910
Related Allowance	918	748
Commercial, Industrial and Agricultural
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	1,691	1,400
With an related allowance recorded unpaid principal balance	859	859
With no related allowance recorded investment	642	367
With an related allowance recorded, recorded investment	847	847
Related Allowance	847	717
Real Estate | 1-4 Family Residential
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	2,419	3,034
With an related allowance recorded unpaid principal balance	0	104
With no related allowance recorded investment	2,015	2,473
With an related allowance recorded, recorded investment	0	104
Related Allowance	0	18
Real Estate | 1-4 Family HELOC
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	378	130
With an related allowance recorded unpaid principal balance	0	0
With no related allowance recorded investment	366	124
With an related allowance recorded, recorded investment	0	0
Related Allowance	0	0
Real Estate | Multi-family and Commercial
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	7,141	4,549
With an related allowance recorded unpaid principal balance	0	0
With no related allowance recorded investment	5,903	3,161
With an related allowance recorded, recorded investment	0	0
Related Allowance	0	0
Real Estate | Construction, Land Development and Farmland
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	2,617	6,809
With an related allowance recorded unpaid principal balance	259	0
With no related allowance recorded investment	2,210	6,452
With an related allowance recorded, recorded investment	259	0
Related Allowance	67	0
Consumer
Financing Receivable, Impaired [Line Items]
With no related allowance recorded unpaid principal balance	3,848	3,590
With an related allowance recorded unpaid principal balance	39	34
With no related allowance recorded investment	2,512	2,348
With an related allowance recorded, recorded investment	36	34
Related Allowance	$ 4	$ 13

Loans and Allowance for Loan_13

Loans and Allowance for Loan Losses - Summary of Average Balances of Impaired Loans and Interest Income Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	$ 15,170	$ 13,369	$ 15,499	$ 11,037
Impaired loans with an allowance, interest income recognized, subtotal	251	255	806	808
Impaired loans with no allowance, average recorded investment, subtotal	1,029	947	1,019	1,020
Impaired loans with no allowance, interest income recognized, subtotal	10	6	24	32
Average recorded investment, total	16,199	14,316	16,518	12,057
Interest income recognized, total	261	261	830	840
Commercial, Industrial and Agricultural
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	444	594	355	354
Impaired loans with an allowance, interest income recognized, subtotal	6	42	26	56
Impaired loans with no allowance, average recorded investment, subtotal	847	947	847	976
Impaired loans with no allowance, interest income recognized, subtotal	6	6	18	32
Real Estate | 1-4 Family Residential
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	2,044	3,002	2,296	2,631
Impaired loans with an allowance, interest income recognized, subtotal	31	54	109	154
Impaired loans with no allowance, average recorded investment, subtotal	0	0	26	0
Impaired loans with no allowance, interest income recognized, subtotal	0	0	0	0
Real Estate | 1-4 Family HELOC
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	332	331	272	367
Impaired loans with an allowance, interest income recognized, subtotal	3	0	11	0
Impaired loans with no allowance, average recorded investment, subtotal	0	0	0	0
Impaired loans with no allowance, interest income recognized, subtotal	0	0	0	0
Real Estate | Multi-family and Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	5,655	4,375	4,741	4,138
Impaired loans with an allowance, interest income recognized, subtotal	86	63	271	278
Impaired loans with no allowance, average recorded investment, subtotal	50	0	38	0
Impaired loans with no allowance, interest income recognized, subtotal	0	0	0	0
Real Estate | Construction, Land Development and Farmland
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	4,222	2,949	5,424	2,471
Impaired loans with an allowance, interest income recognized, subtotal	42	28	114	115
Impaired loans with no allowance, average recorded investment, subtotal	86	0	65	43
Impaired loans with no allowance, interest income recognized, subtotal	3	0	4	0
Consumer
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance, average recorded investment, subtotal	2,473	2,118	2,411	1,076
Impaired loans with an allowance, interest income recognized, subtotal	83	68	275	205
Impaired loans with no allowance, average recorded investment, subtotal	46	0	43	1
Impaired loans with no allowance, interest income recognized, subtotal	$ 1	$ 0	$ 2	$ 0

Loans and Allowance for Loan_14

Loans and Allowance for Loan Losses - Troubled Debt Restructurings (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)security
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | security	3
Pre-Modification Outstanding Recorded Investments	$ 1,265
Post-Modification Outstanding Recorded Investments	$ 1,265
Commercial, Industrial and Agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | security	1
Pre-Modification Outstanding Recorded Investments	$ 150
Post-Modification Outstanding Recorded Investments	$ 150
Real Estate | 1-4 Family Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | security	1
Pre-Modification Outstanding Recorded Investments	$ 721
Post-Modification Outstanding Recorded Investments	$ 721
Real Estate | Multi-family and Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | security	1
Pre-Modification Outstanding Recorded Investments	$ 394
Post-Modification Outstanding Recorded Investments	$ 394

Loans and Allowance for Loan_15

Loans and Allowance for Loan Losses - Active Deferrals (Details) - Real Estate - Multi-family and Commercial - CARES Act $ in Thousands	Sep. 30, 2021USD ($)
Financing Receivable, Nonaccrual [Line Items]
Active Deferrals	$ 67,372
% of Loans	2.82%

Loans and Allowance for Loan_16

Loans and Allowance for Loan Losses - CARES Act (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Receivables [Abstract]
Interest	$ 19	$ 210	$ 216	$ 358
Fees	176	455	1,808	739
Total PPP Income	$ 195	$ 665	$ 2,024	$ 1,097

Derivatives - Narrative (Detail

Derivatives - Narrative (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2021USD ($)
Derivative [Line Items]
Loss reclassified from accumulated other comprehensive income net	$ 2,290,000	$ 5,149,000
Interest Rate Swap
Derivative [Line Items]
Interest rate cash flow hedge, terminated value	100,000,000	150,000,000
Cash Flow Hedging | Interest Rate Swap
Derivative [Line Items]
Notional amounts	$ 10,000,000	$ 10,000,000

Derivatives - Interest Rate Swa

Derivatives - Interest Rate Swaps Designated as Cash Flow Hedges and Fair Value Hedges (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Interest Rate Swap
Derivative [Line Items]
Unrealized losses	$ 118,000	$ 118,000	$ 356,000	$ 243,000
Cash Flow Hedging | Interest Rate Swap
Derivative [Line Items]
Notional amounts	10,000,000		$ 10,000,000
Weighted average pay rates			5.19%
Weighted average receive rates			2.38%
Weighted average maturity			1 year 8 months 15 days
Unrealized losses			$ 468,000
Fair Value Hedging
Derivative [Line Items]
Notional amounts	$ 17,090,000		$ 17,090,000
Weighted average pay rates			3.68%
Weighted average receive rates			1.10%
Weighted average maturity			7 years 5 months 8 days
Unrealized losses			$ 848,000

Derivatives - Cash Flow Hedges

Derivatives - Cash Flow Hedges and Fair Value Hedges Included in the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Cash Flow Hedging | Other Liabilities
Derivative [Line Items]
Notional Amount	$ 10,000	$ 160,000
Fair Value	(468)	(7,657)
Cash Flow Hedging | Subordinated debentures | Interest Rate Swap
Derivative [Line Items]
Notional Amount	10,000	10,000
Fair Value	(468)	(690)
Cash Flow Hedging | Short-term interest-bearing liabilities | Interest Rate Swap
Derivative [Line Items]
Notional Amount	0	150,000
Fair Value	0	(6,967)
Fair Value Hedging | Other Liabilities
Derivative [Line Items]
Notional Amount	17,090	18,525
Fair Value	(848)	(1,495)
Fair Value Hedging | Other Liabilities | Interest Rate Swap
Derivative [Line Items]
Notional Amount	17,090	18,525
Fair Value	$ (848)	$ (1,495)

Derivatives - Net Gains (Losses

Derivatives - Net Gains (Losses) Relating to Cash Flow Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss)	$ 1,609	$ 375	$ 5,310	$ (4,762)
Interest rate swaps - subordinate debentures
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss)	47	51	164	(230)
Interest rate swaps - interest-bearing liabilities
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income (Loss)	$ 1,562	$ 324	$ 5,146	$ (4,532)

Derivatives - Fair Value Hedges

Derivatives - Fair Value Hedges Included in the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Change in unrealized gain (loss) on fair value hedging instruments	$ 118	$ 118	$ 356	$ 243
Interest Rate Swap
Derivative [Line Items]
Unrealized losses	$ (118)	$ (118)	$ (356)	$ (243)

Stock-based Compensation - Narr

Stock-based Compensation - Narrative (Details) - USD ($) $ in Thousands	Mar. 10, 2015	Sep. 30, 2021	Jun. 18, 2015	Dec. 31, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 144
Equity Incentive Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)			900,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period	10 years
Unrecognized compensation cost, weighted-average period for recognition		2 years 3 months 21 days
Employee Stock Option | The Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				625,000
Employee Stock Option | Commerce Union Bancshares, Inc. Amended and Restated Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	1,250,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, weighted-average period for recognition		2 years 3 days
Unrecognized compensation cost, restricted stock		$ 2,297
Fair value of share awards vested		$ 1,379
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, weighted-average period for recognition		7 months 13 days
Unrecognized compensation cost, restricted stock		$ 23

Stock-based Compensation - Expe

Stock-based Compensation - Expense and Employee Benefit Services (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Stock-based compensation expense before income taxes	$ 458	$ 349	$ 1,265	$ 1,183
Less: deferred tax benefit	(120)	(91)	(331)	(309)
Reduction of net income	$ 338	$ 258	$ 934	$ 874

Stock-based Compensation - Stoc

Stock-based Compensation - Stock Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares
Shares
Outstanding, beginning (in shares) | shares	116,621
Granted (in shares) | shares	0
Exercised (in shares) | shares	(1,702)
Forfeited or expired (in shares) | shares	(5,600)
Outstanding, ending (in shares) | shares	109,319	116,621
Exercisable (in shares) | shares	86,519
Weighted Average Exercise Price
Outstanding, beginning (in dollars per share) | $ / shares	$ 18.97
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	14.36
Forfeited or expired (in dollars per share) | $ / shares	13.42
Outstanding, ending (in dollars per share) | $ / shares	19.33	$ 18.97
Exercisable (in dollars per share) | $ / shares	$ 17.88
Weighted Average Remaining Contractual Term and Aggregate Intrinsic Value
Outstanding, weighted average remaining contractual term	5 years 3 months 25 days	5 years 10 months 13 days
Exercisable, weighted average remaining contractual term	4 years 9 months 21 days
Outstanding, aggregate intrinsic value | $	$ 1,340	$ 304
Exercised, aggregate intrinsic value | $	20
Exercisable, aggregate intrinsic value | $	$ 1,186

Stock-based Compensation - Nonv

Stock-based Compensation - Nonvested Restricted Stock Activity (Details)	9 Months Ended
	Sep. 30, 2021$ / sharesshares
Restricted Stock Units
Underlying Shares
Beginning balance (in shares) | shares	132,650
Granted (in shares) | shares	70,655
Vested (in shares) | shares	(14,400)
Forfeited (in shares) | shares	(9,500)
Ending balance (in shares) | shares	179,405
Weighted Average Grant-Date Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 16.93
Granted (in dollars per share) | $ / shares	26.07
Vested (in dollars per share) | $ / shares	14.81
Forfeited (in dollars per share) | $ / shares	17.59
Ending balance (in dollars per share) | $ / shares	$ 20.67
Restricted Stock
Underlying Shares
Beginning balance (in shares) | shares	40,910
Granted (in shares) | shares	0
Vested (in shares) | shares	(35,410)
Forfeited (in shares) | shares	0
Ending balance (in shares) | shares	5,500
Weighted Average Grant-Date Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 26.82
Granted (in dollars per share) | $ / shares	0
Vested (in dollars per share) | $ / shares	27.54
Forfeited (in dollars per share) | $ / shares	0
Ending balance (in dollars per share) | $ / shares	$ 22.17

Regulatory Capital Requiremen_3

Regulatory Capital Requirements (Details) $ in Thousands	Sep. 30, 2021USD ($)	Dec. 31, 2020USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier I leverage	$ 297,367	$ 262,282
Tier I leverage, ratio	0.1004	0.0891
Tier I leverage, minimum required capital including capital conservation buffer	$ 118,473	$ 117,747
Tier I leverage, minimum required capital including capital conservation buffer, ratio	4.00%	4.00%
Tier I leverage, to be well capitalized under prompt corrective action provisions	$ 148,091	$ 147,184
Tier I leverage, to be well capitalized under prompt corrective action provisions, ratio	0.0500	0.0500
Common equity tier 1	$ 285,537	$ 250,513
Common equity tier 1, ratio	0.1052	0.1022
Common equity tier 1, minimum required capital including capital conservation buffer	$ 189,996	$ 171,584
Common equity tier 1, minimum required capital including capital conservation buffer, ratio	7.00%	7.00%
Common equity tier 1, to be well capitalized under prompt corrective action provisions	$ 176,425	$ 159,328
Common equity tier 1, to be well capitalized under prompt corrective action provisions, ratio	6.50%	6.50%
Tier I risk-based capital	$ 297,367	$ 262,282
Tier I risk-based capital, ratio	0.1095	0.1070
Tier I risk-based capital, minimum required capital including capital conservation buffer	$ 230,833	$ 208,355
Tier I risk-based capital, minimum required capital including capital conservation buffer, ratio	8.50%	8.50%
Tier I risk-based capital, to be well capitalized under prompt corrective action provisions	$ 217,254	$ 196,099
Tier I risk-based capital, to be well capitalized under prompt corrective action provisions, ratio	0.0800	0.0800
Total risk-based capital	$ 377,977	$ 342,246
Total risk-based capital, ratio	0.1392	0.1396
Total risk-based capital, minimum required capital including capital conservation buffer	$ 285,112	$ 257,420
Total risk-based capital, minimum required capital including capital conservation buffer, ratio	10.50%	10.50%
Total risk-based capital, to be well capitalized under prompt corrective action provisions	$ 271,535	$ 245,162
Total risk-based capital, to be well capitalized under prompt corrective action provisions, ratio	0.1000	0.1000
Reliant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier I leverage	$ 347,450	$ 313,633
Tier I leverage, ratio	0.1176	0.1064
Tier I leverage, minimum required capital including capital conservation buffer	$ 118,185	$ 117,907
Tier I leverage, minimum required capital including capital conservation buffer, ratio	4.00%	4.00%
Tier I leverage, to be well capitalized under prompt corrective action provisions	$ 147,732	$ 147,384
Tier I leverage, to be well capitalized under prompt corrective action provisions, ratio	0.0500	0.0500
Common equity tier 1	$ 347,450	$ 313,633
Common equity tier 1, ratio	0.1410	0.1283
Common equity tier 1, minimum required capital including capital conservation buffer	$ 172,493	$ 171,117
Common equity tier 1, minimum required capital including capital conservation buffer, ratio	7.00%	7.00%
Common equity tier 1, to be well capitalized under prompt corrective action provisions	$ 160,172	$ 158,894
Common equity tier 1, to be well capitalized under prompt corrective action provisions, ratio	6.50%	6.50%
Tier I risk-based capital	$ 347,450	$ 313,633
Tier I risk-based capital, ratio	0.1410	0.1283
Tier I risk-based capital, minimum required capital including capital conservation buffer	$ 209,456	$ 207,785
Tier I risk-based capital, minimum required capital including capital conservation buffer, ratio	8.50%	8.50%
Tier I risk-based capital, to be well capitalized under prompt corrective action provisions	$ 197,135	$ 195,562
Tier I risk-based capital, to be well capitalized under prompt corrective action provisions, ratio	0.0800	0.0800
Total risk-based capital	$ 369,072	$ 334,919
Total risk-based capital, ratio	0.1498	0.1371
Total risk-based capital, minimum required capital including capital conservation buffer	$ 258,695	$ 256,503
Total risk-based capital, minimum required capital including capital conservation buffer, ratio	10.50%	10.50%
Total risk-based capital, to be well capitalized under prompt corrective action provisions	$ 246,377	$ 244,288
Total risk-based capital, to be well capitalized under prompt corrective action provisions, ratio	0.1000	0.1000

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Basic EPS Computation
Net income attributable to common shareholders	$ 13,289	$ 11,533	$ 38,483	$ 19,186
Weighted average common shares outstanding (in shares)	16,665,155	16,587,274	16,632,587	15,053,087
Basic earnings per common share (in dollars per share)	$ 0.80	$ 0.70	$ 2.31	$ 1.27
Diluted EPS Computation
Net income attributable to common shareholders	$ 13,289	$ 11,533	$ 38,483	$ 19,186
Weighted average common shares outstanding (in shares)	16,665,155	16,587,274	16,632,587	15,053,087
Dilutive effect of stock options, restricted stock shares and units, and employee stock purchase plan (in shares)	140,002	62,399	144,385	67,616
Adjusted weighted average common shares outstanding (in shares)	16,805,157	16,649,673	16,776,972	15,120,703
Diluted earnings per common share (in dollars per share)	$ 0.79	$ 0.69	$ 2.29	$ 1.27

Fair Values of Assets and Lia_3

Fair Values of Assets and Liabilities - Schedule of Fair Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 254,416	$ 256,653
Other real estate	3,088	1,246
U. S. Treasury and other U. S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	218	48
State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	170,971	200,988
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	28,152	24,113
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	52,823	28,442
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,252	3,062
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	1,316	9,152
Recurring | U. S. Treasury and other U. S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	218	48
Recurring | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	170,971	200,988
Recurring | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	28,152	24,113
Recurring | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	52,823	28,442
Recurring | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,252	3,062
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U. S. Treasury and other U. S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	1,316	9,152
Recurring | Significant Other Observable Inputs (Level 2) | U. S. Treasury and other U. S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	218	48
Recurring | Significant Other Observable Inputs (Level 2) | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	170,971	200,988
Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	28,152	24,113
Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	52,823	28,442
Recurring | Significant Other Observable Inputs (Level 2) | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,252	3,062
Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Recurring | Significant Unobservable Inputs (Level 3) | U. S. Treasury and other U. S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Recurring | Significant Unobservable Inputs (Level 3) | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	13,872	15,162
Other real estate	3,088	1,246
Other repossessions	865	1,424
Nonrecurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other real estate	0	0
Other repossessions	0	0
Nonrecurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other real estate	0	0
Other repossessions	0	0
Nonrecurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	13,872	15,162
Other real estate	3,088	1,246
Other repossessions	$ 865	$ 1,424

Fair Values of Assets and Lia_4

Fair Values of Assets and Liabilities - Summary of Quantitative Information of Assets Measured at Fair Value on Nonrecurring Basis by Utilized Level 3 Inputs (Details) - Estimated costs to sell - Range (Weighted Average) - Significant Unobservable Inputs (Level 3) - Nonrecurring	Sep. 30, 2021	Dec. 31, 2020
Appraisal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0.10	0.10
Other real estate	0.10	0.10
Third-party guidelines
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other repossessions	0.10	0.10

Fair Values of Assets and Lia_5

Fair Values of Assets and Liabilities - Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Carrying Amount
Financial assets
Cash and due from banks	$ 13,270	$ 13,717
Interest-bearing deposits in financial institutions	66,155	79,756
Federal funds sold	1,002	1,572
Loans, net	2,368,936	2,280,147
Mortgage loans held for sale	62,543	147,524
Accrued interest receivable	14,374	14,889
Restricted equity securities	15,770	16,551
Financial liabilities
Deposits	2,547,705	2,579,235
Accrued interest payable	2,302	2,571
Subordinate debentures	70,821	70,446
Federal Home Loan Bank advances	0	10,000
Estimated Fair Value
Financial assets
Cash and due from banks	13,270	13,717
Interest-bearing deposits in financial institutions	66,155	79,756
Federal funds sold	1,002	1,572
Loans, net	2,393,109	2,293,723
Mortgage loans held for sale	62,521	149,342
Accrued interest receivable	14,374	14,889
Restricted equity securities	15,770	16,551
Financial liabilities
Deposits	2,548,511	2,583,525
Accrued interest payable	2,302	2,571
Subordinate debentures	72,373	71,750
Federal Home Loan Bank advances	0	10,000
Estimated Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets
Cash and due from banks	13,270	13,717
Interest-bearing deposits in financial institutions	66,155	79,756
Federal funds sold	0	0
Loans, net	0	0
Mortgage loans held for sale	0	0
Accrued interest receivable	0	0
Restricted equity securities	0	0
Financial liabilities
Deposits	0	0
Accrued interest payable	0	0
Subordinate debentures	0	0
Federal Home Loan Bank advances	0	0
Estimated Fair Value | Significant Other Observable Inputs (Level 2)
Financial assets
Cash and due from banks	0	0
Interest-bearing deposits in financial institutions	0	0
Federal funds sold	1,002	1,572
Loans, net	0	0
Mortgage loans held for sale	62,521	149,342
Accrued interest receivable	14,374	14,889
Restricted equity securities	15,770	16,551
Financial liabilities
Deposits	0	0
Accrued interest payable	2,302	2,571
Subordinate debentures	0	0
Federal Home Loan Bank advances	0	0
Estimated Fair Value | Significant Unobservable Inputs (Level 3)
Financial assets
Cash and due from banks	0	0
Interest-bearing deposits in financial institutions	0	0
Federal funds sold	0	0
Loans, net	2,393,109	2,293,723
Mortgage loans held for sale	0	0
Accrued interest receivable	0	0
Restricted equity securities	0	0
Financial liabilities
Deposits	2,548,511	2,583,525
Accrued interest payable	0	0
Subordinate debentures	72,373	71,750
Federal Home Loan Bank advances	$ 0	$ 10,000

Segment Reporting - Narrative (

Segment Reporting - Narrative (Details)	9 Months Ended
	Sep. 30, 2021segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment Reporting - Summary of

Segment Reporting - Summary of Results of Operations for Company's Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Net interest income	$ 28,999			$ 30,539			$ 87,586	$ 77,610
Provision for loan losses	0			1,500			0	7,400
Noninterest income	10,869			6,002			26,516	13,706
Noninterest expense (excluding merger expense)	20,928			20,257			63,076	55,301
Merger expense	1,453			77			1,453	6,895
Income tax (benefit) expense	3,551			2,800			9,733	3,524
CONSOLIDATED NET INCOME	13,936	$ 13,185	$ 12,719	11,907	$ 7,480	$ (1,191)	39,840	18,196
Noncontrolling interest in net (income) loss of subsidiary	(647)			(374)			(1,357)	990
Net income attributable to common shareholders	13,289			11,533			38,483	19,186
Operating Segments | Commercial Banking
Segment Reporting Information [Line Items]
Net interest income	28,164			29,731			84,737	75,933
Provision for loan losses	0			1,500			0	7,400
Noninterest income	6,651			2,219			14,395	6,102
Noninterest expense (excluding merger expense)	16,551			16,067			49,581	44,961
Merger expense	1,453			77			1,453	6,895
Income tax (benefit) expense	3,522			2,773			9,615	3,593
CONSOLIDATED NET INCOME	13,289			11,533			38,483	19,186
Noncontrolling interest in net (income) loss of subsidiary	0			0			0	0
Net income attributable to common shareholders	13,289			11,533			38,483	19,186
Operating Segments | Residential Mortgage Banking
Segment Reporting Information [Line Items]
Net interest income	835			808			2,849	1,677
Provision for loan losses	0			0			0	0
Noninterest income	4,177			3,797			12,461	7,601
Noninterest expense (excluding merger expense)	4,377			4,190			13,495	10,340
Merger expense	0			0			0	0
Income tax (benefit) expense	29			27			118	(69)
CONSOLIDATED NET INCOME	606			388			1,697	(993)
Noncontrolling interest in net (income) loss of subsidiary	(606)			(388)			(1,697)	993
Net income attributable to common shareholders	0			0			0	0
Elimination Entries
Segment Reporting Information [Line Items]
Net interest income	0			0			0	0
Provision for loan losses	0			0			0	0
Noninterest income	41			(14)			(340)	3
Noninterest expense (excluding merger expense)	0			0			0	0
Merger expense	0			0			0	0
Income tax (benefit) expense	0			0			0	0
CONSOLIDATED NET INCOME	41			(14)			(340)	3
Noncontrolling interest in net (income) loss of subsidiary	(41)			14			340	(3)
Net income attributable to common shareholders	$ 0			$ 0			$ 0	$ 0

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income tax expense	$ 3,551	$ 2,800	$ 9,733	$ 3,524
Effective income tax rate	20.30%	19.00%	19.60%	16.20%

Business Combinations - Tenness

Business Combinations - Tennessee Community Bank Holdings TCB (Details) - USD ($)	Jan. 01, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)		$ 1		$ 1
Cash settlement for Tennessee Community Bank Holdings, Inc. common stock		$ 0	$ 8,500,000
COMMON STOCK
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)	$ 1
Business combination, shares issued per acquiree share (in shares)	0.769
Tennessee Community Bank Holdings
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)	$ 1
Reliant Bancorp, Inc. common stock shares issued (in shares)	811,210
Cash settlement for Tennessee Community Bank Holdings, Inc. common stock	$ 18,073,000
Cash in lieu of fractional shares based on volume weighted average closing consecutive	22.36
Exercise of stock option	34.25
Aggregate consideration paid to holders of unexercised options	$ 430,000	$ 430,000
Tennessee Community Bank Holdings | COMMON STOCK
Business Acquisition [Line Items]
Business acquisition, share price (in dollars per share)	$ 17.13

Business Combinations - Financi

Business Combinations - Financial Impact of Merger TCB (Details)	Jan. 01, 2020USD ($)$ / sharesshares	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Jul. 13, 2021$ / shares	Dec. 31, 2020USD ($)
Calculation of Purchase Price
Cash settlement for Tennessee Community Bank Holdings, Inc. common stock ($17.13 per share)		$ 0	$ 8,500,000
Allocation of Purchase Price
Goodwill		54,396,000			$ 54,396,000
COMMON STOCK
Calculation of Purchase Price
Reliant Bancorp, Inc. share price at January 1, 2020 (in dollars per share) | $ / shares				$ 31.07
Tennessee Community Bank Holdings
Calculation of Purchase Price
Shares of Tennessee Community Bank Holdings, Inc. common stock outstanding as of January 1, 2020 (in shares) | shares	1,055,041
Exchange ratio for Reliant Bancorp, Inc. common stock	0.769
Reliant Bancorp, Inc. common stock shares issued (in shares) | shares	811,210
Reliant Bancorp, Inc. share price at January 1, 2020 (in dollars per share) | $ / shares	$ 22.24
Estimated value of Reliant Bancorp, Inc. shares issued	$ 18,041,000
Cash settlement for Tennessee Community Bank Holdings, Inc. common stock ($17.13 per share)	18,073,000
Cash settlement for Tennessee Community Bank Holdings, Inc.'s 26,450 outstanding stock options ($34.25 settlement price less weighted average exercise price of $18.00)	430,000	$ 430,000
Cash settlement for Reliant Bancorp, Inc. fractional shares ($22.36 per pro rata fractional share)	3,000
Estimated fair value of Tennessee Community Bank Holdings, Inc.	$ 36,547,000
Number of stock options settled (in shares) | shares	26,450
Exercise of stock option	$ 34.25
Stock options weighted average exercise price (in dollars per share) | $ / shares	$ 18
Cash in lieu of fractional shares based on volume weighted average closing consecutive	$ 22.36
Allocation of Purchase Price
Total consideration above	36,547,000
Cash and cash equivalents	11,026,000
Investment securities available for sale	56,336,000
Loans, net of unearned income	171,445,000
Accrued interest receivable	948,000
Premises and equipment	5,221,000
Cash surrender value of life insurance contracts	5,629,000
Restricted equity securities	909,000
Core deposit intangible	3,617,000
Other assets	833,000
Deposits	(210,538,000)
Deferred tax liability	(157,000)
Borrowings	(58,000)
FHLB advances	(13,102,000)
Other liabilities	(4,337,000)
Total fair value of net assets acquired	27,772,000
Goodwill	$ 8,775,000
Tennessee Community Bank Holdings | COMMON STOCK
Calculation of Purchase Price
Business acquisition, share price (in dollars per share) | $ / shares	$ 17.13

Business Combinations - First A

Business Combinations - First Advantage Bancorp FABK (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 01, 2020	Sep. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)		$ 1	$ 1
Common stock, shares outstanding (in shares)		16,682,928	16,654,409
First Advantage Bancorp
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)	$ 0.01
Business combination, shares issued per acquiree share (in shares)	1.17
Business acquisition, share price (in dollars per share)	$ 3
Business combination, cash paid in lieu of fractional shares (in dollars per share)	11.74
Share price (in dollars per share)	$ 11.27
Common stock, shares outstanding (in shares)	3,935,165
Total consideration above	$ 64,094
Consideration transferred as price per share (in dollars per share)	$ 16.28

Business Combinations - Finan_2

Business Combinations - Financial Impact of Merger FABK (Details)	Apr. 01, 2020USD ($)$ / sharesshares	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Calculation of Purchase Price
Cash settlement for First Advantage Bancorp common stock ($3.00 per share)		$ 0	$ 8,500,000
Allocation of Purchase Price
Goodwill		$ 54,396,000		$ 54,396,000
First Advantage Bancorp
Calculation of Purchase Price
Shares of First Advantage Bancorp common stock outstanding as of April 1, 2020 (in shares) | shares	3,935,165
Conversion of restricted stock units to shares of common stock of First Advantage Bancorp as of April 1, 2020 (in shares) | shares	2,000
Total First Advantage Bancorp common stock outstanding as of April, 1, 2020 (in shares) | shares	3,937,165
Exchange ratio for Reliant Bancorp, Inc. common stock	1.17
Reliant Bancorp, Inc. common stock shares issued (in shares) | shares	4,606,483
Remove fractional shares (in shares) | shares	(64)
Reliant Bancorp, Inc. common stock shares issued (in shares) | shares	4,606,419
Reliant Bancorp, Inc. share price at April 1, 2020 (in dollars per share) | $ / shares	$ 11.27
Estimated value of Reliant Bancorp, Inc. shares issued	$ 51,914,000
Cash settlement for Reliant Bancorp, Inc. fractional shares ($11.74 per pro rata fractional share)	1,000
Cash settlement for First Advantage Bancorp common stock ($3.00 per share)	11,805,000
Cash settlement for First Advantage Bancorp restricted stock units ($3.00 per share)	6,000
Cash settlement for First Advantage Bancorp's 34,800 outstanding stock options ($30.00 settlement price less weighted average exercise price of $19.44)	368,000
Total consideration above	$ 64,094,000
Business combination, cash paid in lieu of fractional shares (in dollars per share) | $ / shares	$ 11.74
Business acquisition, share price (in dollars per share) | $ / shares	$ 3
Number of stock options settled (in shares) | shares	34,800
Exercise of stock option	$ 30
Stock options weighted average exercise price (in dollars per share) | $ / shares	$ 19.44
Allocation of Purchase Price
Total consideration above	$ 64,094,000
Cash and cash equivalents	11,159,000
Investment securities available for sale	35,970,000
Loans, net of unearned income	622,423,000
Mortgage loans held for sale, net	5,878,000
Premises and equipment	7,757,000
Deferred tax asset	4,937,000
Cash surrender value of life insurance contracts	14,776,000
Other real estate and repossessed assets	1,259,000
Core deposit intangible	2,280,000
Operating lease right-of-use assets	5,846,000
Other assets	11,624,000
Deposits	(608,690,000)
Borrowings	(35,962,000)
Operating lease liabilities	(6,536,000)
Other liabilities	(10,606,000)
Total fair value of net assets acquired	62,115,000
Goodwill	$ 1,979,000
First Advantage Bancorp | COMMON STOCK
Calculation of Purchase Price
Business acquisition, share price (in dollars per share) | $ / shares	$ 3
First Advantage Bancorp | Restricted Stock and Restricted Stock Units
Calculation of Purchase Price
Business acquisition, share price (in dollars per share) | $ / shares	$ 3

Business Combinations - Pro For

Business Combinations - Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Combination and Asset Acquisition [Abstract]
Revenue	$ 39,868	$ 36,541	$ 114,102	$ 97,623
Net interest income	28,999	30,539	87,586	82,686
Net income attributable to common shareholders	$ 13,289	$ 11,533	$ 38,483	$ 13,768

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	Oct. 19, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Subsequent Event [Line Items]
Cash dividends (in dollars per share)		$ 0.12	$ 0.12	$ 0.12	$ 0.10	$ 0.10	$ 0.10
Subsequent Event
Subsequent Event [Line Items]
Cash dividends (in dollars per share)	$ 0.12

Uncategorized Items - rbnc-2021

Label	Element	Value
Accounting Standards Update [Extensible Enumeration]	us-gaap_AccountingStandardsUpdateExtensibleList	Accounting Standards Update 2016-02 [Member]