United Community Banks (UCB) 10-K 25 Feb 21 2020 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-35095
Entity Registrant Name	UNITED COMMUNITY BANKS, INC.
Entity Central Index Key	0000857855
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Incorporation, State or Country Code	GA
Entity Tax Identification Number	58-1807304
Entity Address, Address Line One	125 Highway 515 East
Entity Address, City or Town	Blairsville
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30512
City Area Code	706
Local Phone Number	781-2265
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,567,580,828
Entity Common Stock, Shares Outstanding		86,736,280
Documents Incorporated by Reference	Portions of the registrant’s Proxy Statement for the 2021 Annual Meeting of Shareholders to be held on May 12, 2021 (the “2021 Proxy Statement”) are incorporated herein into Part III by reference.
Common stock, par value $1 per share
Entity Listings [Line Items]
Title of 12(b) Security	Common stock, par value $1 per share
Trading Symbol	UCBI
Security Exchange Name	NASDAQ
Depositary shares, each representing 1/1000th interest in a share of Series I Non-Cumulative Preferred Stock
Entity Listings [Line Items]
Title of 12(b) Security	Depositary shares, each representing 1/1000th interest in a share of Series I Non-Cumulative Preferred Stock
Trading Symbol	UCBIO
Security Exchange Name	NASDAQ

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Cash and due from banks	$ 148,896	$ 125,844
Interest-bearing deposits in banks	1,459,723	389,362
Cash and cash equivalents	1,608,619	515,206
Debt securities available-for-sale	3,224,721	2,274,581
Debt securities held-to-maturity (fair value $437,193 and $287,904, respectively)	420,361	283,533
Loans held for sale at fair value	105,433	58,484
Loans and leases held for investment	11,370,815	8,812,553
Less allowance for credit losses - loans and leases	(137,010)	(62,089)
Loans and leases, net	11,233,805	8,750,464
Premises and equipment, net	218,489	215,976
Bank owned life insurance	201,969	202,664
Accrued interest receivable	47,672	32,660
Net deferred tax asset	38,411	34,059
Derivative financial instruments	86,666	35,007
Goodwill and other intangible assets, net	381,823	342,247
Other assets	226,405	171,135
Total assets	17,794,374	12,916,016
Deposits:
Noninterest-bearing demand	5,390,291	3,477,979
Interest-bearing deposits	9,842,067	7,419,265
Total deposits	15,232,358	10,897,244
Long-term debt	326,956	212,664
Derivative financial instruments	29,003	15,516
Accrued expenses and other liabilities	198,527	154,900
Total liabilities	15,786,844	11,280,324
Commitments and contingencies
Shareholders' equity:
Preferred stock, $1 par value: 10,000,000 shares authorized; Series I, $25,000 per share liquidation preference; 4,000 and no shares issued and outstanding, respectively	96,422	0
Common stock, $1 par value; 150,000,000 shares authorized; 86,675,279 and 79,013,729 shares issued and outstanding, respectively	86,675	79,014
Common stock issuable; 600,834 and 664,640 shares, respectively	10,855	11,491
Capital surplus	1,638,999	1,496,641
Retained earnings	136,869	40,152
Accumulated other comprehensive income	37,710	8,394
Total shareholders’ equity	2,007,530	1,635,692
Total liabilities and shareholders’ equity	$ 17,794,374	$ 12,916,016

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Securities held to maturity	$ 437,193,000	$ 287,904,000
Preferred stock, par value (in dollars per share)	$ 1
Preferred stock authorized (in shares)	10,000,000
Preferred stock liquidation preference (in dollars per share)	$ 25,000
Preferred stock issued (in shares)	4,000	0
Preferred stock outstanding (in shares)	4,000	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock authorized (in shares)	150,000,000	150,000,000
Common stock issued (in shares)	86,675,279	79,013,729
Common stock outstanding (in shares)	86,675,279	79,013,729
Common stock issuable (in shares)	600,834	664,640

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest revenue:
Loans, including fees	$ 494,212	$ 476,039	$ 420,383
Investment securities:
Taxable	55,031	69,920	73,496
Tax exempt	7,043	4,564	4,189
Deposits in banks and short-term investments	1,710	2,183	2,012
Total interest revenue	557,996	552,706	500,080
Interest expense:
Deposits	41,772	66,856	39,543
Short-term borrowings	3	838	1,112
Federal Home Loan Bank advances	28	2,697	6,345
Long-term debt	14,434	12,921	14,330
Total interest expense	56,237	83,312	61,330
Net interest revenue	501,759	469,394	438,750
Provision for credit losses	80,434	13,150	9,500
Net interest revenue after provision for credit losses	421,325	456,244	429,250
Noninterest income:
Wealth management fees	9,240	6,150	5,191
Gains from other loan sales, net	5,420	6,867	9,277
Securities gains (losses), net	748	(1,021)	(656)
Other	32,213	28,775	24,142
Total noninterest income	156,109	104,713	92,961
Total revenue	577,434	560,957	522,211
Noninterest expenses:
Salaries and employee benefits	224,060	196,440	181,015
Occupancy	25,791	23,350	22,781
Communications and equipment	27,149	24,613	21,277
Professional fees	18,032	17,028	15,540
Lending and loan servicing expense	10,993	9,416	8,697
Outside services - electronic banking	7,513	7,020	6,623
Postage, printing and supplies	6,779	6,370	6,416
Advertising and public relations	15,203	6,170	5,991
FDIC assessments and other regulatory charges	5,982	4,901	8,491
Amortization of intangibles	4,168	4,938	6,846
Merger-related and other charges	7,018	6,907	5,414
Other	15,301	15,092	17,194
Total noninterest expenses	367,989	322,245	306,285
Income before income taxes	209,445	238,712	215,926
Income tax expense	45,356	52,991	49,815
Net income	164,089	185,721	166,111
Net income available to common shareholders	$ 159,269	$ 184,346	$ 164,927
Income per common share:
Basic (in dollars per share)	$ 1.91	$ 2.31	$ 2.07
Diluted (in dollars per share)	$ 1.91	$ 2.31	$ 2.07
Weighted average common shares outstanding:
Basic (in shares)	83,184	79,700	79,662
Diluted (in shares)	83,248	79,708	79,671
Service charges and fees
Noninterest income:
Service charges and other related fees	$ 32,401	$ 36,797	$ 35,997
Mortgage loan gains and related fees
Noninterest income:
Service charges and other related fees	$ 76,087	$ 27,145	$ 19,010

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income, Before-tax Amount	$ 209,445	$ 238,712	$ 215,926
Net income, Tax (Expense) Benefit	(45,356)	(52,991)	(49,815)
Net income	164,089	185,721	166,111
Unrealized gains (losses) on available-for- sale securities:
Unrealized holding gains (losses) arising during period, Before-tax Amount	39,385	64,749	(24,990)
Unrealized holding gains (losses) arising during period, Tax (Expense) Benefit	(9,514)	(15,696)	6,081
Unrealized holding gains (losses) arising during period, Net of Tax Amount	29,871	49,053	(18,909)
Reclassification adjustment for losses (gains) recognized in net income, Before-tax Amount	(748)	1,021	656
Reclassification adjustment for losses (gains) recognized in net income, Tax (Expense) Benefit	191	(247)	(132)
Reclassification adjustment for losses (gains) recognized in net income, Net of Tax Amount	(557)	774	524
Net unrealized gains (losses), Before-tax Amount	38,637	65,770	(24,334)
Net unrealized gains (losses), Tax (Expense) Benefit	(9,323)	(15,943)	5,949
Net unrealized gains (losses), Net of Tax Amount	29,314	49,827	(18,385)
Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Before-tax Amount	723	383	739
Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Tax (Expense) Benefit	(173)	(92)	(180)
Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Net of Tax Amount	550	291	559
Derivative instruments designated as cash flow hedges:
Amortization of losses included in net income on terminated derivative financial instruments previously accounted for as cash flow hedges, Before-tax Amount	0	337	499
Amortization of losses included in net income on terminated derivative financial instruments previously accounted for as cash flow hedges, Tax (Expense) Benefit	0	(86)	(129)
Amortization of losses included in net income on terminated derivative financial instruments previously accounted for as cash flow hedges, Net of Tax Amount	0	251	370
Unrealized holding losses on derivatives arising during the period, Before-tax Amount	(149)	0	0
Unrealized holding losses on derivatives arising during the period, Tax (Expense) Benefit	38	0	0
Unrealized holding losses on derivatives arising during the period, Net of Tax Amount	(111)	0	0
Reclassification of losses on derivative instruments realized in net income, Before-tax Amount	359	0	0
Reclassification of losses on derivative instruments realized in net income, Tax (Expense) Benefit	(91)	0	0
Reclassification of losses on derivative instruments realized in net income, Net of Tax Amount	268	0	0
Net cash flow hedge activity, Before-tax Amount	210	337	499
Net cash flow hedge activity, Tax (Expense) Benefit	(53)	(86)	(129)
Net cash flow hedge activity, Net of Tax Amount	157	251	370
Defined benefit pension plan activity:
Termination of defined benefit pension plan, Before-tax Amount	0	1,558	0
Termination of defined benefit pension plan, Tax (Expense) Benefit	0	(398)	0
Termination of defined benefit pension plan, Net of Tax Amount	0	1,160	0
Amendments to defined benefit pension plan, Before-tax Amount	0	(386)	(413)
Amendments to defined benefit pension plan, Tax (Expense) Benefit	0	99	105
Amendments to defined benefit pension plan, Net of Tax Amount	0	(287)	(308)
Net actuarial gain (loss) on defined benefit pension plans, Before-tax Amount	(1,804)	(2,390)	1,015
Net actuarial gain (loss) on defined benefit pension plans, Tax (Expense) Benefit	461	610	(259)
Net actuarial gain (loss) on defined benefit pension plans, Net of Tax Amount	(1,343)	(1,780)	756
Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plans, Before-tax Amount	857	699	907
Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plans, Tax (Expense) Benefit	(219)	(178)	(247)
Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plans, Net of Tax Amount	638	521	660
Net defined benefit pension plan activity, Before-tax Amount	(947)	(519)	1,509
Net defined benefit pension plan activity, Tax (Expense) Benefit	242	133	(401)
Net defined benefit pension plan activity, Net of Tax Amount	(705)	(386)	1,108
Total other comprehensive income (loss), Before-tax Amount	38,623	65,971	(21,587)
Total other comprehensive income (loss), Tax (Expense) Benefit	(9,307)	(15,988)	5,239
Total other comprehensive income (loss), Net of Tax Amount	29,316	49,983	(16,348)
Comprehensive income, Before-tax Amount	248,068	304,683	194,339
Comprehensive income, Tax (Expense) Benefit	(54,663)	(68,979)	(44,576)
Comprehensive income, Net of Tax Amount	$ 193,405	$ 235,704	$ 149,763

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Adoption of new accounting standard	Preferred Stock	Common Stock	Common Stock Issuable	Capital Surplus	Retained Earnings (Accumulated Deficit)	Retained Earnings (Accumulated Deficit)Adoption of new accounting standard	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2017	$ 1,303,334		$ 0	$ 77,580	$ 9,083	$ 1,451,814	$ (209,902)		$ (25,241)
Beginning balance (shares) at Dec. 31, 2017				77,579,561
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	166,111						166,111
Other comprehensive income (loss)	(16,348)								(16,348)
Common stock issued for acquisitions	$ 45,746			$ 1,444		44,302
Common stock issued for acquisitions (shares)				1,443,987
Purchases of common stock (shares)	0
Common stock dividends	$ (46,628)						(46,628)
Impact of equity-based compensation awards	4,211			$ 137	1,931	2,143
Impact of equity-based compensation awards (shares)				137,067
Impact of other United sponsored equity plans	1,128			$ 73	(270)	1,325
Impact of other United sponsored equity plans (shares)				73,462
Ending balance at Dec. 31, 2018	1,457,554	$ (549)	0	$ 79,234	10,744	1,499,584	(90,419)	$ (549)	(41,589)
Ending balance (shares) at Dec. 31, 2018				79,234,077
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	185,721						185,721
Other comprehensive income (loss)	49,983								49,983
Purchases of common stock	$ (13,020)			$ (500)		(12,520)
Purchases of common stock (shares)	(500,495)			(500,495)
Common stock dividends	$ (54,601)						(54,601)
Impact of equity-based compensation awards	8,130			$ 122	1,476	6,532
Impact of equity-based compensation awards (shares)				122,100
Impact of other United sponsored equity plans	2,474			$ 158	(729)	3,045
Impact of other United sponsored equity plans (shares)				158,047
Ending balance at Dec. 31, 2019	1,635,692	$ (3,529)	0	$ 79,014	11,491	1,496,641	40,152	$ (3,529)	8,394
Ending balance (shares) at Dec. 31, 2019				79,013,729
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	164,089						164,089
Other comprehensive income (loss)	29,316								29,316
Issuance of preferred stock	96,422		96,422
Common stock issued for acquisitions	163,589			$ 8,131		155,458
Common stock issued for acquisitions (shares)				8,130,633
Purchases of common stock	$ (20,782)			$ (827)		(19,955)
Purchases of common stock (shares)	(826,482)			(826,482)
Preferred stock dividends	$ (3,533)						(3,533)
Common stock dividends	(60,310)						(60,310)
Impact of equity-based compensation awards	6,086			$ 202	1,120	4,764
Impact of equity-based compensation awards (shares)				202,437
Impact of other United sponsored equity plans	490			$ 155	(1,756)	2,091
Impact of other United sponsored equity plans (shares)				154,962
Ending balance at Dec. 31, 2020	$ 2,007,530		$ 96,422	$ 86,675	$ 10,855	$ 1,638,999	$ 136,869		$ 37,710
Ending balance (shares) at Dec. 31, 2020				86,675,279

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Common stock dividends (in dollars per share)	$ 0.72	$ 0.68	$ 0.58

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net income	$ 164,089	$ 185,721	$ 166,111
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	(8,586)	23,952	30,971
Provision for credit losses	80,434	13,150	9,500
Stock-based compensation	7,887	9,360	6,057
Deferred income tax expense	2,668	14,909	32,630
Securities (gains) losses, net	(748)	1,021	656
Gains from other loan sales, net	(5,420)	(6,867)	(9,277)
Changes in assets and liabilities:
(Increase) decrease in other assets and accrued interest receivable	(20,139)	(45,789)	13,195
(Decrease) increase in accrued expenses and other liabilities	(14,783)	(1,975)	3,772
(Increase) decrease in loans held for sale	(46,721)	(39,549)	16,391
Net cash provided by operating activities	158,681	153,933	270,006
Debt securities held-to-maturity:
Proceeds from maturities and calls	57,981	50,379	58,605
Purchases	(157,465)	(59,629)	(11,983)
Debt securities available-for-sale and equity securities with readily determinable fair values:
Proceeds from sales	40,625	352,106	168,891
Proceeds from maturities and calls	834,725	349,758	346,505
Purchases	(1,456,311)	(294,245)	(566,333)
Net increase in loans	(1,069,089)	(205,612)	(291,890)
Net cash received in (paid for) acquisitions	195,699	(19,545)	(56,800)
Purchases of premises and equipment	(18,462)	(20,944)	(17,617)
Proceeds from sales of premises and equipment	903	6,595	6,483
Proceeds from sale of other real estate owned	1,074	2,439	4,664
Other investing activities, net	(10,243)	1,916	0
Net cash (used in) provided by investing activities	(1,580,563)	163,218	(359,475)
Financing activities:
Net increase in deposits	2,534,471	151,401	727,839
Net decrease in short-term borrowings	0	0	(264,923)
Proceeds from Federal Home Loan Bank advances	5,000	1,625,000	2,860,000
Repayment of Federal Home Loan Bank advances	(134,121)	(1,785,000)	(3,204,003)
Repayment of long-term debt	0	(55,266)	(71,831)
Proceeds from issuance of long-term debt, net of issuance costs	98,552	0	98,188
Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans	1,317	2,193	679
Proceeds from exercise of stock options	0	212	142
Cash paid for shares withheld to cover payroll taxes upon vesting of restricted stock units	(3,119)	(1,686)	(1,998)
Repurchase of common stock	(20,782)	(13,020)	0
Proceeds from issuance of Series I preferred stock, net of issuance costs	96,422	0	0
Cash dividends on common stock	(58,912)	(53,044)	(41,634)
Cash dividends on preferred stock	(3,533)	0	0
Net cash provided by (used in) financing activities	2,515,295	(129,210)	102,459
Net change in cash and cash equivalents, including restricted cash	1,093,413	187,941	12,990
Cash and cash equivalents, including restricted cash, at beginning of year	515,206	327,265	314,275
Cash and cash equivalents, including restricted cash, at end of year	1,608,619	515,206	327,265
Cash paid during the period for:
Interest	59,967	85,973	56,830
Income taxes	$ 36,536	$ 33,776	$ 7,880

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies See the Glossary of Defined Terms at the beginning of this Report for terms used herein. The accounting principles followed by United and the methods of applying these principles conform with GAAP and with general practices within the banking industry. The following is a description of the significant policies. Organization and Basis of Presentation The Holding Company is a bank holding company subject to the regulation of the Board of Governors of the Federal Reserve whose principal business is conducted by its wholly-owned commercial bank subsidiary, United Community Bank (the “Bank”). United is subject to regulation under the BHC Act. The consolidated financial statements include the accounts of the Holding Company, the Bank and other wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The Bank is a Georgia state chartered commercial bank that serves both rural and metropolitan markets in Georgia, South Carolina, North Carolina, Tennessee and Florida and provides a full range of banking services. The Bank is insured and subject to the regulation of the FDIC and is also subject to the regulation of the GADBF. Use of Estimates In preparing the consolidated financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the dates of the balance sheet and revenue and expenses for the years then ended. Actual results could differ significantly from those estimates. Material estimates that are particularly susceptible to significant change are the determination of the ACL, the valuation of acquired loans, the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans, the valuation of goodwill and separately identifiable intangible assets associated with mergers and acquisitions, and the valuation of deferred tax assets. Operating Segments Operating segments are components of a business about which separate financial information is available and evaluated regularly by the chief operating decision maker in deciding how to allocate resources and assessing performance. Public companies are required to report certain financial information about operating segments in interim and annual financial statements. United’s community banking operations are divided among geographic regions and local community banks within those regions. Those regions and banks have similar economic characteristics and are therefore considered to be one operating segment. Additionally, management assessed other operating units to determine if they should be classified and reported as segments, including Mortgage, Wealth Management and Commercial Banking Solutions. Qualitatively, these business units are primarily operating in the same geographic footprint as the community banks and face many of the same customers as the community banks. While the chief operating decision maker does have some limited production information for these entities, that information is not complete since it does not include a full allocation of revenue, costs and capital from key corporate functions. The business units are currently viewed more as a product line extension of the community banks. However, management will continue to evaluate these business units for separate reporting as facts and circumstances change. Based on this analysis, United concluded that it has one operating and reportable segment. Cash and Cash Equivalents Cash equivalents include amounts due from banks, interest-bearing deposits in banks, federal funds sold, commercial paper, reverse repurchase agreements and short-term investments and are carried at cost. Federal funds are generally sold for one-day periods, interest-bearing deposits in banks are available on demand and commercial paper investments and reverse repurchase agreements mature within a period of less than 90 days. A portion of the cash on hand and on deposit with the Federal Reserve Bank of Atlanta was required to meet regulatory reserve requirements. Investment Securities Debt Securities: Debt securities are classified as held-to-maturity and carried at amortized cost when management has the positive intent and ability to hold them to maturity. Debt securities are classified as available-for-sale when they may be sold before maturity. Securities available-for-sale are carried at fair value, with unrealized holding gains and losses reported in other comprehensive income, net of tax. Interest income includes amortization of purchase premiums or discounts. Premiums and discounts on securities are generally amortized or accreted on the level-yield method without anticipating prepayments, except for mortgage-backed securities where prepayments are anticipated. Premiums on callable debt securities are amortized to their earliest call date. Gains and losses on sales are recorded on the trade date and determined using the specific identification method. Transfers of securities between categories are recorded at fair value at the date of transfer. Unrealized holding gains or losses associated with transfers of securities from available-for-sale to held-to-maturity are included in the balance of AOCI in the consolidated balance sheets. These unrealized holding gains or losses are amortized/accreted into income over the remaining life of the security as an adjustment to the yield in a manner consistent with the amortization or accretion of the original purchase premium or discount on the associated security. A debt security is placed on nonaccrual status at the time any principal or interest payments become 90 days delinquent. Interest accrued but not received for a security placed on nonaccrual is reversed against interest income. ACL - Held-to-Maturity Securities: Since the adoption of ASC 326, management measures current expected credit losses on held-to-maturity debt securities on a collective basis by major security type. Accrued interest receivable on held-to-maturity debt securities totaled $1.78 million at December 31, 2020 and was excluded from the estimate of credit losses. The estimate of current expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management classifies the held-to-maturity portfolio into the following major security types: U.S. Government agencies and GSEs, state and political subdivisions, residential mortgage-backed, agency and GSEs and commercial mortgage-backed, agency and GSEs. All of the residential and commercial mortgage-backed securities held by United as held-to-maturity are issued by U.S. Government agencies and GSEs. These securities are either explicitly or implicitly guaranteed by the U.S. government, are highly rated by major rating agencies and have a long history of no credit losses. The state and political subdivision securities are highly rated by major rating agencies. ACL - Available-For-Sale Securities: For available-for-sale debt securities in an unrealized loss position, United first assesses whether it intends to sell, or whether it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security's amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, United evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. Since the adoption of ASC 326, if the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an ACL is recorded for the credit loss, limited by the amount that the fair value is less than the amortized cost basis. Any amount of unrealized loss that has not been recorded through an ACL is recognized in other comprehensive income. Changes in the ACL are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the ACL when management believes the uncollectability of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. Accrued interest receivable on available-for-sale debt securities totaled $9.11 million at December 31, 2020 and was excluded from the estimate of credit losses. Equity securities: Equity securities are included in other assets on the consolidated balance sheets. Those with readily determinable fair values are carried at fair value with changes in fair value recognized in net income. Those without readily determinable fair values include, among others, FHLB stock held to meet FHLB requirements related to outstanding advances and CRA equity investments, including those where the returns are primarily derived from LIHTC. Our investment in FHLB stock, which totaled $13.3 million at December 31, 2020, is accounted for using the cost method of accounting. Our LIHTC investments are accounted for using the proportional amortization method of accounting for qualified affordable housing investments which results in the amortization being reported as a component of income tax expense. Our obligations related to unfunded commitments for our LIHTC investments are reported in other liabilities. Our other CRA investments are accounted for using the equity method of accounting. As conditions warrant, we review our investments for impairment and will adjust the carrying value of the investment if it is deemed to be impaired. Loans Held for Sale United has elected the fair value option for mortgage loans held for sale in order to reduce certain timing differences and match changes in fair values of the loans with changes in the fair value of derivative instruments used to economically hedge them. Loans and Leases Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at amortized cost. Amortized cost is the principal balance outstanding, net of purchase premiums and discounts and deferred fees and costs. Accrued interest receivable related to loans totaled $35.5 million at December 31, 2020 and was reported in accrued interest receivable on the consolidated balance sheets. Interest income is accrued on the unpaid principal balance. Loan origination fees, net of certain direct origination costs, are deferred and recognized in interest income using methods that approximate a level yield without anticipating prepayments. Equipment Financing Lease Receivables: Equipment financing lease receivables, which are classified as sales-type or direct financing leases, are recorded as the sum of the future minimum lease payments, initial deferred costs and, if applicable, estimated or contractual residual values less unearned income and security deposits. For lease receivables with a residual value, the determination of such value is derived from a variety of sources including equipment valuation services, appraisals, and publicly available market data on recent sales transactions on similar equipment. The length of time until contract termination, the cyclical nature of equipment values and the limited marketplace for re-sale of certain leased assets are important variables considered in making this determination. Interest income, which is included in loan interest revenue in the consolidated statements of income, is recognized as earned using the effective interest method. Direct fees and costs associated with the origination of leases are deferred and included as a component of equipment financing receivables. Net deferred fees or costs are recognized as an adjustment to interest income over the contractual life of the lease using the effective interest method. These lease agreements may include options to renew and for the lessee to purchase the leased equipment at the end of the lease term. United excludes sales taxes from consideration in these lease contracts. PCD Loans (CECL): In acquisitions, United may acquire loans, some of which have experienced more than insignificant credit deterioration since origination. In those cases, United will consider internal loan grades, delinquency status and other relevant factors in assessing whether purchased loans are PCD. PCD loans are recorded at their fair value at the acquisition date. An initial ACL is determined using the same methodology as other loans held for investment and recognized as an adjustment to the acquisition price of the asset; thus, the sum of the loan's purchase price and ACL becomes its initial amortized cost basis. The difference between the initial amortized cost basis and the par value of the loan is a noncredit discount or premium, which is amortized into interest income over the life of the loan. Subsequent to initial recognition, PCD loans are subject to the same interest income recognition and impairment model as non-PCD loans, with changes to the ACL recorded through provision expense. Upon adoption of ASC 326, loans that were designated as PCI loans under the Incurred Loss guidance were classified as PCD loans without reassessment. PCI Loans (Incurred Loss): Prior to the adoption of ASC 326 on January 1, 2020, purchased loans with evidence of credit deterioration since origination were accounted for pursuant to ASC Topic 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality . These PCI loans were recorded at their estimated fair value at date of purchase. After acquisition, further losses evidenced by decreases in expected cash flows were recognized by an increase in the ACL. PCI loans were aggregated into pools of loans based on common risk characteristics such as the type of loan, payment status, or collateral type. United estimated the amount and timing of expected cash flows for each purchased loan pool and the expected cash flows in excess of the amount paid were recorded as interest income over the remaining life of the pool (accretable yield). The excess of the pool’s contractual principal and interest over expected cash flows was not recorded (nonaccretable difference). Over the life of the loan pool, expected cash flows continued to be estimated. If the present value of expected cash flows was less than the carrying amount, a loss was recorded. If the present value of expected cash flows was greater than the carrying amount, it was recognized as part of future interest revenue. Nonaccrual Loans: The accrual of interest is generally discontinued when a loan becomes 90 days past due or when management believes, after considering economic and business conditions and collection efforts, that the principal or interest will not be collectable in the normal course of business. A loan may continue to accrue interest after 90 days if it is well collateralized and in the process of collection. Past due status is based on contractual terms of the loan. During 2020, United granted loan payment deferrals in accordance with the CARES Act and interagency guidance for certain borrowers experiencing temporary cash flow shortages as a result of the COVID-19 pandemic. During the temporary payment deferral period, these loans are not considered past due. All interest accrued but not received for loans placed on nonaccrual is reversed against interest income. Interest received on such loans is accounted for using the cost-recovery method, until qualifying for return to accrual. Under the cost-recovery method, interest income is not recognized until the loan balance is reduced to zero. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current, there is a sustained period of repayment performance and future payments are reasonably assured. TDRs: A loan for which the terms have been modified resulting in a more than insignificant concession, and for which the borrower is experiencing financial difficulties, is generally considered to be a TDR. Modified terms that result in a TDR include one or a combination of the following: a reduction of the stated interest rate of the loan, an extension of the amortization period that would not otherwise be considered in the current market for new debt with similar risk characteristics; a restructuring of the borrower’s debt into an “A/B note structure” in which the A note would fall within the borrower’s ability to pay and the remainder would be included in the B note; a mandated bankruptcy restructuring; or interest-only payment terms greater than 90 days where the borrower is unable to amortize the loan. Collateral dependent TDRs that subsequently default or are placed on nonaccrual are charged down to the fair value of the collateral consistent with United’s policy for nonaccrual loans. As discussed in Note 2, in accordance with the CARES Act, United implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. These loan modifications were not considered TDRs to the extent that the borrower was impacted by the COVID-19 pandemic and was not more than 30 days past due at December 31, 2019, or in certain circumstances, at the time that the COVID-19 loan modification program was implemented, unless the loan was previously classified as a TDR. Impaired Loans (Incurred Loss): With the exception of PCI loans, a loan is considered impaired when, based on current events and circumstances, it is probable that all amounts due, according to the contractual terms of the loan, will not be collected. Individually impaired loans are measured based on the present value of expected future cash flows, discounted at the loan’s effective interest rate, at the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent. Interest revenue on impaired loans is discontinued when the loans meet the criteria for nonaccrual status. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not considered impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and borrower, including the length of the delay, the reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest owed. PCI loans are considered to be impaired when it is probable that United will be unable to collect all the cash flows expected at acquisition, plus additional cash flows expected to be collected arising from changes in estimates after acquisition. Loans that are accounted for in pools are evaluated collectively for impairment on a pool by pool basis based on expected pool cash flows. Discounts continue to be accreted as long as there are expected future cash flows in excess of the current carrying amount of the specifically-reviewed loan or pool. Prior to the implementation of CECL, management individually evaluated certain impaired loans on a quarterly basis, including all non-PCI nonaccrual relationships with a balance of $500,000 or greater and all TDRs for impairment. Impairment for collateral dependent loans within this population is measured based on the fair value of the collateral. If impairment is identified, the loan is generally charged down to the fair value of the underlying collateral, less selling costs. Impairment for non-collateral dependent TDRs within this population is measured based on discounted cash flows or the loan’s observable market price. Impairment identified using these methods would result in the establishment of a specific reserve. Concentration of Credit Risk: Most of United’s business activity is with customers located within the markets where it has banking operations. Therefore, United’s exposure to credit risk is significantly affected by changes in the economy within its markets. Approximately 69% of United’s loan portfolio is secured by real estate and is therefore susceptible to changes in real estate valuations. ACL- Loans United implemented CECL upon adoption of ASC 326 on January 1, 2020. The following discussion provides a description of the methodology applied to calculate the ACL under CECL for 2020 and under the Incurred Loss method for periods prior to 2020. CECL: The ACL is a valuation account that is deducted from the loans' amortized cost basis to present the net amount expected to be collected on the loans. Loans are charged off against the ACL when management believes the uncollectability of a loan balance is confirmed. Accrued interest receivable is excluded from the estimate of credit losses. Management determines the ACL balance using relevant available information, from internal and external sources, relating to past events, current conditions, and reasonable and supportable forecasts. Historical credit behaviors along with model judgments provide the basis for the estimation of expected credit losses. Adjustments to modeled loss estimates may be made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, delinquency level, or term as well as for changes in environmental conditions, such as changes in economic conditions, property values, or other relevant factors. The ACL-loans is measured on a collective basis when similar risk characteristics exist. United has identified the following portfolio segments and calculates the ACL for each using a discounted cash flow methodology at the loan level, with loss rates, prepayment assumptions and curtailment assumptions driven by each loan’s collateral type: Owner occupied commercial real estate - Loans in this category are susceptible to business failure and general economic conditions. Income producing commercial real estate - Common risks for this loan category are declines in general economic conditions, declines in real estate value, declines in occupancy rates, and lack of suitable alternative use for the property. Commercial & industrial - Risks to this loan category include the inability to monitor the condition of the collateral, which often consists of inventory, accounts receivable and other non-real estate assets. Equipment and inventory obsolescence can also pose a risk. Declines in general economic conditions and other events can cause cash flows to fall to levels insufficient to service debt. Commercial construction - Risks common to commercial construction loans are cost overruns, changes in market demand for property, inadequate long-term financing arrangements and declines in real estate values. Equipment financing - Risks associated with equipment financing are similar to those described for commercial and industrial loans, including general economic conditions, as well as appropriate lien priority on equipment, equipment obsolescence and the general mobility of the collateral. Residential mortgage - Residential mortgage loans are susceptible to weakening general economic conditions, increases in unemployment rates and declining real estate values. Home equity lines of credit - Risks common to home equity lines of credit are general economic conditions, including an increase in unemployment rates, and declining real estate values that reduce or eliminate the borrower’s home equity. Residential construction - Residential construction loans are susceptible to the same risks as residential mortgage loans. Changes in market demand for property lead to longer marketing times resulting in higher carrying costs and declining values. Consumer - Risks common to consumer direct loans include unemployment and changes in local economic conditions as well as the inability to monitor collateral consisting of personal property. Indirect auto - Risks common to indirect auto loans include unemployment and changes in local economic conditions as well as the inability to monitor collateral. During 2019, United sold its portfolio of indirect auto loans. When management determines that foreclosure is probable or when the borrower is experiencing financial difficulty at the reporting date and repayment is expected to be provided substantially through the operation or sale of the collateral, expected credit losses are based on the fair value of the collateral at the reporting date, adjusted for selling costs as appropriate. When the discounted cash flow method is used to determine the ACL, management adjusts the effective interest rate used to discount expected cash flows to incorporate expected prepayments. The ACL on a TDR is measured using the same method as all other loans held for investment, except that the original interest rate is used to discount the expected cash flows, not the rate specified within the restructuring. Determining the Contractual Term: Expected credit losses are estimated over the contractual term of the loans, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals, and modifications unless either of the following applies: management has a reasonable expectation at the reporting date that a TDR will be executed with an individual borrower or the extension or renewal options are included in the original or modified contract at the reporting date and are not unconditionally cancellable by United. Incurred Loss ACL: Under the Incurred Loss method, the ACL represents an amount, which, in management’s judgment, is adequate to absorb probable losses on existing loans as of the date of the balance sheet. The Incurred Loss ACL is composed of general reserves, specific reserves, and PCI reserves. General reserves are determined by applying loss percentages to the individual loan categories that are based on actual historical loss experience. Additionally, the general economic and business conditions affecting key lending areas, credit quality trends, collateral values, loan volumes and concentrations, seasoning of the loan portfolio, the findings of internal and external credit reviews and results from external bank regulatory examinations are considered in this evaluation. The need for specific reserves was evaluated on nonaccrual loan relationships greater than $500,000 and all TDRs. The specific reserves were determined on a loan-by-loan basis based on management’s evaluation of United’s exposure for each credit, given the current payment status of the loan and the value of any underlying collateral. Loans for which specific reserves are provided are excluded from the calculation of general reserves. For PCI loans, a valuation allowance is established when it is probable that the Company will be unable to collect all the cash flows expected at acquisition plus additional cash flows expected to be collected arising from changes in estimate after acquisition. ACL - Off-Balance Sheet Credit Exposures Management estimates expected credit losses on commitments to extend credit over the contractual period during which United is exposed to credit risk on the underlying commitments. The ACL on off-balance sheet credit exposures is adjusted as a provision for credit loss expense. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated life. The ACL is calculated using the same aggregate reserve rates calculated for the funded portion of loans at the portfolio level applied to the amount of commitments expected to fund. Premises and Equipment Premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed primarily using the straight line method over the estimated useful lives of the related assets. Costs incurred for maintenance and repairs are expensed as incurred. The range of estimated useful lives for buildings and improvements is 10 to 40 years, for land improvements, 10 years, and for furniture and equipment, 3 to 10 years. United periodically reviews the carrying value of premises and equipment for impairment whenever events or circumstances indicate that the carrying amount of such assets may not be fully recoverable. Foreclosed Properties (Other Real Estate Owned) Foreclosed property is initially recorded at fair value, less cost to sell. If the fair value, less cost to sell at the time of foreclosure is less than the loan balance, the deficiency is recorded as a loan charge-off against the ACL. If the fair value, less cost to sell, of the foreclosed property decreases during the holding period, a valuation allowance is established with a charge to operating expenses. When the foreclosed property is sold, a gain or loss is recognized on the sale for the difference between the sales proceeds and the carrying amount of the property. Goodwill and Other Intangible Assets Goodwill is an asset representing the future economic benefits from other assets acquired that are not individually identified and separately recognized. Goodwill is measured as the excess of the consideration transferred, net of the fair value of identifiable assets acquired and liabilities assumed at the acquisition date. Goodwill is not amortized, but instead is tested for impairment annually or more frequently if events or circumstances exist that indicate a goodwill impairment test should be performed. Other intangible assets, which are initially recorded at fair value, consist of core deposit intangible assets and noncompete agreements resulting from acquisitions. Core deposit intangible assets are amortized on a sum-of-the-years-digits basis over their estimated useful lives. Noncompete agreements, which were fully amortized at December 31, 2019, were amortized on a straight line basis over their estimated useful lives. Management evaluates other intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of the asset may not be recoverable. Transfers of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been relinquished. Control over transferred assets is deemed to be surrendered when the assets have been isolated from United, the transferee obtains the right, free of conditions that constrain it from taking advantage of that right, to pledge or exchange the transferred assets and United does not maintain effective control over the transferred assets through an agreement to repurchase them before maturity. Servicing Rights United records a separate servicing asset for SBA loans, USDA loans, and residential mortgage loans when the loan is sold but servicing is retained. This asset represents the right to service the loans and receive a fee in compensation. Servicing assets are initially recorded at their fair value as a component of the sale proceeds. The fair value of the servicing assets is based on an analysis of discounted cash flows that incorporates estimates of (1) market servicing costs, (2) market-based prepayment rates, and (3) market profit margins. Servicing assets are included in other assets. United has elected to subsequently measure the servicing assets for government guaranteed loans and residential mortgage loans at fair value. The rate of prepayment of loans serviced is the most significant estimate involved in the measurement process. Estimates of prepayment rates are based on market expectations of future prepayment rates, industry trends, and other considerations. Actual prepayment rates will differ from those projected by management due to changes in a variety of economic factors, including prevailing interest rates and the availability of alternative financing sources to borrowers. If actual prepayments of the loans being serviced were to occur more quickly than projected, the carrying value of servicing assets might have to be written down through a charge to earnings in the current period. If actual prepa

Accounting Standards Updates an

Accounting Standards Updates and Recently Adopted Standards	12 Months Ended
	Dec. 31, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
Accounting Standards Updates and Recently Adopted Standards	Accounting Standards Updates and Recently Adopted Standards Recently Adopted Standards On January 1, 2020, United adopted ASC 326 , which replaced the Incurred Loss framework in prior GAAP with a CECL framework. The CECL framework requires an estimate of expected credit losses for the remaining estimated life of the financial asset using historical experience, current conditions, and reasonable and supportable forecasts and generally applies to financial assets measured at amortized cost, including loan receivables and held-to-maturity debt securities, and some off-balance sheet credit exposures such as unfunded commitments to extend credit. Financial assets measured at amortized cost will be presented at the net amount expected to be collected by using an ACL. PCD loans will receive an initial allowance at the acquisition date that represents an adjustment to the amortized cost basis of the loan, with no impact to earnings. Credit losses relating to available-for-sale debt securities will be recorded through an ACL prospectively, with such allowance limited to the amount by which fair value is below amortized cost. United adopted ASC 326 as of January 1, 2020 using the modified retrospective method for loans, leases and off-balance sheet credit exposures. Adoption of this guidance resulted in an $8.75 million increase in the ACL, comprised of increases in the ACL for loans of $6.88 million and the ACL for unfunded commitments of $1.87 million, with $3.59 million of the increase reclassified from the amortized cost basis of PCD financial assets. The cumulative effect adjustment to retained earnings was $3.53 million, net of tax. Calculated credit losses on held-to-maturity debt securities were not material and there was no impact to the available-for-sale securities portfolio or other financial instruments. Results for reporting periods beginning after January 1, 2020 are presented under ASC 326 while prior period amounts continue to be reported in accordance with Incurred Loss. The ACL for the majority of loans and leases was calculated using a discounted cash flow methodology applied at a loan level with a one-year reasonable and supportable forecast period and a two-year straight-line reversion period. In connection with the adoption, management has implemented changes to relevant systems, processes and controls where necessary. United’s CECL allowance will fluctuate over time due to macroeconomic conditions and forecasts as well as the size and composition of the loan portfolios. United has adopted the relief provided by federal banking regulatory agencies for the delay of the adverse capital impact of CECL at adoption and during the subsequent two-year period following adoption. This optional two-year delay is followed by an optional three-year transition period to phase out the aggregate amount of capital benefit provided during the initial two-year delay. Under the transition provision, the amount of aggregate capital benefit is phased out by 25% each year with the full impact of adoption completely recognized by the beginning of the sixth year. United adopted ASC 326 using the prospective transition approach for PCD assets that were previously classified as PCI. In accordance with the standard, management did not reassess whether PCI assets met the criteria of PCD assets as of the date of adoption. As mentioned above, the amortized cost basis of the PCD assets was adjusted to reflect the addition of $3.59 million to the ACL. The remaining noncredit discount (based on the adjusted amortized cost basis) is being accreted into interest income at a rate that approximates the effective interest rate beginning on January 1, 2020. With regard to PCD assets, because United elected to disaggregate the former PCI pools and no longer considers these pools to be the unit of account, contractually delinquent PCD loans are now being reported as nonaccrual loans using the same criteria as other loans. Similarly, although management did not reassess whether modifications to individual acquired financial assets accounted for in pools were TDRs as of the date of adoption, PCD loans that are restructured and meet the definition of TDR after the adoption of ASC 326 are being reported as such. In addition to the aforementioned elections, United made the following elections at adoption: • not to measure an ACL for accrued interest receivable and instead elected to reverse interest income on those loans that are 90 days past due; • to exclude accrued interest receivable from the amortized cost basis of financial instruments subject to ASC 326 and to separately state the balance of accrued interest receivable on the consolidated balance sheet; • to adjust the discount rate used to calculate credit losses for expected prepayments and is including all changes in discounted cash flows as credit loss; and • as a practical expedient, elected to use the fair value of collateral when determining the ACL for loans if repayment is expected to be provided substantially through the operation or sale of the collateral when the borrower is experiencing financial difficulty (collateral-dependent loans). On March 27, 2020, the CARES Act was signed into law, with certain relief extended in December 2020 by the Consolidated Appropriations Act, 2021. Additional COVID-19 pandemic relief was granted by the bank regulatory agencies through a series of interagency statements issued during 2020. The CARES Act, as extended, and the interagency statements include a number of provisions that were applicable to United, including the following: • Accounting Relief for TDRs : The CARES Act provides that modifications under certain forbearance conditions for loans that were not more than 30 days past due at December 31, 2019 will not be considered TDRs for regulatory reporting and GAAP. This exemption period ends on the earlier of January 1, 2022 or the date that is 60 days after the termination date of the national emergency. The interagency statements provide additional relief from TDR status for certain short-term deferrals related to the COVID-19 pandemic for borrowers that were current at the time a modification program was implemented or at the time of the modification itself. • Optional Delay and Regulatory Relief for ASC 326 Adoption : The CARES Act stipulates that large SEC filers have the option of delaying the adoption of ASC 326 from January 1, 2020 to the earlier of the end of the COVID-19 emergency period or December 31, 2020. Banks that were required to implement ASC 326 by the end of 2020 were granted the option to defer any impact on regulatory capital for two years before beginning the original three-year regulatory phase-in period, for a total five-year phase-in period. Although United did not elect to delay the adoption of ASC 326, the Company elected the five-year phase-in period for regulatory capital purposes, as discussed above. • PPP : The CARES Act creates the PPP through the SBA, which allowed United to lend money to small businesses to maintain employee payrolls and pay other qualified expenses during the crisis with guarantees from the SBA. Under this program, loan amounts may be forgiven if the proceeds are used for payroll and other permitted expenses in accordance with the requirements of the PPP. In March 2020, the FASB issued ASU No. 2020-03, Codification Improvements to Financial Instruments . This update clarified certain minor issues within the codification, including, among other things, debt securities disclosure for financial institutions and determination of the contractual term of a net investment in a lease. The standard was effective immediately, and did not have a material impact on the consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting . This update, the scope of which was clarified with ASU No. 2021-01 in January of 2021, provides expedients for contracts that are modified because of reference rate reform, including receivables, debt, leases, and certain derivatives. In addition, the update provides a one-time election to sell or transfer debt securities classified as held-to-maturity that reference a rate that is affected by reference rate reform. The update is effective as of March 12, 2020 through December 31, 2022. At the time of adoption, there was no material impact on the consolidated financial statements, although United anticipates optional expedients adopted such as contract modification and hedge accounting will provide relief otherwise not provided through December 31, 2022. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825 Financial Instruments . In addition to amending guidance related to the new CECL standard, this update clarifies certain aspects of hedge accounting and recognition and measurement of financial instruments. United adopted this update as of January 1, 2020, with no material impact on the consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . This update eliminates Step 2 from the goodwill impairment test, which required an entity to calculate the implied fair value of goodwill by valuing a reporting unit’s assets and liabilities using the same process that would be required to value assets and liabilities in a business combination. Instead, the amendments require that an entity perform its annual goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. United adopted this update as of January 1, 2020, with no material impact on the consolidated financial statements. Accounting Standards Updates Not Yet Adopted as of December 31, 2020 In October 2020, the FASB issued ASU No. 2020-10, Codification Improvements . In addition to consolidating existing disclosure guidance into a single codification section to reduce the likelihood of a required disclosure being missed, this update clarifies the application of select guidance in cases where the original guidance may have been unclear. Adoption of this update, which is effective for United as of January 1, 2021, is not expected to have a material impact on the consolidated financial statements. In October 2020, the FASB issued ASU No. 2020-08, Codification Improvements to Subtopic 310-20, Receivables—Nonrefundable Fees and Other Costs . This update clarifies that an entity should reevaluate whether a callable debt security meets the criteria to adjust the amortization period of any related premium at each reporting period. Adoption of this update, which is effective for United as of January 1, 2021, is not expected to have a material impact on the consolidated financial statements. In January 2020, the FASB issued ASU No. 2020-01, Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)—Clarifying the Interactions between Topic 321, Topic 323, and Topic 815 (a consensus of the Emerging Issues Task Force) . This update clarifies whether an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting for the purposes of applying the measurement alternative and how to account for certain forward contracts and purchased options to purchase securities. For public entities, this guidance is effective for fiscal years beginning after December 15, 2020. United does not expect the new guidance to have a material impact on the consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes . This update removes several exceptions related to intraperiod tax allocation when there is a loss from continuing operations and income from other items, foreign subsidiaries becoming equity method investments and vice versa, and calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. The guidance also amends requirements related to franchise tax that is partially based on income, a step up in the tax basis of goodwill, allocation of consolidated tax expense to a legal entity not subject to tax in its separate financial statements, the effects of enacted changes in tax laws and other minor codification improvements regarding employee stock ownership plans and investments in qualified affordable housing projects. For public entities, this guidance is effective for fiscal years beginning after December 15, 2020. United does not expect the new guidance to have a material impact on the consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans . The update removes disclosures that are no longer considered cost beneficial, clarifies specific requirements of disclosures, and adds disclosure requirements identified as relevant. For public entities, this guidance is effective for fiscal years ending after December 15, 2020 and requires retrospective application to prior periods presented. United does not expect the new guidance to have a material impact on the consolidated financial statements.

Mergers and Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Mergers and Acquisitions	Mergers and Acquisitions Acquisition of Three Shores On July 1, 2020, United completed the acquisition of Three Shores, including its wholly-owned subsidiary, Seaside, headquartered in Orlando, Florida. Seaside operated a 14-branch network located in key Florida metropolitan markets. In connection with the acquisition, United acquired $2.13 billion of assets and assumed $1.99 billion of liabilities. Under the terms of the merger agreement, Three Shores shareholders received $188 million in total consideration, of which $164 million was United common stock and $24.1 million was cash. United issued 8.13 million shares of common stock to Three Shores shareholders in the acquisition. The fair value of consideration paid exceeded the fair value of the identifiable assets and liabilities acquired and resulted in the establishment of goodwill in the amount of $40.4 million, representing the intangible value of Three Shores’ business and reputation within the markets it served. None of the goodwill is expected to be deductible for income tax purposes. United will amortize the related core deposit intangible of $3.36 million using the sum-of-the-years-digits method over 10 years, which represents the expected useful life of the asset. United’s operating results for the year ended December 31, 2020 include the operating results of the acquired business for the period subsequent to the acquisition date of July 1, 2020. The acquisition of Three Shores has been accounted for as a business combination. Accordingly, the assets acquired and liabilities assumed are presented at their fair values as of the acquisition date. The determination of fair value requires management to make estimates about discount rates, future expected cash flows, market conditions and other future events that are highly subjective in nature and subject to change. Fair values are preliminary and are subject to refinement for a period not to exceed one year after the closing date of an acquisition as information relative to closing date fair values becomes available. During the fourth quarter of 2020, within the one-year measurement period, United received additional information regarding acquisition date money market fund balances held by third party investment brokers and accrued interest receivable on certain debt securities and loans. As a result, the provisional fair values assigned to acquired cash and cash equivalents and accrued interest receivable increased by $1.09 million and $116,000, respectively. As a result of these adjustments, goodwill was reduced by $1.21 million. These adjustments are reflected in the fair values presented in the table below. The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 219,807 Debt securities 381,740 Loans 1,427,966 Premises and equipment, net 1,584 Accrued interest receivable 7,681 Derivative assets 11,800 Net deferred tax asset 15,061 Core deposit intangible 3,360 Other assets 65,340 Total assets acquired 2,134,339 Liabilities Deposits 1,802,694 FHLB advances and long-term debt 144,121 Derivative liabilities 12,165 Other liabilities 28,046 Total liabilities assumed 1,987,026 Total identifiable net assets 147,313 Consideration transferred Cash 24,108 Common stock issued (8,130,633 shares) 163,589 Total fair value of consideration transferred 187,697 Goodwill $ 40,384 The following table presents additional information related to the acquired loan portfolio at the acquisition date (in thousands) : July 1, 2020 PCD loans: Par Value $ 283,137 ACL at acquisition (11,152) Non-credit discount (8,694) Purchase price $ 263,291 Non-PCD loans: Fair value $ 1,164,675 Gross contractual amounts receivable 1,358,793 Estimate of contractual cash flows not expected to be collected 76,503 Acquisition of FMBT On May 1, 2019, United completed the acquisition of FMBT. FMBT operated four banking offices in Athens-Clarke County, Georgia. In connection with the acquisition, United acquired $245 million of assets and assumed $213 million of liabilities. Under the terms of the merger agreement, FMBT shareholders received $52.1 million in cash. The fair value of consideration paid exceeded the fair value of the identifiable assets and liabilities acquired and resulted in the establishment of goodwill in the amount of $20.3 million, representing the intangible value of FMBT’s business and reputation within the markets it served. None of the goodwill recognized is expected to be deductible for income tax purposes. United is amortizing the related core deposit intangible of $2.80 million using the sum-of-the-years-digits method over 9.25 years, which represents the expected useful life of the asset. The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 32,548 Loans 192,494 Premises and equipment, net 8,524 BOLI 6,823 Net deferred tax asset 157 Core deposit intangible 2,800 Other assets 1,278 Total assets acquired 244,624 Liabilities Deposits 212,127 Other liabilities 717 Total liabilities assumed 212,844 Total identifiable net assets 31,780 Cash consideration transferred 52,093 Goodwill $ 20,313 The following table presents additional information related to the acquired loan portfolio at the acquisition date (in thousands) : May 1, 2019 PCI loans: Contractually required principal and interest $ 13,145 Non-accretable difference 2,517 Cash flows expected to be collected 10,628 Accretable yield 1,300 Fair value $ 9,328 Non-PCI loans: Fair value $ 183,166 Gross contractual amounts receivable 218,855 Estimate of contractual cash flows not expected to be collected 8,826 Acquisition of Navitas On February 1, 2018, United completed the acquisition of Navitas, a specialty lending company providing equipment finance credit services to small and medium-sized businesses nationwide. In connection with the acquisition, United acquired $393 million of assets and assumed $350 million of liabilities. Under the terms of the merger agreement, Navitas shareholders received $130 million in total consideration, of which $84.5 million was paid in cash and $45.7 million was paid in United common stock. The fair value of consideration paid exceeded the fair value of the identifiable assets and liabilities acquired and resulted in the establishment of goodwill in the amount of $87.4 million, representing the intangible value of Navitas’ business and reputation within the markets it served. None of the goodwill recognized is expected to be deductible for income tax purposes. The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 27,700 Loans and leases, net 358,352 Premises and equipment, net 324 Net deferred tax asset 2,873 Other assets 4,051 Total assets acquired 393,300 Liabilities Short-term borrowings 214,923 Long-term debt 119,402 Other liabilities 16,108 Total liabilities assumed 350,433 Total identifiable net assets 42,867 Consideration transferred Cash 84,500 Common stock issued (1,443,987 shares) 45,746 Total fair value of consideration transferred 130,246 Goodwill $ 87,379 The following table presents additional information related to the acquired loan and lease portfolio at the acquisition date (in thousands) . February 1, 2018 PCI loans: Contractually required principal and interest $ 24,711 Non-accretable difference 5,505 Cash flows expected to be collected 19,206 Accretable yield 1,977 Fair value $ 17,229 Non-PCI loans: Fair value $ 341,123 Gross contractual amounts receivable 389,432 Estimate of contractual cash flows not expected to be collected 8,624 In January 2018, after announcement of its intention to acquire Navitas but prior to the completion of the acquisition, United purchased $19.9 million in loans from Navitas in a transaction separate from the business combination. Pro forma information - unaudited The following table discloses the impact of the mergers with Three Shores, FMBT, and Navitas, since the respective acquisition dates through December 31 of the year of acquisition. The table also presents certain pro forma information as if Three Shores had been acquired January 1, 2019, FMBT had been acquired on January 1, 2018 and Navitas had been acquired on January 1, 2017. These results combine the historical results of the acquired entities with United’s consolidated statements of income and, while adjustments were made for the estimated impact of certain fair value adjustments and other acquisition-related activity, they are not necessarily indicative of what would have occurred had the acquisitions taken place in earlier years. For purposes of pro forma information, merger-related costs incurred in the year of acquisition are excluded from the actual acquisition year results and included in the pro forma acquisition year results. As a result, merger-related costs related to the acquisition of Three Shores of $5.04 million are reflected in 2019 pro forma information and merger-related costs related to the acquisition of FMBT of $2.02 million are reflected in 2018 pro forma information. Merger-related costs related to the acquisition of Navitas of $4.98 million were previously reported in 2017 pro forma information, which is not presented in the following table. The following table presents the actual results and pro forma information for the periods indicated (in thousands) . (Unaudited) Year Ended December 31, Revenue Net Income 2020 Actual Three Shores results included in statement of income since acquisition date $ 24,541 $ 6,800 Supplemental consolidated pro forma as if Three Shores had been acquired January 1, 2019 597,729 168,717 2019 Actual FMBT results included in statement of income since acquisition date $ 7,525 $ 4,053 Supplemental consolidated pro forma as if Three Shores had been acquired on January 1, 2019 and FMBT had been acquired January 1, 2018 636,079 210,232 2018 Actual Navitas results included in the statement of income since acquisition date $ 24,285 $ 7,149 Supplemental consolidated pro forma as if FMBT had been acquired January 1, 2018 and Navitas had been acquired January 1, 2017 539,152 171,218

Cash Flows

Cash Flows	12 Months Ended
	Dec. 31, 2020
Supplemental Cash Flow Elements [Abstract]
Cash Flows	Cash Flows During 2020, 2019 and 2018, loans having a value of $822,000, $1.17 million and $3.02 million, respectively, were transferred to foreclosed property. United accounts for sales of SBA/USDA loans on the trade date. At December 31, 2020 United had no unsettled sales of SBA/USDA loans. At December 31, 2019 and 2018, United had unsettled sales of SBA/USDA loans of $8.19 million and $32.9 million, respectively. During 2020, United acquired, through a business combination, assets with a fair value totaling $2.17 billion and liabilities with a fair value totaling $1.99 billion, for net assets acquired of $188 million. Common stock issued pursuant to this business combination totaled $164 million. During 2019, United acquired, through a business combination, assets with a fair value totaling $265 million and liabilities with a fair value totaling $213 million, for net assets acquired of $52.1 million.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities At December 31, 2020 and 2019, securities with a carrying value of $1.11 billion and $918 million, respectively, were pledged to secure public deposits, derivatives and other secured borrowings. The cost basis, unrealized gains and losses, and fair value of debt securities held-to-maturity as of the dates indicated are as follows (in thousands) : Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value As of December 31, 2020 U.S. Government agencies & GSEs $ 10,575 $ 26 $ 11 $ 10,590 State and political subdivisions 197,723 7,658 242 205,139 Residential mortgage-backed, Agency & GSE 113,400 4,774 1 118,173 Commercial mortgage-backed, Agency & GSE 98,663 4,874 246 103,291 Total $ 420,361 $ 17,332 $ 500 $ 437,193 As of December 31, 2019 State and political subdivisions $ 45,479 $ 1,574 $ 9 $ 47,044 Residential mortgage-backed, Agency & GSE 153,967 2,014 694 155,287 Commercial mortgage-backed, Agency & GSE 84,087 1,627 141 85,573 Total $ 283,533 $ 5,215 $ 844 $ 287,904 The cost basis, unrealized gains and losses, and fair value of debt securities available-for-sale as of the dates indicated are as follows (in thousands): Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value As of December 31, 2020 U.S. Treasuries $ 123,677 $ 4,395 $ — $ 128,072 U.S. Government agencies & GSEs 152,596 701 325 152,972 State and political subdivisions 253,630 20,891 49 274,472 Residential mortgage-backed, Agency & GSE 1,275,551 29,107 766 1,303,892 Residential mortgage-backed, Non-agency 174,322 7,499 128 181,693 Commercial mortgage-backed, Agency & GSE 524,852 8,013 597 532,268 Commercial mortgage-backed, Non-agency 15,350 1,513 — 16,863 Corporate bonds 70,057 1,711 1 71,767 Asset-backed securities 562,076 1,278 632 562,722 Total $ 3,152,111 $ 75,108 $ 2,498 $ 3,224,721 As of December 31, 2019 U.S. Treasuries $ 152,990 $ 1,628 $ — $ 154,618 U.S. Government agencies & GSEs 2,848 188 1 3,035 State and political subdivisions 214,677 11,813 — 226,490 Residential mortgage-backed, Agency & GSE 1,030,948 12,022 726 1,042,244 Residential mortgage-backed, Non-agency 250,550 6,231 — 256,781 Commercial mortgage-backed, Agency & GSE 266,770 2,261 128 268,903 Commercial mortgage-backed, Non-agency 15,395 918 263 16,050 Corporate bonds 202,131 1,178 218 203,091 Asset-backed securities 104,298 743 1,672 103,369 Total $ 2,240,607 $ 36,982 $ 3,008 $ 2,274,581 At year-end 2020 and 2019, there were no holdings of debt obligations of any one issuer, other than the U.S. Government and its agencies, in an amount greater than 10% of shareholders’ equity. The following summarizes debt securities held-to-maturity in an unrealized loss position as of the dates indicated (in thousands) : Less than 12 Months 12 Months or More Total Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized As of December 31, 2020 U.S. Government agencies & GSEs $ 4,677 $ 11 $ — $ — $ 4,677 $ 11 State and political subdivisions 14,870 242 — — 14,870 242 Residential mortgage-backed, Agency & GSE 999 1 — — 999 1 Commercial mortgage-backed, Agency & GSE 24,956 236 1,352 10 26,308 246 Total unrealized loss position $ 45,502 $ 490 $ 1,352 $ 10 $ 46,854 $ 500 As of December 31, 2019 State and political subdivisions $ 10,117 $ 9 $ — $ — $ 10,117 $ 9 Residential mortgage-backed, Agency & GSE 16,049 64 48,237 630 64,286 694 Commercial mortgage-backed, Agency & GSE 21,841 87 1,685 54 23,526 141 Total unrealized loss position $ 48,007 $ 160 $ 49,922 $ 684 $ 97,929 $ 844 The following summarizes debt securities available-for-sale in an unrealized loss position as of the dates indicated (in thousands) : Less than 12 Months 12 Months or More Total Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized As of December 31, 2020 U.S. Government agencies & GSEs $ 27,952 $ 324 $ 607 $ 1 $ 28,559 $ 325 State and political subdivisions 9,402 49 — — 9,402 49 Residential mortgage-backed, Agency & GSE 232,199 766 — — 232,199 766 Residential mortgage-backed, Non-agency 2,331 128 — — 2,331 128 Commercial mortgage-backed, Agency & GSE 89,918 597 — — 89,918 597 Corporate bonds 1,410 1 — — 1,410 1 Asset-backed securities 87,305 28 53,587 604 140,892 632 Total unrealized loss position $ 450,517 $ 1,893 $ 54,194 $ 605 $ 504,711 $ 2,498 As of December 31, 2019 U.S. Government agencies & GSEs $ 404 $ 1 $ — $ — $ 404 $ 1 Residential mortgage-backed, Agency & GSE 228,611 576 18,294 150 246,905 726 Commercial mortgage-backed, Agency & GSE — — 33,517 128 33,517 128 Commercial mortgage-backed, Non-agency — — 4,864 263 4,864 263 Corporate bonds 19,742 216 998 2 20,740 218 Asset-backed securities 32,294 625 38,990 1,047 71,284 1,672 Total unrealized loss position $ 281,051 $ 1,418 $ 96,663 $ 1,590 $ 377,714 $ 3,008 At December 31, 2020, there were 72 debt securities available-for-sale and 13 debt securities held-to-maturity that were in an unrealized loss position. Management does not intend to sell nor believes it will be required to sell securities in an unrealized loss position prior to the recovery of its amortized cost basis. Unrealized losses at December 31, 2020 and 2019 were primarily attributable to changes in interest rates. At adoption of ASC 326 on January 1, 2020 and at December 31, 2020, calculated credit losses and, thus, the related ACL on held-to-maturity debt securities were not material due to the high credit quality of the portfolio. As a result, no ACL was recorded on the held-to-maturity portfolio at December 31, 2020. In addition, based on the assessment performed as of December 31, 2020, there was no ACL required related to the available-for-sale portfolio. See Note 1 for additional details on the adoption of ASC 326 as it relates to the securities portfolio. Prior to the adoption of ASC 326, management evaluated securities for other-than-temporary impairment at least on a quarterly basis, and more frequently when economic or market concerns warranted such evaluation. Consideration was given to the length of time and the extent to which the fair value had been less than cost, the financial condition and near-term prospects of the issuer, among other factors. In analyzing an issuer’s financial condition, management considered whether the securities were issued by the federal government or its agencies, whether downgrades by bond rating agencies had occurred, and industry analyst’s reports. No impairment charges were recognized during 2019 or 2018. Realized gains and losses are derived using the specific identification method for determining the cost of the securities sold. The following summarizes securities sales activities for the years ended December 31 (in thousands) : 2020 2019 2018 Proceeds from sales $ 40,625 $ 352,106 $ 168,891 Gross gains on sales $ 748 $ 1,843 $ 2,082 Gross losses on sales — (2,864) (2,738) Net gains (losses) on sales of securities $ 748 $ (1,021) $ (656) Income tax expense (benefit) attributable to sales $ 191 $ (247) $ (132) The amortized cost and fair value of debt available-for-sale and held-to-maturity securities at December 31, 2020, by contractual maturity, are presented in the following table (in thousands). Expected maturities may differ from contractual maturities because issuers and borrowers may have the right to call or prepay obligations. Available-for-Sale Held-to-Maturity Amortized Cost Fair Value Amortized Cost Fair Value Within 1 year: U.S. Treasuries $ 20,014 $ 20,311 $ — $ — U.S. Government agencies & GSEs 201 201 — — State and political subdivisions 20,020 20,232 1,700 1,743 Corporate bonds 11,441 11,592 — — 51,676 52,336 1,700 1,743 1 to 5 years: U.S. Treasuries 103,663 107,761 — — U.S. Government agencies & GSEs 16,710 16,820 — — State and political subdivisions 48,354 51,544 14,505 16,059 Corporate bonds 44,636 45,837 — — 213,363 221,962 14,505 16,059 5 to 10 years: U.S. Government agencies & GSEs 55,588 55,481 — — State and political subdivisions 59,837 64,843 7,028 7,957 Corporate bonds 13,206 13,485 — — 128,631 133,809 7,028 7,957 More than 10 years: U.S. Government agencies & GSEs 80,097 80,470 10,575 10,590 State and political subdivisions 125,419 137,853 174,490 179,380 Corporate bonds 774 853 — — 206,290 219,176 185,065 189,970 Debt securities not due at a single maturity: Asset-backed securities 562,076 562,722 — — Residential mortgage-backed securities 1,449,873 1,485,585 113,400 118,173 Commercial mortgage-backed securities 540,202 549,131 98,663 103,291 Total $ 3,152,111 $ 3,224,721 $ 420,361 $ 437,193

Loans and Leases and Allowance

Loans and Leases and Allowance for Credit Losses	12 Months Ended
	Dec. 31, 2020
Receivables [Abstract]
Loans and Leases and Allowance for Credit Losses	Loans and Leases and Allowance for Credit Losses Major classifications of the loan and lease portfolio (collectively referred to as the “loan portfolio” or “loans”) are summarized as of the dates indicated as follows (in thousands) : December 31, 2020 2019 Owner occupied commercial real estate $ 2,090,443 $ 1,720,227 Income producing commercial real estate 2,540,750 2,007,950 Commercial & industrial (1) 2,498,560 1,220,657 Commercial construction 967,305 976,215 Equipment financing 863,830 744,544 Total commercial 8,960,888 6,669,593 Residential mortgage 1,284,920 1,117,616 Home equity lines of credit 697,117 660,675 Residential construction 281,430 236,437 Consumer 146,460 128,232 Total loans 11,370,815 8,812,553 Less ACL - loans (137,010) (62,089) Loans, net $ 11,233,805 $ 8,750,464 (1) Commercial and industrial loans as of December 31, 2020 included $646 million o f PPP loans. At December 31, 2020 and 2019, $2.18 million and $1.30 million, respectively, in overdrawn deposit accounts were reclassified as consumer loans. At December 31, 2020, the loan portfolio was subject to blanket pledges on certain qualifying loan types with the FHLB and FRB to secure contingent funding sources. The following table presents loans sold by United for the periods presented (in thousands). The gains and losses on these loan sales were included in noninterest income on the consolidated statements of income. Loans Sold 2020 2019 2018 Guaranteed portion of SBA/USDA loans $ 48,385 $ 81,158 $ 120,977 Equipment financing receivables 27,018 30,952 — Indirect auto loans — 102,789 — Total $ 75,403 $ 214,899 $ 120,977 At December 31, 2020 and 2019, equipment financing assets included leases of $36.8 million and $37.4 million, respectively. The components of the net investment in leases, which included both sales-type and direct financing, are presented below (in thousands) . December 31, 2020 2019 Minimum future lease payments receivable $ 38,934 $ 39,709 Estimated residual value of leased equipment 3,263 3,631 Initial direct costs 672 842 Security deposits (727) (989) Purchase accounting premium 117 273 Unearned income (5,457) (6,088) Net investment in leases $ 36,802 $ 37,378 Minimum future lease payments expected to be received from equipment financing lease contracts as of December 31, 2020 were as follows (in thousands) : Year 2021 $ 15,152 2022 11,516 2023 7,452 2024 3,429 2025 1,341 Thereafter 44 Total $ 38,934 Nonaccrual and Past Due Loans The following table presents the amortized cost basis in loans by aging category and accrual status as of December 31, 2020 (in thousands). Short-term deferrals of approximately $70.7 million related to the COVID-19 crisis are not reported as past due during the deferral period. Accruing Loans Past Due Current Loans 30 - 59 Days 60 - 89 Days > 90 Days Nonaccrual Loans Total Loans As of December 31, 2020 Owner occupied commercial real estate $ 2,079,845 $ 2,013 $ 3 $ — $ 8,582 $ 2,090,443 Income producing commercial real estate 2,522,743 1,608 1,250 — 15,149 2,540,750 Commercial & industrial 2,480,483 1,176 267 — 16,634 2,498,560 Commercial construction 964,947 231 382 — 1,745 967,305 Equipment financing 856,985 2,431 1,009 — 3,405 863,830 Total commercial 8,905,003 7,459 2,911 — 45,515 8,960,888 Residential mortgage 1,265,019 5,549 1,494 — 12,858 1,284,920 Home equity lines of credit 692,504 1,942 184 — 2,487 697,117 Residential construction 280,551 365 — — 514 281,430 Consumer 145,770 429 36 — 225 146,460 Total loans $ 11,288,847 $ 15,744 $ 4,625 $ — $ 61,599 $ 11,370,815 The following table presents the aging of recorded investment in loans, including accruing and nonaccrual loans, as of December 31, 2019 (in thousands). Loans Past Due - Accrual and Non-accrual As of December 31, 2019 30 - 59 Days 60 - 89 Days > 90 Days (1) Total Current Loans PCI Loans Total Owner occupied commercial real estate $ 2,913 $ 2,007 $ 6,079 $ 10,999 $ 1,700,682 $ 8,546 $ 1,720,227 Income producing commercial real estate 562 706 401 1,669 1,979,053 27,228 2,007,950 Commercial & industrial 2,140 491 2,119 4,750 1,215,581 326 1,220,657 Commercial construction 1,867 557 96 2,520 966,833 6,862 976,215 Equipment financing 2,065 923 3,045 6,033 734,526 3,985 744,544 Total commercial 9,547 4,684 11,740 25,971 6,596,675 46,947 6,669,593 Residential mortgage 5,655 2,212 2,171 10,038 1,097,999 9,579 1,117,616 Home equity lines of credit 1,697 421 1,385 3,503 655,762 1,410 660,675 Residential construction 325 125 402 852 235,211 374 236,437 Consumer 668 181 27 876 127,020 336 128,232 Total loans $ 17,892 $ 7,623 $ 15,725 $ 41,240 $ 8,712,667 $ 58,646 $ 8,812,553 ( 1) Excluding PCI loans, substantially all loans more than 90 days past due were on nonaccrual status at December 31, 2019. The following table presents nonaccrual loans by loan class for the periods indicated (in thousands) . Nonaccrual loans CECL Incurred Loss December 31, 2020 December 31, 2019 With no allowance With an allowance Total Owner occupied commercial real estate $ 6,614 $ 1,968 $ 8,582 $ 10,544 Income producing commercial real estate 10,008 5,141 15,149 1,996 Commercial & industrial 2,004 14,630 16,634 2,545 Commercial construction 1,339 406 1,745 2,277 Equipment financing 156 3,249 3,405 3,141 Total commercial 20,121 25,394 45,515 20,503 Residential mortgage 1,855 11,003 12,858 10,567 Home equity lines of credit 1,329 1,158 2,487 3,173 Residential construction 274 240 514 939 Consumer 181 44 225 159 Total $ 23,760 $ 37,839 $ 61,599 $ 35,341 The gross additional interest revenue that would have been earned if the loans classified as nonaccrual had performed in accordance with the original terms was approximately $2.86 million, $1.26 million, and $1.09 million for 2020, 2019, and 2018, respectively. Risk Ratings United categorizes commercial loans, with the exception of equipment financing receivables, into risk categories based on relevant information about the ability of borrowers to service their debt such as: current financial information, historical payment experience, credit documentation, public information, and current industry and economic trends, among other factors. United analyzes loans individually by classifying the loans as to credit risk. This analysis is performed on a continual basis. United uses the following definitions for its risk ratings: Pass. Loans in this category are considered to have a low probability of default and do not meet the criteria of the risk categories below. Watch . Loans in this category are presently protected from apparent loss, however weaknesses exist that could cause future impairment, including the deterioration of financial ratios, past due status and questionable management capabilities. These loans require more than the ordinary amount of supervision. Collateral values generally afford adequate coverage, but may not be immediately marketable. Substandard. These loans are inadequately protected by the current net worth and paying capacity of the obligor or by the collateral pledged. Specific and well-defined weaknesses exist that may include poor liquidity and deterioration of financial ratios. The loan may be past due and related deposit accounts experiencing overdrafts. There is the distinct possibility that United will sustain some loss if deficiencies are not corrected. If possible, immediate corrective action is taken. Doubtful. Specific weaknesses characterized as Substandard that are severe enough to make collection in full highly questionable and improbable. There is no reliable secondary source of full repayment. Loss. Loans categorized as Loss have the same characteristics as Doubtful; however probability of loss is certain. Loans classified as Loss are charged off. Equipment Financing Receivables and Consumer Purpose Loans . United applies a pass / fail grading system to all equipment financing receivables and consumer purpose loans. Under this system, loans that are on nonaccrual status, become past due 90 days or are in bankruptcy are classified as “fail” and all other loans are classified as “pass”. For reporting purposes, loans classified as “fail” are reported as “substandard” and all other loans are reported as “pass”. Based on the most recent analysis performed, the amortized cost of loans by risk category by vintage year as of December 31, 2020 is as follows (in thousands) : Term Loans by Origination Year Revolvers Revolvers converted to term loans Total December 31, 2020 2020 2019 2018 2017 2016 Prior Pass Owner occupied commercial real estate $ 707,501 $ 368,615 $ 231,316 $ 197,778 $ 201,362 $ 229,667 $ 56,273 $ 9,072 $ 2,001,584 Income producing commercial real estate 815,799 376,911 361,539 277,769 206,068 198,080 28,542 12,128 2,276,836 Commercial & industrial 1,092,767 287,857 263,439 115,790 92,968 58,359 515,593 3,777 2,430,550 Commercial construction 314,154 217,643 226,308 53,708 30,812 21,985 20,278 3,947 888,835 Equipment financing 413,653 270,664 125,869 39,982 9,404 445 — — 860,017 Total commercial 3,343,874 1,521,690 1,208,471 685,027 540,614 508,536 620,686 28,924 8,457,822 Residential mortgage 468,945 195,213 125,492 120,944 122,013 230,771 18 5,393 1,268,789 Home equity lines of credit — — — — — — 675,878 17,581 693,459 Residential construction 225,727 30,646 4,026 4,544 3,172 12,546 — 64 280,725 Consumer 54,997 25,528 14,206 4,531 3,595 1,677 41,445 76 146,055 4,093,543 1,773,077 1,352,195 815,046 669,394 753,530 1,338,027 52,038 10,846,850 Watch Owner occupied commercial real estate 8,759 4,088 4,221 10,025 11,138 4,728 100 — 43,059 Income producing commercial real estate 35,471 42,831 39,954 13,238 24,164 11,337 — 1,681 168,676 Commercial & industrial 1,451 16,315 2,176 630 459 17 6,464 — 27,512 Commercial construction 21,366 272 816 23,292 11,775 477 — — 57,998 Equipment financing — — — — — — — — — Total commercial 67,047 63,506 47,167 47,185 47,536 16,559 6,564 1,681 297,245 Residential mortgage — — — — — — — — — Home equity lines of credit — — — — — — — — — Residential construction — — — — — — — — — Consumer — — — — — — — — — 67,047 63,506 47,167 47,185 47,536 16,559 6,564 1,681 297,245 Substandard Owner occupied commercial real estate 6,586 10,473 7,596 3,717 6,753 8,473 1,528 674 45,800 Income producing commercial real estate 45,125 8,940 2,179 5,034 31,211 2,652 — 97 95,238 Commercial & industrial 1,545 5,536 6,193 1,684 1,292 1,485 22,170 593 40,498 Commercial construction 2,466 735 13,741 340 1,931 250 — 1,009 20,472 Equipment financing 631 1,392 1,371 306 96 17 — — 3,813 Total commercial 56,353 27,076 31,080 11,081 41,283 12,877 23,698 2,373 205,821 Residential mortgage 2,049 2,106 3,174 1,369 679 5,860 — 894 16,131 Home equity lines of credit — — — — — — 265 3,393 3,658 Residential construction 106 37 54 4 124 380 — — 705 Consumer — 97 49 60 78 98 — 23 405 58,508 29,316 34,357 12,514 42,164 19,215 23,963 6,683 226,720 Total $ 4,219,098 $ 1,865,899 $ 1,433,719 $ 874,745 $ 759,094 $ 789,304 $ 1,368,554 $ 60,402 $ 11,370,815 The following table presents the risk category of loans by class of loan as of December 31, 2019 (in thousands) : As of December 31, 2019 Pass Watch Substandard Doubtful / Total Owner occupied commercial real estate $ 1,638,398 $ 24,563 $ 48,720 $ — $ 1,711,681 Income producing commercial real estate 1,914,524 40,676 25,522 — 1,980,722 Commercial & industrial 1,156,366 16,385 47,580 — 1,220,331 Commercial construction 960,251 2,298 6,804 — 969,353 Equipment financing 737,418 — 3,141 — 740,559 Total commercial 6,406,957 83,922 131,767 — 6,622,646 Residential mortgage 1,093,902 — 14,135 — 1,108,037 Home equity lines of credit 654,619 — 4,646 — 659,265 Residential construction 234,791 — 1,272 — 236,063 Consumer 127,507 8 381 — 127,896 Total loans, excluding PCI loans 8,517,776 83,930 152,201 — 8,753,907 Owner occupied commercial real estate 3,238 2,797 2,511 — 8,546 Income producing commercial real estate 19,648 6,305 1,275 — 27,228 Commercial & industrial 104 81 141 — 326 Commercial construction 3,628 590 2,644 — 6,862 Equipment financing 3,952 — 33 — 3,985 Total commercial 30,570 9,773 6,604 — 46,947 Residential mortgage 8,112 — 1,467 — 9,579 Home equity lines of credit 1,350 — 60 — 1,410 Residential construction 348 — 26 — 374 Consumer 303 — 33 — 336 Total PCI loans 40,683 9,773 8,190 — 58,646 Total loan portfolio $ 8,558,459 $ 93,703 $ 160,391 $ — $ 8,812,553 At December 31, 2019, the carrying value and outstanding balance of PCI loans was $58.6 million and $83.1 million, respectively. The following table presents changes in the value of the accretable yield for PCI loans for the year ended December 31, 2019 (in thousands) : Balance at beginning of period $ 26,868 Additions due to acquisitions 1,300 Accretion (17,885) Reclassification from nonaccretable difference 9,237 Changes in expected cash flows that do not affect nonaccretable difference 4,400 Balance at end of period $ 23,920 Troubled Debt Restructurings and Other Modifications As of December 31, 2020 and 2019, United had TDRs totaling $61.6 million and $54.2 million, respectively. As of December 31, 2020, United had remaining short-term deferrals related to the COVID-19 crisis of approximately $70.7 million, which generally represented payment deferrals for up to 90 days. To the extent that these deferrals qualified under either the CARES Act or interagency guidance, they were not considered new TDRs. Loans modified under the terms of a TDR during the years ended December 31 are presented in the table below. In addition, the following table presents loans modified under the terms of a TDR that defaulted (became 90 days or more delinquent) during the years ended December 31 that were initially restructured within one year prior to default (dollars in thousands) : New TDRs Number of Post-Modification Outstanding Recorded Investment TDRs Modified Within the Year That Have Subsequently Defaulted Year Ended December 31, 2020 Rate Structure Other Total Number of Contracts Recorded Owner occupied commercial real estate 8 $ — $ 833 $ 1,536 $ 2,369 — $ — Income producing commercial real estate 7 — 4,856 6,699 11,555 1 5,998 Commercial & industrial 4 — 586 15 601 3 819 Commercial construction 7 — 832 70 902 — — Equipment financing 172 — 5,821 5,821 22 944 Total commercial 198 — 12,928 8,320 21,248 26 7,761 Residential mortgage 40 — 4,359 3 4,362 2 145 Home equity lines of credit 4 — 164 — 164 1 60 Residential construction 3 — 123 — 123 — — Consumer 7 — 11 24 35 1 3 Total loans 252 $ — $ 17,585 $ 8,347 $ 25,932 30 $ 7,969 Year Ended December 31, 2019 Owner occupied commercial real estate 4 $ — $ 1,739 $ — $ 1,739 — $ — Income producing commercial real estate 3 — 9,013 — 9,013 — — Commercial & industrial 2 — 75 7 82 — — Commercial construction — — — — — — — Equipment financing 9 — 1,071 — 1,071 — — Total commercial 18 — 11,898 7 11,905 — — Residential mortgage 15 — 2,057 — 2,057 1 135 Home equity lines of credit 1 — 50 — 50 — — Residential construction 1 — — 21 21 1 13 Consumer 5 — — 45 45 — — Indirect auto 15 — — 262 262 — — Total loans 55 $ — $ 14,005 $ 335 $ 14,340 2 $ 148 Year Ended December 31, 2018 Owner occupied commercial real estate 5 $ — $ 1,387 $ — $ 1,387 3 $ 1,869 Income producing commercial real estate 2 106 3,637 — 3,743 — — Commercial & industrial 2 — 32 — 32 1 232 Commercial construction — — — — — 1 3 Equipment financing — — — — — — — Total commercial 9 106 5,056 — 5,162 5 2,104 Residential mortgage 15 130 1,770 — 1,900 1 101 Home equity lines of credit 1 — — 41 41 — — Residential construction 2 — 32 13 45 — — Consumer 2 — — 7 7 — — Indirect auto 35 — — 643 643 — — Total loans 64 $ 236 $ 6,858 $ 704 $ 7,798 6 $ 2,205 Allowance for Credit Losses The following table presents the balance and activity in the ACL by portfolio segment for the periods indicated (in thousands) : CECL Year Ended December 31, 2020 Dec. 31, 2019 Adoption of CECL Jan. 1, 2020 Initial ACL- PCD loans (1) Charge-Offs Recoveries Provision Ending Owner occupied commercial $ 11,404 $ (1,616) $ 9,788 $ 1,779 $ (70) $ 2,565 $ 6,611 $ 20,673 Income producing commercial 12,306 (30) 12,276 1,208 (8,430) 3,546 33,137 41,737 Commercial & industrial 5,266 4,012 9,278 7,680 (10,707) 1,371 14,397 22,019 Commercial construction 9,668 (2,583) 7,085 74 (726) 1,045 3,474 10,952 Equipment financing 7,384 5,871 13,255 — (8,764) 2,004 10,325 16,820 Residential mortgage 8,081 1,569 9,650 195 (398) 455 5,439 15,341 Home equity lines of credit 4,575 1,919 6,494 209 (221) 677 1,258 8,417 Residential construction 2,504 (1,771) 733 — (93) 156 (32) 764 Consumer 901 (491) 410 7 (2,985) 2,259 596 287 ACL - loans 62,089 6,880 68,969 11,152 (32,394) 14,078 75,205 137,010 ACL - unfunded commitments 3,458 1,871 5,329 — — — 5,229 10,558 Total ACL $ 65,547 $ 8,751 $ 74,298 $ 11,152 $ (32,394) $ 14,078 $ 80,434 $ 147,568 (1) Represents the initial ACL related to PCD loans acquired in the Three Shores transaction. Incurred Loss Year Ended December 31, 2019 Beginning Charge-Offs Recoveries Provision Ending Owner occupied commercial real estate $ 12,207 $ (5) $ 375 $ (1,173) $ 11,404 Income producing commercial real estate 11,073 (1,227) 283 2,177 12,306 Commercial & industrial 4,802 (5,849) 852 5,461 5,266 Commercial construction 10,337 (290) 1,165 (1,544) 9,668 Equipment financing 5,452 (5,675) 781 6,826 7,384 Residential mortgage 8,295 (616) 481 (79) 8,081 Home equity lines of credit 4,752 (996) 610 209 4,575 Residential construction 2,433 (306) 157 220 2,504 Consumer 853 (2,390) 911 1,527 901 Indirect auto 999 (663) 186 (522) — ACL - loans 61,203 (18,017) 5,801 13,102 62,089 ACL - unfunded commitments 3,410 — — 48 3,458 Total ACL $ 64,613 $ (18,017) $ 5,801 $ 13,150 $ 65,547 Incurred Loss Year Ended December 31, 2018 Beginning Charge-Offs Recoveries Provision Ending Owner occupied commercial real estate $ 14,776 $ (303) $ 1,227 $ (3,493) $ 12,207 Income producing commercial real estate 9,381 (3,304) 1,064 3,932 11,073 Commercial & industrial 3,971 (1,669) 1,390 1,110 4,802 Commercial construction 10,523 (622) 734 (298) 10,337 Equipment financing — (1,536) 460 6,528 5,452 Residential mortgage 10,097 (754) 336 (1,384) 8,295 Home equity lines of credit 5,177 (1,194) 423 346 4,752 Residential construction 2,729 (54) 376 (618) 2,433 Consumer 710 (2,445) 807 1,781 853 Indirect auto 1,550 (1,277) 228 498 999 ACL - loans 58,914 (13,158) 7,045 8,402 61,203 ACL - unfunded commitments 2,312 — — 1,098 3,410 Total ACL $ 61,226 $ (13,158) $ 7,045 $ 9,500 $ 64,613 As of January 1, 2020 and December 31, 2020, United used a discounted cash flow methodology applied at a loan level with a one-year reasonable and supportable forecast period. Expected credit loss rates were estimated using a regression model based on historical data from peer banks which incorporates a third party vendor’s economic forecast to predict the change in credit losses. These results were then combined with a starting value that was based on United’s recent default experience, which was adjusted for select portfolios based on expectations of future performance. At December 31, 2020, the third party vendor’s forecast, which was representative of a baseline scenario, captured the recent challenging economic environment that included high levels of unemployment, but also indicated mild improvement in the short term. The increase in the ACL compared to January 1, 2020 was primarily attributable to the worsening trends in the forecast at December 31, 2020 compared to the beginning of 2020, with the primary economic forecast driver being the change in unemployment claims due to policy decisions made in response to the COVID-19 pandemic. At December 31, 2020, United adjusted the economic forecast by eliminating the initial spike in unemployment evidenced in the first half of the year to account for the impact of government stimulus programs. In addition, United used a model overlay for the economic forecast for residential mortgage loans to better align losses in that portfolio to current conditions. For periods beyond the reasonable and supportable forecast period of one year, United reverted to historical credit loss information on a straight line basis over two years. For all collateral types excluding residential mortgage, United reverted to through-the-cycle average default rates using peer data from 2000 to 2017. For loans secured by residential mortgages, the peer data was adjusted for changes in lending practices designed to prevent the magnitude of losses observed during the mortgage crisis. PPP loans were considered low risk assets due to the related 100% guarantee by the SBA and were therefore excluded from the calculation. Disaggregation of Incurred Loss Impairment Methodology The following table presents the recorded investment in loans by portfolio segment and the balance of the ACL assigned to each segment based on the method of evaluating the loans for impairment as of December 31, 2019 (in thousands) : Loans Outstanding Allowance for Credit Losses Individually Collectively PCI Ending Individually Collectively PCI Ending Owner occupied commercial real estate $ 19,233 $ 1,692,448 $ 8,546 $ 1,720,227 $ 816 $ 10,483 $ 105 $ 11,404 Income producing commercial real estate 18,134 1,962,588 27,228 2,007,950 770 11,507 29 12,306 Commercial & industrial 1,449 1,218,882 326 1,220,657 21 5,193 52 5,266 Commercial construction 3,675 965,678 6,862 976,215 55 9,613 — 9,668 Equipment financing 1,027 739,532 3,985 744,544 — 7,240 144 7,384 Residential mortgage 15,991 1,092,046 9,579 1,117,616 782 7,296 3 8,081 Home equity lines of credit 992 658,273 1,410 660,675 16 4,541 18 4,575 Residential construction 1,256 234,807 374 236,437 47 2,456 1 2,504 Consumer 214 127,682 336 128,232 5 885 11 901 Total ACL - loans $ 61,971 $ 8,691,936 $ 58,646 $ 8,812,553 2,512 59,214 363 62,089 ACL - unfunded commitments — 3,458 — 3,458 Total ACL $ 2,512 $ 62,672 $ 363 $ 65,547 The following table presents loans individually evaluated for impairment by class of loans as of the dates indicated (in thousands) : December 31, 2019 Unpaid Principal Balance Recorded Investment ACL Allocated With no related ACL recorded: Owner occupied commercial real estate $ 9,527 $ 8,118 $ — Income producing commercial real estate 5,159 4,956 — Commercial & industrial 1,144 890 — Commercial construction 2,458 2,140 — Equipment financing 1,027 1,027 — Total commercial 19,315 17,131 — Residential mortgage 7,362 6,436 — Home equity lines of credit 1,116 861 — Residential construction 731 626 — Consumer 66 53 — Total with no related ACL recorded 28,590 25,107 — With an ACL recorded: Owner occupied commercial real estate 11,136 11,115 816 Income producing commercial real estate 13,591 13,178 770 Commercial & industrial 559 559 21 Commercial construction 1,535 1,535 55 Equipment financing — — — Total commercial 26,821 26,387 1,662 Residential mortgage 9,624 9,555 782 Home equity lines of credit 146 131 16 Residential construction 643 630 47 Consumer 161 161 5 Total with an ACL recorded 37,395 36,864 2,512 Total $ 65,985 $ 61,971 $ 2,512 The average balances of impaired loans and income recognized on impaired loans while they were considered impaired is presented below for the periods indicated (in thousands) : 2019 2018 Average Interest Cash Basis Average Interest Cash Basis Owner occupied commercial $ 18,575 $ 1,124 $ 1,171 $ 19,881 $ 1,078 $ 1,119 Income producing commercial 14,253 739 730 17,138 893 895 Commercial & industrial 1,837 84 100 1,777 100 100 Commercial construction 3,233 129 146 3,247 176 174 Equipment financing 159 23 23 — — — Total commercial 38,057 2,099 2,170 42,043 2,247 2,288 Residential mortgage 16,115 748 749 14,515 641 643 Home equity lines of credit 488 14 15 284 18 16 Residential construction 1,332 92 94 1,405 96 95 Consumer 203 15 15 249 18 18 Indirect auto 1,028 50 50 1,252 64 64 Total $ 57,223 $ 3,018 $ 3,093 $ 59,748 $ 3,084 $ 3,124

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment Premises and equipment are summarized as follows as of the dates indicated (in thousands) : December 31, 2020 2019 Land and land improvements $ 82,816 $ 81,150 Buildings and improvements 173,497 170,629 Furniture and equipment 96,157 97,997 Construction in progress 7,590 1,701 360,060 351,477 Less accumulated depreciation (141,571) (135,501) Premises and equipment, net $ 218,489 $ 215,976 Depreciation expense was $15.6 million, $15.3 million and $14.2 million for 2020, 2019 and 2018, respectively.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities The table below presents the fair value of derivative financial instruments as of the dates indicated as well as their classification on the consolidated balance sheets (in thousands) : December 31, 2020 December 31, 2019 Notional Amount Fair Value Fair Value Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities Derivatives designated as hedging instruments: Cash flow hedge of subordinated debt $ 100,000 $ 3,378 $ — $ — $ — Cash flow hedge of trust preferred securities 20,000 — — — — Fair value hedge of brokered CDs 20,000 — — — 880 Total 140,000 3,378 — — 880 Derivatives not designated as hedging instruments: Customer derivative positions 1,329,271 72,508 17 27,277 446 Dealer offsets to customer derivative positions 1,329,271 1 24,614 394 6,425 Risk participations 48,843 28 12 — 12 Mortgage banking - loan commitment 253,243 10,751 — 1,970 — Mortgage banking - forward sales commitment 325,145 — 1,964 98 86 Bifurcated embedded derivatives 51,935 — 1,449 5,268 — Dealer offsets to bifurcated embedded derivatives 51,935 — 947 — 7,667 Total 3,389,643 83,288 29,003 35,007 14,636 Total derivatives $ 3,529,643 $ 86,666 $ 29,003 $ 35,007 $ 15,516 Total gross derivative instruments $ 86,666 $ 29,003 $ 35,007 $ 15,516 Less: Amounts subject to master netting agreements (114) (114) (401) (401) Less: Cash collateral received/pledged (3,200) (27,092) — (14,933) Net amount $ 83,352 $ 1,797 $ 34,606 $ 182 United clears certain derivatives centrally through the CME. CME rules legally characterize variation margin payments for centrally cleared derivatives as settlements of the derivatives’ exposure rather than as collateral. As a result, the variation margin payment and the related derivative instruments are considered a single unit of account for accounting purposes. Variation margin, as determined by the CME, is settled daily. As a result, derivative contracts that clear through the CME have an estimated fair value of zero. Hedging Derivatives Cash Flow Hedges of Interest Rate Risk United enters into cash flow hedges to mitigate exposure to the variability of future cash flows or other forecasted transactions. During the second quarter of 2020, United entered into three cash flow hedges using interest rate caps and swaps with an aggregate notional amount of $120 million to hedge the variability of cash flows due to changes in interest rates on certain of its variable-rate subordinated debt and trust preferred securities. United considers these derivatives to be highly effective at achieving offsetting changes in cash flows attributable to changes in interest rates. Therefore, changes in the fair value of these derivative instruments are recognized in other comprehensive income. Gains and losses related to changes in fair value are reclassified into earnings in the periods the hedged forecasted transactions occur. Losses representing amortization of the premium recorded on cash flow hedges, which is a component excluded from the assessment of effectiveness, are recognized in earnings on a straight-line basis in the same caption as the hedged item over the term of the hedge. Over the next twelve months United expects to reclassify $594,000 of losses from AOCI into earnings related to these agreements. At December 31, 2019, United had no active cash flow hedges. The loss remaining in other comprehensive income from prior hedges that had previously been de-designated was being amortized into earnings over the original term of the swaps as the forecasted transactions that the swaps were originally designated to hedge were still expected to occur. This was the only effect of cash flow hedges on the consolidated statements of income for the years ended December 31, 2019 and 2018. During the second quarter of 2019, United amortized the remaining balance of losses on terminated hedging positions from other comprehensive income. See Note 17 for further detail. Fair Value Hedges of Interest Rate Risk United is exposed to changes in the fair value of certain of its fixed-rate obligations due to changes in interest rates. United uses interest rate swaps to manage its exposure to changes in fair value on these instruments attributable to changes in interest rates. For derivatives designated and that qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting loss or gain on the hedged item attributable to the hedged risk are recognized in earnings. United includes the gain or loss on the hedged items in the same income statement line item as the offsetting loss or gain on the related derivatives. At December 31, 2020 and 2019, United had two and four interest rate swaps with an aggregate notional amount of $20.0 million and $37.9 million, respectively, that were designated as fair value hedges of fixed-rate brokered time deposits. The swaps involved the receipt of fixed-rate amounts from a counterparty in exchange for United making variable rate payments over the life of the agreements. In certain cases, the estate of deceased brokered certificate of deposit holders may put the certificate of deposit back to United at par upon the death of the holder. When these events occur (estate puts), a gain or loss is recognized for the difference between the fair value and the par amount of the deposits put back. The change in the fair value of brokered time deposits that are being hedged in fair value hedging relationships reported in the table below includes gains and losses from estate puts. The table below presents the effect of derivatives in hedging relationships on the consolidated statements of income (in thousands) . Year Ended December 31, 2020 2019 2018 Interest expense Interest expense Interest expense Interest revenue - taxable investment securities Other noninterest income Total income (expense) presented in the $ (56,237) $ (83,312) $ (61,330) $ 73,496 $ 24,142 Gains (losses) on fair value hedging relationships: Interest rate contracts: Amounts related to interest settlements 291 (327) (245) 17 — Recognized on derivatives 870 733 (220) — 356 Recognized on hedged items (880) (766) (145) — (447) Net income (expense) recognized on fair value hedges $ 281 $ (360) $ (610) $ 17 $ (91) Losses on cash flow hedging relationships (1) : Interest rate contracts: Realized losses reclassified from AOCI into net income (2) $ (359) $ — $ — $ — $ — Net expense recognized on cash flow hedges $ (359) $ — $ — $ — $ — (1) Excludes 2019 and 2018 amortization of losses related to de-designated cash flow hedges. See Note 17 for further detail. (2) Includes $329,000 of premium amortization expense excluded from the assessment of hedge effectiveness for the year ended December 31, 2020. The table below presents the carrying amount of hedged fixed-rate brokered time deposits and cumulative fair value hedging adjustments included in the carrying amount of the hedged liability for the periods presented (in thousands) . December 31, 2020 2019 Balance Sheet Location Carrying amount of Assets (Liabilities) Hedge Accounting Basis Adjustment Carrying amount of Assets (Liabilities) Hedge Accounting Basis Adjustment Deposits $ (20,216) $ (235) $ (35,880) $ 645 Derivatives Not Designated as Hedging Instruments Customer derivative positions include swaps, caps, and collars between United and certain commercial loan customers with offsetting positions to dealers under a back-to-back program. In addition, United occasionally enters into credit risk participation agreements with counterparty banks to accept or transfer a portion of the credit risk related to interest rate swaps. The agreements, which are typically executed in conjunction with a participation in a loan with the same customer, allow customers to execute an interest rate swap with one bank while allowing for the distribution of the credit risk among participating members. United also has three interest rate swap contracts that are not designated as hedging instruments but are economic hedges of market-linked brokered certificates of deposit. The market-linked brokered certificates of deposit contain embedded derivatives that are bifurcated from the host instruments and marked to market through earnings. The fair value marks on the market linked swaps and the bifurcated embedded derivatives tend to move in opposite directions with changes in 90-day LIBOR and therefore provide an economic hedge. In addition, United originates certain residential mortgage loans with the intention of selling these loans. Between the time United enters into an interest-rate lock commitment to originate a residential mortgage loan that is to be held for sale and the time the loan is funded and eventually sold, United is subject to the risk of variability in market prices. United also enters into forward sale agreements to mitigate risk and to protect the expected gain on the eventual loan sale. The commitments to originate residential mortgage loans and forward loan sales commitments are freestanding derivative instruments. Fair value adjustments on these derivative instruments are recorded within mortgage loan gains and related fees in the consolidated statements of income. The table below presents the gains and losses recognized in income on derivatives not designated as hedging instruments for the periods indicated (in thousands) . Income Statement Location Year Ended December 31, 2020 2019 2018 Customer derivatives and dealer offsets Other noninterest income $ 6,732 $ 2,878 $ 2,658 Bifurcated embedded derivatives and dealer offsets Other noninterest income (63) 212 307 Interest rate caps Other noninterest income — — 501 De-designated hedges Other noninterest income — (193) 31 Mortgage banking derivatives Mortgage loan revenue (7,873) (1,797) 904 Risk participations Other noninterest income (340) (3) 12 Total gains and losses $ (1,544) $ 1,097 $ 4,413 Credit-risk-related Contingent Features United manages its credit exposure on derivative transactions by entering into a bilateral credit support agreement with each non-customer counterparty. The credit support agreements require collateralization of exposures beyond specified minimum threshold amounts. The details of these agreements, including the minimum thresholds, vary by counterparty. United’s agreements with each of its derivative counterparties contain a provision where if either party defaults on any of its indebtedness, then it could also be declared in default on its derivative obligations. The agreements with derivative counterparties also include provisions that if not met, could result in United being declared in default. United has agreements with certain of its derivative counterparties that provide that if United fails to maintain its status as a well-capitalized institution or is subject to a prompt corrective action directive, the counterparty could terminate the derivative positions and United would be required to settle its obligations under the agreements. Derivatives that are centrally cleared do not have credit-risk-related features that require additional collateral if United’s credit rating were downgraded.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets The carrying amount of goodwill and other intangible assets is summarized below as of the dates indicated (in thousands) : December 31, 2020 2019 Core deposit intangible $ 36,162 $ 32,802 Less: accumulated amortization (22,148) (17,980) Net core deposit intangible 14,014 14,822 Goodwill 367,809 327,425 Total goodwill and other intangible assets, net $ 381,823 $ 342,247 The following is a summary of changes in the carrying amounts of goodwill for the years indicated (in thousands) : Goodwill (1) December 31, 2018 $ 307,112 Acquisition of FMBT 20,313 December 31, 2019 327,425 Acquisition of Three Shores 40,384 December 31, 2020 $ 367,809 (1) Goodwill balances presented are shown net of accumulated impairment losses of $306 million incurred prior to 2018. Gross goodwill for December 31, 2020, 2019, and 2018 totaled $673 million, $633 million and $613 million, respectively. The estimated aggregate amortization expense for future periods for core deposit intangibles is as follows (in thousands) : Year 2021 $ 3,622 2022 2,915 2023 2,321 2024 1,834 2025 1,414 Thereafter 1,908 Total $ 14,014

Servicing Assets and Liabilitie

Servicing Assets and Liabilities	12 Months Ended
	Dec. 31, 2020
Transfers and Servicing [Abstract]
Servicing Assets and Liabilities	Servicing Assets and Liabilities Servicing Rights for SBA/USDA Loans United accounts for servicing rights for SBA/USDA loans at fair value. The following table summarizes the changes in SBA/USDA servicing rights for the years indicated ( in thousands ). 2020 2019 2018 Servicing rights for SBA/USDA loans, beginning of period $ 6,794 $ 7,510 $ 7,740 Originated servicing rights capitalized upon sale of loans 1,114 1,835 2,573 Disposals (624) (1,258) (810) Measurement period adjustment to acquired servicing rights — — (354) Changes in fair value due to change in inputs or assumptions used in the valuation (822) (1,293) (1,639) Servicing rights for SBA/USDA loans, end of period $ 6,462 $ 6,794 $ 7,510 The portfolio of SBA/USDA loans serviced for others, which is not included in the accompanying balance sheets, was $402 million and $411 million, respectively, at December 31, 2020 and 2019. The amount of contractually specified servicing fees earned by United on these servicing rights during the years ended December 31, 2020, 2019 and 2018 was $3.77 million, $3.82 million and $3.44 million, respectively. A summary of the key characteristics, inputs, and economic assumptions used in the discounted cash flow method utilized to estimate the fair value of the servicing asset for SBA/USDA loans and the sensitivity of the fair values to immediate adverse changes in those assumptions are shown in the table below as of the dates indicated (dollars in thousands) : December 31, 2020 2019 Fair value of retained servicing assets $ 6,462 $ 6,794 Prepayment rate assumption: Weighted average 17.8 % 16.5 % Range 2.7% - 33.6% 10% adverse change $ (358) $ (352) 20% adverse change (680) (671) Discount rate: Weighted average 8.9 % 12.3 % Range 1.6% - 44.1% 100 bps adverse change $ (171) $ (184) 200 bps adverse change (333) (358) Life (in years): Weighted-average 3.5 3.9 Range 0.6 - 5.6 Gross margin: Weighted-average 1.9 % 1.9 % Range 0.0% - 3.2% The above sensitivities are hypothetical and changes in fair value based on variations in assumptions generally cannot be extrapolated because the relationship of the change in assumption to the change in fair value may not be linear. Also, in this table, the effect of a variation in a particular assumption is calculated without changing any other assumption. In reality, changes in one factor may result in changes in another, which might magnify or counteract the sensitivities. Residential Mortgage Servicing Rights United accounts for residential mortgage servicing rights at fair value. The following table summarizes the changes in residential mortgage servicing rights for the years indicated ( in thousands ). 2020 2019 2018 Residential mortgage servicing rights, beginning of period $ 13,565 $ 11,877 $ 8,262 Originated servicing rights capitalized upon sale of loans 11,911 5,783 4,587 Disposals (2,868) (1,098) (537) Changes in fair value due to change in inputs or assumptions used in the valuation (6,392) (2,997) (435) Residential mortgage servicing rights, end of period $ 16,216 $ 13,565 $ 11,877 The portfolio of residential mortgage loans serviced for others, which is not included in the consolidated balance sheets, was $2.31 billion and $1.60 billion, respectively, at December 31, 2020 and 2019. The amount of contractually specified servicing fees earned by United on these servicing rights during the years ended December 31, 2020, 2019 and 2018 was $4.82 million, $3.67 million and $2.37 million, respectively. A summary of the key characteristics, inputs, and economic assumptions used to estimate the fair value of the servicing asset for residential mortgage loans and the sensitivity of the fair values to immediate adverse changes in those assumptions are shown in the table below as of the dates indicated (in thousands) : December 31, 2020 2019 Fair value of retained servicing assets $ 16,216 $ 13,565 Prepayment rate assumption: Weighted average 17.7 % 14.1 % Range 8.7% - 19.5% 10% adverse change $ (999) $ (662) 20% adverse change (1,912) (1,270) Discount rate: Weighted average 10.0 % 10.0 % Range 10.0% - 11.0% 100 bps adverse change $ (518) $ (467) 200 bps adverse change (1,001) (900) The above sensitivities are hypothetical and changes in fair value based on variations in assumptions generally cannot be extrapolated because the relationship of the change in assumption to the change in fair value may not be linear. Also, in this table, the effect of a variation in a particular assumption is calculated without changing any other assumption. In reality, changes in one factor may result in changes in another, which might magnify or counteract the sensitivities. Servicing Liabilities for Equipment Financing Loans United accounts for servicing liabilities associated with sold equipment finance loans using the amortization method. The portfolio of equipment financing loans serviced for others, which is not included in the accompanying balance sheets, was $45.5 million and $42.4 million at December 31, 2020 and 2019, respectively. The servicing liabilities related to these loans totaled $357,000 and $363,000 at December 31, 2020 and 2019, respectively.

Time Deposits

Time Deposits	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Time Deposits	Time Deposits At December 31, 2020, the contractual maturities of time deposits, including brokered time deposits, are summarized as follows (in thousands) : 2021 $ 1,418,807 2022 211,523 2023 59,153 2024 25,513 2025 20,816 Thereafter 50,579 Total time deposits $ 1,786,391 At December 31, 2020 and 2019, time deposits, excluding brokered time deposits, that met or exceeded the FDIC insurance limit of $250,000 totaled $317 million and $367 million, respectively.

Long-term Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt Long-term debt consisted of the following (in thousands) : December 31, Issue Date Stated Maturity Date Earliest Call Date 2020 2019 Interest Rate Obligations of the Bank: 2026 subordinated debentures $ 15,000 $ — 2016 2026 2021 5.875% through August 2021, 3-month LIBOR plus 4.70% thereafter 15,000 — Obligations of the Holding Company: 2022 senior debentures 50,000 50,000 2015 2022 2020 5.000% through August 2020, 3-month LIBOR plus 3.814% thereafter 2027 senior debentures 35,000 35,000 2015 2027 2025 5.500% through August 2025, 3-month LIBOR plus 3.71% thereafter 2030 senior debentures 100,000 — 2020 2030 2025 5.00% through June 2025, 3-month SOFR plus 4.87% thereafter Total senior debentures 185,000 85,000 2028 subordinated debentures 100,000 100,000 2018 2028 2023 4.500% through January 2023, 3-month LIBOR plus 2.12% thereafter 2025 subordinated debentures 11,250 11,250 2015 2025 2020 6.250% Total subordinated debentures 111,250 111,250 Southern Bancorp Capital Trust I 4,382 4,382 2004 2034 2009 Prime + 1.00% Tidelands Statutory Trust I 8,248 8,248 2006 2036 2011 3-month LIBOR plus 1.38% Four Oaks Statutory Trust I 12,372 12,372 2006 2036 2011 3-month LIBOR plus 1.35% Total trust preferred securities 25,002 25,002 Less net discount (9,296) (8,588) Total long-term debt $ 326,956 $ 212,664 Interest is currently paid at least semiannually for all senior and subordinated debentures, and trust preferred securities.

Operating Leases

Operating Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Operating Leases	Operating Leases The following table presents the balances of the right-of-use asset and corresponding operating lease liability as of the dates indicated (in thousands). December 31, Balance Sheet Location 2020 2019 Right-of-use asset Other assets $ 31,398 $ 19,894 Operating lease liability Other liabilities 33,095 22,039 During 2020, United obtained building and office space right-of-use assets resulting in an increase in its operating lease liability of $17.4 million. Leases assumed as part of the Three Shores transaction accounted for $15.1 million of the increase. The table below presents the operating lease income and expense recognized for the periods indicated (in thousands). Income Statement Location 2020 2019 Operating lease cost Occupancy expense $ 6,449 $ 5,067 Variable lease cost Occupancy expense 757 449 Short-term lease cost Occupancy expense 100 136 Total lease cost $ 7,306 $ 5,652 Sublease income and rental income from owned properties under operating leases Other noninterest income $ 1,022 $ 1,160 Rent expense recorded in accordance with ASC 840 for the year ended December 31, 2018 was $4.70 million. As of December 31, 2020, the weighted average remaining lease term and weighted average discount rate of operating leases was 5.74 years and 1.79%, respectively. Absent a readily determinable interest rate in the lease agreement, the discount rate applied to each individual lease obligation was the Bank’s incremental borrowing rate for secured borrowings. As of December 31, 2020, future minimum lease payments under operating leases were as follows (in thousands) : Year 2021 $ 7,446 2022 7,544 2023 6,953 2024 3,417 2025 2,403 Thereafter 6,996 Total 34,759 Less discount (1,664) Present value of lease liability $ 33,095

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value MeasurementsFair value measurements are determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair value measurements, United uses a fair value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy). United has processes in place to review the significant valuation inputs and to reassess how the instruments are classified in the valuation framework. Fair Value Hierarchy Level 1 Valuation is based upon quoted prices (unadjusted) in active markets for identical assets or liabilities that United has the ability to access. Level 2 Valuation is based upon quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 Valuation is generated from model-based techniques that use at least one significant assumption based on unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. United’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability. The following is a description of the valuation methodologies used for assets and liabilities recorded at fair value. Investment Securities Debt securities available-for-sale and equity securities with readily determinable fair values are recorded at fair value on a recurring basis. Fair value measurement is based upon quoted prices, if available. If quoted prices are not available, fair values are measured using independent pricing models or other model-based valuation techniques such as the present value of future cash flows, adjusted for the security’s credit rating, prepayment assumptions and other factors such as credit loss assumptions. Level 1 securities include those traded on an active exchange, such as the New York Stock Exchange, U.S. Treasury securities that are traded by dealers or brokers in active over-the-counter markets and money market funds. Level 2 securities include mortgage-backed securities issued by government sponsored entities, municipal bonds, corporate debt securities and asset-backed securities and are valued based on observable inputs that include: quoted market prices for similar assets, quoted market prices that are not in an active market or other inputs that are observable in the market and can be corroborated by observable market data for substantially the full term of the securities. Securities classified as Level 3 include those traded in less liquid markets and are valued based on estimates obtained from broker-dealers that are not directly observable. Deferred Compensation Plan Assets and Liabilities Included in other assets in the consolidated balance sheets are assets related to employee deferred compensation plans. The assets associated with these plans are invested in mutual funds and classified as Level 1. Deferred compensation liabilities, also classified as Level 1, are carried at the fair value of the obligation to the employee, which mirrors the fair value of the invested assets and is included in other liabilities in the consolidated balance sheets. Mortgage Loans Held for Sale United has elected the fair value option for newly originated mortgage loans held for sale in order to reduce certain timing differences and better match changes in fair values of the loans with changes in the value of derivative instruments used to economically hedge them. The fair value of mortgage loans held for sale is determined using quoted prices for a similar asset, adjusted for specific attributes of that loan and are classified as Level 2. Derivative Financial Instruments United uses derivatives to manage interest rate risk. The valuation of these instruments is typically determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves and implied volatilities. The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts and the discounted expected variable cash payments. The variable cash payments are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. United also uses best effort and mandatory delivery forward loan sale commitments to hedge risk in its mortgage lending business. United incorporates credit valuation adjustments (“CVAs”) as necessary to appropriately reflect the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, United has considered the effect of netting and any applicable credit enhancements, such as collateral postings, thresholds and guarantees. Management has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy. However, the CVAs associated with these derivatives utilize Level 3 inputs, such as estimates of current credit spreads, to evaluate the likelihood of default by itself and its counterparties. Generally, management’s assessment of the significance of the CVAs has indicated that they are not a significant input to the overall valuation of the derivatives. In cases where management’s assessment indicates that the CVA is a significant input, the related derivative is disclosed as a Level 3 value. During the second quarter of 2020, certain derivative assets were transferred from Level 2 to Level 3 of the fair value hierarchy due to a change in the assessment of significance of the CVA. Other derivatives classified as Level 3 include structured derivatives for which broker quotes, used as a key valuation input, were not observable. Risk participation agreements are classified as Level 3 instruments due to the incorporation of significant Level 3 inputs used to evaluate the probability of funding and the likelihood of customer default. Interest rate lock commitments, which relate to mortgage loan commitments, are categorized as Level 3 instruments as the fair value of these instruments is based on unobservable inputs for commitments that United does not expect to fund. Servicing Rights for Residential Mortgage and SBA/USDA Loans United recognizes servicing rights upon the sale of residential mortgage and SBA/USDA loans sold with servicing retained. Management has elected to carry these assets at fair value. Given the nature of the assets, the key valuation inputs are unobservable and management considers these Level 3 assets. For disclosure regarding the fair value of servicing rights, see Note 10. Assets and Liabilities Measured at Fair Value on a Recurring Basis The table below presents United’s assets and liabilities measured at fair value on a recurring basis, aggregated by the level in the fair value hierarchy within which those measurements fall (in thousands) : December 31, 2020 Level 1 Level 2 Level 3 Total Assets: Debt securities available for sale: U.S. Treasuries $ 128,072 $ — $ — $ 128,072 U.S. Government agencies & GSEs — 152,972 — 152,972 State and political subdivisions — 274,472 — 274,472 Residential mortgage-backed securities — 1,485,585 — 1,485,585 Commercial mortgage-backed securities — 549,131 — 549,131 Corporate bonds — 70,017 1,750 71,767 Asset-backed securities — 562,722 — 562,722 Equity securities with readily determinable fair values 774 913 — 1,687 Mortgage loans held for sale — 105,433 — 105,433 Deferred compensation plan assets 9,584 — — 9,584 Servicing rights for SBA/USDA loans — — 6,462 6,462 Residential mortgage servicing rights — — 16,216 16,216 Derivative financial instruments — 75,887 10,779 86,666 Total assets $ 138,430 $ 3,277,132 $ 35,207 $ 3,450,769 Liabilities: Deferred compensation plan liability $ 9,590 $ — $ — $ 9,590 Derivative financial instruments — 26,595 2,408 29,003 Total liabilities $ 9,590 $ 26,595 $ 2,408 $ 38,593 December 31, 2019 Level 1 Level 2 Level 3 Total Assets: Securities available for sale: U.S. Treasuries $ 154,618 $ — $ — $ 154,618 U.S. Government agencies & GSEs — 3,035 — 3,035 State and political subdivisions — 226,490 — 226,490 Residential mortgage-backed securities — 1,299,025 — 1,299,025 Commercial mortgage-backed securities — 284,953 — 284,953 Corporate bonds — 202,093 998 203,091 Asset-backed securities — 103,369 — 103,369 Equity securities with readily determinable fair values 1,973 — — 1,973 Mortgage loans held for sale — 58,484 — 58,484 Deferred compensation plan assets 8,133 — — 8,133 Servicing rights for SBA/USDA loans — — 6,794 6,794 Residential mortgage servicing rights — — 13,565 13,565 Derivative financial instruments — 27,769 7,238 35,007 Total assets $ 164,724 $ 2,205,218 $ 28,595 $ 2,398,537 Liabilities: Deferred compensation plan liability $ 8,132 $ — $ — $ 8,132 Derivative financial instruments — 6,957 8,559 15,516 Total liabilities $ 8,132 $ 6,957 $ 8,559 $ 23,648 For disclosure regarding the fair value of servicing rights, see Note 10. The following table shows a reconciliation of the beginning and ending balances for all other assets measured at fair value on a recurring basis using significant unobservable inputs that are classified as Level 3 values (in thousands) : Derivative Derivative Debt Securities December 31, 2017 $ 12,207 $ 16,744 $ 900 Sales and settlements (1,029) (1,347) — Other comprehensive income — — 95 Amounts included in earnings - fair value adjustments 663 335 — December 31, 2018 11,841 15,732 995 Sales and settlements (1,135) (2,330) — Other comprehensive income — — 3 Amounts included in earnings - fair value adjustments (3,468) (4,843) — December 31, 2019 7,238 8,559 998 Transfers into Level 3 583 — — Additions 368 — 1,750 Sales and settlements — — (1,000) Other comprehensive income — — 2 Amounts included in earnings - fair value adjustments 2,590 (6,151) — December 31, 2020 $ 10,779 $ 2,408 $ 1,750 The following table presents quantitative information about recurring Level 3 fair value measurements, excluding servicing rights which are detailed in Note 10 (in thousands) : Valuation Technique December 31, Level 3 Assets Unobservable Inputs 2020 2019 Low High Weighted Average Weighted Average Corporate bonds Indicative bid provided by a broker Multiple factors, including but not limited to, current operations, financial condition, cash flows, and similar financing transactions executed in the market N/A N/A N/A N/A Derivative assets - mortgage Internal model Pull through rate 65.6% 100% 83.9% 83.6% Derivative assets - customer derivative positions Internal model Probability of default rate & loss given default 100 100 100 N/A Derivative assets & liabilities - risk participations Internal model Probable exposure rate 0.06 3.66 1.81 0.36 Probability of default rate 0.16 13.1 4.03 1.80 Derivative assets & liabilities - other Dealer priced Dealer priced N/A N/A N/A N/A Fair Value Option United records mortgage loans held for sale at fair value under the fair value option. Interest income on these loans is calculated based on the note rate of the loan and is recorded in interest revenue. The following tables present the fair value and outstanding principal balance of these loans, as well as the gain or loss recognized resulting from the change in fair value for the periods indicated (in thousands) . Mortgage Loans Held for Sale December 31, 2020 2019 Outstanding principal balance $ 99,746 $ 56,613 Fair value 105,433 58,484 Amount of Gain (Loss) Recognized on Location 2020 2019 2018 Mortgage loan gains and other related fees $ 3,815 $ 1,177 $ (133) Changes in fair value were mostly offset by hedging activities. An immaterial portion of these amounts was attributable to changes in instrument-specific credit risk. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis United may be required, from time to time, to measure certain assets at fair value on a nonrecurring basis. These adjustments to fair value usually result from the application of lower of amortized cost or fair value accounting or write-downs of individual assets due to impairment. The following table presents the fair value hierarchy and carrying value of all assets that were still held as of December 31, 2020 and 2019, for which a nonrecurring fair value adjustment was recorded during the periods presented (in thousands) . December 31, 2020 Level 1 Level 2 Level 3 Total Loans $ — $ — $ 29,404 $ 29,404 December 31, 2019 Loans $ — $ — $ 20,977 $ 20,977 Loans that are reported above as being measured at fair value on a nonrecurring basis are generally impaired loans that have either been partially charged off or have been assigned a specific reserve. Nonaccrual loans that are collateral dependent are generally written down to net realizable value, which reflects fair values less the estimated costs to sell. Specific reserves that are established based on appraised value of collateral are considered nonrecurring fair value adjustments as well. When the fair value of the collateral is based on an observable market price or a current appraised value, United records the impaired loan as nonrecurring Level 2. When an appraised value is not available or management determines the fair value is further impaired below the appraised value and there is no observable market price, United records the impaired loan as nonrecurring Level 3. Assets and Liabilities Not Measured at Fair Value For financial instruments that have quoted market prices, those quotes are used to determine fair value. Financial instruments that have no defined maturity, have a remaining maturity of 180 days or less, or reprice frequently to a market rate are assumed to have a fair value that approximates reported book value, after taking into consideration any applicable credit risk. If no market quotes are available, financial instruments are valued by discounting the expected cash flows using an estimated current market interest rate for the financial instrument. For off-balance sheet derivative instruments, fair value is estimated as the amount that United would receive or pay to terminate the contracts at the reporting date, taking into account the current unrealized gains or losses on open contracts. Cash and cash equivalents and repurchase agreements have short maturities and therefore the carrying value approximates fair value. Due to the short-term settlement of accrued interest receivable and payable, the carrying amount closely approximates fair value. Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect the premium or discount on any particular financial instrument that could result from the sale of United’s entire holdings. All estimates are inherently subjective in nature. Changes in assumptions could significantly affect the estimates. Fair value estimates are based on existing on and off-balance sheet financial instruments without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. Significant assets and liabilities that are not considered financial instruments include the mortgage banking operation, wealth management network, deferred income taxes, premises and equipment and goodwill. In addition, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimates. Off-balance sheet instruments (commitments to extend credit and standby letters of credit) for which draws can be reasonably predicted are generally short-term and at variable rates. Therefore, both the carrying amount and the estimated fair value associated with these instruments are immaterial. The carrying amount and fair values for other financial instruments that are not measured at fair value on a recurring basis in United’s consolidated balance sheets are as follows (in thousands) : Carrying Amount Fair Value Level December 31, 2020 Level 1 Level 2 Level 3 Total Assets: Securities held to maturity $ 420,361 $ — $ 437,193 $ — $ 437,193 Loans, net 11,233,805 — — 11,209,717 11,209,717 Liabilities: Deposits 15,232,358 — 15,232,274 — 15,232,274 Long-term debt 326,956 — — 336,763 336,763 December 31, 2019 Assets: Securities held to maturity $ 283,533 $ — $ 287,904 $ — $ 287,904 Loans, net 8,750,464 — — 8,714,592 8,714,592 Liabilities: Deposits 10,897,244 — 10,897,465 — 10,897,465 Long-term debt 212,664 — — 217,665 217,665

Common and Preferred Stock

Common and Preferred Stock	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Common and Preferred Stock	Common and Preferred Stock Common Stock In November of 2020, United’s Board re-authorized its common stock repurchase plan to permit the repurchase of up to $50 million of its common stock. The program is scheduled to expire on the earlier of United’s repurchase of its common stock having an aggregate purchase price of $50 million or December 31, 2021. Under the program, shares may be repurchased in open market transactions or in privately negotiated transactions, from time to time, subject to market conditions. During 2020 and 2019, 826,482 and 500,495 shares were repurchased under the program, respectively. During 2018, no shares were repurchased under the program. As of December 31, 2020, United had remaining authorization to repurchase up to $50.0 million of outstanding common stock under the program. United sponsors a DRIP that allows participants who already own United’s common stock to purchase additional shares directly from the Company. The DRIP also allows participants to automatically reinvest their quarterly dividends in additional shares of common stock without a commission. In 2020, 2019 and 2018, 38,107, 62,629 and 7,307 shares, respectively, were issued under the DRIP. Preferred Stock During 2020, United issued $100 million, or 4,000 shares, of Series I perpetual non-cumulative preferred stock (“Preferred Stock”) with a dividend rate of 6.875% per annum for net proceeds of $96.4 million and corresponding depositary shares each representing a 1/1,000th interest in one share of Preferred Stock. If declared, dividends are payable quarterly in arrears. The Preferred Stock has no stated maturity and redemption is solely at the option of United in whole, but not in part, upon the occurrence of a regulatory capital treatment event, as defined. In addition, the Preferred Stock may be redeemed on or after September 15, 2025 at a cash redemption price equal to $25,000 per share (equivalent to $25 per depositary share) plus any declared and unpaid dividends. As of December 31, 2020, the Preferred Stock had a carrying amount of $96.4 million. United had no preferred stock outstanding as of December 31, 2019.

Equity Compensation Plans

Equity Compensation Plans	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Equity Compensation Plans	Equity Compensation PlansUnited has an equity compensation plan that allows for grants of various share-based compensation. Options granted under the plan can have an exercise price no less than the fair market value of the underlying stock at the date of grant. The general terms of the plan include a vesting period (usually four years) with an exercisable period not to exceed ten years. Certain options and restricted stock unit awards provide for accelerated vesting if there is a change in control of United or certain other conditions are met (as defined in the plan document). As of December 31, 2020, 908,000 additional awards could be granted under the plan. Restricted stock units and options outstanding and activity for the years ended December 31 consisted of the following: Restricted Stock Units Options Shares Weighted Average Grant Date Fair Value Aggregate Shares Weighted Average Exercise Price December 31, 2017 663,817 $ 22.40 60,287 $ 24.12 Granted 416,484 30.54 — — Vested / Exercised (290,013) 20.18 (12,000) 11.85 Cancelled (30,542) 23.65 (1,148) 31.50 December 31, 2018 759,746 27.66 47,139 27.07 Granted 315,827 26.74 — — Vested / Exercised (216,138) 25.38 (13,000) 16.34 Expired — (30,243) 31.43 Cancelled (51,011) 27.18 (2,396) 29.68 December 31, 2019 808,424 27.94 1,500 27.95 Granted 446,512 19.15 — — Vested / Exercised (324,697) 26.42 $ 7,212 — — Expired — (1,500) 27.95 Cancelled (36,808) 25.73 — — December 31, 2020 893,431 23.75 25,409 — No compensation expense relating to options was included in earnings for 2020 or 2019. Compensation expense relating to options of $18,000 was included in earnings for 2018. The amount of compensation expense for all periods was determined based on the fair value of options at the time of grant, multiplied by the number of options granted that were expected to vest, which was then amortized over the vesting period. Compensation expense for restricted stock units without market conditions is based on the market value of United’s common stock on the date of grant. United recognizes the impact of forfeitures as they occur. The value of restricted stock unit awards is amortized into expense over the service period. Compensation expense recognized in the consolidated statements of income for employee restricted stock unit awards in 2020, 2019 and 2018 was $7.40 million, $8.98 million and $5.69 million, respectively. Of the expense related to restricted stock unit awards during the twelve months ended December 31, 2019, $1.38 million related to the modification of existing awards resulting from an acceleration of vesting of awards due to retirement and $740,000 related to awards granted in conjunction with an acquisition, both of which were recognized in merger-related and other charges in the consolidated statement of income. The remaining 2019 expense of $6.86 million was recognized in salaries and employee benefits expense, as were the entire amounts for 2020 and 2018. In addition, in 2020, 2019, and 2018, $484,000, $379,000 and $338,000, respectively, was recognized in other operating expenses for restricted stock unit awards granted to members of the Board. During 2020, 2019 and 2018, in addition to time-based restricted stock unit awards, the Board approved PSUs. The PSUs will vest based on achieving, during the applicable calendar-year performance periods, certain performance and market targets relative to a bank peer group. Achievement of the base-level performance and market targets for all applicable periods will result in the issuance of 148,109 shares, which are included in the outstanding balance in the table above. Additional shares may be issued if more stringent performance and market hurdles are met. The grant date per share fair market value of these PSUs was estimated using the Monte Carlo Simulation valuation model. Deferred income tax benefits related to compensation expense for options and restricted stock units of $2.01 million, $2.39 million and $1.54 million were included in the determination of income tax expense in 2020, 2019 and 2018, respectively. As of December 31, 2020, there was $14.4 million of unrecognized compensation cost related to restricted stock units granted under the plan. The cost is expected to be recognized over a weighted-average period of 2.6 years.

Reclassifications Out of AOCI

Reclassifications Out of AOCI	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Reclassifications Out of AOCI	Reclassifications Out of AOCI The following presents the details regarding amounts reclassified out of AOCI (in thousands). Amounts Reclassified from AOCI For the Years Ended December 31, Details about AOCI Components Affected Line Item in the Statement Where Net Income is Presented 2020 2019 2018 Realized gains (losses) on available-for-sale securities: $ 748 $ (1,021) $ (656) Securities gains (losses), net (191) 247 132 Income tax (expense) benefit $ 557 $ (774) $ (524) Net of tax Amortization of losses included in net income on available-for-sale securities transferred to held to maturity: $ (723) $ (383) $ (739) Investment securities interest revenue 173 92 180 Income tax benefit $ (550) $ (291) $ (559) Net of tax Reclassifications related to derivative financial instruments accounted for as cash flow hedges: Amortization of losses on de-designated positions $ — $ (235) $ — Other expense Amortization of losses on de-designated positions — (102) (499) Deposit interest expense Interest rate contracts (359) — — Long-term debt interest expense (359) (337) (499) Total before tax 91 86 129 Income tax benefit $ (268) $ (251) $ (370) Net of tax Reclassifications related to defined benefit pension plan activity: Prior service cost $ (531) $ (640) $ (666) Salaries and employee benefits expense Actuarial losses (326) (59) (241) Other expense Termination of Funded Plan — (1,558) — Merger-related and other (857) (2,257) (907) Total before tax 219 576 247 Income tax benefit $ (638) $ (1,681) $ (660) Net of tax Total reclassifications for the period $ (899) $ (2,997) $ (2,113) Net of tax Amounts shown above in parentheses reduce earnings

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the computation of basic and diluted net income per common share for the years indicated (in thousands, except per share data) : Year Ended December 31, 2020 2019 2018 Net income $ 164,089 $ 185,721 $ 166,111 Undistributed earnings allocated to participating securities (1,287) (1,375) (1,184) Dividends on preferred stock (3,533) — — Net income available to common stockholders $ 159,269 $ 184,346 $ 164,927 Net income per common share: Basic $ 1.91 $ 2.31 $ 2.07 Diluted 1.91 2.31 2.07 Weighted average common shares: Basic 83,184 79,700 79,662 Effect of dilutive securities: Stock options — 1 7 Restricted stock units 64 7 2 Diluted 83,248 79,708 79,671 At December 31, 2020, United had no potentially dilutive instruments outstanding that were not included in the above analysis. At December 31, 2019, United had the following potentially dilutive instruments outstanding: 1,000 shares of common stock issuable upon exercise of stock options with a weighted average exercise price of $30.45 and 183,168 shares of common stock issuable upon vesting of restricted stock unit awards. At December 31, 2018, United excluded 32,316 potentially dilutive shares of common stock issuable upon exercise of stock options because of their antidilutive effect.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense is as follows for the years indicated (in thousands) : Year Ended December 31, 2020 2019 2018 Current $ 42,688 $ 38,082 $ 17,185 Deferred 2,668 14,909 32,630 Total income tax expense $ 45,356 $ 52,991 $ 49,815 The differences between the provision for income taxes and the amount computed by applying the statutory federal income tax rate of 21% in 2020, 2019 and 2018 to income before income taxes are as follows for the years indicated (in thousands) : Year Ended December 31, 2020 2019 2018 Pretax income at statutory rates $ 43,983 $ 50,130 $ 45,344 Add (deduct): State taxes, net of federal benefit 5,928 7,168 6,765 BOLI earnings (1,052) (1,127) (747) Adjustment to reserve for uncertain tax positions (1,212) 84 80 Tax-exempt interest revenue (2,169) (1,827) (1,229) Equity compensation (174) (375) (892) Transaction costs 217 16 78 Tax credit investments (930) (464) (29) Change in state statutory tax rate — — 583 Other 765 (614) (138) Total income tax expense $ 45,356 $ 52,991 $ 49,815 The following summarizes the sources and expected tax consequences of future taxable deductions (revenue) which comprise the net DTA as of the dates indicated (in thousands) : December 31, 2020 2019 DTAs: ACL $ 33,213 $ 14,910 Net operating loss carryforwards 22,277 27,568 Deferred compensation 10,012 9,363 Loan purchase accounting adjustments 8,567 6,599 Reserve for losses on foreclosed properties 33 20 Nonqualified share based compensation 1,833 2,041 Accrued expenses 6,865 3,958 Investment in partnerships 71 67 Unamortized pension actuarial losses and prior service cost 1,981 1,739 Securities purchase accounting adjustments — 687 Lease liability 8,055 5,327 Other 4,018 1,351 Total DTAs 96,925 73,630 DTLs: Unrealized gains on securities available-for-sale 17,439 7,943 Unrealized gains on cash flow hedges 54 — Acquired intangible assets 2,576 2,530 Premises and equipment 4,241 3,002 Loan origination costs 4,857 3,538 True tax leases 7,846 7,783 Prepaid expenses 230 373 Servicing assets 4,816 4,428 Derivatives 2,250 1,075 Right-of-use asset 7,642 4,809 Securities purchase accounting adjustments 3,146 — Uncertain tax positions 1,813 1,792 Total DTLs 56,910 37,273 Less valuation allowance 1,604 2,298 Net DTA $ 38,411 $ 34,059 The change in the net DTA includes an increase of $16.3 million due to current year merger and acquisition activity and the adoption of CECL. At December 31, 2020, United had: • $36.0 million of state net operating loss carryforwards subject to annual limitation under IRC Section 382 that begin to expire in 2021, if not previously utilized. • $113 million of state net operating loss carryforwards that begin to expire in 2031, if not previously utilized. • $63.8 million in federal net operating loss carryforwards subject to annual limitation under IRC Section 382 that begin to expire in 2027, if not previously utilized. • $3.70 million of state tax credits that begin to expire in 2021, if not previously utilized. Management assesses the valuation allowance recorded against DTAs at each reporting period. The determination of whether a valuation allowance for DTAs is appropriate is subject to considerable judgment and requires an evaluation of all the positive and negative evidence. ASC 740 requires that companies assess whether a valuation allowance should be established against their DTAs based on the consideration of all available evidence using a “more likely than not” standard. At December 31, 2020 and 2019, based on the assessment of all the positive and negative evidence, management concluded that it is more likely than not that nearly all of the net DTA will be realized based upon future taxable income. The valuation allowance of $1.60 million and $2.30 million, respectively, was related to specific state income tax credits that have short carryforward periods and certain acquired state net operating losses, both of which are expected to expire unused. The valuation allowance could fluctuate in future periods based on the assessment of the positive and negative evidence. Management’s conclusion at December 31, 2020 that it was more likely than not that the net DTA of $38.4 million will be realized is based on management’s estimate of future taxable income. Management’s estimate of future taxable income is based on internal forecasts which consider historical performance, various internal estimates and assumptions, as well as certain external data all of which management believes to be reasonable although inherently subject to significant judgment. If actual results differ significantly from the current estimates of future taxable income, even if caused by adverse macro-economic conditions, the valuation allowance may need to be increased for some or all of the deferred tax asset. A reconciliation of the beginning and ending unrecognized tax benefit related to uncertain tax positions is as follows for the years indicated (in thousands) : 2020 2019 2018 Balance at beginning of year $ 3,370 $ 3,264 $ 3,163 Additions based on tax positions related to the current year 421 481 470 Decreases resulting from a lapse in the applicable statute of limitations (1,628) (375) (369) Balance at end of year $ 2,163 $ 3,370 $ 3,264 Approximately $1.71 million of the unrecognized tax benefit at December 31, 2020 would increase income from continuing operations, and thus affect United’s effective tax rate, if ultimately recognized into income. It is United’s policy to recognize interest and penalties accrued relative to unrecognized tax benefits in their respective federal or state income taxes accounts. There were no penalties and interest related to income taxes recorded in the income statement in 2020, 2019 or 2018. No amounts were accrued for interest and penalties on the balance sheet at December 31, 2020 or 2019. United and its subsidiaries file a consolidated U.S. federal income tax return, as well as various state returns in the states where it operates. United’s federal and state income tax returns are no longer subject to examination by taxing authorities for years before 2017.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans Defined Contribution Benefit Plans 401(k) Plan United offers a defined contribution 401(k) plan (the “401(k) Plan”) that covers substantially all employees meeting certain minimum service requirements. The 401(k) Plan allows employees to make pre-tax contributions to the 401(k) Plan and, United matches 100% of employee contributions up to 5% of eligible compensation. Employees begin to receive matching contributions after completing one year of service. Effective January 1, 2020, United amended the 401(k) Plan to be a safe harbor plan. Under safe harbor provisions, United is required to provide a matching contribution and participants are immediately 100% vested in safe harbor matching contributions. Under the safe harbor amendment the Company will continue to match 100% of participant deferral contributions up to 5% of the participant’s annual base salary and commissions for those who have completed at least one year of service. Prior to January 1, 2020, matching contributions vested after three years of service. United’s 401(k) Plan is administered in accordance with applicable laws and regulations. Compensation expense from continuing operations related to the 401(k) Plan totaled $6.16 million, $5.30 million and $4.73 million in 2020, 2019 and 2018, respectively. Deferred Compensation Plan United also sponsors a non-qualified deferred compensation plan for its executive officers, certain other key employees and members of the Board and its community banks’ advisory boards of directors. The deferred compensation plan provides for the pre-tax deferral of compensation, fees and other specified benefits. Specifically, the deferred compensation plan permits each employee participant to elect to defer a portion of his or her base salary, bonus or vested restricted stock units and permits each eligible director participant to elect to defer all or a portion of his or her director’s fees. Further, the deferred compensation plan allows for additional contributions by an employee, with matching contributions by United, for amounts that exceed the allowable amounts under the 401(k) Plan. During 2020, 2019 and 2018, United recognized $49,000, $162,000 and $119,000, respectively, in matching contributions for this provision of the deferred compensation plan. The Board may also elect to make a discretionary contribution to any or all participants. No discretionary contributions were made in 2020, 2019 or 2018. In addition to common stock related to elected deferrals of vested restricted stock units, United offers its common stock as an investment option for cash contributions to the deferred compensation plan. The common stock component is accounted for as an equity instrument and is reflected in the consolidated balance sheets as common stock issuable. The deferred compensation plan does not allow for diversification once an election is made to invest in United stock and settlement must be accomplished in shares at the time the deferral period is completed. At December 31, 2020 and 2019, United had 600,834 shares and 664,640 shares, respectively, of its common stock that was issuable under the deferred compensation plan. Defined Benefit Pension Plans United has an unfunded noncontributory defined benefit pension plan, or the Modified Retirement Plan, that covers certain executive officers and other key employees. The Modified Retirement Plan provides a fixed annual retirement benefit to plan participants. Weighted-average assumptions used to determine the pension benefit obligation of the Modified Retirement Plan at year end and net periodic pension cost are shown in the table below: 2020 2019 Discount rate for disclosures 2.55 % 3.25 % Discount rate for net periodic benefit cost 3.25 % 4.40 % Measurement date 12/31/2020 12/31/2019 The Modified Retirement Plan discount rates are determined in consultation with the third-party actuary and are set by matching the projected benefit cash flow to a notional yield curve developed by reference to high-quality fixed income investments. The discount rates are determined as the rate which would provide the same present value as the plan cash flows discounted to the measurement date using the full series of spot rates along the notional yield curve as of the measurement date. United acquired Palmetto on September 1, 2015, including its funded noncontributory defined benefit pension plan, or the Funded Plan, which covered all full-time Palmetto employees who had fulfilled at least 12 months of continuous service and attained age 21 by December 31, 2007. Benefits under the Funded Plan were no longer accrued for service subsequent to 2007. During 2019, United settled the liabilities of its Funded Plan. Participants elected to receive either lump sum distributions or annuity contracts purchased from a third-party insurance company that provided for the payment of vested benefits. United contributed $4.90 million to the Funded Plan in the third quarter 2019 to fund its liquidation. As a result of the pension termination, unrecognized losses of $1.56 million, which were previously recorded in AOCI on the consolidated balance sheets, were recognized as expense and an additional pension plan settlement loss of $1.38 million was recorded in the consolidated statements of income. Including both charges, the total Funded Plan settlement loss was $2.94 million, which was included in merger-related and other charges for the year ended December 31, 2019. United recognizes the underfunded status of the plans as a liability in the consolidated balance sheets. Information about changes in obligations and plan assets follows (in thousands) : 2020 2019 Modified Modified Funded Accumulated benefit obligation: Accumulated benefit obligation - beginning of year $ 25,105 $ 21,736 $ 16,011 Service cost 588 392 — Interest cost 795 931 166 Plan amendments — 386 — Actuarial losses 1,804 2,390 1,489 Benefits paid (1,193) (730) (17,666) Accumulated benefit obligation - end of year 27,099 25,105 — Change in plan assets, at fair value: Beginning plan assets — — 12,595 Actual return — — 173 Employer contribution 1,193 730 4,898 Benefits paid (1,193) (730) (17,666) Plan assets - end of year — — — Funded status - end of year (plan assets less benefit obligations) $ (27,099) $ (25,105) $ — Components of net periodic benefit cost and other amounts recognized in other comprehensive income are as follows (in thousands): 2020 2019 2018 Modified Modified Funded Modified Funded Service cost $ 588 $ 392 $ — $ 363 $ — Interest cost 795 931 166 801 647 Expected return on plan assets — — (106) — (551) Amortization of prior service cost 531 635 — 666 — Amortization of net actuarial losses 326 59 — 241 — Net periodic benefit cost $ 2,240 $ 2,017 $ 60 $ 2,071 $ 96 The estimated net actuarial loss and prior service costs for the Modified Retirement Plan that will be amortized from AOCI into net periodic benefit cost over the next fiscal year are $575,000 and $469,000, respectively, as of December 31, 2020. The following table summarizes the estimated future benefit payments expected to be paid from the Modified Retirement Plan for the periods indicated (in thousands) . 2021 $ 1,170 2022 1,165 2023 1,159 2024 1,152 2025 1,195 2026-2030 7,675 Other United sponsored benefit plans United has an Employee Stock Purchase Program (“ESPP”) that allows eligible employees to purchase shares of common stock at a discount (10%), with no commission charges. During 2020, 2019 and 2018 United issued 34,423, 20,928 shares and 17,941 shares, respectively, through the ESPP.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2020
Regulatory Capital Requirements Under Banking Regulations [Abstract]
Regulatory Matters	Regulatory Matters Capital Requirements United and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary action by regulators that, if undertaken, could have a direct material effect on United. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, United and the Bank must meet specific capital guidelines that involve quantitative measures of the Bank’s assets, liabilities, and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors. Quantitative measures (as defined) established by regulation to ensure capital adequacy require United and the Bank to maintain minimum amounts and ratios of total capital, Tier 1 capital, and CET1 to RWAs, and of Tier 1 capital to average assets. United and the Bank are also subject to a “capital conservation buffer,” which is designed to absorb losses during periods of economic stress. Banking organizations with a ratio of CET1 to RWAs above the minimum but below the conservation buffer (or below the combined capital conservation buffer and countercyclical capital buffer, when the latter is applied) will face constraints on dividends, equity repurchases and discretionary bonus compensation based on the amount of the shortfall. As of December 31, 2020, United and the Bank were categorized as well-capitalized under the regulatory framework for prompt corrective action in effect at such time. To be categorized as well-capitalized at December 31, 2020, United and the Bank must have exceeded the well-capitalized guideline ratios in effect at such time, as set forth in the table below and have met certain other requirements. Management believes that United and the Bank exceeded all well-capitalized requirements at December 31, 2020, and there have been no conditions or events since year-end that would change the status of well-capitalized. Pursuant to the CARES Act, United has adopted relief provided by federal banking regulatory agencies for the delay of the adverse capital impact of CECL at adoption of ASC 326 and during the subsequent two-year period after adoption. This optional two-year delay is followed by an optional three-year transition period to phase out the aggregate amount of capital benefit provided during the initial two-year delay. Under the transition provision, the amount of aggregate capital benefit is phased out by 25% each year with the full impact of adoption completely recognized by the beginning of the sixth year after adoption. Regulatory capital ratios at December 31, 2020 and 2019, along with the minimum amounts required for capital adequacy purposes and to be well-capitalized under prompt corrective action provisions in effect at such times are presented below for United and the Bank (dollars in thousands) : Basel III Guidelines United Community Banks, Inc. United Community Bank Minimum (1) Well 2020 2019 2020 2019 Risk-based ratios: CET1 capital 4.5 % 6.5 % 12.31 % 12.97 % 13.31 % 14.87 % Tier 1 capital 6.0 8.0 13.10 13.21 13.31 14.87 Total capital 8.0 10.0 15.15 15.01 14.28 15.54 Tier 1 leverage ratio 4.0 5.0 9.28 10.34 9.42 11.63 CET1 capital $ 1,506,750 $ 1,275,148 $ 1,625,292 $ 1,458,720 Tier 1 capital 1,603,172 1,299,398 1,625,292 1,458,720 Total capital 1,854,368 1,476,302 1,743,045 1,524,267 RWAs 12,240,440 9,834,051 12,207,940 9,810,477 Average total assets 17,276,853 12,568,563 17,246,878 12,545,254 (1) As of December 31, 2020 and 2019, the additional capital conservation buffer in effect was 2.50%. Cash, Dividend, Loan and Other Restrictions At December 31, 2020 and 2019, the Bank did not have a required reserve balance at the Federal Reserve Bank of Atlanta. Federal and state banking regulations place certain restrictions on dividends paid by the Bank to the Holding Company. During 2020, the Bank received regulatory approval to pay cash dividends to the Holding Company of $150 million. No cash dividends were paid by the Bank to the Holding Company in 2019. The Federal Reserve Act requires that extensions of credit by the Bank to certain affiliates, including the Holding Company, be secured by specific collateral, that the extension of credit to any one affiliate be limited to 10% of capital and surplus (as defined), and that extensions of credit to all such affiliates be limited to 20% of capital and surplus. The Bank is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of their customers. These financial instruments include commitments to extend credit and letters of credit. These instruments involve, to varying degrees, elements of credit risk in excess of the amount recognized in the consolidated balance sheets. The contract amounts of these instruments reflect the extent of involvement the Bank has in particular classes of financial instruments. The exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and letters of credit written is represented by the contractual amount of these instruments. United uses the same credit policies in making commitments and conditional obligations as it uses for underwriting on-balance sheet instruments. In most cases, collateral or other security is required to support financial instruments with credit risk.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The following table summarizes, as of the dates indicated, the contract amount of off-balance sheet instruments (in thousands) : December 31, 2020 2019 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit $ 3,052,657 $ 2,126,275 Letters of credit 31,748 22,533 Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments may expire without being drawn on, the total commitment amounts do not necessarily represent future cash requirements. United evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary, upon extension of credit is based on management’s credit evaluation. Collateral held varies, but may include unimproved and improved real estate, certificates of deposit, personal property or other acceptable collateral. Letters of credit are conditional commitments issued by United and could result in the commitment being drawn on when the underlying transaction is consummated between the customer and the third party or upon the non-performance of the customer. Those guarantees are primarily issued to local businesses and government agencies. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. In most cases, the Bank holds real estate, certificates of deposit, and other acceptable collateral as security supporting those commitments for which collateral is deemed necessary. The extent of collateral held for those commitments varies. United maintains an ACL for unfunded loan commitments which is included in the balance of other liabilities in the consolidated balance sheets. The ACL for unfunded loan commitments is determined as part of the quarterly ACL analysis. See Note 1 for further detail. The Bank holds minor investments in certain limited partnerships for CRA purposes. As of December 31, 2020, the Bank had a recorded investment of $58.3 million in these limited partnerships, which is included in other assets on the consolidated balance sheet, and had committed to fund an additional $9.81 million related to future capital calls that has not been reflected in the consolidated balance sheet. United, in the normal course of business, is subject to various pending and threatened lawsuits in which claims for monetary damages are asserted. Although it is not possible to predict the outcome of these lawsuits, or the range of any possible loss, management, after consultation with legal counsel, does not anticipate that the ultimate aggregate liability, if any, arising from these lawsuits will have a material adverse effect on financial position or results of operations.

Condensed Financial Statements

Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only)	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only)	Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only) Balance Sheets As of December 31, 2020 and 2019 (in thousands) 2020 2019 Assets Cash and cash equivalents $ 289,243 $ 32,495 Investment in bank 2,028,965 1,814,414 Investment in other subsidiaries 752 752 Other assets 34,661 29,308 Total assets $ 2,353,621 $ 1,876,969 Liabilities and Shareholders’ Equity Long-term debt $ 311,956 $ 212,664 Other liabilities 34,135 28,613 Total liabilities 346,091 241,277 Shareholders’ equity 2,007,530 1,635,692 Total liabilities and shareholders’ equity $ 2,353,621 $ 1,876,969 Statements of Income For the Years Ended December 31, 2020, 2019 and 2018 (in thousands) 2020 2019 2018 Dividends from bank $ 150,000 $ — $ 161,500 Dividends from other subsidiaries — 4,651 850 Shared service fees from subsidiaries 13,020 14,721 10,257 Other 1,436 1,468 133 Total income 164,456 20,840 172,740 Interest expense 13,994 11,573 11,868 Other expense 16,473 18,965 14,456 Total expenses 30,467 30,538 26,324 Income tax benefit 2,681 8,711 1,640 Income (loss) before equity in undistributed earnings of subsidiaries 136,670 (987) 148,056 Equity in undistributed earnings of subsidiaries 27,419 186,708 18,055 Net income $ 164,089 $ 185,721 $ 166,111 Statements of Cash Flows For the Years Ended December 31, 2020, 2019 and 2018 (in thousands) 2020 2019 2018 Operating activities: Net income $ 164,089 $ 185,721 $ 166,111 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of the subsidiaries (27,419) (186,708) (18,055) Stock-based compensation 7,887 9,360 6,057 Change in assets and liabilities: Other assets (3,662) (3,022) 1,777 Other liabilities 5,261 2,080 3,124 Net cash provided by operating activities 146,156 7,431 159,014 Investing activities: Net cash received (paid) for acquisition 3,397 (52,093) (84,499) Purchases of premises and equipment — — (364) Purchases of debt securities available-for-sale and equity securities (2,750) (3,000) (2,489) Proceeds from sales and maturities of debt securities available-for-sale and equity securities — 83 — Net cash provided by (used in) investing activities 647 (55,010) (87,352) Financing activities: Repayment of long-term debt — (250) (7,424) Proceeds from issuance of long-term debt, net of issuance costs 98,552 — 98,188 Proceeds from issuance of preferred stock, net of issuance costs 96,422 — — Cash related to shares withheld to cover payroll taxes upon vesting of restricted stock units (3,119) (1,686) (1,998) Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans 1,317 2,193 679 Proceeds from exercise of stock options — 212 142 Repurchase of common stock (20,782) (13,020) — Cash dividends on preferred stock (3,533) — — Cash dividends on common stock (58,912) (53,044) (41,634) Net cash provided by (used in) financing activities 109,945 (65,595) 47,953 Net change in cash 256,748 (113,174) 119,615 Cash at beginning of year 32,495 145,669 26,054 Cash at end of year $ 289,243 $ 32,495 $ 145,669

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn February 18, 2021, the Board approved a regular quarterly cash dividend of $0.19 per common share and a preferred stock dividend of $429.6875 per preferred share (equivalent to $0.4296875 per depositary share, or 1/1000 interest per share). The common stock dividend is payable April 5, 2021, to common shareholders of record on March 15, 2021. The preferred stock dividend is payable March 15, 2021, to preferred shareholders of record on February 28, 2021.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of accounting	The accounting principles followed by United and the methods of applying these principles conform with GAAP and with general practices within the banking industry. The following is a description of the significant policies.
Organization and Basis of Presentation	Organization and Basis of Presentation The Holding Company is a bank holding company subject to the regulation of the Board of Governors of the Federal Reserve whose principal business is conducted by its wholly-owned commercial bank subsidiary, United Community Bank (the “Bank”). United is subject to regulation under the BHC Act. The consolidated financial statements include the accounts of the Holding Company, the Bank and other wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The Bank is a Georgia state chartered commercial bank that serves both rural and metropolitan markets in Georgia, South Carolina, North Carolina, Tennessee and Florida and provides a full range of banking services. The Bank is insured and subject to the regulation of the FDIC and is also subject to the regulation of the GADBF.
Use of Estimates	Use of Estimates In preparing the consolidated financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the dates of the balance sheet and revenue and expenses for the years then ended. Actual results could differ significantly from those estimates. Material estimates that are particularly susceptible to significant change are the determination of the ACL, the valuation of acquired loans, the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans, the valuation of goodwill and separately identifiable intangible assets associated with mergers and acquisitions, and the valuation of deferred tax assets.
Operating Segments	Operating Segments Operating segments are components of a business about which separate financial information is available and evaluated regularly by the chief operating decision maker in deciding how to allocate resources and assessing performance. Public companies are required to report certain financial information about operating segments in interim and annual financial statements. United’s community banking operations are divided among geographic regions and local community banks within those regions. Those regions and banks have similar economic characteristics and are therefore considered to be one operating segment. Additionally, management assessed other operating units to determine if they should be classified and reported as segments, including Mortgage, Wealth Management and Commercial Banking Solutions. Qualitatively, these business units are primarily operating in the same geographic footprint as the community banks and face many of the same customers as the community banks. While the chief operating decision maker does have some limited production information for these entities, that information is not complete since it does not include a full allocation of revenue, costs and capital from key corporate functions. The business units are currently viewed more as a product line extension of the community banks. However, management will continue to evaluate these business units for separate reporting as facts and circumstances change. Based on this analysis, United concluded that it has one operating and reportable segment.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include amounts due from banks, interest-bearing deposits in banks, federal funds sold, commercial paper, reverse repurchase agreements and short-term investments and are carried at cost. Federal funds are generally sold for one-day periods, interest-bearing deposits in banks are available on demand and commercial paper investments and reverse repurchase agreements mature within a period of less than 90 days. A portion of the cash on hand and on deposit with the Federal Reserve Bank of Atlanta was required to meet regulatory reserve requirements.
Investment Securities	Investment Securities Debt Securities: Debt securities are classified as held-to-maturity and carried at amortized cost when management has the positive intent and ability to hold them to maturity. Debt securities are classified as available-for-sale when they may be sold before maturity. Securities available-for-sale are carried at fair value, with unrealized holding gains and losses reported in other comprehensive income, net of tax. Interest income includes amortization of purchase premiums or discounts. Premiums and discounts on securities are generally amortized or accreted on the level-yield method without anticipating prepayments, except for mortgage-backed securities where prepayments are anticipated. Premiums on callable debt securities are amortized to their earliest call date. Gains and losses on sales are recorded on the trade date and determined using the specific identification method. Transfers of securities between categories are recorded at fair value at the date of transfer. Unrealized holding gains or losses associated with transfers of securities from available-for-sale to held-to-maturity are included in the balance of AOCI in the consolidated balance sheets. These unrealized holding gains or losses are amortized/accreted into income over the remaining life of the security as an adjustment to the yield in a manner consistent with the amortization or accretion of the original purchase premium or discount on the associated security. A debt security is placed on nonaccrual status at the time any principal or interest payments become 90 days delinquent. Interest accrued but not received for a security placed on nonaccrual is reversed against interest income. Equity securities: Equity securities are included in other assets on the consolidated balance sheets. Those with readily determinable fair values are carried at fair value with changes in fair value recognized in net income. Those without readily determinable fair values include, among others, FHLB stock held to meet FHLB requirements related to outstanding advances and CRA equity investments, including those where the returns are primarily derived from LIHTC. Our investment in FHLB stock, which totaled $13.3 million at December 31, 2020, is accounted for using the cost method of accounting. Our LIHTC investments are accounted for using the proportional amortization method of accounting for qualified affordable housing investments which
ACL - Held-to-Maturity Securities, Available-For-Sale Securities, and Off-Balance Sheet Credit Exposures	ACL - Held-to-Maturity Securities: Since the adoption of ASC 326, management measures current expected credit losses on held-to-maturity debt securities on a collective basis by major security type. Accrued interest receivable on held-to-maturity debt securities totaled $1.78 million at December 31, 2020 and was excluded from the estimate of credit losses. The estimate of current expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management classifies the held-to-maturity portfolio into the following major security types: U.S. Government agencies and GSEs, state and political subdivisions, residential mortgage-backed, agency and GSEs and commercial mortgage-backed, agency and GSEs. All of the residential and commercial mortgage-backed securities held by United as held-to-maturity are issued by U.S. Government agencies and GSEs. These securities are either explicitly or implicitly guaranteed by the U.S. government, are highly rated by major rating agencies and have a long history of no credit losses. The state and political subdivision securities are highly rated by major rating agencies. ACL - Available-For-Sale Securities: For available-for-sale debt securities in an unrealized loss position, United first assesses whether it intends to sell, or whether it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security's amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, United evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. Since the adoption of ASC 326, if the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an ACL is recorded for the credit loss, limited by the amount that the fair value is less than the amortized cost basis. Any amount of unrealized loss that has not been recorded through an ACL is recognized in other comprehensive income. Changes in the ACL are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the ACL when management believes the uncollectability of an available-for-sale security is confirmed or when either of the criteria regarding intent or requirement to sell is met. Accrued interest receivable on available-for-sale debt securities totaled $9.11 million at December 31, 2020 and was excluded from the estimate of credit losses.
Loans Held for Sale	Loans Held for SaleUnited has elected the fair value option for mortgage loans held for sale in order to reduce certain timing differences and match changes in fair values of the loans with changes in the fair value of derivative instruments used to economically hedge them.
Loans and Leases	Loans and Leases Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at amortized cost. Amortized cost is the principal balance outstanding, net of purchase premiums and discounts and deferred fees and costs. Accrued interest receivable related to loans totaled $35.5 million at December 31, 2020 and was reported in accrued interest receivable on the consolidated balance sheets. Interest income is accrued on the unpaid principal balance. Loan origination fees, net of certain direct origination costs, are deferred and recognized in interest income using methods that approximate a level yield without anticipating prepayments. Equipment Financing Lease Receivables: Equipment financing lease receivables, which are classified as sales-type or direct financing leases, are recorded as the sum of the future minimum lease payments, initial deferred costs and, if applicable, estimated or contractual residual values less unearned income and security deposits. For lease receivables with a residual value, the determination of such value is derived from a variety of sources including equipment valuation services, appraisals, and publicly available market data on recent sales transactions on similar equipment. The length of time until contract termination, the cyclical nature of equipment values and the limited marketplace for re-sale of certain leased assets are important variables considered in making this determination. Interest income, which is included in loan interest revenue in the consolidated statements of income, is recognized as earned using the effective interest method. Direct fees and costs associated with the origination of leases are deferred and included as a component of equipment financing receivables. Net deferred fees or costs are recognized as an adjustment to interest income over the contractual life of the lease using the effective interest method. These lease agreements may include options to renew and for the lessee to purchase the leased equipment at the end of the lease term. United excludes sales taxes from consideration in these lease contracts. PCD Loans (CECL): In acquisitions, United may acquire loans, some of which have experienced more than insignificant credit deterioration since origination. In those cases, United will consider internal loan grades, delinquency status and other relevant factors in assessing whether purchased loans are PCD. PCD loans are recorded at their fair value at the acquisition date. An initial ACL is determined using the same methodology as other loans held for investment and recognized as an adjustment to the acquisition price of the asset; thus, the sum of the loan's purchase price and ACL becomes its initial amortized cost basis. The difference between the initial amortized cost basis and the par value of the loan is a noncredit discount or premium, which is amortized into interest income over the life of the loan. Subsequent to initial recognition, PCD loans are subject to the same interest income recognition and impairment model as non-PCD loans, with changes to the ACL recorded through provision expense. Upon adoption of ASC 326, loans that were designated as PCI loans under the Incurred Loss guidance were classified as PCD loans without reassessment. PCI Loans (Incurred Loss): Prior to the adoption of ASC 326 on January 1, 2020, purchased loans with evidence of credit deterioration since origination were accounted for pursuant to ASC Topic 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality . These PCI loans were recorded at their estimated fair value at date of purchase. After acquisition, further losses evidenced by decreases in expected cash flows were recognized by an increase in the ACL. PCI loans were aggregated into pools of loans based on common risk characteristics such as the type of loan, payment status, or collateral type. United estimated the amount and timing of expected cash flows for each purchased loan pool and the expected cash flows in excess of the amount paid were recorded as interest income over the remaining life of the pool (accretable yield). The excess of the pool’s contractual principal and interest over expected cash flows was not recorded (nonaccretable difference). Over the life of the loan pool, expected cash flows continued to be estimated. If the present value of expected cash flows was less than the carrying amount, a loss was recorded. If the present value of expected cash flows was greater than the carrying amount, it was recognized as part of future interest revenue. Nonaccrual Loans: The accrual of interest is generally discontinued when a loan becomes 90 days past due or when management believes, after considering economic and business conditions and collection efforts, that the principal or interest will not be collectable in the normal course of business. A loan may continue to accrue interest after 90 days if it is well collateralized and in the process of collection. Past due status is based on contractual terms of the loan. During 2020, United granted loan payment deferrals in accordance with the CARES Act and interagency guidance for certain borrowers experiencing temporary cash flow shortages as a result of the COVID-19 pandemic. During the temporary payment deferral period, these loans are not considered past due. All interest accrued but not received for loans placed on nonaccrual is reversed against interest income. Interest received on such loans is accounted for using the cost-recovery method, until qualifying for return to accrual. Under the cost-recovery method, interest income is not recognized until the loan balance is reduced to zero. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current, there is a sustained period of repayment performance and future payments are reasonably assured. TDRs: A loan for which the terms have been modified resulting in a more than insignificant concession, and for which the borrower is experiencing financial difficulties, is generally considered to be a TDR. Modified terms that result in a TDR include one or a combination of the following: a reduction of the stated interest rate of the loan, an extension of the amortization period that would not otherwise be considered in the current market for new debt with similar risk characteristics; a restructuring of the borrower’s debt into an “A/B note structure” in which the A note would fall within the borrower’s ability to pay and the remainder would be included in the B note; a mandated bankruptcy restructuring; or interest-only payment terms greater than 90 days where the borrower is unable to amortize the loan. Collateral dependent TDRs that subsequently default or are placed on nonaccrual are charged down to the fair value of the collateral consistent with United’s policy for nonaccrual loans. As discussed in Note 2, in accordance with the CARES Act, United implemented loan modification programs in response to the COVID-19 pandemic in order to provide borrowers with flexibility with respect to repayment terms. These loan modifications were not considered TDRs to the extent that the borrower was impacted by the COVID-19 pandemic and was not more than 30 days past due at December 31, 2019, or in certain circumstances, at the time that the COVID-19 loan modification program was implemented, unless the loan was previously classified as a TDR. Impaired Loans (Incurred Loss): With the exception of PCI loans, a loan is considered impaired when, based on current events and circumstances, it is probable that all amounts due, according to the contractual terms of the loan, will not be collected. Individually impaired loans are measured based on the present value of expected future cash flows, discounted at the loan’s effective interest rate, at the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent. Interest revenue on impaired loans is discontinued when the loans meet the criteria for nonaccrual status. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not considered impaired. Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and borrower, including the length of the delay, the reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest owed. PCI loans are considered to be impaired when it is probable that United will be unable to collect all the cash flows expected at acquisition, plus additional cash flows expected to be collected arising from changes in estimates after acquisition. Loans that are accounted for in pools are evaluated collectively for impairment on a pool by pool basis based on expected pool cash flows. Discounts continue to be accreted as long as there are expected future cash flows in excess of the current carrying amount of the specifically-reviewed loan or pool. Prior to the implementation of CECL, management individually evaluated certain impaired loans on a quarterly basis, including all non-PCI nonaccrual relationships with a balance of $500,000 or greater and all TDRs for impairment. Impairment for
Concentration of Credit Risk	Concentration of Credit Risk: Most of United’s business activity is with customers located within the markets where it has banking operations. Therefore, United’s exposure to credit risk is significantly affected by changes in the economy within its markets. Approximately 69% of United’s loan portfolio is secured by real estate and is therefore susceptible to changes in real estate valuations.
ACL - Loans	ACL- Loans United implemented CECL upon adoption of ASC 326 on January 1, 2020. The following discussion provides a description of the methodology applied to calculate the ACL under CECL for 2020 and under the Incurred Loss method for periods prior to 2020. CECL: The ACL is a valuation account that is deducted from the loans' amortized cost basis to present the net amount expected to be collected on the loans. Loans are charged off against the ACL when management believes the uncollectability of a loan balance is confirmed. Accrued interest receivable is excluded from the estimate of credit losses. Management determines the ACL balance using relevant available information, from internal and external sources, relating to past events, current conditions, and reasonable and supportable forecasts. Historical credit behaviors along with model judgments provide the basis for the estimation of expected credit losses. Adjustments to modeled loss estimates may be made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, delinquency level, or term as well as for changes in environmental conditions, such as changes in economic conditions, property values, or other relevant factors. The ACL-loans is measured on a collective basis when similar risk characteristics exist. United has identified the following portfolio segments and calculates the ACL for each using a discounted cash flow methodology at the loan level, with loss rates, prepayment assumptions and curtailment assumptions driven by each loan’s collateral type: Owner occupied commercial real estate - Loans in this category are susceptible to business failure and general economic conditions. Income producing commercial real estate - Common risks for this loan category are declines in general economic conditions, declines in real estate value, declines in occupancy rates, and lack of suitable alternative use for the property. Commercial & industrial - Risks to this loan category include the inability to monitor the condition of the collateral, which often consists of inventory, accounts receivable and other non-real estate assets. Equipment and inventory obsolescence can also pose a risk. Declines in general economic conditions and other events can cause cash flows to fall to levels insufficient to service debt. Commercial construction - Risks common to commercial construction loans are cost overruns, changes in market demand for property, inadequate long-term financing arrangements and declines in real estate values. Equipment financing - Risks associated with equipment financing are similar to those described for commercial and industrial loans, including general economic conditions, as well as appropriate lien priority on equipment, equipment obsolescence and the general mobility of the collateral. Residential mortgage - Residential mortgage loans are susceptible to weakening general economic conditions, increases in unemployment rates and declining real estate values. Home equity lines of credit - Risks common to home equity lines of credit are general economic conditions, including an increase in unemployment rates, and declining real estate values that reduce or eliminate the borrower’s home equity. Residential construction - Residential construction loans are susceptible to the same risks as residential mortgage loans. Changes in market demand for property lead to longer marketing times resulting in higher carrying costs and declining values. Consumer - Risks common to consumer direct loans include unemployment and changes in local economic conditions as well as the inability to monitor collateral consisting of personal property. Indirect auto - Risks common to indirect auto loans include unemployment and changes in local economic conditions as well as the inability to monitor collateral. During 2019, United sold its portfolio of indirect auto loans. When management determines that foreclosure is probable or when the borrower is experiencing financial difficulty at the reporting date and repayment is expected to be provided substantially through the operation or sale of the collateral, expected credit losses are based on the fair value of the collateral at the reporting date, adjusted for selling costs as appropriate. When the discounted cash flow method is used to determine the ACL, management adjusts the effective interest rate used to discount expected cash flows to incorporate expected prepayments. The ACL on a TDR is measured using the same method as all other loans held for investment, except that the original interest rate is used to discount the expected cash flows, not the rate specified within the restructuring. Determining the Contractual Term: Expected credit losses are estimated over the contractual term of the loans, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals, and modifications unless either of the following applies: management has a reasonable expectation at the reporting date that a TDR will be executed with an individual borrower or the extension or renewal options are included in the original or modified contract at the reporting date and are not unconditionally cancellable by United. Incurred Loss ACL: Under the Incurred Loss method, the ACL represents an amount, which, in management’s judgment, is adequate to absorb probable losses on existing loans as of the date of the balance sheet. The Incurred Loss ACL is composed of general reserves, specific reserves, and PCI reserves. General reserves are determined by applying loss percentages to the individual loan categories that are based on actual historical loss experience. Additionally, the general economic and business conditions affecting key lending areas, credit quality trends, collateral values, loan volumes and concentrations, seasoning of the loan portfolio, the findings of internal and external credit reviews and results from external bank regulatory examinations are considered in this evaluation. The need for specific reserves was evaluated on nonaccrual loan relationships greater than $500,000 and all TDRs. The specific reserves were determined on a loan-by-loan basis based on management’s evaluation of United’s exposure for each credit, given the current payment status of the loan and the value of any underlying collateral. Loans for which specific reserves are provided are excluded from the calculation of general reserves. For PCI loans, a valuation allowance is established when it is probable that the Company will be unable to collect all the cash flows expected at acquisition plus additional cash flows expected to be collected arising from changes in estimate after acquisition.
Premises and Equipment	Premises and Equipment Premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed primarily using the straight line method over the estimated useful lives of the related assets. Costs incurred for maintenance and repairs are expensed as incurred. The range of estimated useful lives for buildings and improvements is 10 to 40 years, for land improvements, 10 years, and for furniture and equipment, 3 to 10 years. United periodically reviews the carrying value of premises and equipment for impairment whenever events or circumstances indicate that the carrying amount of such assets may not be fully recoverable.
Foreclosed Properties (Other Real Estate Owned)	Foreclosed Properties (Other Real Estate Owned)Foreclosed property is initially recorded at fair value, less cost to sell. If the fair value, less cost to sell at the time of foreclosure is less than the loan balance, the deficiency is recorded as a loan charge-off against the ACL. If the fair value, less cost to sell, of the foreclosed property decreases during the holding period, a valuation allowance is established with a charge to operating expenses. When the foreclosed property is sold, a gain or loss is recognized on the sale for the difference between the sales proceeds and the carrying amount of the property.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill is an asset representing the future economic benefits from other assets acquired that are not individually identified and separately recognized. Goodwill is measured as the excess of the consideration transferred, net of the fair value of identifiable assets acquired and liabilities assumed at the acquisition date. Goodwill is not amortized, but instead is tested for impairment annually or more frequently if events or circumstances exist that indicate a goodwill impairment test should be performed. Other intangible assets, which are initially recorded at fair value, consist of core deposit intangible assets and noncompete agreements resulting from acquisitions. Core deposit intangible assets are amortized on a sum-of-the-years-digits basis over their estimated useful lives. Noncompete agreements, which were fully amortized at December 31, 2019, were amortized on a straight line basis over their estimated useful lives. Management evaluates other intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of the asset may not be recoverable.
Transfers of Financial Assets	Transfers of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been relinquished. Control over transferred assets is deemed to be surrendered when the assets have been isolated from United, the transferee obtains the right, free of conditions that constrain it from taking advantage of that right, to pledge or exchange the transferred assets and United does not maintain effective control over the transferred assets through an agreement to repurchase them before maturity.
Servicing Rights	Servicing Rights United records a separate servicing asset for SBA loans, USDA loans, and residential mortgage loans when the loan is sold but servicing is retained. This asset represents the right to service the loans and receive a fee in compensation. Servicing assets are initially recorded at their fair value as a component of the sale proceeds. The fair value of the servicing assets is based on an analysis of discounted cash flows that incorporates estimates of (1) market servicing costs, (2) market-based prepayment rates, and (3) market profit margins. Servicing assets are included in other assets. United has elected to subsequently measure the servicing assets for government guaranteed loans and residential mortgage loans at fair value. The rate of prepayment of loans serviced is the most significant estimate involved in the measurement process. Estimates of prepayment rates are based on market expectations of future prepayment rates, industry trends, and other considerations. Actual prepayment rates will differ from those projected by management due to changes in a variety of economic factors, including prevailing interest rates and the availability of alternative financing sources to borrowers. If actual prepayments of the loans being serviced were to occur more quickly than projected, the carrying value of servicing assets might have to be written down through a charge to earnings in the current period. If actual prepayments of the loans being serviced were to occur more slowly than had been projected, the carrying value of servicing assets could increase, and servicing income would exceed previously projected amounts. United accounts for the servicing liabilities associated with sold equipment financing loans using the amortization method. Servicing liabilities are included in accrued expenses and other liabilities.
BOLI	BOLI United has purchased life insurance policies on certain key executives and members of management. United has also received life insurance policies on members of acquired bank management teams through acquisitions of other banks. BOLI is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other changes or other amounts due that are probable at settlement.
Operating Leases	Operating Leases Effective January 1, 2019, United records a right-of-use asset, included in other assets, and a related lease liability, included in other liabilities, for eligible operating leases for which it is the lessee, which include leases for land, buildings, and equipment. Payments related to these leases consist primarily of base rent and, in the case of building leases, additional operating costs associated with the leased property such as common area maintenance and utilities. In most cases these operating costs vary over the term of the lease, and therefore are classified as variable lease costs, which are recognized as incurred in the consolidated statement of income. In addition, certain operating leases include costs such as property taxes and insurance, which are recognized as incurred in the consolidated statement of income. Many of United’s operating leases contain renewal options, which are included in the measurement of the right-of-use asset and lease liability only to the extent they are reasonably certain to be exercised. United also subleases and leases certain real estate properties to third parties under operating leases. United does not recognize a lease liability or right-of-use asset on the consolidated balance sheet related to short-term leases with a term of less than one year. Lease payments for short-term leases are recognized as expense over the lease term.
Loan Commitments and Related Financial Instruments	Loan Commitments and Related Financial Instruments Financial instruments include off-balance sheet credit instruments such as commitments to make loans and commercial letters of credit issued to meet customer financing needs. The face amount for these items represents the exposure to loss before considering customer collateral or ability to repay. Such financial instruments are recorded when they are funded.
Revenue from Contracts with Customers	Revenue from Contracts with Customers In addition to lending and related activities, United offers various services to customers that generate revenue, certain of which are governed by ASC Topic 606 Revenue from Contracts with Customers . United’s services that fall within the scope of this topic are presented within noninterest income and include service charges and fees, wealth management fees, and other transaction-based fees. Revenue is recognized when the transactions occur or as services are performed over primarily monthly or quarterly periods. Payment is typically received in the period the transactions occur. Fees may be fixed or, where applicable, based on a percentage of transaction size.
Income Taxes	Income Taxes DTAs and DTLs are recorded for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Future tax benefits are recognized to the extent that realization of such benefits is more likely than not. DTAs and DTLs are measured using enacted tax rates expected to apply to taxable income in the years in which the assets and liabilities are expected to be recovered or settled. The effect of a change in tax rates on DTAs and DTLs is recognized in income taxes during the period that includes the enactment date. In the event the future tax consequences of differences between the financial reporting bases and the tax bases of assets and liabilities results in DTAs, an evaluation of the probability of being able to realize the future benefits indicated by such asset is required. A valuation allowance is provided for the portion of the DTA when it is more likely than not that some or all of the DTA will not be realized. In assessing the realizability of the DTAs, management considers the scheduled reversals of DTLs, projected future taxable earnings and prudent and feasible tax planning strategies. Management weighs both the positive and negative evidence, giving more weight to evidence that can be objectively verified. The income tax benefit or expense is the total of the current year income tax due or refundable and the change in DTAs and DTLs. A tax position is recognized as a benefit only if it is “more likely than not” that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50 percent likely of being realized on examination. For tax positions not meeting the “more likely than not” test, no tax benefit is recorded. United recognizes interest and / or penalties related to income tax matters in income tax expense.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities United’s interest rate risk management strategy incorporates the use of derivative instruments to minimize fluctuations in net income that are caused by interest rate volatility. The objective is to manage interest rate sensitivity by modifying the repricing or maturity characteristics of certain balance sheet assets and liabilities so that net interest revenue and certain interest sensitive components of noninterest revenue are not, on a material basis, adversely affected by movements in interest rates. United views this strategy as a prudent management of interest rate risk, such that net income is not exposed to undue risk presented by changes in interest rates. In carrying out this part of its interest rate risk management strategy, management uses derivatives, primarily interest rate swaps. Interest rate swaps generally involve the exchange of fixed- and variable-rate interest payments between two parties, based on a common notional principal amount and maturity date. United has also occasionally used interest rate caps to serve as an economic macro hedge of exposure to rising interest rates. United originates certain residential mortgage loans with the intention of selling these loans. Between the time United enters into an interest-rate lock commitment to originate a residential mortgage loan that is to be held for sale and the time the loan is funded and eventually sold, the Company is subject to the risk of variability in market prices. United enters into forward sale agreements to mitigate risk and to protect the expected gain on the eventual loan sale. The commitments to originate residential mortgage loans and forward loan sales commitments are freestanding derivative instruments which are entered into as part of an economic hedging strategy to manage exposure related to mortgage loans held for sale. To accommodate customers, United enters into interest rate swaps or caps with certain commercial loan customers, with offsetting positions to dealers under a back-to-back swap/cap program. In addition, United occasionally enters into credit risk participation agreements with counterparty banks to accept a portion of the credit risk related to interest rate swaps. This allows customers to execute an interest rate swap with one bank while allowing for the distribution of the credit risk among participating members. Credit risk participation agreements arise when United contracts with other financial institutions, as a guarantor, to share credit risk associated with certain interest rate swaps. These agreements provide for reimbursement of losses resulting from a third party default on the underlying swap. These transactions are typically executed in conjunction with a participation in a loan with the same customer. Collateral used to support the credit risk for the underlying lending relationship is also available to offset the risk of the credit risk participation. United classifies its derivative financial instruments as either (1) a hedge of an exposure to changes in the fair value of a recorded asset or liability (“fair value hedge”), (2) a hedge of an exposure to changes in the cash flows of a recognized asset, liability or forecasted transaction (“cash flow hedge”), or (3) derivatives not designated as accounting hedges. Changes in the fair value of derivatives not designated as hedges are recognized in current period earnings. United has master netting agreements with the derivatives dealers with which it does business, but reflects gross assets and liabilities at fair value on the consolidated balance sheets. United assesses hedge effectiveness at inception and over the life of the hedge. Management documents, at inception, its analysis of actual and expected hedge effectiveness. This analysis includes techniques such as regression analysis and hypothetical derivatives to demonstrate that the hedge is expected to be highly effective in offsetting corresponding changes in the fair value or cash flows of the hedged item. At least quarterly thereafter, the terms of the hedging instrument and the hedged item are assessed to determine whether a material change has occurred relating to the hedge relationship. If it is determined that a change has occurred, a quantitative analysis as described will occur to determine whether the hedge is expected to be highly effective in offsetting future corresponding changes in the fair value or cash flows of the hedged item. For a qualifying fair value hedge, the changes in the value of derivatives are recognized in current period earnings along with the corresponding changes in the fair value of the designated hedged item attributable to the risk being hedged. For a qualifying cash flow hedge, the changes in the fair value of the derivatives that have been highly effective are recognized in other comprehensive income until the related cash flows from the hedged item are recognized in earnings. For fair value hedges and cash flow hedges, ineffectiveness is recognized in the same income statement line as interest accruals on the hedged item to the extent that changes in the value of the derivative instruments do not perfectly offset changes in the value of the hedged items. If the hedge ceases to be highly effective, United discontinues hedge accounting and recognizes the changes in fair value in current period earnings. If a derivative that qualifies as a fair value or cash flow hedge is terminated or the designation removed, the realized or then unrealized gain or loss is recognized into income over the life of the hedged item (fair value hedge) or over the time when the hedged item was forecasted to impact earnings (cash flow hedge). Immediate recognition in earnings is required upon sale or extinguishment of the hedged item (fair value hedge) or if it is probable that the hedged cash flows will not occur (cash flow hedge). By using derivative instruments, United is exposed to credit and market risk. If the counterparty fails to perform, credit risk is represented by the fair value gain in a derivative. When the fair value of a derivative contract is positive, this situation generally indicates that the counterparty is obligated to pay United, and, therefore, creates a repayment risk for United. When the fair value of a derivative contract is negative, United is obligated to pay the counterparty and, therefore, has no repayment risk. United minimizes the credit risk in non-customer derivative instruments by entering into transactions with high-quality counterparties that are reviewed periodically by management. United also requires non-customer counterparties to pledge cash as collateral to cover the net exposure. All new non-customer derivatives that can be cleared are cleared through a central clearinghouse, which reduces counterparty exposure. Derivative activities are monitored by the ALCO as part its oversight of asset/liability and treasury functions. The ALCO is responsible for implementing various hedging strategies that are developed through its analysis of data from financial simulation models and other internal and industry sources. The resulting hedging strategies are then incorporated into the overall interest-rate risk management process.
Acquisition Activities	Acquisition Activities United accounts for business combinations under the acquisition method of accounting. Assets acquired and liabilities assumed are measured and recorded at fair value at the date of acquisition, including identifiable intangible assets. If the fair value of net assets purchased exceeds the fair value of consideration paid, a bargain purchase gain is recognized at the date of acquisition. Conversely, if the consideration paid exceeds the fair value of the net assets acquired, goodwill is recognized at the acquisition date. Fair values are subject to refinement for a period not to exceed one year after the closing date of an acquisition as information relative to closing date fair values becomes available. Fair values for acquired loans are generally based on a discounted cash flow methodology that considers credit loss expectations, market interest rates and other market factors such as liquidity from the perspective of a market participant. Loans are grouped together according to similar characteristics and are generally treated in the aggregate when applying various valuation techniques. The probability of default, loss given default and prepayment assumptions are the key factors driving credit losses which are embedded into the estimated cash flows. These assumptions are informed by internal data on loan characteristics, historical loss experience, and current and forecasted economic conditions. The interest and liquidity component of the estimate is determined by discounting interest and principal cash flows through the expected life of each loan. The discount rates used for loans are based on current market rates for new originations of comparable loans and include adjustments for liquidity. The discount rate does not include a factor for credit losses as that has been included as a reduction to the estimated cash flows. For additional information about the accounting for purchased loans see PCD Loans (CECL) under the Loans and Leases section of this footnote. All identifiable intangible assets that are acquired in a business combination are recognized at fair value on the acquisition date. Identifiable intangible assets are recognized separately if they arise from contractual or other legal rights or if they are separable (i.e., capable of being sold, transferred, licensed, rented, or exchanged separately from the entity). Deposit liabilities and the related depositor relationship intangible assets may be exchanged in observable exchange transactions. As a result, the depositor relationship intangible asset is considered identifiable, because the separability criterion has been met.
Earnings Per Common Share	Earnings Per Common ShareBasic earnings per common share is net income available to common shareholders divided by the weighted average number of shares of common stock outstanding during the period. All outstanding unvested share-based payment awards that contain rights to nonforfeitable dividends are considered participating securities for this calculation. Additionally, shares issuable to participants in United’s deferred compensation plan are considered to be participating securities for purposes of calculating basic earnings per share. Accordingly, net income available to common shareholders is calculated pursuant to the two-class method, whereby net income after subtracting preferred stock dividends is allocated between common shareholders and participating securities. Diluted earnings per common share includes the dilutive effect of additional potential shares of common stock issuable under stock options, unvested restricted stock units without nonforfeitable rights to dividends, warrants and securities convertible into common stock.
Loss Contingencies	Loss ContingenciesLoss contingencies, including claims and legal actions arising in the ordinary course of business, are recorded as liabilities when the likelihood of loss is probable and an amount or range of loss can be reasonably estimated. Management does not believe there are such matters that will have a material effect on the financial statements.
Dividend Restrictions	Dividend Restrictions Banking regulations require maintaining certain capital levels and may limit dividends paid by the Bank to the Holding Company or by the Holding Company to shareholders. The Board may declare dividends from the Bank to the Holding Company out of retained earnings of up to fifty percent of the Bank’s net income from the previous year without notifying or seeking approval
Fair Value of Financial Instruments	Fair Value of Financial InstrumentsFair values of financial instruments are estimated using relevant market information and other assumptions as more fully disclosed in Note 14. 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 these estimates.
Stock-Based Compensation	Stock-Based CompensationUnited uses the fair value method of recognizing expense for stock-based compensation based on the fair value of option and restricted stock unit awards at the date of grant. United accounts for forfeitures as they occur.
Accounting Standards Updates and Recently Adopted Standards	Recently Adopted Standards On January 1, 2020, United adopted ASC 326 , which replaced the Incurred Loss framework in prior GAAP with a CECL framework. The CECL framework requires an estimate of expected credit losses for the remaining estimated life of the financial asset using historical experience, current conditions, and reasonable and supportable forecasts and generally applies to financial assets measured at amortized cost, including loan receivables and held-to-maturity debt securities, and some off-balance sheet credit exposures such as unfunded commitments to extend credit. Financial assets measured at amortized cost will be presented at the net amount expected to be collected by using an ACL. PCD loans will receive an initial allowance at the acquisition date that represents an adjustment to the amortized cost basis of the loan, with no impact to earnings. Credit losses relating to available-for-sale debt securities will be recorded through an ACL prospectively, with such allowance limited to the amount by which fair value is below amortized cost. United adopted ASC 326 as of January 1, 2020 using the modified retrospective method for loans, leases and off-balance sheet credit exposures. Adoption of this guidance resulted in an $8.75 million increase in the ACL, comprised of increases in the ACL for loans of $6.88 million and the ACL for unfunded commitments of $1.87 million, with $3.59 million of the increase reclassified from the amortized cost basis of PCD financial assets. The cumulative effect adjustment to retained earnings was $3.53 million, net of tax. Calculated credit losses on held-to-maturity debt securities were not material and there was no impact to the available-for-sale securities portfolio or other financial instruments. Results for reporting periods beginning after January 1, 2020 are presented under ASC 326 while prior period amounts continue to be reported in accordance with Incurred Loss. The ACL for the majority of loans and leases was calculated using a discounted cash flow methodology applied at a loan level with a one-year reasonable and supportable forecast period and a two-year straight-line reversion period. In connection with the adoption, management has implemented changes to relevant systems, processes and controls where necessary. United’s CECL allowance will fluctuate over time due to macroeconomic conditions and forecasts as well as the size and composition of the loan portfolios. United has adopted the relief provided by federal banking regulatory agencies for the delay of the adverse capital impact of CECL at adoption and during the subsequent two-year period following adoption. This optional two-year delay is followed by an optional three-year transition period to phase out the aggregate amount of capital benefit provided during the initial two-year delay. Under the transition provision, the amount of aggregate capital benefit is phased out by 25% each year with the full impact of adoption completely recognized by the beginning of the sixth year. United adopted ASC 326 using the prospective transition approach for PCD assets that were previously classified as PCI. In accordance with the standard, management did not reassess whether PCI assets met the criteria of PCD assets as of the date of adoption. As mentioned above, the amortized cost basis of the PCD assets was adjusted to reflect the addition of $3.59 million to the ACL. The remaining noncredit discount (based on the adjusted amortized cost basis) is being accreted into interest income at a rate that approximates the effective interest rate beginning on January 1, 2020. With regard to PCD assets, because United elected to disaggregate the former PCI pools and no longer considers these pools to be the unit of account, contractually delinquent PCD loans are now being reported as nonaccrual loans using the same criteria as other loans. Similarly, although management did not reassess whether modifications to individual acquired financial assets accounted for in pools were TDRs as of the date of adoption, PCD loans that are restructured and meet the definition of TDR after the adoption of ASC 326 are being reported as such. In addition to the aforementioned elections, United made the following elections at adoption: • not to measure an ACL for accrued interest receivable and instead elected to reverse interest income on those loans that are 90 days past due; • to exclude accrued interest receivable from the amortized cost basis of financial instruments subject to ASC 326 and to separately state the balance of accrued interest receivable on the consolidated balance sheet; • to adjust the discount rate used to calculate credit losses for expected prepayments and is including all changes in discounted cash flows as credit loss; and • as a practical expedient, elected to use the fair value of collateral when determining the ACL for loans if repayment is expected to be provided substantially through the operation or sale of the collateral when the borrower is experiencing financial difficulty (collateral-dependent loans). On March 27, 2020, the CARES Act was signed into law, with certain relief extended in December 2020 by the Consolidated Appropriations Act, 2021. Additional COVID-19 pandemic relief was granted by the bank regulatory agencies through a series of interagency statements issued during 2020. The CARES Act, as extended, and the interagency statements include a number of provisions that were applicable to United, including the following: • Accounting Relief for TDRs : The CARES Act provides that modifications under certain forbearance conditions for loans that were not more than 30 days past due at December 31, 2019 will not be considered TDRs for regulatory reporting and GAAP. This exemption period ends on the earlier of January 1, 2022 or the date that is 60 days after the termination date of the national emergency. The interagency statements provide additional relief from TDR status for certain short-term deferrals related to the COVID-19 pandemic for borrowers that were current at the time a modification program was implemented or at the time of the modification itself. • Optional Delay and Regulatory Relief for ASC 326 Adoption : The CARES Act stipulates that large SEC filers have the option of delaying the adoption of ASC 326 from January 1, 2020 to the earlier of the end of the COVID-19 emergency period or December 31, 2020. Banks that were required to implement ASC 326 by the end of 2020 were granted the option to defer any impact on regulatory capital for two years before beginning the original three-year regulatory phase-in period, for a total five-year phase-in period. Although United did not elect to delay the adoption of ASC 326, the Company elected the five-year phase-in period for regulatory capital purposes, as discussed above. • PPP : The CARES Act creates the PPP through the SBA, which allowed United to lend money to small businesses to maintain employee payrolls and pay other qualified expenses during the crisis with guarantees from the SBA. Under this program, loan amounts may be forgiven if the proceeds are used for payroll and other permitted expenses in accordance with the requirements of the PPP. In March 2020, the FASB issued ASU No. 2020-03, Codification Improvements to Financial Instruments . This update clarified certain minor issues within the codification, including, among other things, debt securities disclosure for financial institutions and determination of the contractual term of a net investment in a lease. The standard was effective immediately, and did not have a material impact on the consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting . This update, the scope of which was clarified with ASU No. 2021-01 in January of 2021, provides expedients for contracts that are modified because of reference rate reform, including receivables, debt, leases, and certain derivatives. In addition, the update provides a one-time election to sell or transfer debt securities classified as held-to-maturity that reference a rate that is affected by reference rate reform. The update is effective as of March 12, 2020 through December 31, 2022. At the time of adoption, there was no material impact on the consolidated financial statements, although United anticipates optional expedients adopted such as contract modification and hedge accounting will provide relief otherwise not provided through December 31, 2022. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825 Financial Instruments . In addition to amending guidance related to the new CECL standard, this update clarifies certain aspects of hedge accounting and recognition and measurement of financial instruments. United adopted this update as of January 1, 2020, with no material impact on the consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . This update eliminates Step 2 from the goodwill impairment test, which required an entity to calculate the implied fair value of goodwill by valuing a reporting unit’s assets and liabilities using the same process that would be required to value assets and liabilities in a business combination. Instead, the amendments require that an entity perform its annual goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. United adopted this update as of January 1, 2020, with no material impact on the consolidated financial statements. Accounting Standards Updates Not Yet Adopted as of December 31, 2020 In October 2020, the FASB issued ASU No. 2020-10, Codification Improvements . In addition to consolidating existing disclosure guidance into a single codification section to reduce the likelihood of a required disclosure being missed, this update clarifies the application of select guidance in cases where the original guidance may have been unclear. Adoption of this update, which is effective for United as of January 1, 2021, is not expected to have a material impact on the consolidated financial statements. In October 2020, the FASB issued ASU No. 2020-08, Codification Improvements to Subtopic 310-20, Receivables—Nonrefundable Fees and Other Costs . This update clarifies that an entity should reevaluate whether a callable debt security meets the criteria to adjust the amortization period of any related premium at each reporting period. Adoption of this update, which is effective for United as of January 1, 2021, is not expected to have a material impact on the consolidated financial statements. In January 2020, the FASB issued ASU No. 2020-01, Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)—Clarifying the Interactions between Topic 321, Topic 323, and Topic 815 (a consensus of the Emerging Issues Task Force) . This update clarifies whether an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting for the purposes of applying the measurement alternative and how to account for certain forward contracts and purchased options to purchase securities. For public entities, this guidance is effective for fiscal years beginning after December 15, 2020. United does not expect the new guidance to have a material impact on the consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes . This update removes several exceptions related to intraperiod tax allocation when there is a loss from continuing operations and income from other items, foreign subsidiaries becoming equity method investments and vice versa, and calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. The guidance also amends requirements related to franchise tax that is partially based on income, a step up in the tax basis of goodwill, allocation of consolidated tax expense to a legal entity not subject to tax in its separate financial statements, the effects of enacted changes in tax laws and other minor codification improvements regarding employee stock ownership plans and investments in qualified affordable housing projects. For public entities, this guidance is effective for fiscal years beginning after December 15, 2020. United does not expect the new guidance to have a material impact on the consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans . The update removes disclosures that are no longer considered cost beneficial, clarifies specific requirements of disclosures, and adds disclosure requirements identified as relevant. For public entities, this guidance is effective for fiscal years ending after December 15, 2020 and requires retrospective application to prior periods presented. United does not expect the new guidance to have a material impact on the consolidated financial statements.

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2020
Business Acquisition [Line Items]
Schedule of actual results and pro forma information	The following table presents the actual results and pro forma information for the periods indicated (in thousands) . (Unaudited) Year Ended December 31, Revenue Net Income 2020 Actual Three Shores results included in statement of income since acquisition date $ 24,541 $ 6,800 Supplemental consolidated pro forma as if Three Shores had been acquired January 1, 2019 597,729 168,717 2019 Actual FMBT results included in statement of income since acquisition date $ 7,525 $ 4,053 Supplemental consolidated pro forma as if Three Shores had been acquired on January 1, 2019 and FMBT had been acquired January 1, 2018 636,079 210,232 2018 Actual Navitas results included in the statement of income since acquisition date $ 24,285 $ 7,149 Supplemental consolidated pro forma as if FMBT had been acquired January 1, 2018 and Navitas had been acquired January 1, 2017 539,152 171,218
Three Shores
Business Acquisition [Line Items]
Schedule of purchased assets and assumed liabilities	The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 219,807 Debt securities 381,740 Loans 1,427,966 Premises and equipment, net 1,584 Accrued interest receivable 7,681 Derivative assets 11,800 Net deferred tax asset 15,061 Core deposit intangible 3,360 Other assets 65,340 Total assets acquired 2,134,339 Liabilities Deposits 1,802,694 FHLB advances and long-term debt 144,121 Derivative liabilities 12,165 Other liabilities 28,046 Total liabilities assumed 1,987,026 Total identifiable net assets 147,313 Consideration transferred Cash 24,108 Common stock issued (8,130,633 shares) 163,589 Total fair value of consideration transferred 187,697 Goodwill $ 40,384
Schedule of additional information related to acquired loan portfolio	The following table presents additional information related to the acquired loan portfolio at the acquisition date (in thousands) : July 1, 2020 PCD loans: Par Value $ 283,137 ACL at acquisition (11,152) Non-credit discount (8,694) Purchase price $ 263,291 Non-PCD loans: Fair value $ 1,164,675 Gross contractual amounts receivable 1,358,793 Estimate of contractual cash flows not expected to be collected 76,503
FMBT
Business Acquisition [Line Items]
Schedule of purchased assets and assumed liabilities	The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 32,548 Loans 192,494 Premises and equipment, net 8,524 BOLI 6,823 Net deferred tax asset 157 Core deposit intangible 2,800 Other assets 1,278 Total assets acquired 244,624 Liabilities Deposits 212,127 Other liabilities 717 Total liabilities assumed 212,844 Total identifiable net assets 31,780 Cash consideration transferred 52,093 Goodwill $ 20,313
Schedule of additional information related to acquired loan portfolio	The following table presents additional information related to the acquired loan portfolio at the acquisition date (in thousands) : May 1, 2019 PCI loans: Contractually required principal and interest $ 13,145 Non-accretable difference 2,517 Cash flows expected to be collected 10,628 Accretable yield 1,300 Fair value $ 9,328 Non-PCI loans: Fair value $ 183,166 Gross contractual amounts receivable 218,855 Estimate of contractual cash flows not expected to be collected 8,826
Navitas
Business Acquisition [Line Items]
Schedule of purchased assets and assumed liabilities	The purchased assets and assumed liabilities were recorded at their acquisition date fair values and are summarized in the table below (in thousands) . Fair Value Recorded by United Assets Cash and cash equivalents $ 27,700 Loans and leases, net 358,352 Premises and equipment, net 324 Net deferred tax asset 2,873 Other assets 4,051 Total assets acquired 393,300 Liabilities Short-term borrowings 214,923 Long-term debt 119,402 Other liabilities 16,108 Total liabilities assumed 350,433 Total identifiable net assets 42,867 Consideration transferred Cash 84,500 Common stock issued (1,443,987 shares) 45,746 Total fair value of consideration transferred 130,246 Goodwill $ 87,379
Schedule of additional information related to acquired loan portfolio	The following table presents additional information related to the acquired loan and lease portfolio at the acquisition date (in thousands) . February 1, 2018 PCI loans: Contractually required principal and interest $ 24,711 Non-accretable difference 5,505 Cash flows expected to be collected 19,206 Accretable yield 1,977 Fair value $ 17,229 Non-PCI loans: Fair value $ 341,123 Gross contractual amounts receivable 389,432 Estimate of contractual cash flows not expected to be collected 8,624

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Schedule of cost basis, unrealized gains and losses, and fair value of debt securities held-to-maturity	The cost basis, unrealized gains and losses, and fair value of debt securities held-to-maturity as of the dates indicated are as follows (in thousands) : Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value As of December 31, 2020 U.S. Government agencies & GSEs $ 10,575 $ 26 $ 11 $ 10,590 State and political subdivisions 197,723 7,658 242 205,139 Residential mortgage-backed, Agency & GSE 113,400 4,774 1 118,173 Commercial mortgage-backed, Agency & GSE 98,663 4,874 246 103,291 Total $ 420,361 $ 17,332 $ 500 $ 437,193 As of December 31, 2019 State and political subdivisions $ 45,479 $ 1,574 $ 9 $ 47,044 Residential mortgage-backed, Agency & GSE 153,967 2,014 694 155,287 Commercial mortgage-backed, Agency & GSE 84,087 1,627 141 85,573 Total $ 283,533 $ 5,215 $ 844 $ 287,904
Schedule of cost basis, unrealized gains and losses, and fair value of debt securities available-for-sale	The cost basis, unrealized gains and losses, and fair value of debt securities available-for-sale as of the dates indicated are as follows (in thousands): Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value As of December 31, 2020 U.S. Treasuries $ 123,677 $ 4,395 $ — $ 128,072 U.S. Government agencies & GSEs 152,596 701 325 152,972 State and political subdivisions 253,630 20,891 49 274,472 Residential mortgage-backed, Agency & GSE 1,275,551 29,107 766 1,303,892 Residential mortgage-backed, Non-agency 174,322 7,499 128 181,693 Commercial mortgage-backed, Agency & GSE 524,852 8,013 597 532,268 Commercial mortgage-backed, Non-agency 15,350 1,513 — 16,863 Corporate bonds 70,057 1,711 1 71,767 Asset-backed securities 562,076 1,278 632 562,722 Total $ 3,152,111 $ 75,108 $ 2,498 $ 3,224,721 As of December 31, 2019 U.S. Treasuries $ 152,990 $ 1,628 $ — $ 154,618 U.S. Government agencies & GSEs 2,848 188 1 3,035 State and political subdivisions 214,677 11,813 — 226,490 Residential mortgage-backed, Agency & GSE 1,030,948 12,022 726 1,042,244 Residential mortgage-backed, Non-agency 250,550 6,231 — 256,781 Commercial mortgage-backed, Agency & GSE 266,770 2,261 128 268,903 Commercial mortgage-backed, Non-agency 15,395 918 263 16,050 Corporate bonds 202,131 1,178 218 203,091 Asset-backed securities 104,298 743 1,672 103,369 Total $ 2,240,607 $ 36,982 $ 3,008 $ 2,274,581
Schedule of debt securities held to maturity in an unrealized loss position	The following summarizes debt securities held-to-maturity in an unrealized loss position as of the dates indicated (in thousands) : Less than 12 Months 12 Months or More Total Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized As of December 31, 2020 U.S. Government agencies & GSEs $ 4,677 $ 11 $ — $ — $ 4,677 $ 11 State and political subdivisions 14,870 242 — — 14,870 242 Residential mortgage-backed, Agency & GSE 999 1 — — 999 1 Commercial mortgage-backed, Agency & GSE 24,956 236 1,352 10 26,308 246 Total unrealized loss position $ 45,502 $ 490 $ 1,352 $ 10 $ 46,854 $ 500 As of December 31, 2019 State and political subdivisions $ 10,117 $ 9 $ — $ — $ 10,117 $ 9 Residential mortgage-backed, Agency & GSE 16,049 64 48,237 630 64,286 694 Commercial mortgage-backed, Agency & GSE 21,841 87 1,685 54 23,526 141 Total unrealized loss position $ 48,007 $ 160 $ 49,922 $ 684 $ 97,929 $ 844
Schedule of debt securities available for sale in an unrealized loss position	The following summarizes debt securities available-for-sale in an unrealized loss position as of the dates indicated (in thousands) : Less than 12 Months 12 Months or More Total Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized As of December 31, 2020 U.S. Government agencies & GSEs $ 27,952 $ 324 $ 607 $ 1 $ 28,559 $ 325 State and political subdivisions 9,402 49 — — 9,402 49 Residential mortgage-backed, Agency & GSE 232,199 766 — — 232,199 766 Residential mortgage-backed, Non-agency 2,331 128 — — 2,331 128 Commercial mortgage-backed, Agency & GSE 89,918 597 — — 89,918 597 Corporate bonds 1,410 1 — — 1,410 1 Asset-backed securities 87,305 28 53,587 604 140,892 632 Total unrealized loss position $ 450,517 $ 1,893 $ 54,194 $ 605 $ 504,711 $ 2,498 As of December 31, 2019 U.S. Government agencies & GSEs $ 404 $ 1 $ — $ — $ 404 $ 1 Residential mortgage-backed, Agency & GSE 228,611 576 18,294 150 246,905 726 Commercial mortgage-backed, Agency & GSE — — 33,517 128 33,517 128 Commercial mortgage-backed, Non-agency — — 4,864 263 4,864 263 Corporate bonds 19,742 216 998 2 20,740 218 Asset-backed securities 32,294 625 38,990 1,047 71,284 1,672 Total unrealized loss position $ 281,051 $ 1,418 $ 96,663 $ 1,590 $ 377,714 $ 3,008
Schedule of available-for-sale securities sales activity	Realized gains and losses are derived using the specific identification method for determining the cost of the securities sold. The following summarizes securities sales activities for the years ended December 31 (in thousands) : 2020 2019 2018 Proceeds from sales $ 40,625 $ 352,106 $ 168,891 Gross gains on sales $ 748 $ 1,843 $ 2,082 Gross losses on sales — (2,864) (2,738) Net gains (losses) on sales of securities $ 748 $ (1,021) $ (656) Income tax expense (benefit) attributable to sales $ 191 $ (247) $ (132)
Schedule of amortized cost and fair value of available-for-sale and held-to-maturity securities by contractual maturity	The amortized cost and fair value of debt available-for-sale and held-to-maturity securities at December 31, 2020, by contractual maturity, are presented in the following table (in thousands). Expected maturities may differ from contractual maturities because issuers and borrowers may have the right to call or prepay obligations. Available-for-Sale Held-to-Maturity Amortized Cost Fair Value Amortized Cost Fair Value Within 1 year: U.S. Treasuries $ 20,014 $ 20,311 $ — $ — U.S. Government agencies & GSEs 201 201 — — State and political subdivisions 20,020 20,232 1,700 1,743 Corporate bonds 11,441 11,592 — — 51,676 52,336 1,700 1,743 1 to 5 years: U.S. Treasuries 103,663 107,761 — — U.S. Government agencies & GSEs 16,710 16,820 — — State and political subdivisions 48,354 51,544 14,505 16,059 Corporate bonds 44,636 45,837 — — 213,363 221,962 14,505 16,059 5 to 10 years: U.S. Government agencies & GSEs 55,588 55,481 — — State and political subdivisions 59,837 64,843 7,028 7,957 Corporate bonds 13,206 13,485 — — 128,631 133,809 7,028 7,957 More than 10 years: U.S. Government agencies & GSEs 80,097 80,470 10,575 10,590 State and political subdivisions 125,419 137,853 174,490 179,380 Corporate bonds 774 853 — — 206,290 219,176 185,065 189,970 Debt securities not due at a single maturity: Asset-backed securities 562,076 562,722 — — Residential mortgage-backed securities 1,449,873 1,485,585 113,400 118,173 Commercial mortgage-backed securities 540,202 549,131 98,663 103,291 Total $ 3,152,111 $ 3,224,721 $ 420,361 $ 437,193

Loans and Leases and Allowanc_2

Loans and Leases and Allowance for Credit Losses (Tables)	12 Months Ended
	Dec. 31, 2020
Receivables [Abstract]
Schedule of major classifications of loans and lease portfolio	Major classifications of the loan and lease portfolio (collectively referred to as the “loan portfolio” or “loans”) are summarized as of the dates indicated as follows (in thousands) : December 31, 2020 2019 Owner occupied commercial real estate $ 2,090,443 $ 1,720,227 Income producing commercial real estate 2,540,750 2,007,950 Commercial & industrial (1) 2,498,560 1,220,657 Commercial construction 967,305 976,215 Equipment financing 863,830 744,544 Total commercial 8,960,888 6,669,593 Residential mortgage 1,284,920 1,117,616 Home equity lines of credit 697,117 660,675 Residential construction 281,430 236,437 Consumer 146,460 128,232 Total loans 11,370,815 8,812,553 Less ACL - loans (137,010) (62,089) Loans, net $ 11,233,805 $ 8,750,464 (1) Commercial and industrial loans as of December 31, 2020 included $646 million o
Schedule of loans sold	The following table presents loans sold by United for the periods presented (in thousands). The gains and losses on these loan sales were included in noninterest income on the consolidated statements of income. Loans Sold 2020 2019 2018 Guaranteed portion of SBA/USDA loans $ 48,385 $ 81,158 $ 120,977 Equipment financing receivables 27,018 30,952 — Indirect auto loans — 102,789 — Total $ 75,403 $ 214,899 $ 120,977
Schedule of components of net investment in leases	At December 31, 2020 and 2019, equipment financing assets included leases of $36.8 million and $37.4 million, respectively. The components of the net investment in leases, which included both sales-type and direct financing, are presented below (in thousands) . December 31, 2020 2019 Minimum future lease payments receivable $ 38,934 $ 39,709 Estimated residual value of leased equipment 3,263 3,631 Initial direct costs 672 842 Security deposits (727) (989) Purchase accounting premium 117 273 Unearned income (5,457) (6,088) Net investment in leases $ 36,802 $ 37,378
Schedule of minimum future lease payments expected to be received from equipment financing lease contracts	Minimum future lease payments expected to be received from equipment financing lease contracts as of December 31, 2020 were as follows (in thousands) : Year 2021 $ 15,152 2022 11,516 2023 7,452 2024 3,429 2025 1,341 Thereafter 44 Total $ 38,934
Schedule of loans by aging category and accrual status	The following table presents the amortized cost basis in loans by aging category and accrual status as of December 31, 2020 (in thousands). Short-term deferrals of approximately $70.7 million related to the COVID-19 crisis are not reported as past due during the deferral period. Accruing Loans Past Due Current Loans 30 - 59 Days 60 - 89 Days > 90 Days Nonaccrual Loans Total Loans As of December 31, 2020 Owner occupied commercial real estate $ 2,079,845 $ 2,013 $ 3 $ — $ 8,582 $ 2,090,443 Income producing commercial real estate 2,522,743 1,608 1,250 — 15,149 2,540,750 Commercial & industrial 2,480,483 1,176 267 — 16,634 2,498,560 Commercial construction 964,947 231 382 — 1,745 967,305 Equipment financing 856,985 2,431 1,009 — 3,405 863,830 Total commercial 8,905,003 7,459 2,911 — 45,515 8,960,888 Residential mortgage 1,265,019 5,549 1,494 — 12,858 1,284,920 Home equity lines of credit 692,504 1,942 184 — 2,487 697,117 Residential construction 280,551 365 — — 514 281,430 Consumer 145,770 429 36 — 225 146,460 Total loans $ 11,288,847 $ 15,744 $ 4,625 $ — $ 61,599 $ 11,370,815 The following table presents the aging of recorded investment in loans, including accruing and nonaccrual loans, as of December 31, 2019 (in thousands). Loans Past Due - Accrual and Non-accrual As of December 31, 2019 30 - 59 Days 60 - 89 Days > 90 Days (1) Total Current Loans PCI Loans Total Owner occupied commercial real estate $ 2,913 $ 2,007 $ 6,079 $ 10,999 $ 1,700,682 $ 8,546 $ 1,720,227 Income producing commercial real estate 562 706 401 1,669 1,979,053 27,228 2,007,950 Commercial & industrial 2,140 491 2,119 4,750 1,215,581 326 1,220,657 Commercial construction 1,867 557 96 2,520 966,833 6,862 976,215 Equipment financing 2,065 923 3,045 6,033 734,526 3,985 744,544 Total commercial 9,547 4,684 11,740 25,971 6,596,675 46,947 6,669,593 Residential mortgage 5,655 2,212 2,171 10,038 1,097,999 9,579 1,117,616 Home equity lines of credit 1,697 421 1,385 3,503 655,762 1,410 660,675 Residential construction 325 125 402 852 235,211 374 236,437 Consumer 668 181 27 876 127,020 336 128,232 Total loans $ 17,892 $ 7,623 $ 15,725 $ 41,240 $ 8,712,667 $ 58,646 $ 8,812,553 ( 1) Excluding PCI loans, substantially all loans more than 90 days past due were on nonaccrual status at December 31, 2019.
Schedule of nonaccrual loans by loan class	The following table presents nonaccrual loans by loan class for the periods indicated (in thousands) . Nonaccrual loans CECL Incurred Loss December 31, 2020 December 31, 2019 With no allowance With an allowance Total Owner occupied commercial real estate $ 6,614 $ 1,968 $ 8,582 $ 10,544 Income producing commercial real estate 10,008 5,141 15,149 1,996 Commercial & industrial 2,004 14,630 16,634 2,545 Commercial construction 1,339 406 1,745 2,277 Equipment financing 156 3,249 3,405 3,141 Total commercial 20,121 25,394 45,515 20,503 Residential mortgage 1,855 11,003 12,858 10,567 Home equity lines of credit 1,329 1,158 2,487 3,173 Residential construction 274 240 514 939 Consumer 181 44 225 159 Total $ 23,760 $ 37,839 $ 61,599 $ 35,341
Schedule of risk category of loans by vintage year or class of loans	Based on the most recent analysis performed, the amortized cost of loans by risk category by vintage year as of December 31, 2020 is as follows (in thousands) : Term Loans by Origination Year Revolvers Revolvers converted to term loans Total December 31, 2020 2020 2019 2018 2017 2016 Prior Pass Owner occupied commercial real estate $ 707,501 $ 368,615 $ 231,316 $ 197,778 $ 201,362 $ 229,667 $ 56,273 $ 9,072 $ 2,001,584 Income producing commercial real estate 815,799 376,911 361,539 277,769 206,068 198,080 28,542 12,128 2,276,836 Commercial & industrial 1,092,767 287,857 263,439 115,790 92,968 58,359 515,593 3,777 2,430,550 Commercial construction 314,154 217,643 226,308 53,708 30,812 21,985 20,278 3,947 888,835 Equipment financing 413,653 270,664 125,869 39,982 9,404 445 — — 860,017 Total commercial 3,343,874 1,521,690 1,208,471 685,027 540,614 508,536 620,686 28,924 8,457,822 Residential mortgage 468,945 195,213 125,492 120,944 122,013 230,771 18 5,393 1,268,789 Home equity lines of credit — — — — — — 675,878 17,581 693,459 Residential construction 225,727 30,646 4,026 4,544 3,172 12,546 — 64 280,725 Consumer 54,997 25,528 14,206 4,531 3,595 1,677 41,445 76 146,055 4,093,543 1,773,077 1,352,195 815,046 669,394 753,530 1,338,027 52,038 10,846,850 Watch Owner occupied commercial real estate 8,759 4,088 4,221 10,025 11,138 4,728 100 — 43,059 Income producing commercial real estate 35,471 42,831 39,954 13,238 24,164 11,337 — 1,681 168,676 Commercial & industrial 1,451 16,315 2,176 630 459 17 6,464 — 27,512 Commercial construction 21,366 272 816 23,292 11,775 477 — — 57,998 Equipment financing — — — — — — — — — Total commercial 67,047 63,506 47,167 47,185 47,536 16,559 6,564 1,681 297,245 Residential mortgage — — — — — — — — — Home equity lines of credit — — — — — — — — — Residential construction — — — — — — — — — Consumer — — — — — — — — — 67,047 63,506 47,167 47,185 47,536 16,559 6,564 1,681 297,245 Substandard Owner occupied commercial real estate 6,586 10,473 7,596 3,717 6,753 8,473 1,528 674 45,800 Income producing commercial real estate 45,125 8,940 2,179 5,034 31,211 2,652 — 97 95,238 Commercial & industrial 1,545 5,536 6,193 1,684 1,292 1,485 22,170 593 40,498 Commercial construction 2,466 735 13,741 340 1,931 250 — 1,009 20,472 Equipment financing 631 1,392 1,371 306 96 17 — — 3,813 Total commercial 56,353 27,076 31,080 11,081 41,283 12,877 23,698 2,373 205,821 Residential mortgage 2,049 2,106 3,174 1,369 679 5,860 — 894 16,131 Home equity lines of credit — — — — — — 265 3,393 3,658 Residential construction 106 37 54 4 124 380 — — 705 Consumer — 97 49 60 78 98 — 23 405 58,508 29,316 34,357 12,514 42,164 19,215 23,963 6,683 226,720 Total $ 4,219,098 $ 1,865,899 $ 1,433,719 $ 874,745 $ 759,094 $ 789,304 $ 1,368,554 $ 60,402 $ 11,370,815 The following table presents the risk category of loans by class of loan as of December 31, 2019 (in thousands) : As of December 31, 2019 Pass Watch Substandard Doubtful / Total Owner occupied commercial real estate $ 1,638,398 $ 24,563 $ 48,720 $ — $ 1,711,681 Income producing commercial real estate 1,914,524 40,676 25,522 — 1,980,722 Commercial & industrial 1,156,366 16,385 47,580 — 1,220,331 Commercial construction 960,251 2,298 6,804 — 969,353 Equipment financing 737,418 — 3,141 — 740,559 Total commercial 6,406,957 83,922 131,767 — 6,622,646 Residential mortgage 1,093,902 — 14,135 — 1,108,037 Home equity lines of credit 654,619 — 4,646 — 659,265 Residential construction 234,791 — 1,272 — 236,063 Consumer 127,507 8 381 — 127,896 Total loans, excluding PCI loans 8,517,776 83,930 152,201 — 8,753,907 Owner occupied commercial real estate 3,238 2,797 2,511 — 8,546 Income producing commercial real estate 19,648 6,305 1,275 — 27,228 Commercial & industrial 104 81 141 — 326 Commercial construction 3,628 590 2,644 — 6,862 Equipment financing 3,952 — 33 — 3,985 Total commercial 30,570 9,773 6,604 — 46,947 Residential mortgage 8,112 — 1,467 — 9,579 Home equity lines of credit 1,350 — 60 — 1,410 Residential construction 348 — 26 — 374 Consumer 303 — 33 — 336 Total PCI loans 40,683 9,773 8,190 — 58,646 Total loan portfolio $ 8,558,459 $ 93,703 $ 160,391 $ — $ 8,812,553
Schedule of changes in the value of the accretable yield for PCI loans	The following table presents changes in the value of the accretable yield for PCI loans for the year ended December 31, 2019 (in thousands) : Balance at beginning of period $ 26,868 Additions due to acquisitions 1,300 Accretion (17,885) Reclassification from nonaccretable difference 9,237 Changes in expected cash flows that do not affect nonaccretable difference 4,400 Balance at end of period $ 23,920
Schedule of loans modified under the terms of a TDR	Loans modified under the terms of a TDR during the years ended December 31 are presented in the table below. In addition, the following table presents loans modified under the terms of a TDR that defaulted (became 90 days or more delinquent) during the years ended December 31 that were initially restructured within one year prior to default (dollars in thousands) : New TDRs Number of Post-Modification Outstanding Recorded Investment TDRs Modified Within the Year That Have Subsequently Defaulted Year Ended December 31, 2020 Rate Structure Other Total Number of Contracts Recorded Owner occupied commercial real estate 8 $ — $ 833 $ 1,536 $ 2,369 — $ — Income producing commercial real estate 7 — 4,856 6,699 11,555 1 5,998 Commercial & industrial 4 — 586 15 601 3 819 Commercial construction 7 — 832 70 902 — — Equipment financing 172 — 5,821 5,821 22 944 Total commercial 198 — 12,928 8,320 21,248 26 7,761 Residential mortgage 40 — 4,359 3 4,362 2 145 Home equity lines of credit 4 — 164 — 164 1 60 Residential construction 3 — 123 — 123 — — Consumer 7 — 11 24 35 1 3 Total loans 252 $ — $ 17,585 $ 8,347 $ 25,932 30 $ 7,969 Year Ended December 31, 2019 Owner occupied commercial real estate 4 $ — $ 1,739 $ — $ 1,739 — $ — Income producing commercial real estate 3 — 9,013 — 9,013 — — Commercial & industrial 2 — 75 7 82 — — Commercial construction — — — — — — — Equipment financing 9 — 1,071 — 1,071 — — Total commercial 18 — 11,898 7 11,905 — — Residential mortgage 15 — 2,057 — 2,057 1 135 Home equity lines of credit 1 — 50 — 50 — — Residential construction 1 — — 21 21 1 13 Consumer 5 — — 45 45 — — Indirect auto 15 — — 262 262 — — Total loans 55 $ — $ 14,005 $ 335 $ 14,340 2 $ 148 Year Ended December 31, 2018 Owner occupied commercial real estate 5 $ — $ 1,387 $ — $ 1,387 3 $ 1,869 Income producing commercial real estate 2 106 3,637 — 3,743 — — Commercial & industrial 2 — 32 — 32 1 232 Commercial construction — — — — — 1 3 Equipment financing — — — — — — — Total commercial 9 106 5,056 — 5,162 5 2,104 Residential mortgage 15 130 1,770 — 1,900 1 101 Home equity lines of credit 1 — — 41 41 — — Residential construction 2 — 32 13 45 — — Consumer 2 — — 7 7 — — Indirect auto 35 — — 643 643 — — Total loans 64 $ 236 $ 6,858 $ 704 $ 7,798 6 $ 2,205
Schedule of balance and activity in the ACL by portfolio segment	The following table presents the balance and activity in the ACL by portfolio segment for the periods indicated (in thousands) : CECL Year Ended December 31, 2020 Dec. 31, 2019 Adoption of CECL Jan. 1, 2020 Initial ACL- PCD loans (1) Charge-Offs Recoveries Provision Ending Owner occupied commercial $ 11,404 $ (1,616) $ 9,788 $ 1,779 $ (70) $ 2,565 $ 6,611 $ 20,673 Income producing commercial 12,306 (30) 12,276 1,208 (8,430) 3,546 33,137 41,737 Commercial & industrial 5,266 4,012 9,278 7,680 (10,707) 1,371 14,397 22,019 Commercial construction 9,668 (2,583) 7,085 74 (726) 1,045 3,474 10,952 Equipment financing 7,384 5,871 13,255 — (8,764) 2,004 10,325 16,820 Residential mortgage 8,081 1,569 9,650 195 (398) 455 5,439 15,341 Home equity lines of credit 4,575 1,919 6,494 209 (221) 677 1,258 8,417 Residential construction 2,504 (1,771) 733 — (93) 156 (32) 764 Consumer 901 (491) 410 7 (2,985) 2,259 596 287 ACL - loans 62,089 6,880 68,969 11,152 (32,394) 14,078 75,205 137,010 ACL - unfunded commitments 3,458 1,871 5,329 — — — 5,229 10,558 Total ACL $ 65,547 $ 8,751 $ 74,298 $ 11,152 $ (32,394) $ 14,078 $ 80,434 $ 147,568 (1) Represents the initial ACL related to PCD loans acquired in the Three Shores transaction. Incurred Loss Year Ended December 31, 2019 Beginning Charge-Offs Recoveries Provision Ending Owner occupied commercial real estate $ 12,207 $ (5) $ 375 $ (1,173) $ 11,404 Income producing commercial real estate 11,073 (1,227) 283 2,177 12,306 Commercial & industrial 4,802 (5,849) 852 5,461 5,266 Commercial construction 10,337 (290) 1,165 (1,544) 9,668 Equipment financing 5,452 (5,675) 781 6,826 7,384 Residential mortgage 8,295 (616) 481 (79) 8,081 Home equity lines of credit 4,752 (996) 610 209 4,575 Residential construction 2,433 (306) 157 220 2,504 Consumer 853 (2,390) 911 1,527 901 Indirect auto 999 (663) 186 (522) — ACL - loans 61,203 (18,017) 5,801 13,102 62,089 ACL - unfunded commitments 3,410 — — 48 3,458 Total ACL $ 64,613 $ (18,017) $ 5,801 $ 13,150 $ 65,547 Incurred Loss Year Ended December 31, 2018 Beginning Charge-Offs Recoveries Provision Ending Owner occupied commercial real estate $ 14,776 $ (303) $ 1,227 $ (3,493) $ 12,207 Income producing commercial real estate 9,381 (3,304) 1,064 3,932 11,073 Commercial & industrial 3,971 (1,669) 1,390 1,110 4,802 Commercial construction 10,523 (622) 734 (298) 10,337 Equipment financing — (1,536) 460 6,528 5,452 Residential mortgage 10,097 (754) 336 (1,384) 8,295 Home equity lines of credit 5,177 (1,194) 423 346 4,752 Residential construction 2,729 (54) 376 (618) 2,433 Consumer 710 (2,445) 807 1,781 853 Indirect auto 1,550 (1,277) 228 498 999 ACL - loans 58,914 (13,158) 7,045 8,402 61,203 ACL - unfunded commitments 2,312 — — 1,098 3,410 Total ACL $ 61,226 $ (13,158) $ 7,045 $ 9,500 $ 64,613 The following table presents the recorded investment in loans by portfolio segment and the balance of the ACL assigned to each segment based on the method of evaluating the loans for impairment as of December 31, 2019 (in thousands) : Loans Outstanding Allowance for Credit Losses Individually Collectively PCI Ending Individually Collectively PCI Ending Owner occupied commercial real estate $ 19,233 $ 1,692,448 $ 8,546 $ 1,720,227 $ 816 $ 10,483 $ 105 $ 11,404 Income producing commercial real estate 18,134 1,962,588 27,228 2,007,950 770 11,507 29 12,306 Commercial & industrial 1,449 1,218,882 326 1,220,657 21 5,193 52 5,266 Commercial construction 3,675 965,678 6,862 976,215 55 9,613 — 9,668 Equipment financing 1,027 739,532 3,985 744,544 — 7,240 144 7,384 Residential mortgage 15,991 1,092,046 9,579 1,117,616 782 7,296 3 8,081 Home equity lines of credit 992 658,273 1,410 660,675 16 4,541 18 4,575 Residential construction 1,256 234,807 374 236,437 47 2,456 1 2,504 Consumer 214 127,682 336 128,232 5 885 11 901 Total ACL - loans $ 61,971 $ 8,691,936 $ 58,646 $ 8,812,553 2,512 59,214 363 62,089 ACL - unfunded commitments — 3,458 — 3,458 Total ACL $ 2,512 $ 62,672 $ 363 $ 65,547
Schedule of loans individually evaluated for impairment under Incurred Loss by class	The following table presents loans individually evaluated for impairment by class of loans as of the dates indicated (in thousands) : December 31, 2019 Unpaid Principal Balance Recorded Investment ACL Allocated With no related ACL recorded: Owner occupied commercial real estate $ 9,527 $ 8,118 $ — Income producing commercial real estate 5,159 4,956 — Commercial & industrial 1,144 890 — Commercial construction 2,458 2,140 — Equipment financing 1,027 1,027 — Total commercial 19,315 17,131 — Residential mortgage 7,362 6,436 — Home equity lines of credit 1,116 861 — Residential construction 731 626 — Consumer 66 53 — Total with no related ACL recorded 28,590 25,107 — With an ACL recorded: Owner occupied commercial real estate 11,136 11,115 816 Income producing commercial real estate 13,591 13,178 770 Commercial & industrial 559 559 21 Commercial construction 1,535 1,535 55 Equipment financing — — — Total commercial 26,821 26,387 1,662 Residential mortgage 9,624 9,555 782 Home equity lines of credit 146 131 16 Residential construction 643 630 47 Consumer 161 161 5 Total with an ACL recorded 37,395 36,864 2,512 Total $ 65,985 $ 61,971 $ 2,512
Schedule of average balances of impaired loans and income recognized on impaired loans while they were considered impaired	The average balances of impaired loans and income recognized on impaired loans while they were considered impaired is presented below for the periods indicated (in thousands) : 2019 2018 Average Interest Cash Basis Average Interest Cash Basis Owner occupied commercial $ 18,575 $ 1,124 $ 1,171 $ 19,881 $ 1,078 $ 1,119 Income producing commercial 14,253 739 730 17,138 893 895 Commercial & industrial 1,837 84 100 1,777 100 100 Commercial construction 3,233 129 146 3,247 176 174 Equipment financing 159 23 23 — — — Total commercial 38,057 2,099 2,170 42,043 2,247 2,288 Residential mortgage 16,115 748 749 14,515 641 643 Home equity lines of credit 488 14 15 284 18 16 Residential construction 1,332 92 94 1,405 96 95 Consumer 203 15 15 249 18 18 Indirect auto 1,028 50 50 1,252 64 64 Total $ 57,223 $ 3,018 $ 3,093 $ 59,748 $ 3,084 $ 3,124

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of premises and equipment	Premises and equipment are summarized as follows as of the dates indicated (in thousands) : December 31, 2020 2019 Land and land improvements $ 82,816 $ 81,150 Buildings and improvements 173,497 170,629 Furniture and equipment 96,157 97,997 Construction in progress 7,590 1,701 360,060 351,477 Less accumulated depreciation (141,571) (135,501) Premises and equipment, net $ 218,489 $ 215,976

Derivatives and Hedging Activ_2

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative financial instruments on consolidated balance sheet	The table below presents the fair value of derivative financial instruments as of the dates indicated as well as their classification on the consolidated balance sheets (in thousands) : December 31, 2020 December 31, 2019 Notional Amount Fair Value Fair Value Derivative Assets Derivative Liabilities Derivative Assets Derivative Liabilities Derivatives designated as hedging instruments: Cash flow hedge of subordinated debt $ 100,000 $ 3,378 $ — $ — $ — Cash flow hedge of trust preferred securities 20,000 — — — — Fair value hedge of brokered CDs 20,000 — — — 880 Total 140,000 3,378 — — 880 Derivatives not designated as hedging instruments: Customer derivative positions 1,329,271 72,508 17 27,277 446 Dealer offsets to customer derivative positions 1,329,271 1 24,614 394 6,425 Risk participations 48,843 28 12 — 12 Mortgage banking - loan commitment 253,243 10,751 — 1,970 — Mortgage banking - forward sales commitment 325,145 — 1,964 98 86 Bifurcated embedded derivatives 51,935 — 1,449 5,268 — Dealer offsets to bifurcated embedded derivatives 51,935 — 947 — 7,667 Total 3,389,643 83,288 29,003 35,007 14,636 Total derivatives $ 3,529,643 $ 86,666 $ 29,003 $ 35,007 $ 15,516 Total gross derivative instruments $ 86,666 $ 29,003 $ 35,007 $ 15,516 Less: Amounts subject to master netting agreements (114) (114) (401) (401) Less: Cash collateral received/pledged (3,200) (27,092) — (14,933) Net amount $ 83,352 $ 1,797 $ 34,606 $ 182
Schedule of effect of derivatives in hedging relationships consolidated statements of income	The table below presents the effect of derivatives in hedging relationships on the consolidated statements of income (in thousands) . Year Ended December 31, 2020 2019 2018 Interest expense Interest expense Interest expense Interest revenue - taxable investment securities Other noninterest income Total income (expense) presented in the $ (56,237) $ (83,312) $ (61,330) $ 73,496 $ 24,142 Gains (losses) on fair value hedging relationships: Interest rate contracts: Amounts related to interest settlements 291 (327) (245) 17 — Recognized on derivatives 870 733 (220) — 356 Recognized on hedged items (880) (766) (145) — (447) Net income (expense) recognized on fair value hedges $ 281 $ (360) $ (610) $ 17 $ (91) Losses on cash flow hedging relationships (1) : Interest rate contracts: Realized losses reclassified from AOCI into net income (2) $ (359) $ — $ — $ — $ — Net expense recognized on cash flow hedges $ (359) $ — $ — $ — $ — (1) Excludes 2019 and 2018 amortization of losses related to de-designated cash flow hedges. See Note 17 for further detail. (2) Includes $329,000 of premium amortization expense excluded from the assessment of hedge effectiveness for the year ended December 31, 2020.
Schedule of carrying amount and cumulative fair value hedging adjustments on hedged liability	The table below presents the carrying amount of hedged fixed-rate brokered time deposits and cumulative fair value hedging adjustments included in the carrying amount of the hedged liability for the periods presented (in thousands) . December 31, 2020 2019 Balance Sheet Location Carrying amount of Assets (Liabilities) Hedge Accounting Basis Adjustment Carrying amount of Assets (Liabilities) Hedge Accounting Basis Adjustment Deposits $ (20,216) $ (235) $ (35,880) $ 645
Schedule of gains and losses recognized in income on derivatives not designated as hedging instruments	The table below presents the gains and losses recognized in income on derivatives not designated as hedging instruments for the periods indicated (in thousands) . Income Statement Location Year Ended December 31, 2020 2019 2018 Customer derivatives and dealer offsets Other noninterest income $ 6,732 $ 2,878 $ 2,658 Bifurcated embedded derivatives and dealer offsets Other noninterest income (63) 212 307 Interest rate caps Other noninterest income — — 501 De-designated hedges Other noninterest income — (193) 31 Mortgage banking derivatives Mortgage loan revenue (7,873) (1,797) 904 Risk participations Other noninterest income (340) (3) 12 Total gains and losses $ (1,544) $ 1,097 $ 4,413

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of carrying amount of goodwill and other intangible assets	The carrying amount of goodwill and other intangible assets is summarized below as of the dates indicated (in thousands) : December 31, 2020 2019 Core deposit intangible $ 36,162 $ 32,802 Less: accumulated amortization (22,148) (17,980) Net core deposit intangible 14,014 14,822 Goodwill 367,809 327,425 Total goodwill and other intangible assets, net $ 381,823 $ 342,247
Schedule of changes in the carrying amounts of goodwill	The following is a summary of changes in the carrying amounts of goodwill for the years indicated (in thousands) : Goodwill (1) December 31, 2018 $ 307,112 Acquisition of FMBT 20,313 December 31, 2019 327,425 Acquisition of Three Shores 40,384 December 31, 2020 $ 367,809 (1) Goodwill balances presented are shown net of accumulated impairment losses of $306 million incurred prior to 2018. Gross goodwill for December 31, 2020, 2019, and 2018 totaled $673 million, $633 million and $613 million, respectively.
Schedule of amortization expense for future periods	The estimated aggregate amortization expense for future periods for core deposit intangibles is as follows (in thousands) : Year 2021 $ 3,622 2022 2,915 2023 2,321 2024 1,834 2025 1,414 Thereafter 1,908 Total $ 14,014

Servicing Assets and Liabilit_2

Servicing Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2020
Transfers and Servicing [Abstract]
Schedule of changes in SBA/USDA servicing rights	The following table summarizes the changes in SBA/USDA servicing rights for the years indicated ( in thousands ). 2020 2019 2018 Servicing rights for SBA/USDA loans, beginning of period $ 6,794 $ 7,510 $ 7,740 Originated servicing rights capitalized upon sale of loans 1,114 1,835 2,573 Disposals (624) (1,258) (810) Measurement period adjustment to acquired servicing rights — — (354) Changes in fair value due to change in inputs or assumptions used in the valuation (822) (1,293) (1,639) Servicing rights for SBA/USDA loans, end of period $ 6,462 $ 6,794 $ 7,510
Schedule of key characteristics, inputs, and economic assumptions used to estimate the fair value of SBA/USDA loans servicing asset and sensitivity	A summary of the key characteristics, inputs, and economic assumptions used in the discounted cash flow method utilized to estimate the fair value of the servicing asset for SBA/USDA loans and the sensitivity of the fair values to immediate adverse changes in those assumptions are shown in the table below as of the dates indicated (dollars in thousands) : December 31, 2020 2019 Fair value of retained servicing assets $ 6,462 $ 6,794 Prepayment rate assumption: Weighted average 17.8 % 16.5 % Range 2.7% - 33.6% 10% adverse change $ (358) $ (352) 20% adverse change (680) (671) Discount rate: Weighted average 8.9 % 12.3 % Range 1.6% - 44.1% 100 bps adverse change $ (171) $ (184) 200 bps adverse change (333) (358) Life (in years): Weighted-average 3.5 3.9 Range 0.6 - 5.6 Gross margin: Weighted-average 1.9 % 1.9 % Range 0.0% - 3.2%
Schedule of changes in residential mortgage servicing rights	The following table summarizes the changes in residential mortgage servicing rights for the years indicated ( in thousands ). 2020 2019 2018 Residential mortgage servicing rights, beginning of period $ 13,565 $ 11,877 $ 8,262 Originated servicing rights capitalized upon sale of loans 11,911 5,783 4,587 Disposals (2,868) (1,098) (537) Changes in fair value due to change in inputs or assumptions used in the valuation (6,392) (2,997) (435) Residential mortgage servicing rights, end of period $ 16,216 $ 13,565 $ 11,877
Schedule of key characteristics, inputs, and economic assumptions used to estimate the fair value of residential mortgage loans servicing asset and sensitivity	A summary of the key characteristics, inputs, and economic assumptions used to estimate the fair value of the servicing asset for residential mortgage loans and the sensitivity of the fair values to immediate adverse changes in those assumptions are shown in the table below as of the dates indicated (in thousands) : December 31, 2020 2019 Fair value of retained servicing assets $ 16,216 $ 13,565 Prepayment rate assumption: Weighted average 17.7 % 14.1 % Range 8.7% - 19.5% 10% adverse change $ (999) $ (662) 20% adverse change (1,912) (1,270) Discount rate: Weighted average 10.0 % 10.0 % Range 10.0% - 11.0% 100 bps adverse change $ (518) $ (467) 200 bps adverse change (1,001) (900)

Time Deposits (Tables)

Time Deposits (Tables)	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Schedule of contractual maturities of time deposits, including brokered time deposits	At December 31, 2020, the contractual maturities of time deposits, including brokered time deposits, are summarized as follows (in thousands) : 2021 $ 1,418,807 2022 211,523 2023 59,153 2024 25,513 2025 20,816 Thereafter 50,579 Total time deposits $ 1,786,391

Long-term Debt (Tables)

Long-term Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of long-term debt	Long-term debt consisted of the following (in thousands) : December 31, Issue Date Stated Maturity Date Earliest Call Date 2020 2019 Interest Rate Obligations of the Bank: 2026 subordinated debentures $ 15,000 $ — 2016 2026 2021 5.875% through August 2021, 3-month LIBOR plus 4.70% thereafter 15,000 — Obligations of the Holding Company: 2022 senior debentures 50,000 50,000 2015 2022 2020 5.000% through August 2020, 3-month LIBOR plus 3.814% thereafter 2027 senior debentures 35,000 35,000 2015 2027 2025 5.500% through August 2025, 3-month LIBOR plus 3.71% thereafter 2030 senior debentures 100,000 — 2020 2030 2025 5.00% through June 2025, 3-month SOFR plus 4.87% thereafter Total senior debentures 185,000 85,000 2028 subordinated debentures 100,000 100,000 2018 2028 2023 4.500% through January 2023, 3-month LIBOR plus 2.12% thereafter 2025 subordinated debentures 11,250 11,250 2015 2025 2020 6.250% Total subordinated debentures 111,250 111,250 Southern Bancorp Capital Trust I 4,382 4,382 2004 2034 2009 Prime + 1.00% Tidelands Statutory Trust I 8,248 8,248 2006 2036 2011 3-month LIBOR plus 1.38% Four Oaks Statutory Trust I 12,372 12,372 2006 2036 2011 3-month LIBOR plus 1.35% Total trust preferred securities 25,002 25,002 Less net discount (9,296) (8,588) Total long-term debt $ 326,956 $ 212,664

Operating Leases (Tables)

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Schedule of right-of-use asset and operating lease liability	The following table presents the balances of the right-of-use asset and corresponding operating lease liability as of the dates indicated (in thousands). December 31, Balance Sheet Location 2020 2019 Right-of-use asset Other assets $ 31,398 $ 19,894 Operating lease liability Other liabilities 33,095 22,039
Schedule of operating lease income and expense and other supplemental information	The table below presents the operating lease income and expense recognized for the periods indicated (in thousands). Income Statement Location 2020 2019 Operating lease cost Occupancy expense $ 6,449 $ 5,067 Variable lease cost Occupancy expense 757 449 Short-term lease cost Occupancy expense 100 136 Total lease cost $ 7,306 $ 5,652 Sublease income and rental income from owned properties under operating leases Other noninterest income $ 1,022 $ 1,160
Schedule of future minimum lease payments under operating leases	As of December 31, 2020, future minimum lease payments under operating leases were as follows (in thousands) : Year 2021 $ 7,446 2022 7,544 2023 6,953 2024 3,417 2025 2,403 Thereafter 6,996 Total 34,759 Less discount (1,664) Present value of lease liability $ 33,095

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of assets and liabilities measured at fair value on a recurring basis	The table below presents United’s assets and liabilities measured at fair value on a recurring basis, aggregated by the level in the fair value hierarchy within which those measurements fall (in thousands) : December 31, 2020 Level 1 Level 2 Level 3 Total Assets: Debt securities available for sale: U.S. Treasuries $ 128,072 $ — $ — $ 128,072 U.S. Government agencies & GSEs — 152,972 — 152,972 State and political subdivisions — 274,472 — 274,472 Residential mortgage-backed securities — 1,485,585 — 1,485,585 Commercial mortgage-backed securities — 549,131 — 549,131 Corporate bonds — 70,017 1,750 71,767 Asset-backed securities — 562,722 — 562,722 Equity securities with readily determinable fair values 774 913 — 1,687 Mortgage loans held for sale — 105,433 — 105,433 Deferred compensation plan assets 9,584 — — 9,584 Servicing rights for SBA/USDA loans — — 6,462 6,462 Residential mortgage servicing rights — — 16,216 16,216 Derivative financial instruments — 75,887 10,779 86,666 Total assets $ 138,430 $ 3,277,132 $ 35,207 $ 3,450,769 Liabilities: Deferred compensation plan liability $ 9,590 $ — $ — $ 9,590 Derivative financial instruments — 26,595 2,408 29,003 Total liabilities $ 9,590 $ 26,595 $ 2,408 $ 38,593 December 31, 2019 Level 1 Level 2 Level 3 Total Assets: Securities available for sale: U.S. Treasuries $ 154,618 $ — $ — $ 154,618 U.S. Government agencies & GSEs — 3,035 — 3,035 State and political subdivisions — 226,490 — 226,490 Residential mortgage-backed securities — 1,299,025 — 1,299,025 Commercial mortgage-backed securities — 284,953 — 284,953 Corporate bonds — 202,093 998 203,091 Asset-backed securities — 103,369 — 103,369 Equity securities with readily determinable fair values 1,973 — — 1,973 Mortgage loans held for sale — 58,484 — 58,484 Deferred compensation plan assets 8,133 — — 8,133 Servicing rights for SBA/USDA loans — — 6,794 6,794 Residential mortgage servicing rights — — 13,565 13,565 Derivative financial instruments — 27,769 7,238 35,007 Total assets $ 164,724 $ 2,205,218 $ 28,595 $ 2,398,537 Liabilities: Deferred compensation plan liability $ 8,132 $ — $ — $ 8,132 Derivative financial instruments — 6,957 8,559 15,516 Total liabilities $ 8,132 $ 6,957 $ 8,559 $ 23,648
Schedule of assets measured at fair value on a recurring basis using significant unobservable inputs	The following table shows a reconciliation of the beginning and ending balances for all other assets measured at fair value on a recurring basis using significant unobservable inputs that are classified as Level 3 values (in thousands) : Derivative Derivative Debt Securities December 31, 2017 $ 12,207 $ 16,744 $ 900 Sales and settlements (1,029) (1,347) — Other comprehensive income — — 95 Amounts included in earnings - fair value adjustments 663 335 — December 31, 2018 11,841 15,732 995 Sales and settlements (1,135) (2,330) — Other comprehensive income — — 3 Amounts included in earnings - fair value adjustments (3,468) (4,843) — December 31, 2019 7,238 8,559 998 Transfers into Level 3 583 — — Additions 368 — 1,750 Sales and settlements — — (1,000) Other comprehensive income — — 2 Amounts included in earnings - fair value adjustments 2,590 (6,151) — December 31, 2020 $ 10,779 $ 2,408 $ 1,750
Schedule of liabilities measured at fair value on a recurring basis using significant unobservable inputs	The following table shows a reconciliation of the beginning and ending balances for all other assets measured at fair value on a recurring basis using significant unobservable inputs that are classified as Level 3 values (in thousands) : Derivative Derivative Debt Securities December 31, 2017 $ 12,207 $ 16,744 $ 900 Sales and settlements (1,029) (1,347) — Other comprehensive income — — 95 Amounts included in earnings - fair value adjustments 663 335 — December 31, 2018 11,841 15,732 995 Sales and settlements (1,135) (2,330) — Other comprehensive income — — 3 Amounts included in earnings - fair value adjustments (3,468) (4,843) — December 31, 2019 7,238 8,559 998 Transfers into Level 3 583 — — Additions 368 — 1,750 Sales and settlements — — (1,000) Other comprehensive income — — 2 Amounts included in earnings - fair value adjustments 2,590 (6,151) — December 31, 2020 $ 10,779 $ 2,408 $ 1,750
Schedule of quantitative information about Level 3 fair value measurements for fair value on a recurring basis	The following table presents quantitative information about recurring Level 3 fair value measurements, excluding servicing rights which are detailed in Note 10 (in thousands) : Valuation Technique December 31, Level 3 Assets Unobservable Inputs 2020 2019 Low High Weighted Average Weighted Average Corporate bonds Indicative bid provided by a broker Multiple factors, including but not limited to, current operations, financial condition, cash flows, and similar financing transactions executed in the market N/A N/A N/A N/A Derivative assets - mortgage Internal model Pull through rate 65.6% 100% 83.9% 83.6% Derivative assets - customer derivative positions Internal model Probability of default rate & loss given default 100 100 100 N/A Derivative assets & liabilities - risk participations Internal model Probable exposure rate 0.06 3.66 1.81 0.36 Probability of default rate 0.16 13.1 4.03 1.80 Derivative assets & liabilities - other Dealer priced Dealer priced N/A N/A N/A N/A
Schedule of loans held for sale at fair value under the fair value option	The following tables present the fair value and outstanding principal balance of these loans, as well as the gain or loss recognized resulting from the change in fair value for the periods indicated (in thousands) . Mortgage Loans Held for Sale December 31, 2020 2019 Outstanding principal balance $ 99,746 $ 56,613 Fair value 105,433 58,484 Amount of Gain (Loss) Recognized on Location 2020 2019 2018 Mortgage loan gains and other related fees $ 3,815 $ 1,177 $ (133)
Schedule of presentation of assets measured at fair value on nonrecurring basis	The following table presents the fair value hierarchy and carrying value of all assets that were still held as of December 31, 2020 and 2019, for which a nonrecurring fair value adjustment was recorded during the periods presented (in thousands) . December 31, 2020 Level 1 Level 2 Level 3 Total Loans $ — $ — $ 29,404 $ 29,404 December 31, 2019 Loans $ — $ — $ 20,977 $ 20,977
Schedule of carrying amount and fair values for other financial instruments that are not measured at fair value on a recurring basis	The carrying amount and fair values for other financial instruments that are not measured at fair value on a recurring basis in United’s consolidated balance sheets are as follows (in thousands) : Carrying Amount Fair Value Level December 31, 2020 Level 1 Level 2 Level 3 Total Assets: Securities held to maturity $ 420,361 $ — $ 437,193 $ — $ 437,193 Loans, net 11,233,805 — — 11,209,717 11,209,717 Liabilities: Deposits 15,232,358 — 15,232,274 — 15,232,274 Long-term debt 326,956 — — 336,763 336,763 December 31, 2019 Assets: Securities held to maturity $ 283,533 $ — $ 287,904 $ — $ 287,904 Loans, net 8,750,464 — — 8,714,592 8,714,592 Liabilities: Deposits 10,897,244 — 10,897,465 — 10,897,465 Long-term debt 212,664 — — 217,665 217,665

Equity Compensation Plans (Tabl

Equity Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of restricted stock units and options outstanding and activity	Restricted stock units and options outstanding and activity for the years ended December 31 consisted of the following: Restricted Stock Units Options Shares Weighted Average Grant Date Fair Value Aggregate Shares Weighted Average Exercise Price December 31, 2017 663,817 $ 22.40 60,287 $ 24.12 Granted 416,484 30.54 — — Vested / Exercised (290,013) 20.18 (12,000) 11.85 Cancelled (30,542) 23.65 (1,148) 31.50 December 31, 2018 759,746 27.66 47,139 27.07 Granted 315,827 26.74 — — Vested / Exercised (216,138) 25.38 (13,000) 16.34 Expired — (30,243) 31.43 Cancelled (51,011) 27.18 (2,396) 29.68 December 31, 2019 808,424 27.94 1,500 27.95 Granted 446,512 19.15 — — Vested / Exercised (324,697) 26.42 $ 7,212 — — Expired — (1,500) 27.95 Cancelled (36,808) 25.73 — — December 31, 2020 893,431 23.75 25,409 —

Reclassifications Out of AOCI (

Reclassifications Out of AOCI (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Schedule of details regarding amounts reclassified out of AOCI	The following presents the details regarding amounts reclassified out of AOCI (in thousands). Amounts Reclassified from AOCI For the Years Ended December 31, Details about AOCI Components Affected Line Item in the Statement Where Net Income is Presented 2020 2019 2018 Realized gains (losses) on available-for-sale securities: $ 748 $ (1,021) $ (656) Securities gains (losses), net (191) 247 132 Income tax (expense) benefit $ 557 $ (774) $ (524) Net of tax Amortization of losses included in net income on available-for-sale securities transferred to held to maturity: $ (723) $ (383) $ (739) Investment securities interest revenue 173 92 180 Income tax benefit $ (550) $ (291) $ (559) Net of tax Reclassifications related to derivative financial instruments accounted for as cash flow hedges: Amortization of losses on de-designated positions $ — $ (235) $ — Other expense Amortization of losses on de-designated positions — (102) (499) Deposit interest expense Interest rate contracts (359) — — Long-term debt interest expense (359) (337) (499) Total before tax 91 86 129 Income tax benefit $ (268) $ (251) $ (370) Net of tax Reclassifications related to defined benefit pension plan activity: Prior service cost $ (531) $ (640) $ (666) Salaries and employee benefits expense Actuarial losses (326) (59) (241) Other expense Termination of Funded Plan — (1,558) — Merger-related and other (857) (2,257) (907) Total before tax 219 576 247 Income tax benefit $ (638) $ (1,681) $ (660) Net of tax Total reclassifications for the period $ (899) $ (2,997) $ (2,113) Net of tax Amounts shown above in parentheses reduce earnings

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of computation of basic and diluted net income per common share	The following table sets forth the computation of basic and diluted net income per common share for the years indicated (in thousands, except per share data) : Year Ended December 31, 2020 2019 2018 Net income $ 164,089 $ 185,721 $ 166,111 Undistributed earnings allocated to participating securities (1,287) (1,375) (1,184) Dividends on preferred stock (3,533) — — Net income available to common stockholders $ 159,269 $ 184,346 $ 164,927 Net income per common share: Basic $ 1.91 $ 2.31 $ 2.07 Diluted 1.91 2.31 2.07 Weighted average common shares: Basic 83,184 79,700 79,662 Effect of dilutive securities: Stock options — 1 7 Restricted stock units 64 7 2 Diluted 83,248 79,708 79,671

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of income tax expense	Income tax expense is as follows for the years indicated (in thousands) : Year Ended December 31, 2020 2019 2018 Current $ 42,688 $ 38,082 $ 17,185 Deferred 2,668 14,909 32,630 Total income tax expense $ 45,356 $ 52,991 $ 49,815
Schedule of differences between the provision for income taxes and statutory federal income tax rate	The differences between the provision for income taxes and the amount computed by applying the statutory federal income tax rate of 21% in 2020, 2019 and 2018 to income before income taxes are as follows for the years indicated (in thousands) : Year Ended December 31, 2020 2019 2018 Pretax income at statutory rates $ 43,983 $ 50,130 $ 45,344 Add (deduct): State taxes, net of federal benefit 5,928 7,168 6,765 BOLI earnings (1,052) (1,127) (747) Adjustment to reserve for uncertain tax positions (1,212) 84 80 Tax-exempt interest revenue (2,169) (1,827) (1,229) Equity compensation (174) (375) (892) Transaction costs 217 16 78 Tax credit investments (930) (464) (29) Change in state statutory tax rate — — 583 Other 765 (614) (138) Total income tax expense $ 45,356 $ 52,991 $ 49,815
Schedule of summarizes the sources and expected tax consequences of future taxable deductions (revenue)	The following summarizes the sources and expected tax consequences of future taxable deductions (revenue) which comprise the net DTA as of the dates indicated (in thousands) : December 31, 2020 2019 DTAs: ACL $ 33,213 $ 14,910 Net operating loss carryforwards 22,277 27,568 Deferred compensation 10,012 9,363 Loan purchase accounting adjustments 8,567 6,599 Reserve for losses on foreclosed properties 33 20 Nonqualified share based compensation 1,833 2,041 Accrued expenses 6,865 3,958 Investment in partnerships 71 67 Unamortized pension actuarial losses and prior service cost 1,981 1,739 Securities purchase accounting adjustments — 687 Lease liability 8,055 5,327 Other 4,018 1,351 Total DTAs 96,925 73,630 DTLs: Unrealized gains on securities available-for-sale 17,439 7,943 Unrealized gains on cash flow hedges 54 — Acquired intangible assets 2,576 2,530 Premises and equipment 4,241 3,002 Loan origination costs 4,857 3,538 True tax leases 7,846 7,783 Prepaid expenses 230 373 Servicing assets 4,816 4,428 Derivatives 2,250 1,075 Right-of-use asset 7,642 4,809 Securities purchase accounting adjustments 3,146 — Uncertain tax positions 1,813 1,792 Total DTLs 56,910 37,273 Less valuation allowance 1,604 2,298 Net DTA $ 38,411 $ 34,059
Schedule of reconciliation of the beginning and ending unrecognized tax benefit related to uncertain tax positions	A reconciliation of the beginning and ending unrecognized tax benefit related to uncertain tax positions is as follows for the years indicated (in thousands) : 2020 2019 2018 Balance at beginning of year $ 3,370 $ 3,264 $ 3,163 Additions based on tax positions related to the current year 421 481 470 Decreases resulting from a lapse in the applicable statute of limitations (1,628) (375) (369) Balance at end of year $ 2,163 $ 3,370 $ 3,264

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Schedule of weighted-average assumptions used to determine pension benefit obligations	Weighted-average assumptions used to determine the pension benefit obligation of the Modified Retirement Plan at year end and net periodic pension cost are shown in the table below: 2020 2019 Discount rate for disclosures 2.55 % 3.25 % Discount rate for net periodic benefit cost 3.25 % 4.40 % Measurement date 12/31/2020 12/31/2019
Schedule of changes in obligations and plan assets	United recognizes the underfunded status of the plans as a liability in the consolidated balance sheets. Information about changes in obligations and plan assets follows (in thousands) : 2020 2019 Modified Modified Funded Accumulated benefit obligation: Accumulated benefit obligation - beginning of year $ 25,105 $ 21,736 $ 16,011 Service cost 588 392 — Interest cost 795 931 166 Plan amendments — 386 — Actuarial losses 1,804 2,390 1,489 Benefits paid (1,193) (730) (17,666) Accumulated benefit obligation - end of year 27,099 25,105 — Change in plan assets, at fair value: Beginning plan assets — — 12,595 Actual return — — 173 Employer contribution 1,193 730 4,898 Benefits paid (1,193) (730) (17,666) Plan assets - end of year — — — Funded status - end of year (plan assets less benefit obligations) $ (27,099) $ (25,105) $ —
Schedule of components of net periodic benefit cost and other amounts recognized in other comprehensive income	Components of net periodic benefit cost and other amounts recognized in other comprehensive income are as follows (in thousands): 2020 2019 2018 Modified Modified Funded Modified Funded Service cost $ 588 $ 392 $ — $ 363 $ — Interest cost 795 931 166 801 647 Expected return on plan assets — — (106) — (551) Amortization of prior service cost 531 635 — 666 — Amortization of net actuarial losses 326 59 — 241 — Net periodic benefit cost $ 2,240 $ 2,017 $ 60 $ 2,071 $ 96
Schedule of estimated future benefit payments expected to be paid	The following table summarizes the estimated future benefit payments expected to be paid from the Modified Retirement Plan for the periods indicated (in thousands) . 2021 $ 1,170 2022 1,165 2023 1,159 2024 1,152 2025 1,195 2026-2030 7,675

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2020
Regulatory Capital Requirements Under Banking Regulations [Abstract]
Schedule of minimum amounts required for capital adequacy purposes	Regulatory capital ratios at December 31, 2020 and 2019, along with the minimum amounts required for capital adequacy purposes and to be well-capitalized under prompt corrective action provisions in effect at such times are presented below for United and the Bank (dollars in thousands) : Basel III Guidelines United Community Banks, Inc. United Community Bank Minimum (1) Well 2020 2019 2020 2019 Risk-based ratios: CET1 capital 4.5 % 6.5 % 12.31 % 12.97 % 13.31 % 14.87 % Tier 1 capital 6.0 8.0 13.10 13.21 13.31 14.87 Total capital 8.0 10.0 15.15 15.01 14.28 15.54 Tier 1 leverage ratio 4.0 5.0 9.28 10.34 9.42 11.63 CET1 capital $ 1,506,750 $ 1,275,148 $ 1,625,292 $ 1,458,720 Tier 1 capital 1,603,172 1,299,398 1,625,292 1,458,720 Total capital 1,854,368 1,476,302 1,743,045 1,524,267 RWAs 12,240,440 9,834,051 12,207,940 9,810,477 Average total assets 17,276,853 12,568,563 17,246,878 12,545,254 (1) As of December 31, 2020 and 2019, the additional capital conservation buffer in effect was 2.50%.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of the contract amount of off-balance sheet instruments	The following table summarizes, as of the dates indicated, the contract amount of off-balance sheet instruments (in thousands) : December 31, 2020 2019 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit $ 3,052,657 $ 2,126,275 Letters of credit 31,748 22,533

Condensed Financial Statement_2

Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only) (Tables)	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Schedule of condensed balance sheets	Balance Sheets As of December 31, 2020 and 2019 (in thousands) 2020 2019 Assets Cash and cash equivalents $ 289,243 $ 32,495 Investment in bank 2,028,965 1,814,414 Investment in other subsidiaries 752 752 Other assets 34,661 29,308 Total assets $ 2,353,621 $ 1,876,969 Liabilities and Shareholders’ Equity Long-term debt $ 311,956 $ 212,664 Other liabilities 34,135 28,613 Total liabilities 346,091 241,277 Shareholders’ equity 2,007,530 1,635,692 Total liabilities and shareholders’ equity $ 2,353,621 $ 1,876,969
Schedule of condensed statements of income	Statements of Income For the Years Ended December 31, 2020, 2019 and 2018 (in thousands) 2020 2019 2018 Dividends from bank $ 150,000 $ — $ 161,500 Dividends from other subsidiaries — 4,651 850 Shared service fees from subsidiaries 13,020 14,721 10,257 Other 1,436 1,468 133 Total income 164,456 20,840 172,740 Interest expense 13,994 11,573 11,868 Other expense 16,473 18,965 14,456 Total expenses 30,467 30,538 26,324 Income tax benefit 2,681 8,711 1,640 Income (loss) before equity in undistributed earnings of subsidiaries 136,670 (987) 148,056 Equity in undistributed earnings of subsidiaries 27,419 186,708 18,055 Net income $ 164,089 $ 185,721 $ 166,111
Schedule of condensed statements of cash flows	Statements of Cash Flows For the Years Ended December 31, 2020, 2019 and 2018 (in thousands) 2020 2019 2018 Operating activities: Net income $ 164,089 $ 185,721 $ 166,111 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of the subsidiaries (27,419) (186,708) (18,055) Stock-based compensation 7,887 9,360 6,057 Change in assets and liabilities: Other assets (3,662) (3,022) 1,777 Other liabilities 5,261 2,080 3,124 Net cash provided by operating activities 146,156 7,431 159,014 Investing activities: Net cash received (paid) for acquisition 3,397 (52,093) (84,499) Purchases of premises and equipment — — (364) Purchases of debt securities available-for-sale and equity securities (2,750) (3,000) (2,489) Proceeds from sales and maturities of debt securities available-for-sale and equity securities — 83 — Net cash provided by (used in) investing activities 647 (55,010) (87,352) Financing activities: Repayment of long-term debt — (250) (7,424) Proceeds from issuance of long-term debt, net of issuance costs 98,552 — 98,188 Proceeds from issuance of preferred stock, net of issuance costs 96,422 — — Cash related to shares withheld to cover payroll taxes upon vesting of restricted stock units (3,119) (1,686) (1,998) Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans 1,317 2,193 679 Proceeds from exercise of stock options — 212 142 Repurchase of common stock (20,782) (13,020) — Cash dividends on preferred stock (3,533) — — Cash dividends on common stock (58,912) (53,044) (41,634) Net cash provided by (used in) financing activities 109,945 (65,595) 47,953 Net change in cash 256,748 (113,174) 119,615 Cash at beginning of year 32,495 145,669 26,054 Cash at end of year $ 289,243 $ 32,495 $ 145,669

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2020USD ($)segment	Dec. 31, 2019USD ($)
Accounting Policies [Line Items]
Number of operating segments | segment	1
Number of reportable segments | segment	1
Accrued interest receivable	$ 47,672,000	$ 32,660,000
Investment in FHLB stock	13,300,000
Minimum nonaccrual loan relationships for reserve evaluation	500,000
Loans receivable
Accounting Policies [Line Items]
Accrued interest receivable	35,500,000
Held-to-maturity debt securities
Accounting Policies [Line Items]
Accrued interest receivable	1,780,000
Available-for-sale debt securities
Accounting Policies [Line Items]
Accrued interest receivable	$ 9,110,000
Buildings and improvements | Minimum
Accounting Policies [Line Items]
Estimated useful life (in years)	10 years
Buildings and improvements | Maximum
Accounting Policies [Line Items]
Estimated useful life (in years)	40 years
Land improvements
Accounting Policies [Line Items]
Estimated useful life (in years)	10 years
Furniture and equipment | Minimum
Accounting Policies [Line Items]
Estimated useful life (in years)	3 years
Furniture and equipment | Maximum
Accounting Policies [Line Items]
Estimated useful life (in years)	10 years
Loan Portfolio | Credit Concentration Risk
Accounting Policies [Line Items]
Concentration risk, percentage	69.00%

Accounting Standards Updates _2

Accounting Standards Updates and Recently Adopted Standards (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in ACL		$ 147,568	$ 65,547	$ 64,613	$ 61,226
Increase in ACL for loans		137,010	62,089	61,203	58,914
Increase in ACL for unfunded commitments		10,558	3,458	3,410	2,312
Reduction in equity		(2,007,530)	(1,635,692)	(1,457,554)	(1,303,334)
Retained earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reduction in equity		$ (136,869)	(40,152)	90,419	$ 209,902
Adoption of new accounting standard
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in ACL			8,751
Increase in ACL for loans			6,880
Increase in ACL for unfunded commitments			1,871
Reduction in equity			3,529	549
Adoption of new accounting standard | Retained earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reduction in equity			3,529	$ 549
ASU No. 2016-13 | Adoption of new accounting standard
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in ACL			8,750
Increase in ACL for loans			6,880
Increase in ACL for unfunded commitments			1,870
Increase reclassified from amortized cost basis of PCD financial assets previously classified as PCI	$ 3,590
ASU No. 2016-13 | Adoption of new accounting standard | Retained earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reduction in equity			$ 3,530

Mergers and Acquisitions - Narr

Mergers and Acquisitions - Narrative (Details)	Jul. 01, 2020USD ($)bank_branchshares	May 01, 2019USD ($)bank_branch	Feb. 01, 2018USD ($)shares	Jan. 31, 2018USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Business Acquisition [Line Items]
Goodwill					$ 367,809,000	$ 367,809,000	$ 327,425,000	$ 307,112,000
Merger-related and other charges						7,018,000	6,907,000	5,414,000
Three Shores
Business Acquisition [Line Items]
Number of banking offices | bank_branch	14
Assets acquired	$ 2,134,339,000
Liabilities assumed	1,987,026,000
Total consideration	187,697,000
Common stock issued in acquisition	163,589,000
Cash consideration	$ 24,108,000
Shares issued in acquisition (in shares) | shares	8,130,633
Goodwill	$ 40,384,000
Goodwill expected to be tax deductible	0
Intangible assets acquired	3,360,000
Measurement period adjustment increase to cash and cash equivalents					1,090,000
Measurement period adjustment increase to accrued interest receivable					116,000
Goodwill adjustment increase (decrease)					$ (1,210,000)
Three Shores | Merger-related costs
Business Acquisition [Line Items]
Merger-related and other charges						$ 5,040,000
Three Shores | Core deposit intangible
Business Acquisition [Line Items]
Intangible assets acquired	$ 3,360,000
Expected useful life of acquired intangible (in years)	10 years
FMBT
Business Acquisition [Line Items]
Number of banking offices | bank_branch		4
Assets acquired		$ 244,624,000
Liabilities assumed		212,844,000
Cash consideration		52,093,000
Goodwill		20,313,000
Goodwill expected to be tax deductible		0
Intangible assets acquired		2,800,000
FMBT | Merger-related costs
Business Acquisition [Line Items]
Merger-related and other charges							$ 2,020,000
FMBT | Core deposit intangible
Business Acquisition [Line Items]
Intangible assets acquired		$ 2,800,000
Expected useful life of acquired intangible (in years)		9 years 3 months
Navitas
Business Acquisition [Line Items]
Assets acquired			$ 393,300,000
Liabilities assumed			350,433,000
Total consideration			130,246,000
Common stock issued in acquisition			45,746,000
Cash consideration			$ 84,500,000
Shares issued in acquisition (in shares) | shares			1,443,987
Goodwill			$ 87,379,000
Goodwill expected to be tax deductible			$ 0
Value of loans acquired separate from the business combination				$ 19,900,000
Navitas | Merger-related costs
Business Acquisition [Line Items]
Merger-related and other charges								$ 4,980,000

Mergers and Acquisitions - Acqu

Mergers and Acquisitions - Acquisition date fair value of purchased assets and assumed liabilities (Details) - USD ($) $ in Thousands	Jul. 01, 2020	May 01, 2019	Feb. 01, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consideration transferred
Goodwill				$ 367,809	$ 327,425	$ 307,112
Three Shores
Assets
Cash and cash equivalents	$ 219,807
Debt securities	381,740
Loans and leases, net	1,427,966
Premises and equipment, net	1,584
Accrued interest receivable	7,681
Derivative assets	11,800
Net deferred tax asset	15,061
Core deposit intangible	3,360
Other assets	65,340
Total assets acquired	2,134,339
Liabilities
Deposits	1,802,694
FHLB advances and long-term debt	144,121
Derivative liabilities	12,165
Other liabilities	28,046
Total liabilities assumed	1,987,026
Total identifiable net assets	147,313
Consideration transferred
Cash	24,108
Common stock issued	$ 163,589
Common stock issued (in shares)	8,130,633
Total fair value of consideration transferred	$ 187,697
Goodwill	$ 40,384
FMBT
Assets
Cash and cash equivalents		$ 32,548
Loans and leases, net		192,494
Premises and equipment, net		8,524
BOLI		6,823
Net deferred tax asset		157
Core deposit intangible		2,800
Other assets		1,278
Total assets acquired		244,624
Liabilities
Deposits		212,127
Other liabilities		717
Total liabilities assumed		212,844
Total identifiable net assets		31,780
Consideration transferred
Cash		52,093
Goodwill		$ 20,313
Navitas
Assets
Cash and cash equivalents			$ 27,700
Loans and leases, net			358,352
Premises and equipment, net			324
Net deferred tax asset			2,873
Other assets			4,051
Total assets acquired			393,300
Liabilities
Short-term borrowings			214,923
Long-term debt			119,402
Other liabilities			16,108
Total liabilities assumed			350,433
Total identifiable net assets			42,867
Consideration transferred
Cash			84,500
Common stock issued			$ 45,746
Common stock issued (in shares)			1,443,987
Total fair value of consideration transferred			$ 130,246
Goodwill			$ 87,379

Mergers and Acquisitions - Ac_2

Mergers and Acquisitions - Acquired loan and lease portfolio at acquisition (Details) - USD ($) $ in Thousands	Jul. 01, 2020	May 01, 2019	Feb. 01, 2018
Three Shores
Non-PCD loans / Non-PCI loans:
Fair value	$ 1,164,675
Gross contractual amounts receivable	1,358,793
Estimate of contractual cash flows not expected to be collected	76,503
Three Shores | Purchase loans
PCD loans:
Par Value	283,137
ACL at acquisition	(11,152)
Non-credit discount	(8,694)
Purchase price	$ 263,291
FMBT
PCI loans:
Contractually required principal and interest		$ 13,145
Non-accretable difference		2,517
Cash flows expected to be collected		10,628
Accretable yield		1,300
Fair value		9,328
Non-PCD loans / Non-PCI loans:
Fair value		183,166
Gross contractual amounts receivable		218,855
Estimate of contractual cash flows not expected to be collected		$ 8,826
Navitas
PCI loans:
Contractually required principal and interest			$ 24,711
Non-accretable difference			5,505
Cash flows expected to be collected			19,206
Accretable yield			1,977
Fair value			17,229
Non-PCD loans / Non-PCI loans:
Fair value			341,123
Gross contractual amounts receivable			389,432
Estimate of contractual cash flows not expected to be collected			$ 8,624

Mergers and Acquisitions - Pro

Mergers and Acquisitions - Pro forma information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Supplemental consolidated pro forma revenue	$ 597,729	$ 636,079	$ 539,152
Supplemental consolidated pro forma net income (loss)	168,717	210,232	171,218
Three Shores
Business Acquisition [Line Items]
Actual revenue included since acquisition date	24,541
Actual net income included since acquisition date	$ 6,800
FMBT
Business Acquisition [Line Items]
Actual revenue included since acquisition date		7,525
Actual net income included since acquisition date		$ 4,053
Navitas
Business Acquisition [Line Items]
Actual revenue included since acquisition date			24,285
Actual net income included since acquisition date			$ 7,149

Cash Flows (Details)

Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flow [Line Items]
Transferred to foreclosed property	$ 822	$ 1,170	$ 3,020
Unsettled sales of government guaranteed loans	0	8,190	32,900
Assets acquired, fair value	2,170,000	265,000	481,000
Liabilities assumed, fair value	1,990,000	213,000	350,000
Net assets acquired	188,000	$ 52,100	130,000
Common stock issued for acquisitions	163,589		45,746
Common Stock
Cash Flow [Line Items]
Common stock issued for acquisitions	$ 164,000		$ 45,700

Investment Securities - Narrati

Investment Securities - Narrative (Details)	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2020USD ($)security
Investments, Debt and Equity Securities [Abstract]
Carrying value of securities pledged to secure public deposits, derivatives and other secured borrowings	$ 918,000,000		$ 1,110,000,000
Number of debt securities available for sale in unrealized loss position | security			72
Number of debt securities held-to-maturity in unrealized loss position | security			13
Other-than-temporary impairment charges	$ 0	$ 0
Allowance for credit losses, held-to-maturity portfolio			$ 0
Allowance for credit losses, available-for-sale portfolio			$ 0

Investment Securities - Cost ba

Investment Securities - Cost basis, unrealized gains and losses, and fair value of debt securities held to maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt securities held to maturity:
Amortized Cost	$ 420,361	$ 283,533
Gross Unrealized Gains	17,332	5,215
Gross Unrealized Losses	500	844
Fair Value	437,193	287,904
U.S. Government agencies & GSEs
Debt securities held to maturity:
Amortized Cost	10,575
Gross Unrealized Gains	26
Gross Unrealized Losses	11
Fair Value	10,590
State and political subdivisions
Debt securities held to maturity:
Amortized Cost	197,723	45,479
Gross Unrealized Gains	7,658	1,574
Gross Unrealized Losses	242	9
Fair Value	205,139	47,044
Residential mortgage-backed, Agency & GSE
Debt securities held to maturity:
Amortized Cost	113,400	153,967
Gross Unrealized Gains	4,774	2,014
Gross Unrealized Losses	1	694
Fair Value	118,173	155,287
Commercial mortgage-backed, Agency & GSE
Debt securities held to maturity:
Amortized Cost	98,663	84,087
Gross Unrealized Gains	4,874	1,627
Gross Unrealized Losses	246	141
Fair Value	$ 103,291	$ 85,573

Investment Securities - Cost _2

Investment Securities - Cost basis, unrealized gains and losses, and fair value of debt securities available for sale (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt securities available for sale:
Amortized Cost	$ 3,152,111	$ 2,240,607
Gross Unrealized Gains	75,108	36,982
Gross Unrealized Losses	2,498	3,008
Fair Value	3,224,721	2,274,581
U.S. Treasuries
Debt securities available for sale:
Amortized Cost	123,677	152,990
Gross Unrealized Gains	4,395	1,628
Gross Unrealized Losses	0	0
Fair Value	128,072	154,618
U.S. Government agencies & GSEs
Debt securities available for sale:
Amortized Cost	152,596	2,848
Gross Unrealized Gains	701	188
Gross Unrealized Losses	325	1
Fair Value	152,972	3,035
State and political subdivisions
Debt securities available for sale:
Amortized Cost	253,630	214,677
Gross Unrealized Gains	20,891	11,813
Gross Unrealized Losses	49	0
Fair Value	274,472	226,490
Residential mortgage-backed, Agency & GSE
Debt securities available for sale:
Amortized Cost	1,275,551	1,030,948
Gross Unrealized Gains	29,107	12,022
Gross Unrealized Losses	766	726
Fair Value	1,303,892	1,042,244
Residential mortgage-backed, Non-agency
Debt securities available for sale:
Amortized Cost	174,322	250,550
Gross Unrealized Gains	7,499	6,231
Gross Unrealized Losses	128	0
Fair Value	181,693	256,781
Commercial mortgage-backed, Agency & GSE
Debt securities available for sale:
Amortized Cost	524,852	266,770
Gross Unrealized Gains	8,013	2,261
Gross Unrealized Losses	597	128
Fair Value	532,268	268,903
Commercial mortgage-backed, Non-agency
Debt securities available for sale:
Amortized Cost	15,350	15,395
Gross Unrealized Gains	1,513	918
Gross Unrealized Losses	0	263
Fair Value	16,863	16,050
Corporate bonds
Debt securities available for sale:
Amortized Cost	70,057	202,131
Gross Unrealized Gains	1,711	1,178
Gross Unrealized Losses	1	218
Fair Value	71,767	203,091
Asset-backed securities
Debt securities available for sale:
Amortized Cost	562,076	104,298
Gross Unrealized Gains	1,278	743
Gross Unrealized Losses	632	1,672
Fair Value	$ 562,722	$ 103,369

Investment Securities - Summary

Investment Securities - Summary of held-to-maturity securities in unrealized loss position (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt securities held-to-maturity in an unrealized loss position
Fair Value, Less than 12 Months	$ 45,502	$ 48,007
Unrealized Loss, Less than 12 Months	490	160
Fair Value, 12 Months or More	1,352	49,922
Unrealized Loss, 12 Months or More	10	684
Fair Value, Total	46,854	97,929
Unrealized Loss, Total	500	844
U.S. Government agencies & GSEs
Debt securities held-to-maturity in an unrealized loss position
Fair Value, Less than 12 Months	4,677
Unrealized Loss, Less than 12 Months	11
Fair Value, 12 Months or More	0
Unrealized Loss, 12 Months or More	0
Fair Value, Total	4,677
Unrealized Loss, Total	11
State and political subdivisions
Debt securities held-to-maturity in an unrealized loss position
Fair Value, Less than 12 Months	14,870	10,117
Unrealized Loss, Less than 12 Months	242	9
Fair Value, 12 Months or More	0	0
Unrealized Loss, 12 Months or More	0	0
Fair Value, Total	14,870	10,117
Unrealized Loss, Total	242	9
Residential mortgage-backed, Agency & GSE
Debt securities held-to-maturity in an unrealized loss position
Fair Value, Less than 12 Months	999	16,049
Unrealized Loss, Less than 12 Months	1	64
Fair Value, 12 Months or More	0	48,237
Unrealized Loss, 12 Months or More	0	630
Fair Value, Total	999	64,286
Unrealized Loss, Total	1	694
Commercial mortgage-backed, Agency & GSE
Debt securities held-to-maturity in an unrealized loss position
Fair Value, Less than 12 Months	24,956	21,841
Unrealized Loss, Less than 12 Months	236	87
Fair Value, 12 Months or More	1,352	1,685
Unrealized Loss, 12 Months or More	10	54
Fair Value, Total	26,308	23,526
Unrealized Loss, Total	$ 246	$ 141

Investment Securities - Summa_2

Investment Securities - Summary of available-for-sale securities in unrealized loss position (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	$ 450,517	$ 281,051
Unrealized Loss, Less than 12 Months	1,893	1,418
Fair Value, 12 Months or More	54,194	96,663
Unrealized Loss, 12 Months or More	605	1,590
Fair Value, Total	504,711	377,714
Unrealized Loss, Total	2,498	3,008
U.S. Government agencies & GSEs
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	27,952	404
Unrealized Loss, Less than 12 Months	324	1
Fair Value, 12 Months or More	607	0
Unrealized Loss, 12 Months or More	1	0
Fair Value, Total	28,559	404
Unrealized Loss, Total	325	1
State and political subdivisions
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	9,402
Unrealized Loss, Less than 12 Months	49
Fair Value, 12 Months or More	0
Unrealized Loss, 12 Months or More	0
Fair Value, Total	9,402
Unrealized Loss, Total	49
Residential mortgage-backed, Agency & GSE
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	232,199	228,611
Unrealized Loss, Less than 12 Months	766	576
Fair Value, 12 Months or More	0	18,294
Unrealized Loss, 12 Months or More	0	150
Fair Value, Total	232,199	246,905
Unrealized Loss, Total	766	726
Residential mortgage-backed, Non-agency
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	2,331
Unrealized Loss, Less than 12 Months	128
Fair Value, 12 Months or More	0
Unrealized Loss, 12 Months or More	0
Fair Value, Total	2,331
Unrealized Loss, Total	128
Commercial mortgage-backed, Agency & GSE
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	89,918	0
Unrealized Loss, Less than 12 Months	597	0
Fair Value, 12 Months or More	0	33,517
Unrealized Loss, 12 Months or More	0	128
Fair Value, Total	89,918	33,517
Unrealized Loss, Total	597	128
Commercial mortgage-backed, Non-agency
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months		0
Unrealized Loss, Less than 12 Months		0
Fair Value, 12 Months or More		4,864
Unrealized Loss, 12 Months or More		263
Fair Value, Total		4,864
Unrealized Loss, Total		263
Corporate bonds
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	1,410	19,742
Unrealized Loss, Less than 12 Months	1	216
Fair Value, 12 Months or More	0	998
Unrealized Loss, 12 Months or More	0	2
Fair Value, Total	1,410	20,740
Unrealized Loss, Total	1	218
Asset-backed securities
Debt securities available-for-sale in an unrealized loss position
Fair Value, Less than 12 Months	87,305	32,294
Unrealized Loss, Less than 12 Months	28	625
Fair Value, 12 Months or More	53,587	38,990
Unrealized Loss, 12 Months or More	604	1,047
Fair Value, Total	140,892	71,284
Unrealized Loss, Total	$ 632	$ 1,672

Investment Securities - Summa_3

Investment Securities - Summary of securities sales activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales	$ 40,625	$ 352,106	$ 168,891
Gross gains on sales	748	1,843	2,082
Gross losses on sales	0	(2,864)	(2,738)
Net gains (losses) on sales of securities	748	(1,021)	(656)
Income tax expense (benefit) attributable to sales	$ 191	$ (247)	$ (132)

Investment Securities - Amortiz

Investment Securities - Amortized cost and fair value of held-to-maturity and available-for-sale securities by contractual maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Within 1 year	$ 51,676
Available-for-Sale, Amortized Cost, 1 to 5 years	213,363
Available-for-Sale, Amortized Cost, 5 to 10 years	128,631
Available-for-Sale, Amortized Cost, More than 10 years	206,290
Amortized Cost	3,152,111	$ 2,240,607
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Within 1 year	52,336
Available-for-Sale, Fair Value, 1 to 5 years	221,962
Available-for-Sale, Fair Value, 5 to 10 years	133,809
Available-for-Sale, Fair Value, More than 10 years	219,176
Fair Value	3,224,721	2,274,581
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Within 1 year	1,700
Held-to-Maturity, Amortized Cost, 1 to 5 years	14,505
Held-to-Maturity, Amortized Cost, 5 to 10 years	7,028
Held-to-Maturity, Amortized Cost, More than 10 years	185,065
Amortized Cost	420,361	283,533
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Within 1 year	1,743
Held-to-Maturity, Fair Value, 1 to 5 years	16,059
Held-to-Maturity, Fair Value, 5 to 10 years	7,957
Held-to-Maturity, Fair Value, More than 10 years	189,970
Fair value	437,193	287,904
U.S. Treasuries
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Within 1 year	20,014
Available-for-Sale, Amortized Cost, 1 to 5 years	103,663
Amortized Cost	123,677	152,990
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Within 1 year	20,311
Available-for-Sale, Fair Value, 1 to 5 years	107,761
Fair Value	128,072	154,618
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Within 1 year	0
Held-to-Maturity, Amortized Cost, 1 to 5 years	0
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Within 1 year	0
Held-to-Maturity, Fair Value, 1 to 5 years	0
U.S. Government agencies & GSEs
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Within 1 year	201
Available-for-Sale, Amortized Cost, 1 to 5 years	16,710
Available-for-Sale, Amortized Cost, 5 to 10 years	55,588
Available-for-Sale, Amortized Cost, More than 10 years	80,097
Amortized Cost	152,596	2,848
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Within 1 year	201
Available-for-Sale, Fair Value, 1 to 5 years	16,820
Available-for-Sale, Fair Value, 5 to 10 years	55,481
Available-for-Sale, Fair Value, More than 10 years	80,470
Fair Value	152,972	3,035
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Within 1 year	0
Held-to-Maturity, Amortized Cost, 1 to 5 years	0
Held-to-Maturity, Amortized Cost, 5 to 10 years	0
Held-to-Maturity, Amortized Cost, More than 10 years	10,575
Amortized Cost	10,575
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Within 1 year	0
Held-to-Maturity, Fair Value, 1 to 5 years	0
Held-to-Maturity, Fair Value, 5 to 10 years	0
Held-to-Maturity, Fair Value, More than 10 years	10,590
Fair value	10,590
State and political subdivisions
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Within 1 year	20,020
Available-for-Sale, Amortized Cost, 1 to 5 years	48,354
Available-for-Sale, Amortized Cost, 5 to 10 years	59,837
Available-for-Sale, Amortized Cost, More than 10 years	125,419
Amortized Cost	253,630	214,677
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Within 1 year	20,232
Available-for-Sale, Fair Value, 1 to 5 years	51,544
Available-for-Sale, Fair Value, 5 to 10 years	64,843
Available-for-Sale, Fair Value, More than 10 years	137,853
Fair Value	274,472	226,490
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Within 1 year	1,700
Held-to-Maturity, Amortized Cost, 1 to 5 years	14,505
Held-to-Maturity, Amortized Cost, 5 to 10 years	7,028
Held-to-Maturity, Amortized Cost, More than 10 years	174,490
Amortized Cost	197,723	45,479
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Within 1 year	1,743
Held-to-Maturity, Fair Value, 1 to 5 years	16,059
Held-to-Maturity, Fair Value, 5 to 10 years	7,957
Held-to-Maturity, Fair Value, More than 10 years	179,380
Fair value	205,139	47,044
Corporate bonds
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Within 1 year	11,441
Available-for-Sale, Amortized Cost, 1 to 5 years	44,636
Available-for-Sale, Amortized Cost, 5 to 10 years	13,206
Available-for-Sale, Amortized Cost, More than 10 years	774
Amortized Cost	70,057	202,131
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Within 1 year	11,592
Available-for-Sale, Fair Value, 1 to 5 years	45,837
Available-for-Sale, Fair Value, 5 to 10 years	13,485
Available-for-Sale, Fair Value, More than 10 years	853
Fair Value	71,767	203,091
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Within 1 year	0
Held-to-Maturity, Amortized Cost, 1 to 5 years	0
Held-to-Maturity, Amortized Cost, 5 to 10 years	0
Held-to-Maturity, Amortized Cost, More than 10 years	0
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Within 1 year	0
Held-to-Maturity, Fair Value, 1 to 5 years	0
Held-to-Maturity, Fair Value, 5 to 10 years	0
Held-to-Maturity, Fair Value, More than 10 years	0
Asset-backed securities
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Not due at single maturity	562,076
Amortized Cost	562,076	104,298
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Not due at single maturity	562,722
Fair Value	562,722	$ 103,369
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Not due at single maturity	0
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Not due at single maturity	0
Residential mortgage-backed securities
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Not due at single maturity	1,449,873
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Not due at single maturity	1,485,585
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Not due at single maturity	113,400
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Not due at single maturity	118,173
Commercial mortgage-backed securities
Available-for-Sale, Amortized Cost
Available-for-Sale, Amortized Cost, Not due at single maturity	540,202
Available-for-Sale, Fair Value
Available-for-Sale, Fair Value, Not due at single maturity	549,131
Held-to-Maturity, Amortized Cost
Held-to-Maturity, Amortized Cost, Not due at single maturity	98,663
Held-to-Maturity, Fair Value
Held-to-Maturity, Fair Value, Not due at single maturity	$ 103,291

Loans and Leases and Allowanc_3

Loans and Leases and Allowance for Credit Losses - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net investment in leases	$ 36,802	$ 37,378
Gross additional interest income that would have been earned if the nonaccrual loans had performed as per original term	2,860	1,260	$ 1,090
Carrying value of PCI loans		58,646
TDRs	61,600	54,200
Loans receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Short-term deferrals related to COVID-19 crisis	70,700
Carrying value of PCI loans		58,646
Outstanding balance of PCI loans		83,100
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Overdrawn deposit accounts	$ 2,180	1,300
Consumer | Loans receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value of PCI loans		$ 336

Loans and Leases and Allowanc_4

Loans and Leases and Allowance for Credit Losses - Major classifications of the loan and lease portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Classifications of loans
Total loans	$ 11,370,815	$ 8,812,553
Less ACL - loans	(137,010)	(62,089)	$ (61,203)	$ (58,914)
Loans and leases, net	11,233,805	8,750,464
Loans receivable
Classifications of loans
Total loans	11,370,815	8,812,553
Loans receivable | Commercial
Classifications of loans
Total loans	8,960,888	6,669,593
Loans receivable | Commercial | Owner occupied commercial real estate
Classifications of loans
Total loans	2,090,443	1,720,227
Less ACL - loans	(20,673)	(11,404)	(12,207)	(14,776)
Loans receivable | Commercial | Income producing commercial real estate
Classifications of loans
Total loans	2,540,750	2,007,950
Less ACL - loans	(41,737)	(12,306)	(11,073)	(9,381)
Loans receivable | Commercial | Commercial & industrial
Classifications of loans
Total loans	2,498,560	1,220,657
Less ACL - loans	(22,019)	(5,266)	(4,802)	(3,971)
Loans receivable | Commercial | PPP loans included in commercial & industrial
Classifications of loans
Total loans	646,000
Loans receivable | Commercial | Construction
Classifications of loans
Total loans	967,305	976,215
Less ACL - loans	(10,952)	(9,668)	(10,337)	(10,523)
Loans receivable | Commercial | Equipment financing
Classifications of loans
Total loans	863,830	744,544
Less ACL - loans	(16,820)	(7,384)	(5,452)	0
Loans receivable | Residential | Residential mortgage
Classifications of loans
Total loans	1,284,920	1,117,616
Less ACL - loans	(15,341)	(8,081)	(8,295)	(10,097)
Loans receivable | Residential | Home equity lines of credit
Classifications of loans
Total loans	697,117	660,675
Less ACL - loans	(8,417)	(4,575)	(4,752)	(5,177)
Loans receivable | Residential | Construction
Classifications of loans
Total loans	281,430	236,437
Less ACL - loans	(764)	(2,504)	(2,433)	(2,729)
Loans receivable | Consumer
Classifications of loans
Total loans	146,460	128,232
Less ACL - loans	$ (287)	$ (901)	$ (853)	$ (710)

Loans and Leases and Allowanc_5

Loans and Leases and Allowance for Credit Losses - Loans Sold (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans sold	$ 75,403	$ 214,899	$ 120,977
Guaranteed portion of SBA/USDA loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans sold	48,385	81,158	120,977
Equipment financing
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans sold	27,018	30,952	0
Indirect auto
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans sold	$ 0	$ 102,789	$ 0

Loans and Leases and Allowanc_6

Loans and Leases and Allowance for Credit Losses - Components of net investment in leases (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Minimum future lease payments receivable	$ 38,934	$ 39,709
Estimated residual value of leased equipment	3,263	3,631
Initial direct costs	672	842
Security deposits	(727)	(989)
Purchase accounting premium	117	273
Unearned income	(5,457)	(6,088)
Net investment in leases	$ 36,802	$ 37,378

Loans and Leases and Allowanc_7

Loans and Leases and Allowance for Credit Losses - Minimum future lease payments to be received (Details) $ in Thousands	Dec. 31, 2020USD ($)
Minimum future lease payments expected to be received
2021	$ 15,152
2022	11,516
2023	7,452
2024	3,429
2025	1,341
Thereafter	44
Total	$ 38,934

Loans and Leases and Allowanc_8

Loans and Leases and Allowance for Credit Losses - Aging of amortized cost basis in loans by aging category and accrual status (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans by aging category
Total loans	$ 11,370,815	$ 8,812,553
Loans receivable
Loans by aging category
Total loans	11,370,815	8,812,553
Nonaccrual Loans	61,599	35,341
Loans receivable | Current Loans
Loans by aging category
Total loans	11,288,847	8,712,667
Loans receivable | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	15,744
Loans receivable | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	4,625
Loans receivable | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial
Loans by aging category
Total loans	8,960,888	6,669,593
Nonaccrual Loans	45,515	20,503
Loans receivable | Commercial | Current Loans
Loans by aging category
Total loans	8,905,003	6,596,675
Loans receivable | Commercial | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	7,459
Loans receivable | Commercial | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	2,911
Loans receivable | Commercial | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial | Owner occupied commercial real estate
Loans by aging category
Total loans	2,090,443	1,720,227
Nonaccrual Loans	8,582	10,544
Loans receivable | Commercial | Owner occupied commercial real estate | Current Loans
Loans by aging category
Total loans	2,079,845	1,700,682
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	2,013
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	3
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial | Income producing commercial real estate
Loans by aging category
Total loans	2,540,750	2,007,950
Nonaccrual Loans	15,149	1,996
Loans receivable | Commercial | Income producing commercial real estate | Current Loans
Loans by aging category
Total loans	2,522,743	1,979,053
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	1,608
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	1,250
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial | Commercial & industrial
Loans by aging category
Total loans	2,498,560	1,220,657
Nonaccrual Loans	16,634	2,545
Loans receivable | Commercial | Commercial & industrial | Current Loans
Loans by aging category
Total loans	2,480,483	1,215,581
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	1,176
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	267
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial | Construction
Loans by aging category
Total loans	967,305	976,215
Nonaccrual Loans	1,745	2,277
Loans receivable | Commercial | Construction | Current Loans
Loans by aging category
Total loans	964,947	966,833
Loans receivable | Commercial | Construction | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	231
Loans receivable | Commercial | Construction | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	382
Loans receivable | Commercial | Construction | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Commercial | Equipment financing
Loans by aging category
Total loans	863,830	744,544
Nonaccrual Loans	3,405	3,141
Loans receivable | Commercial | Equipment financing | Current Loans
Loans by aging category
Total loans	856,985	734,526
Loans receivable | Commercial | Equipment financing | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	2,431
Loans receivable | Commercial | Equipment financing | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	1,009
Loans receivable | Commercial | Equipment financing | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Residential | Construction
Loans by aging category
Total loans	281,430	236,437
Nonaccrual Loans	514	939
Loans receivable | Residential | Construction | Current Loans
Loans by aging category
Total loans	280,551	235,211
Loans receivable | Residential | Construction | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	365
Loans receivable | Residential | Construction | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	0
Loans receivable | Residential | Construction | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Residential | Residential mortgage
Loans by aging category
Total loans	1,284,920	1,117,616
Nonaccrual Loans	12,858	10,567
Loans receivable | Residential | Residential mortgage | Current Loans
Loans by aging category
Total loans	1,265,019	1,097,999
Loans receivable | Residential | Residential mortgage | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	5,549
Loans receivable | Residential | Residential mortgage | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	1,494
Loans receivable | Residential | Residential mortgage | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Residential | Home equity lines of credit
Loans by aging category
Total loans	697,117	660,675
Nonaccrual Loans	2,487	3,173
Loans receivable | Residential | Home equity lines of credit | Current Loans
Loans by aging category
Total loans	692,504	655,762
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	1,942
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	184
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	0
Loans receivable | Consumer
Loans by aging category
Total loans	146,460	128,232
Nonaccrual Loans	225	159
Loans receivable | Consumer | Current Loans
Loans by aging category
Total loans	145,770	$ 127,020
Loans receivable | Consumer | Loans Past Due, 30 - 59 Days
Loans by aging category
Total loans	429
Loans receivable | Consumer | Loans Past Due, 60 - 89 Days
Loans by aging category
Total loans	36
Loans receivable | Consumer | Loans Past Due, > 90 Days
Loans by aging category
Loans Past Due	$ 0

Loans and Leases and Allowanc_9

Loans and Leases and Allowance for Credit Losses - Aging of recorded investment in loans, including accruing and nonaccrual loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
PCI Loans		$ 58,646
Total loans	$ 11,370,815	8,812,553
Loans receivable
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		41,240
PCI Loans		58,646
Total loans	11,370,815	8,812,553
Loans receivable | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		17,892
Total loans	15,744
Loans receivable | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		7,623
Total loans	4,625
Loans receivable | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		15,725
Loans receivable | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	11,288,847	8,712,667
Loans receivable | Commercial
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		25,971
PCI Loans		46,947
Total loans	8,960,888	6,669,593
Loans receivable | Commercial | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		9,547
Total loans	7,459
Loans receivable | Commercial | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		4,684
Total loans	2,911
Loans receivable | Commercial | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		11,740
Loans receivable | Commercial | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	8,905,003	6,596,675
Loans receivable | Commercial | Owner occupied commercial real estate
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		10,999
PCI Loans		8,546
Total loans	2,090,443	1,720,227
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,913
Total loans	2,013
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,007
Total loans	3
Loans receivable | Commercial | Owner occupied commercial real estate | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		6,079
Loans receivable | Commercial | Owner occupied commercial real estate | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	2,079,845	1,700,682
Loans receivable | Commercial | Income producing commercial real estate
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		1,669
PCI Loans		27,228
Total loans	2,540,750	2,007,950
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		562
Total loans	1,608
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		706
Total loans	1,250
Loans receivable | Commercial | Income producing commercial real estate | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		401
Loans receivable | Commercial | Income producing commercial real estate | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	2,522,743	1,979,053
Loans receivable | Commercial | Commercial & industrial
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		4,750
PCI Loans		326
Total loans	2,498,560	1,220,657
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,140
Total loans	1,176
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		491
Total loans	267
Loans receivable | Commercial | Commercial & industrial | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,119
Loans receivable | Commercial | Commercial & industrial | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	2,480,483	1,215,581
Loans receivable | Commercial | Construction
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,520
PCI Loans		6,862
Total loans	967,305	976,215
Loans receivable | Commercial | Construction | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		1,867
Total loans	231
Loans receivable | Commercial | Construction | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		557
Total loans	382
Loans receivable | Commercial | Construction | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		96
Loans receivable | Commercial | Construction | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	964,947	966,833
Loans receivable | Commercial | Equipment financing
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		6,033
PCI Loans		3,985
Total loans	863,830	744,544
Loans receivable | Commercial | Equipment financing | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,065
Total loans	2,431
Loans receivable | Commercial | Equipment financing | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		923
Total loans	1,009
Loans receivable | Commercial | Equipment financing | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		3,045
Loans receivable | Commercial | Equipment financing | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	856,985	734,526
Loans receivable | Residential | Construction
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		852
PCI Loans		374
Total loans	281,430	236,437
Loans receivable | Residential | Construction | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		325
Total loans	365
Loans receivable | Residential | Construction | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		125
Total loans	0
Loans receivable | Residential | Construction | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		402
Loans receivable | Residential | Construction | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	280,551	235,211
Loans receivable | Residential | Residential mortgage
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		10,038
PCI Loans		9,579
Total loans	1,284,920	1,117,616
Loans receivable | Residential | Residential mortgage | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		5,655
Total loans	5,549
Loans receivable | Residential | Residential mortgage | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,212
Total loans	1,494
Loans receivable | Residential | Residential mortgage | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		2,171
Loans receivable | Residential | Residential mortgage | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	1,265,019	1,097,999
Loans receivable | Residential | Home equity lines of credit
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		3,503
PCI Loans		1,410
Total loans	697,117	660,675
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		1,697
Total loans	1,942
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		421
Total loans	184
Loans receivable | Residential | Home equity lines of credit | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		1,385
Loans receivable | Residential | Home equity lines of credit | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	692,504	655,762
Loans receivable | Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		876
PCI Loans		336
Total loans	146,460	128,232
Loans receivable | Consumer | Loans Past Due, 30 - 59 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		668
Total loans	429
Loans receivable | Consumer | Loans Past Due, 60 - 89 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		181
Total loans	36
Loans receivable | Consumer | Loans Past Due, > 90 Days
Financing Receivable, Past Due [Line Items]
Loans Past Due - Accruing And Nonaccrual		27
Loans receivable | Consumer | Current Loans
Financing Receivable, Past Due [Line Items]
Total loans	$ 145,770	$ 127,020

Loans and Leases and Allowan_10

Loans and Leases and Allowance for Credit Losses - Recorded investment in nonaccrual loans by loan class (Details) - Loans receivable - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans by aging category
Nonaccrual loans with no allowance	$ 23,760
Nonaccrual loans with an allowance	37,839
Nonaccrual Loans	61,599	$ 35,341
Commercial
Loans by aging category
Nonaccrual loans with no allowance	20,121
Nonaccrual loans with an allowance	25,394
Nonaccrual Loans	45,515	20,503
Commercial | Owner occupied commercial real estate
Loans by aging category
Nonaccrual loans with no allowance	6,614
Nonaccrual loans with an allowance	1,968
Nonaccrual Loans	8,582	10,544
Commercial | Income producing commercial real estate
Loans by aging category
Nonaccrual loans with no allowance	10,008
Nonaccrual loans with an allowance	5,141
Nonaccrual Loans	15,149	1,996
Commercial | Commercial & industrial
Loans by aging category
Nonaccrual loans with no allowance	2,004
Nonaccrual loans with an allowance	14,630
Nonaccrual Loans	16,634	2,545
Commercial | Construction
Loans by aging category
Nonaccrual loans with no allowance	1,339
Nonaccrual loans with an allowance	406
Nonaccrual Loans	1,745	2,277
Commercial | Equipment financing
Loans by aging category
Nonaccrual loans with no allowance	156
Nonaccrual loans with an allowance	3,249
Nonaccrual Loans	3,405	3,141
Residential | Construction
Loans by aging category
Nonaccrual loans with no allowance	274
Nonaccrual loans with an allowance	240
Nonaccrual Loans	514	939
Residential | Residential mortgage
Loans by aging category
Nonaccrual loans with no allowance	1,855
Nonaccrual loans with an allowance	11,003
Nonaccrual Loans	12,858	10,567
Residential | Home equity lines of credit
Loans by aging category
Nonaccrual loans with no allowance	1,329
Nonaccrual loans with an allowance	1,158
Nonaccrual Loans	2,487	3,173
Consumer
Loans by aging category
Nonaccrual loans with no allowance	181
Nonaccrual loans with an allowance	44
Nonaccrual Loans	$ 225	$ 159

Loans and Leases and Allowan_11

Loans and Leases and Allowance for Credit Losses - Amortized cost of loans by risk category by vintage year (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 4,219,098
2019	1,865,899
2018	1,433,719
2017	874,745
2016	759,094
Prior	789,304
Revolvers	1,368,554
Revolvers converted to term loans	60,402
Total	11,370,815	$ 8,812,553
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	4,093,543
2019	1,773,077
2018	1,352,195
2017	815,046
2016	669,394
Prior	753,530
Revolvers	1,338,027
Revolvers converted to term loans	52,038
Total	10,846,850	8,558,459
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	67,047
2019	63,506
2018	47,167
2017	47,185
2016	47,536
Prior	16,559
Revolvers	6,564
Revolvers converted to term loans	1,681
Total	297,245	93,703
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	58,508
2019	29,316
2018	34,357
2017	12,514
2016	42,164
Prior	19,215
Revolvers	23,963
Revolvers converted to term loans	6,683
Total	226,720	$ 160,391
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	3,343,874
2019	1,521,690
2018	1,208,471
2017	685,027
2016	540,614
Prior	508,536
Revolvers	620,686
Revolvers converted to term loans	28,924
Total	8,457,822
Commercial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	67,047
2019	63,506
2018	47,167
2017	47,185
2016	47,536
Prior	16,559
Revolvers	6,564
Revolvers converted to term loans	1,681
Total	297,245
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	56,353
2019	27,076
2018	31,080
2017	11,081
2016	41,283
Prior	12,877
Revolvers	23,698
Revolvers converted to term loans	2,373
Total	205,821
Commercial | Owner occupied commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	707,501
2019	368,615
2018	231,316
2017	197,778
2016	201,362
Prior	229,667
Revolvers	56,273
Revolvers converted to term loans	9,072
Total	2,001,584
Commercial | Owner occupied commercial real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	8,759
2019	4,088
2018	4,221
2017	10,025
2016	11,138
Prior	4,728
Revolvers	100
Revolvers converted to term loans	0
Total	43,059
Commercial | Owner occupied commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	6,586
2019	10,473
2018	7,596
2017	3,717
2016	6,753
Prior	8,473
Revolvers	1,528
Revolvers converted to term loans	674
Total	45,800
Commercial | Income producing commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	815,799
2019	376,911
2018	361,539
2017	277,769
2016	206,068
Prior	198,080
Revolvers	28,542
Revolvers converted to term loans	12,128
Total	2,276,836
Commercial | Income producing commercial real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	35,471
2019	42,831
2018	39,954
2017	13,238
2016	24,164
Prior	11,337
Revolvers	0
Revolvers converted to term loans	1,681
Total	168,676
Commercial | Income producing commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	45,125
2019	8,940
2018	2,179
2017	5,034
2016	31,211
Prior	2,652
Revolvers	0
Revolvers converted to term loans	97
Total	95,238
Commercial | Commercial & industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,092,767
2019	287,857
2018	263,439
2017	115,790
2016	92,968
Prior	58,359
Revolvers	515,593
Revolvers converted to term loans	3,777
Total	2,430,550
Commercial | Commercial & industrial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,451
2019	16,315
2018	2,176
2017	630
2016	459
Prior	17
Revolvers	6,464
Revolvers converted to term loans	0
Total	27,512
Commercial | Commercial & industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	1,545
2019	5,536
2018	6,193
2017	1,684
2016	1,292
Prior	1,485
Revolvers	22,170
Revolvers converted to term loans	593
Total	40,498
Commercial | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	314,154
2019	217,643
2018	226,308
2017	53,708
2016	30,812
Prior	21,985
Revolvers	20,278
Revolvers converted to term loans	3,947
Total	888,835
Commercial | Construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	21,366
2019	272
2018	816
2017	23,292
2016	11,775
Prior	477
Revolvers	0
Revolvers converted to term loans	0
Total	57,998
Commercial | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,466
2019	735
2018	13,741
2017	340
2016	1,931
Prior	250
Revolvers	0
Revolvers converted to term loans	1,009
Total	20,472
Commercial | Equipment financing | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	413,653
2019	270,664
2018	125,869
2017	39,982
2016	9,404
Prior	445
Revolvers	0
Revolvers converted to term loans	0
Total	860,017
Commercial | Equipment financing | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	0
Revolvers converted to term loans	0
Total	0
Commercial | Equipment financing | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	631
2019	1,392
2018	1,371
2017	306
2016	96
Prior	17
Revolvers	0
Revolvers converted to term loans	0
Total	3,813
Residential | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	225,727
2019	30,646
2018	4,026
2017	4,544
2016	3,172
Prior	12,546
Revolvers	0
Revolvers converted to term loans	64
Total	280,725
Residential | Construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	0
Revolvers converted to term loans	0
Total	0
Residential | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	106
2019	37
2018	54
2017	4
2016	124
Prior	380
Revolvers	0
Revolvers converted to term loans	0
Total	705
Residential | Residential mortgage | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	468,945
2019	195,213
2018	125,492
2017	120,944
2016	122,013
Prior	230,771
Revolvers	18
Revolvers converted to term loans	5,393
Total	1,268,789
Residential | Residential mortgage | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	0
Revolvers converted to term loans	0
Total	0
Residential | Residential mortgage | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,049
2019	2,106
2018	3,174
2017	1,369
2016	679
Prior	5,860
Revolvers	0
Revolvers converted to term loans	894
Total	16,131
Residential | Home equity lines of credit | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	675,878
Revolvers converted to term loans	17,581
Total	693,459
Residential | Home equity lines of credit | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	0
Revolvers converted to term loans	0
Total	0
Residential | Home equity lines of credit | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	265
Revolvers converted to term loans	3,393
Total	3,658
Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	54,997
2019	25,528
2018	14,206
2017	4,531
2016	3,595
Prior	1,677
Revolvers	41,445
Revolvers converted to term loans	76
Total	146,055
Consumer | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolvers	0
Revolvers converted to term loans	0
Total	0
Consumer | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	97
2018	49
2017	60
2016	78
Prior	98
Revolvers	0
Revolvers converted to term loans	23
Total	$ 405

Loans and Leases and Allowan_12

Loans and Leases and Allowance for Credit Losses - Risk category of loans by class of loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Risk category of loans by class of loans
PCI Loans		$ 58,646
Total loans	$ 11,370,815	8,812,553
Pass
Risk category of loans by class of loans
Total loans	10,846,850	8,558,459
Watch
Risk category of loans by class of loans
Total loans	297,245	93,703
Substandard
Risk category of loans by class of loans
Total loans	226,720	160,391
Doubtful / Loss
Risk category of loans by class of loans
Total loans		0
Commercial | Pass
Risk category of loans by class of loans
Total loans	8,457,822
Commercial | Watch
Risk category of loans by class of loans
Total loans	297,245
Commercial | Substandard
Risk category of loans by class of loans
Total loans	205,821
Commercial | Owner occupied commercial real estate | Pass
Risk category of loans by class of loans
Total loans	2,001,584
Commercial | Owner occupied commercial real estate | Watch
Risk category of loans by class of loans
Total loans	43,059
Commercial | Owner occupied commercial real estate | Substandard
Risk category of loans by class of loans
Total loans	45,800
Commercial | Income producing commercial real estate | Pass
Risk category of loans by class of loans
Total loans	2,276,836
Commercial | Income producing commercial real estate | Watch
Risk category of loans by class of loans
Total loans	168,676
Commercial | Income producing commercial real estate | Substandard
Risk category of loans by class of loans
Total loans	95,238
Commercial | Commercial & industrial | Pass
Risk category of loans by class of loans
Total loans	2,430,550
Commercial | Commercial & industrial | Watch
Risk category of loans by class of loans
Total loans	27,512
Commercial | Commercial & industrial | Substandard
Risk category of loans by class of loans
Total loans	40,498
Commercial | Construction | Pass
Risk category of loans by class of loans
Total loans	888,835
Commercial | Construction | Watch
Risk category of loans by class of loans
Total loans	57,998
Commercial | Construction | Substandard
Risk category of loans by class of loans
Total loans	20,472
Commercial | Equipment financing | Pass
Risk category of loans by class of loans
Total loans	860,017
Commercial | Equipment financing | Watch
Risk category of loans by class of loans
Total loans	0
Commercial | Equipment financing | Substandard
Risk category of loans by class of loans
Total loans	3,813
Residential | Construction | Pass
Risk category of loans by class of loans
Total loans	280,725
Residential | Construction | Watch
Risk category of loans by class of loans
Total loans	0
Residential | Construction | Substandard
Risk category of loans by class of loans
Total loans	705
Residential | Residential mortgage | Pass
Risk category of loans by class of loans
Total loans	1,268,789
Residential | Residential mortgage | Watch
Risk category of loans by class of loans
Total loans	0
Residential | Residential mortgage | Substandard
Risk category of loans by class of loans
Total loans	16,131
Residential | Home equity lines of credit | Pass
Risk category of loans by class of loans
Total loans	693,459
Residential | Home equity lines of credit | Watch
Risk category of loans by class of loans
Total loans	0
Residential | Home equity lines of credit | Substandard
Risk category of loans by class of loans
Total loans	3,658
Consumer | Pass
Risk category of loans by class of loans
Total loans	146,055
Consumer | Watch
Risk category of loans by class of loans
Total loans	0
Consumer | Substandard
Risk category of loans by class of loans
Total loans	405
Loans receivable
Risk category of loans by class of loans
Total loans, excluding PCI loans		8,753,907
PCI Loans		58,646
Total loans	11,370,815	8,812,553
Loans receivable | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		8,517,776
PCI Loans		40,683
Loans receivable | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		83,930
PCI Loans		9,773
Loans receivable | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		152,201
PCI Loans		8,190
Loans receivable | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial
Risk category of loans by class of loans
Total loans, excluding PCI loans		6,622,646
PCI Loans		46,947
Total loans	8,960,888	6,669,593
Loans receivable | Commercial | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		6,406,957
PCI Loans		30,570
Loans receivable | Commercial | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		83,922
PCI Loans		9,773
Loans receivable | Commercial | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		131,767
PCI Loans		6,604
Loans receivable | Commercial | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Owner occupied commercial real estate
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,711,681
PCI Loans		8,546
Total loans	2,090,443	1,720,227
Loans receivable | Commercial | Owner occupied commercial real estate | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,638,398
PCI Loans		3,238
Loans receivable | Commercial | Owner occupied commercial real estate | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		24,563
PCI Loans		2,797
Loans receivable | Commercial | Owner occupied commercial real estate | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		48,720
PCI Loans		2,511
Loans receivable | Commercial | Owner occupied commercial real estate | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Income producing commercial real estate
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,980,722
PCI Loans		27,228
Total loans	2,540,750	2,007,950
Loans receivable | Commercial | Income producing commercial real estate | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,914,524
PCI Loans		19,648
Loans receivable | Commercial | Income producing commercial real estate | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		40,676
PCI Loans		6,305
Loans receivable | Commercial | Income producing commercial real estate | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		25,522
PCI Loans		1,275
Loans receivable | Commercial | Income producing commercial real estate | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Commercial & industrial
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,220,331
PCI Loans		326
Total loans	2,498,560	1,220,657
Loans receivable | Commercial | Commercial & industrial | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,156,366
PCI Loans		104
Loans receivable | Commercial | Commercial & industrial | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		16,385
PCI Loans		81
Loans receivable | Commercial | Commercial & industrial | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		47,580
PCI Loans		141
Loans receivable | Commercial | Commercial & industrial | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Construction
Risk category of loans by class of loans
Total loans, excluding PCI loans		969,353
PCI Loans		6,862
Total loans	967,305	976,215
Loans receivable | Commercial | Construction | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		960,251
PCI Loans		3,628
Loans receivable | Commercial | Construction | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		2,298
PCI Loans		590
Loans receivable | Commercial | Construction | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		6,804
PCI Loans		2,644
Loans receivable | Commercial | Construction | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Equipment financing
Risk category of loans by class of loans
Total loans, excluding PCI loans		740,559
PCI Loans		3,985
Total loans	863,830	744,544
Loans receivable | Commercial | Equipment financing | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		737,418
PCI Loans		3,952
Loans receivable | Commercial | Equipment financing | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Commercial | Equipment financing | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		3,141
PCI Loans		33
Loans receivable | Commercial | Equipment financing | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Construction
Risk category of loans by class of loans
Total loans, excluding PCI loans		236,063
PCI Loans		374
Total loans	281,430	236,437
Loans receivable | Residential | Construction | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		234,791
PCI Loans		348
Loans receivable | Residential | Construction | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Construction | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,272
PCI Loans		26
Loans receivable | Residential | Construction | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Residential mortgage
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,108,037
PCI Loans		9,579
Total loans	1,284,920	1,117,616
Loans receivable | Residential | Residential mortgage | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		1,093,902
PCI Loans		8,112
Loans receivable | Residential | Residential mortgage | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Residential mortgage | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		14,135
PCI Loans		1,467
Loans receivable | Residential | Residential mortgage | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Home equity lines of credit
Risk category of loans by class of loans
Total loans, excluding PCI loans		659,265
PCI Loans		1,410
Total loans	697,117	660,675
Loans receivable | Residential | Home equity lines of credit | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		654,619
PCI Loans		1,350
Loans receivable | Residential | Home equity lines of credit | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Residential | Home equity lines of credit | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		4,646
PCI Loans		60
Loans receivable | Residential | Home equity lines of credit | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		0
Loans receivable | Consumer
Risk category of loans by class of loans
Total loans, excluding PCI loans		127,896
PCI Loans		336
Total loans	$ 146,460	128,232
Loans receivable | Consumer | Pass
Risk category of loans by class of loans
Total loans, excluding PCI loans		127,507
PCI Loans		303
Loans receivable | Consumer | Watch
Risk category of loans by class of loans
Total loans, excluding PCI loans		8
PCI Loans		0
Loans receivable | Consumer | Substandard
Risk category of loans by class of loans
Total loans, excluding PCI loans		381
PCI Loans		33
Loans receivable | Consumer | Doubtful / Loss
Risk category of loans by class of loans
Total loans, excluding PCI loans		0
PCI Loans		$ 0

Loans and Leases and Allowan_13

Loans and Leases and Allowance for Credit Losses - Changes in the value of the accretable yield for PCI loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Changes in balance of accretable yield for PCI loans
Balance at beginning of period	$ 26,868
Additions due to acquisitions	1,300
Accretion	(17,885)
Reclassification from nonaccretable difference	9,237
Changes in expected cash flows that do not affect nonaccretable difference	4,400
Balance at end of period	$ 23,920

Loans and Leases and Allowan_14

Loans and Leases and Allowance for Credit Losses - Loans modified under terms of TDR (Details) - Loans receivable $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)contract	Dec. 31, 2019USD ($)contract	Dec. 31, 2018USD ($)contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	252	55	64
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 25,932	$ 14,340	$ 7,798
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	30	2	6
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 7,969	$ 148	$ 2,205
Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	236
Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	17,585	14,005	6,858
Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 8,347	$ 335	$ 704
Indirect auto
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract		15	35
Post-Modification Outstanding Recorded Investment by Type of Modification		$ 262	$ 643
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract		0	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment		$ 0	$ 0
Indirect auto | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification		0	0
Indirect auto | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification		0	0
Indirect auto | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification		$ 262	$ 643
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	198	18	9
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 21,248	$ 11,905	$ 5,162
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	26	0	5
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 7,761	$ 0	$ 2,104
Commercial | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	106
Commercial | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	12,928	11,898	5,056
Commercial | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 8,320	$ 7	$ 0
Commercial | Owner occupied commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	8	4	5
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 2,369	$ 1,739	$ 1,387
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	0	0	3
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 1,869
Commercial | Owner occupied commercial real estate | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Owner occupied commercial real estate | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	833	1,739	1,387
Commercial | Owner occupied commercial real estate | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 1,536	$ 0	$ 0
Commercial | Income producing commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	7	3	2
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 11,555	$ 9,013	$ 3,743
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	1	0	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 5,998	$ 0	$ 0
Commercial | Income producing commercial real estate | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	106
Commercial | Income producing commercial real estate | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	4,856	9,013	3,637
Commercial | Income producing commercial real estate | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 6,699	$ 0	$ 0
Commercial | Commercial & industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	4	2	2
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 601	$ 82	$ 32
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	3	0	1
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 819	$ 0	$ 232
Commercial | Commercial & industrial | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Commercial & industrial | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	586	75	32
Commercial | Commercial & industrial | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 15	$ 7	$ 0
Commercial | Construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	7	0	0
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 902	$ 0	$ 0
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	0	0	1
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 0	$ 3
Commercial | Construction | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Construction | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	832	0	0
Commercial | Construction | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 70	$ 0	$ 0
Commercial | Equipment financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	172	9	0
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 5,821	$ 1,071	$ 0
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	22	0	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 944	$ 0	$ 0
Commercial | Equipment financing | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Commercial | Equipment financing | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	5,821	1,071	0
Commercial | Equipment financing | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification		$ 0	$ 0
Residential | Construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	3	1	2
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 123	$ 21	$ 45
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	0	1	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 0	$ 13	$ 0
Residential | Construction | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Residential | Construction | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	123	0	32
Residential | Construction | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 21	$ 13
Residential | Residential mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	40	15	15
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 4,362	$ 2,057	$ 1,900
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	2	1	1
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 145	$ 135	$ 101
Residential | Residential mortgage | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	130
Residential | Residential mortgage | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	4,359	2,057	1,770
Residential | Residential mortgage | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 3	$ 0	$ 0
Residential | Home equity lines of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	4	1	1
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 164	$ 50	$ 41
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	1	0	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 60	$ 0	$ 0
Residential | Home equity lines of credit | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Residential | Home equity lines of credit | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	164	50	0
Residential | Home equity lines of credit | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 0	$ 0	$ 41
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts | contract	7	5	2
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 35	$ 45	$ 7
TDRs Modified Within the Year That Have Subsequently Defaulted, Number of Contracts | contract	1	0	0
TDRs Modified Within the Year That Have Subsequently Defaulted, Recorded Investment	$ 3	$ 0	$ 0
Consumer | Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	0	0	0
Consumer | Structure
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	11	0	0
Consumer | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-Modification Outstanding Recorded Investment by Type of Modification	$ 24	$ 45	$ 7

Loans and Leases and Allowan_15

Loans and Leases and Allowance for Credit Losses - Balance and activity in the ACL by portfolio segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	$ 62,089	$ 61,203	$ 58,914
Allowance for credit losses - loans, Initial ACL - PCD loans	11,152
Allowance for credit losses - loans, Charge-Offs	(32,394)	(18,017)	(13,158)
Allowance for credit losses - loans, Recoveries	14,078	5,801	7,045
Allowance for credit losses - loans, (Release) Provision	75,205	13,102	8,402
Allowance for credit losses - loans, Ending Balance	137,010	62,089	61,203
Allowance for unfunded commitments, Beginning Balance	3,458	3,410	2,312
Allowance for unfunded commitments, (Release) Provision	5,229	48	1,098
Allowance for unfunded commitments, Ending Balance	10,558	3,458	3,410
Total allowance for credit losses, Beginning Balance	65,547	64,613	61,226
Total allowance for credit losses, Initial ACL - PCD loans	11,152
Total allowance for credit losses, Charge-Offs	(32,394)	(18,017)	(13,158)
Total allowance for credit losses, Recoveries	14,078	5,801	7,045
Total allowance for credit losses, (Release) Provision	80,434	13,150	9,500
Total allowance for credit losses, Ending Balance	147,568	65,547	64,613
Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	6,880
Allowance for credit losses - loans, Ending Balance		6,880
Allowance for unfunded commitments, Beginning Balance	1,871
Allowance for unfunded commitments, Ending Balance		1,871
Total allowance for credit losses, Beginning Balance	8,751
Total allowance for credit losses, Ending Balance		8,751
Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	68,969
Allowance for credit losses - loans, Ending Balance		68,969
Allowance for unfunded commitments, Beginning Balance	5,329
Allowance for unfunded commitments, Ending Balance		5,329
Total allowance for credit losses, Beginning Balance	74,298
Total allowance for credit losses, Ending Balance		74,298
Loans receivable | Indirect auto
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	0	999	1,550
Allowance for credit losses - loans, Charge-Offs		(663)	(1,277)
Allowance for credit losses - loans, Recoveries		186	228
Allowance for credit losses - loans, (Release) Provision		(522)	498
Allowance for credit losses - loans, Ending Balance		0	999
Loans receivable | Commercial | Owner occupied commercial real estate
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	11,404	12,207	14,776
Allowance for credit losses - loans, Initial ACL - PCD loans	1,779
Allowance for credit losses - loans, Charge-Offs	(70)	(5)	(303)
Allowance for credit losses - loans, Recoveries	2,565	375	1,227
Allowance for credit losses - loans, (Release) Provision	6,611	(1,173)	(3,493)
Allowance for credit losses - loans, Ending Balance	20,673	11,404	12,207
Loans receivable | Commercial | Owner occupied commercial real estate | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(1,616)
Allowance for credit losses - loans, Ending Balance		(1,616)
Loans receivable | Commercial | Owner occupied commercial real estate | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,788
Allowance for credit losses - loans, Ending Balance		9,788
Loans receivable | Commercial | Income producing commercial real estate
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	12,306	11,073	9,381
Allowance for credit losses - loans, Initial ACL - PCD loans	1,208
Allowance for credit losses - loans, Charge-Offs	(8,430)	(1,227)	(3,304)
Allowance for credit losses - loans, Recoveries	3,546	283	1,064
Allowance for credit losses - loans, (Release) Provision	33,137	2,177	3,932
Allowance for credit losses - loans, Ending Balance	41,737	12,306	11,073
Loans receivable | Commercial | Income producing commercial real estate | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(30)
Allowance for credit losses - loans, Ending Balance		(30)
Loans receivable | Commercial | Income producing commercial real estate | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	12,276
Allowance for credit losses - loans, Ending Balance		12,276
Loans receivable | Commercial | Commercial & industrial
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	5,266	4,802	3,971
Allowance for credit losses - loans, Initial ACL - PCD loans	7,680
Allowance for credit losses - loans, Charge-Offs	(10,707)	(5,849)	(1,669)
Allowance for credit losses - loans, Recoveries	1,371	852	1,390
Allowance for credit losses - loans, (Release) Provision	14,397	5,461	1,110
Allowance for credit losses - loans, Ending Balance	22,019	5,266	4,802
Loans receivable | Commercial | Commercial & industrial | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	4,012
Allowance for credit losses - loans, Ending Balance		4,012
Loans receivable | Commercial | Commercial & industrial | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,278
Allowance for credit losses - loans, Ending Balance		9,278
Loans receivable | Commercial | Construction
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,668	10,337	10,523
Allowance for credit losses - loans, Initial ACL - PCD loans	74
Allowance for credit losses - loans, Charge-Offs	(726)	(290)	(622)
Allowance for credit losses - loans, Recoveries	1,045	1,165	734
Allowance for credit losses - loans, (Release) Provision	3,474	(1,544)	(298)
Allowance for credit losses - loans, Ending Balance	10,952	9,668	10,337
Loans receivable | Commercial | Construction | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(2,583)
Allowance for credit losses - loans, Ending Balance		(2,583)
Loans receivable | Commercial | Construction | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	7,085
Allowance for credit losses - loans, Ending Balance		7,085
Loans receivable | Commercial | Equipment financing
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	7,384	5,452	0
Allowance for credit losses - loans, Initial ACL - PCD loans	0
Allowance for credit losses - loans, Charge-Offs	(8,764)	(5,675)	(1,536)
Allowance for credit losses - loans, Recoveries	2,004	781	460
Allowance for credit losses - loans, (Release) Provision	10,325	6,826	6,528
Allowance for credit losses - loans, Ending Balance	16,820	7,384	5,452
Loans receivable | Commercial | Equipment financing | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	5,871
Allowance for credit losses - loans, Ending Balance		5,871
Loans receivable | Commercial | Equipment financing | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	13,255
Allowance for credit losses - loans, Ending Balance		13,255
Loans receivable | Residential | Construction
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	2,504	2,433	2,729
Allowance for credit losses - loans, Initial ACL - PCD loans	0
Allowance for credit losses - loans, Charge-Offs	(93)	(306)	(54)
Allowance for credit losses - loans, Recoveries	156	157	376
Allowance for credit losses - loans, (Release) Provision	(32)	220	(618)
Allowance for credit losses - loans, Ending Balance	764	2,504	2,433
Loans receivable | Residential | Construction | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(1,771)
Allowance for credit losses - loans, Ending Balance		(1,771)
Loans receivable | Residential | Construction | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	733
Allowance for credit losses - loans, Ending Balance		733
Loans receivable | Residential | Residential mortgage
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	8,081	8,295	10,097
Allowance for credit losses - loans, Initial ACL - PCD loans	195
Allowance for credit losses - loans, Charge-Offs	(398)	(616)	(754)
Allowance for credit losses - loans, Recoveries	455	481	336
Allowance for credit losses - loans, (Release) Provision	5,439	(79)	(1,384)
Allowance for credit losses - loans, Ending Balance	15,341	8,081	8,295
Loans receivable | Residential | Residential mortgage | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	1,569
Allowance for credit losses - loans, Ending Balance		1,569
Loans receivable | Residential | Residential mortgage | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,650
Allowance for credit losses - loans, Ending Balance		9,650
Loans receivable | Residential | Home equity lines of credit
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	4,575	4,752	5,177
Allowance for credit losses - loans, Initial ACL - PCD loans	209
Allowance for credit losses - loans, Charge-Offs	(221)	(996)	(1,194)
Allowance for credit losses - loans, Recoveries	677	610	423
Allowance for credit losses - loans, (Release) Provision	1,258	209	346
Allowance for credit losses - loans, Ending Balance	8,417	4,575	4,752
Loans receivable | Residential | Home equity lines of credit | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	1,919
Allowance for credit losses - loans, Ending Balance		1,919
Loans receivable | Residential | Home equity lines of credit | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	6,494
Allowance for credit losses - loans, Ending Balance		6,494
Loans receivable | Consumer
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	901	853	710
Allowance for credit losses - loans, Initial ACL - PCD loans	7
Allowance for credit losses - loans, Charge-Offs	(2,985)	(2,390)	(2,445)
Allowance for credit losses - loans, Recoveries	2,259	911	807
Allowance for credit losses - loans, (Release) Provision	596	1,527	1,781
Allowance for credit losses - loans, Ending Balance	287	901	$ 853
Loans receivable | Consumer | Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(491)
Allowance for credit losses - loans, Ending Balance		(491)
Loans receivable | Consumer | Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	$ 410
Allowance for credit losses - loans, Ending Balance		$ 410

Loans and Leases and Allowan_16

Loans and Leases and Allowance for Credit Losses - Recorded investment in loans by portfolio segment and the balance of the ACL (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		$ 61,971
Loans Outstanding, Collectively evaluated for impairment		8,691,936
PCI Loans		58,646
Total	$ 11,370,815	8,812,553
Allowance for Credit Losses, Individually evaluated for impairment		2,512
Allowance for Credit Losses, Collectively evaluated for impairment		59,214
Allowance for Credit Losses, PCI		363
Allowance for Credit Losses, Ending balance	137,010	62,089	$ 61,203	$ 58,914
ACL - unfunded commitments, Individually evaluated for impairment		0
ACL - unfunded commitments, Collectively evaluated for impairment		3,458
ACL - unfunded commitments, Ending Balance	10,558	3,458	3,410	2,312
Total ACL, Individually evaluated for impairment		2,512
Total ACL, Collectively evaluated for impairment		62,672
Total ACL, PCI		363
Total ACL, Ending Balance	147,568	65,547	64,613	61,226
Loans receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
PCI Loans		58,646
Total	11,370,815	8,812,553
Loans receivable | Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
PCI Loans		46,947
Total	8,960,888	6,669,593
Loans receivable | Commercial | Owner occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		19,233
Loans Outstanding, Collectively evaluated for impairment		1,692,448
PCI Loans		8,546
Total	2,090,443	1,720,227
Allowance for Credit Losses, Individually evaluated for impairment		816
Allowance for Credit Losses, Collectively evaluated for impairment		10,483
Allowance for Credit Losses, PCI		105
Allowance for Credit Losses, Ending balance	20,673	11,404	12,207	14,776
Loans receivable | Commercial | Income producing commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		18,134
Loans Outstanding, Collectively evaluated for impairment		1,962,588
PCI Loans		27,228
Total	2,540,750	2,007,950
Allowance for Credit Losses, Individually evaluated for impairment		770
Allowance for Credit Losses, Collectively evaluated for impairment		11,507
Allowance for Credit Losses, PCI		29
Allowance for Credit Losses, Ending balance	41,737	12,306	11,073	9,381
Loans receivable | Commercial | Commercial & industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		1,449
Loans Outstanding, Collectively evaluated for impairment		1,218,882
PCI Loans		326
Total	2,498,560	1,220,657
Allowance for Credit Losses, Individually evaluated for impairment		21
Allowance for Credit Losses, Collectively evaluated for impairment		5,193
Allowance for Credit Losses, PCI		52
Allowance for Credit Losses, Ending balance	22,019	5,266	4,802	3,971
Loans receivable | Commercial | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		3,675
Loans Outstanding, Collectively evaluated for impairment		965,678
PCI Loans		6,862
Total	967,305	976,215
Allowance for Credit Losses, Individually evaluated for impairment		55
Allowance for Credit Losses, Collectively evaluated for impairment		9,613
Allowance for Credit Losses, PCI		0
Allowance for Credit Losses, Ending balance	10,952	9,668	10,337	10,523
Loans receivable | Commercial | Equipment financing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		1,027
Loans Outstanding, Collectively evaluated for impairment		739,532
PCI Loans		3,985
Total	863,830	744,544
Allowance for Credit Losses, Individually evaluated for impairment		0
Allowance for Credit Losses, Collectively evaluated for impairment		7,240
Allowance for Credit Losses, PCI		144
Allowance for Credit Losses, Ending balance	16,820	7,384	5,452	0
Loans receivable | Residential | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		1,256
Loans Outstanding, Collectively evaluated for impairment		234,807
PCI Loans		374
Total	281,430	236,437
Allowance for Credit Losses, Individually evaluated for impairment		47
Allowance for Credit Losses, Collectively evaluated for impairment		2,456
Allowance for Credit Losses, PCI		1
Allowance for Credit Losses, Ending balance	764	2,504	2,433	2,729
Loans receivable | Residential | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		15,991
Loans Outstanding, Collectively evaluated for impairment		1,092,046
PCI Loans		9,579
Total	1,284,920	1,117,616
Allowance for Credit Losses, Individually evaluated for impairment		782
Allowance for Credit Losses, Collectively evaluated for impairment		7,296
Allowance for Credit Losses, PCI		3
Allowance for Credit Losses, Ending balance	15,341	8,081	8,295	10,097
Loans receivable | Residential | Home equity lines of credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		992
Loans Outstanding, Collectively evaluated for impairment		658,273
PCI Loans		1,410
Total	697,117	660,675
Allowance for Credit Losses, Individually evaluated for impairment		16
Allowance for Credit Losses, Collectively evaluated for impairment		4,541
Allowance for Credit Losses, PCI		18
Allowance for Credit Losses, Ending balance	8,417	4,575	4,752	5,177
Loans receivable | Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans Outstanding, Individually evaluated for impairment		214
Loans Outstanding, Collectively evaluated for impairment		127,682
PCI Loans		336
Total	146,460	128,232
Allowance for Credit Losses, Individually evaluated for impairment		5
Allowance for Credit Losses, Collectively evaluated for impairment		885
Allowance for Credit Losses, PCI		11
Allowance for Credit Losses, Ending balance	$ 287	$ 901	$ 853	$ 710

Loans and Leases and Allowan_17

Loans and Leases and Allowance for Credit Losses - Loans individually evaluated for impairment by class of loans (Details) - Loans receivable $ in Thousands	Dec. 31, 2019USD ($)
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	$ 28,590
Unpaid Principal Balance, With an ACL recorded	37,395
Unpaid Principal Balance	65,985
Recorded Investment
Recorded Investment, With no related ACL recorded	25,107
Recorded Investment, With an ACL recorded	36,864
Recorded Investment	61,971
ACL Allocated	2,512
Commercial
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	19,315
Unpaid Principal Balance, With an ACL recorded	26,821
Recorded Investment
Recorded Investment, With no related ACL recorded	17,131
Recorded Investment, With an ACL recorded	26,387
ACL Allocated	1,662
Commercial | Owner occupied commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	9,527
Unpaid Principal Balance, With an ACL recorded	11,136
Recorded Investment
Recorded Investment, With no related ACL recorded	8,118
Recorded Investment, With an ACL recorded	11,115
ACL Allocated	816
Commercial | Income producing commercial real estate
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	5,159
Unpaid Principal Balance, With an ACL recorded	13,591
Recorded Investment
Recorded Investment, With no related ACL recorded	4,956
Recorded Investment, With an ACL recorded	13,178
ACL Allocated	770
Commercial | Commercial & industrial
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	1,144
Unpaid Principal Balance, With an ACL recorded	559
Recorded Investment
Recorded Investment, With no related ACL recorded	890
Recorded Investment, With an ACL recorded	559
ACL Allocated	21
Commercial | Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	2,458
Unpaid Principal Balance, With an ACL recorded	1,535
Recorded Investment
Recorded Investment, With no related ACL recorded	2,140
Recorded Investment, With an ACL recorded	1,535
ACL Allocated	55
Commercial | Equipment financing
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	1,027
Unpaid Principal Balance, With an ACL recorded	0
Recorded Investment
Recorded Investment, With no related ACL recorded	1,027
Recorded Investment, With an ACL recorded	0
ACL Allocated	0
Residential | Construction Loans
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	731
Unpaid Principal Balance, With an ACL recorded	643
Recorded Investment
Recorded Investment, With no related ACL recorded	626
Recorded Investment, With an ACL recorded	630
ACL Allocated	47
Residential | Residential mortgage
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	7,362
Unpaid Principal Balance, With an ACL recorded	9,624
Recorded Investment
Recorded Investment, With no related ACL recorded	6,436
Recorded Investment, With an ACL recorded	9,555
ACL Allocated	782
Residential | Home equity lines of credit
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	1,116
Unpaid Principal Balance, With an ACL recorded	146
Recorded Investment
Recorded Investment, With no related ACL recorded	861
Recorded Investment, With an ACL recorded	131
ACL Allocated	16
Consumer
Unpaid Principal Balance
Unpaid Principal Balance, With no related ACL recorded	66
Unpaid Principal Balance, With an ACL recorded	161
Recorded Investment
Recorded Investment, With no related ACL recorded	53
Recorded Investment, With an ACL recorded	161
ACL Allocated	$ 5

Loans and Leases and Allowan_18

Loans and Leases and Allowance for Credit Losses - Average balances of impaired loans and income recognized on impaired loans (Details) - Loans receivable - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Average balances of impaired loans and income recognized on impaired loans
Average Balance	$ 57,223	$ 59,748
Interest Revenue Recognized During Impairment	3,018	3,084
Cash Basis Interest Revenue Received	3,093	3,124
Indirect auto
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,028	1,252
Interest Revenue Recognized During Impairment	50	64
Cash Basis Interest Revenue Received	50	64
Commercial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	38,057	42,043
Interest Revenue Recognized During Impairment	2,099	2,247
Cash Basis Interest Revenue Received	2,170	2,288
Commercial | Owner occupied commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	18,575	19,881
Interest Revenue Recognized During Impairment	1,124	1,078
Cash Basis Interest Revenue Received	1,171	1,119
Commercial | Income producing commercial real estate
Average balances of impaired loans and income recognized on impaired loans
Average Balance	14,253	17,138
Interest Revenue Recognized During Impairment	739	893
Cash Basis Interest Revenue Received	730	895
Commercial | Commercial & industrial
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,837	1,777
Interest Revenue Recognized During Impairment	84	100
Cash Basis Interest Revenue Received	100	100
Commercial | Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	3,233	3,247
Interest Revenue Recognized During Impairment	129	176
Cash Basis Interest Revenue Received	146	174
Commercial | Equipment financing
Average balances of impaired loans and income recognized on impaired loans
Average Balance	159	0
Interest Revenue Recognized During Impairment	23	0
Cash Basis Interest Revenue Received	23	0
Residential | Construction
Average balances of impaired loans and income recognized on impaired loans
Average Balance	1,332	1,405
Interest Revenue Recognized During Impairment	92	96
Cash Basis Interest Revenue Received	94	95
Residential | Residential mortgage
Average balances of impaired loans and income recognized on impaired loans
Average Balance	16,115	14,515
Interest Revenue Recognized During Impairment	748	641
Cash Basis Interest Revenue Received	749	643
Residential | Home equity lines of credit
Average balances of impaired loans and income recognized on impaired loans
Average Balance	488	284
Interest Revenue Recognized During Impairment	14	18
Cash Basis Interest Revenue Received	15	16
Consumer
Average balances of impaired loans and income recognized on impaired loans
Average Balance	203	249
Interest Revenue Recognized During Impairment	15	18
Cash Basis Interest Revenue Received	$ 15	$ 18

Premises and Equipment - Summar

Premises and Equipment - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Premises and equipments
Premises and equipment, gross	$ 360,060	$ 351,477
Less accumulated depreciation	(141,571)	(135,501)
Premises and equipment, net	218,489	215,976
Land and land improvements
Premises and equipments
Premises and equipment, gross	82,816	81,150
Buildings and improvements
Premises and equipments
Premises and equipment, gross	173,497	170,629
Furniture and equipment
Premises and equipments
Premises and equipment, gross	96,157	97,997
Construction in progress
Premises and equipments
Premises and equipment, gross	$ 7,590	$ 1,701

Premises and Equipment - Narrat

Premises and Equipment - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 15.6	$ 15.3	$ 14.2

Derivatives and Hedging Activ_3

Derivatives and Hedging Activities - Fair value of derivative financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Notional Amount	$ 3,529,643
Derivative Assets
Total gross derivative instruments	86,666	$ 35,007
Less: Amounts subject to master netting agreements	(114)	(401)
Less: Cash collateral received/pledged	(3,200)	0
Net amount	83,352	34,606
Derivative Liabilities
Total gross derivative instruments	29,003	15,516
Less: Amounts subject to master netting agreements	(114)	(401)
Less: Cash collateral received/pledged	(27,092)	(14,933)
Net amount	1,797	182
Derivative assets
Derivative Assets
Total gross derivative instruments	86,666	35,007
Derivative liabilities
Derivative Liabilities
Total gross derivative instruments	29,003	15,516
Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	140,000
Designated as hedging instrument | Cash flow hedge of subordinated debt
Derivatives, Fair Value [Line Items]
Notional Amount	100,000
Designated as hedging instrument | Cash flow hedge of trust preferred securities
Derivatives, Fair Value [Line Items]
Notional Amount	20,000
Designated as hedging instrument | Fair value hedge of brokered CDs
Derivatives, Fair Value [Line Items]
Notional Amount	20,000
Designated as hedging instrument | Derivative assets
Derivative Assets
Derivatives designated as hedging instruments	3,378	0
Designated as hedging instrument | Derivative assets | Cash flow hedge of subordinated debt
Derivative Assets
Cash flow hedge	3,378	0
Designated as hedging instrument | Derivative assets | Cash flow hedge of trust preferred securities
Derivative Assets
Cash flow hedge	0	0
Designated as hedging instrument | Derivative assets | Fair value hedge of brokered CDs
Derivative Assets
Fair value hedge	0	0
Designated as hedging instrument | Derivative liabilities
Derivative Liabilities
Derivatives designated as hedging instruments	0	880
Designated as hedging instrument | Derivative liabilities | Cash flow hedge of subordinated debt
Derivative Liabilities
Cash flow hedge	0	0
Designated as hedging instrument | Derivative liabilities | Cash flow hedge of trust preferred securities
Derivative Liabilities
Cash flow hedge	0	0
Designated as hedging instrument | Derivative liabilities | Fair value hedge of brokered CDs
Derivative Liabilities
Fair value hedge	0	880
Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	3,389,643
Not designated as hedging instrument | Customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,329,271
Not designated as hedging instrument | Dealer offsets to customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,329,271
Not designated as hedging instrument | Risk participations
Derivatives, Fair Value [Line Items]
Notional Amount	48,843
Not designated as hedging instrument | Mortgage banking - loan commitment
Derivatives, Fair Value [Line Items]
Notional Amount	253,243
Not designated as hedging instrument | Mortgage banking - forward sales commitment
Derivatives, Fair Value [Line Items]
Notional Amount	325,145
Not designated as hedging instrument | Bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	51,935
Not designated as hedging instrument | Dealer offsets to bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	51,935
Not designated as hedging instrument | Derivative assets
Derivative Assets
Derivatives not designated as hedging instruments	83,288	35,007
Not designated as hedging instrument | Derivative assets | Customer derivative positions
Derivative Assets
Derivatives not designated as hedging instruments	72,508	27,277
Not designated as hedging instrument | Derivative assets | Dealer offsets to customer derivative positions
Derivative Assets
Derivatives not designated as hedging instruments	1	394
Not designated as hedging instrument | Derivative assets | Risk participations
Derivative Assets
Derivatives not designated as hedging instruments	28	0
Not designated as hedging instrument | Derivative assets | Mortgage banking - loan commitment
Derivative Assets
Derivatives not designated as hedging instruments	10,751	1,970
Not designated as hedging instrument | Derivative assets | Mortgage banking - forward sales commitment
Derivative Assets
Derivatives not designated as hedging instruments	0	98
Not designated as hedging instrument | Derivative assets | Bifurcated embedded derivatives
Derivative Assets
Derivatives not designated as hedging instruments	0	5,268
Not designated as hedging instrument | Derivative assets | Dealer offsets to bifurcated embedded derivatives
Derivative Assets
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument | Derivative liabilities
Derivative Liabilities
Derivatives not designated as hedging instruments	29,003	14,636
Not designated as hedging instrument | Derivative liabilities | Customer derivative positions
Derivative Liabilities
Derivatives not designated as hedging instruments	17	446
Not designated as hedging instrument | Derivative liabilities | Dealer offsets to customer derivative positions
Derivative Liabilities
Derivatives not designated as hedging instruments	24,614	6,425
Not designated as hedging instrument | Derivative liabilities | Risk participations
Derivative Liabilities
Derivatives not designated as hedging instruments	12	12
Not designated as hedging instrument | Derivative liabilities | Mortgage banking - loan commitment
Derivative Liabilities
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument | Derivative liabilities | Mortgage banking - forward sales commitment
Derivative Liabilities
Derivatives not designated as hedging instruments	1,964	86
Not designated as hedging instrument | Derivative liabilities | Bifurcated embedded derivatives
Derivative Liabilities
Derivatives not designated as hedging instruments	1,449	0
Not designated as hedging instrument | Derivative liabilities | Dealer offsets to bifurcated embedded derivatives
Derivative Liabilities
Derivatives not designated as hedging instruments	$ 947	$ 7,667

Derivatives and Hedging Activ_4

Derivatives and Hedging Activities - Narrative (Details)	Dec. 31, 2020USD ($)contract	Dec. 31, 2019USD ($)contract
Derivative Instruments [Line Items]
Aggregate notional amount	$ 3,529,643,000
Losses to be reclassified from accumulated other comprehensive income into earnings over the next twelve months	$ 594,000
Interest rate swaps | Cash flow hedging
Derivative Instruments [Line Items]
Number of derivative contracts | contract	3	0
Aggregate notional amount	$ 120,000,000
Interest rate swaps | Fair value hedging of interest rate risk
Derivative Instruments [Line Items]
Number of derivative contracts | contract	2	4
Aggregate notional amount	$ 20,000,000	$ 37,900,000
Not designated as hedging instrument, economic hedge | Interest rate swaps
Derivative Instruments [Line Items]
Number of derivative contracts | contract	3

Derivatives and Hedging Activ_5

Derivatives and Hedging Activities - Effect of derivatives in hedging relationships (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments [Line Items]
Total income (expense) presented in the consolidated statements of income	$ (56,237)	$ (83,312)	$ (61,330)
Interest revenue - taxable investment securities	55,031	69,920	73,496
Other noninterest income	32,213	28,775	24,142
Fair value hedge | Interest expense
Gains (losses) on fair value hedging relationships:
Amounts related to interest settlements on derivatives	291	(327)	(245)
Recognized on derivatives	870	733	(220)
Recognized on hedged items	(880)	(766)	(145)
Net income (expense) recognized on fair value hedges	281	(360)	(610)
Fair value hedge | Interest revenue - taxable investment securities
Gains (losses) on fair value hedging relationships:
Amounts related to interest settlements on derivatives			17
Recognized on derivatives			0
Recognized on hedged items			0
Net income (expense) recognized on fair value hedges			17
Fair value hedge | Other noninterest income
Gains (losses) on fair value hedging relationships:
Amounts related to interest settlements on derivatives			0
Recognized on derivatives			356
Recognized on hedged items			(447)
Net income (expense) recognized on fair value hedges			(91)
Cash flow hedging | Interest expense
Losses on active cash flow hedging relationships:
Realized losses reclassified from AOCI into net income	(359)	0	0
Net expense recognized on cash flow hedges	(359)	$ 0	0
Premium amortization expense excluded from assessment of hedge effectiveness	$ 329
Cash flow hedging | Interest revenue - taxable investment securities
Losses on active cash flow hedging relationships:
Realized losses reclassified from AOCI into net income			0
Net expense recognized on cash flow hedges			0
Cash flow hedging | Other noninterest income
Losses on active cash flow hedging relationships:
Realized losses reclassified from AOCI into net income			0
Net expense recognized on cash flow hedges			$ 0

Derivatives and Hedging Activ_6

Derivatives and Hedging Activities - Carrying amount and hedge accounting basis adjustment (Details) - Fair value hedge - Interest rate swaps - Deposits - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Carrying amount of Assets (Liabilities)	$ (20,216)	$ (35,880)
Hedge Accounting Basis Adjustment	$ (235)	$ 645

Derivatives and Hedging Activ_7

Derivatives and Hedging Activities - Gains and losses recognized in income on derivatives not designated as hedging instruments (Details) - Not designated as hedging instrument - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	$ (1,544)	$ 1,097	$ 4,413
Customer derivatives and dealer offsets | Other noninterest income
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	6,732	2,878	2,658
Bifurcated embedded derivatives and dealer offsets | Other noninterest income
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	(63)	212	307
Interest rate caps | Other noninterest income
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	0	0	501
De-designated hedges | Other noninterest income
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	0	(193)	31
Mortgage banking derivatives | Mortgage loan revenue
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	(7,873)	(1,797)	904
Risk participations | Other noninterest income
Derivative Instruments [Line Items]
Amount of gain (loss) recognized in income on derivatives	$ (340)	$ (3)	$ 12

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Carrying amount of goodwill and other intangible assets
Core deposit intangible	$ 36,162	$ 32,802
Less: accumulated amortization	(22,148)	(17,980)
Net core deposit intangible	14,014	14,822
Goodwill	367,809	327,425	$ 307,112
Total goodwill and other intangible assets, net	$ 381,823	$ 342,247

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Changes in carrying amount of goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in carrying amount of goodwill
Goodwill, beginning balance	$ 327,425	$ 307,112
Acquisitions	40,384	20,313
Goodwill, ending balance	367,809	327,425
Accumulated impairment losses	306,000	306,000	$ 306,000
Gross goodwill	$ 673,000	$ 633,000	$ 613,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Estimated aggregate amortization expense for future periods (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Estimated aggregate amortization expense for future periods
2021	$ 3,622
2022	2,915
2023	2,321
2024	1,834
2025	1,414
Thereafter	1,908
Net core deposit intangible	$ 14,014	$ 14,822

Servicing Assets and Liabilit_3

Servicing Assets and Liabilities - Changes in SBA/USDA loans servicing rights (Details) - SBA/USDA loans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Servicing rights roll forward
Servicing rights, beginning of period	$ 6,794	$ 7,510	$ 7,740
Originated servicing rights capitalized upon sale of loans	1,114	1,835	2,573
Disposals	(624)	(1,258)	(810)
Measurement period adjustment to acquired servicing rights	0	0	(354)
Changes in fair value due to change in inputs or assumptions used in the valuation	(822)	(1,293)	(1,639)
Servicing rights, end of period	$ 6,462	$ 6,794	$ 7,510

Servicing Assets and Liabilit_4

Servicing Assets and Liabilities - Key characteristics, inputs, and economic assumptions for SBA/USDA loans and related sensitivity (Details) - SBA/USDA loans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Servicing Assets at Fair Value [Line Items]
Fair value of retained servicing assets	$ 6,462	$ 6,794	$ 7,510	$ 7,740
10% adverse change	(358)	(352)
20% adverse change	(680)	(671)
100 bps adverse change	(171)	(184)
200 bps adverse change	$ (333)	$ (358)
Weighted average
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	17.80%	16.50%
Discount rate	8.90%	12.30%
Life (years)	3 years 6 months	3 years 10 months 24 days
Gross margin	1.90%	1.90%
Minimum
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	2.70%
Discount rate	1.60%
Life (years)	7 months 6 days
Gross margin	0.00%
Maximum
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	33.60%
Discount rate	44.10%
Life (years)	5 years 7 months 6 days
Gross margin	3.20%

Servicing Assets and Liabilit_5

Servicing Assets and Liabilities - Changes in residential mortgage loans servicing rights (Details) - Residential mortgage servicing rights - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Servicing rights roll forward
Servicing rights, beginning of period	$ 13,565	$ 11,877	$ 8,262
Originated servicing rights capitalized upon sale of loans	11,911	5,783	4,587
Disposals	(2,868)	(1,098)	(537)
Changes in fair value due to change in inputs or assumptions used in the valuation	(6,392)	(2,997)	(435)
Servicing rights, end of period	$ 16,216	$ 13,565	$ 11,877

Servicing Assets and Liabilit_6

Servicing Assets and Liabilities - Key characteristics, inputs, and economic assumptions for residential mortgage loans and related sensitivity (Details) - Residential mortgage servicing rights - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Servicing Assets at Fair Value [Line Items]
Fair value of retained servicing assets	$ 16,216	$ 13,565	$ 11,877	$ 8,262
10% adverse change	(999)	(662)
20% adverse change	(1,912)	(1,270)
100 bps adverse change	(518)	(467)
200 bps adverse change	$ (1,001)	$ (900)
Weighted average
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	17.70%	14.10%
Discount rate	10.00%	10.00%
Minimum
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	8.70%
Discount rate	10.00%
Maximum
Servicing Assets at Fair Value [Line Items]
Prepayment rate assumption	19.50%
Discount rate	11.00%

Servicing Assets and Liabilit_7

Servicing Assets and Liabilities - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Servicing Asset [Line Items]
Servicing liabilities	$ 357	$ 363
SBA/USDA loans
Schedule Of Servicing Asset [Line Items]
Loans serviced for others not included in balance sheet	402,000	411,000
Contractually specified servicing fees earned by United on servicing rights	3,770	3,820	$ 3,440
Residential mortgage servicing rights
Schedule Of Servicing Asset [Line Items]
Loans serviced for others not included in balance sheet	2,310,000	1,600,000
Contractually specified servicing fees earned by United on servicing rights	4,820	3,670	$ 2,370
Equipment financing loans
Schedule Of Servicing Asset [Line Items]
Loans serviced for others not included in balance sheet	$ 45,500	$ 42,400

Time Deposits - Contractual mat

Time Deposits - Contractual maturities of time deposits (Details) $ in Thousands	Dec. 31, 2020USD ($)
Contractual maturities of time deposits
2021	$ 1,418,807
2022	211,523
2023	59,153
2024	25,513
2025	20,816
Thereafter	50,579
Total time deposits	$ 1,786,391

Time Deposits - Narrative (Deta

Time Deposits - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deposits [Abstract]
Time deposits (excluding brokered time deposits) that met or exceeded FDIC insurance limit	$ 317	$ 367

Long-term Debt - Schedule of lo

Long-term Debt - Schedule of long-term debt (Details) - USD ($) $ in Thousands	12 Months Ended	29 Months Ended		64 Months Ended	67 Months Ended	71 Months Ended
	Dec. 31, 2020	Dec. 31, 2027	Dec. 31, 2022	Dec. 31, 2026	Dec. 31, 2030	Dec. 31, 2028	Dec. 31, 2019
Debt Instrument [Line Items]
Less net discount	$ (9,296)						$ (8,588)
Total long-term debt	326,956						212,664
Senior debentures
Debt Instrument [Line Items]
Long-term debt, gross	185,000						85,000
Senior debentures | 2022 senior debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,000						50,000
Interest Rate (percent)	5.00%
Senior debentures | 2022 senior debentures | LIBOR | Forecast
Debt Instrument [Line Items]
Basis spread on variable rate (percent)			3.814%
Senior debentures | 2027 senior debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 35,000						35,000
Interest Rate (percent)	5.50%
Senior debentures | 2027 senior debentures | LIBOR | Forecast
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		3.71%
Senior debentures | 2030 senior debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000						0
Interest Rate (percent)	5.00%
Senior debentures | 2030 senior debentures | SOFR | Forecast
Debt Instrument [Line Items]
Basis spread on variable rate (percent)					4.87%
Subordinated debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 111,250						111,250
Subordinated debentures | 2026 subordinated debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 15,000						0
Interest Rate (percent)	5.875%
Subordinated debentures | 2026 subordinated debentures | LIBOR | Forecast
Debt Instrument [Line Items]
Basis spread on variable rate (percent)				4.70%
Subordinated debentures | 2028 subordinated debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000						100,000
Interest Rate (percent)	4.50%
Subordinated debentures | 2028 subordinated debentures | LIBOR | Forecast
Debt Instrument [Line Items]
Basis spread on variable rate (percent)						2.12%
Subordinated debentures | 2025 subordinated debentures
Debt Instrument [Line Items]
Long-term debt, gross	$ 11,250						11,250
Interest Rate (percent)	6.25%
Trust preferred securities
Debt Instrument [Line Items]
Long-term debt, gross	$ 25,002						25,002
Trust preferred securities | Southern Bancorp Capital Trust I
Debt Instrument [Line Items]
Long-term debt, gross	$ 4,382						4,382
Trust preferred securities | Southern Bancorp Capital Trust I | Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	1.00%
Trust preferred securities | Tidelands Statutory Trust I
Debt Instrument [Line Items]
Long-term debt, gross	$ 8,248						8,248
Trust preferred securities | Tidelands Statutory Trust I | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	1.38%
Trust preferred securities | Four Oaks Statutory Trust I
Debt Instrument [Line Items]
Long-term debt, gross	$ 12,372						$ 12,372
Trust preferred securities | Four Oaks Statutory Trust I | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	1.35%

Operating Leases - Right-of-use

Operating Leases - Right-of-use asset and operating lease liability (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Right-of-use asset	$ 31,398	$ 19,894
Operating lease liability	$ 33,095	$ 22,039
Right-of-use asset, balance sheet line item	us-gaap:OtherAssets	us-gaap:OtherAssets
Operating lease liability, balance sheet line item	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities

Operating Leases - Narrative (D

Operating Leases - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Right-of-use assets resulting in net increase in operating lease liability	$ 17,400
Rent expense in accordance with ASC 840		$ 4,700
Operating lease, weighted average remaining lease term (in years)	5 years 8 months 26 days
Operating lease, weighted average discount rate (percent)	1.79%
Three Shores
Lessee, Lease, Description [Line Items]
Right-of-use assets resulting in net increase in operating lease liability	$ 15,100

Operating Leases - Operating le

Operating Leases - Operating lease income and expense and other supplemental information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating lease income and expense
Operating lease cost	$ 6,449	$ 5,067
Variable lease cost	757	449
Short-term lease cost	100	136
Total lease cost	7,306	5,652
Sublease income and rental income from owned properties under operating leases	$ 1,022	$ 1,160

Operating Leases - Future minim

Operating Leases - Future minimum lease payments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Future minimum lease payments
2021	$ 7,446
2022	7,544
2023	6,953
2024	3,417
2025	2,403
Thereafter	6,996
Total	34,759
Less discount	(1,664)
Present value of lease liability	$ 33,095	$ 22,039

Fair Value Measurements - Asset

Fair Value Measurements - Assets and liabilities measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets:
Debt securities available-for-sale	$ 3,224,721	$ 2,274,581
Mortgage loans held for sale	105,433	58,484
U.S. Treasuries
Assets:
Debt securities available-for-sale	128,072	154,618
U.S. Government agencies & GSEs
Assets:
Debt securities available-for-sale	152,972	3,035
State and political subdivisions
Assets:
Debt securities available-for-sale	274,472	226,490
Corporate bonds
Assets:
Debt securities available-for-sale	71,767	203,091
Asset-backed securities
Assets:
Debt securities available-for-sale	562,722	103,369
Recurring
Assets:
Equity securities with readily determinable fair values	1,687	1,973
Mortgage loans held for sale	105,433	58,484
Deferred compensation plan assets	9,584	8,133
Servicing rights for SBA/USDA loans	6,462	6,794
Residential mortgage servicing rights	16,216	13,565
Derivative financial instruments	86,666	35,007
Total assets	3,450,769	2,398,537
Liabilities:
Deferred compensation plan liability	9,590	8,132
Derivative financial instruments	29,003	15,516
Total liabilities	38,593	23,648
Recurring | U.S. Treasuries
Assets:
Debt securities available-for-sale	128,072	154,618
Recurring | U.S. Government agencies & GSEs
Assets:
Debt securities available-for-sale	152,972	3,035
Recurring | State and political subdivisions
Assets:
Debt securities available-for-sale	274,472	226,490
Recurring | Residential mortgage-backed securities
Assets:
Debt securities available-for-sale	1,485,585	1,299,025
Recurring | Commercial mortgage-backed securities
Assets:
Debt securities available-for-sale	549,131	284,953
Recurring | Corporate bonds
Assets:
Debt securities available-for-sale	71,767	203,091
Recurring | Asset-backed securities
Assets:
Debt securities available-for-sale	562,722	103,369
Recurring | Level 1
Assets:
Equity securities with readily determinable fair values	774	1,973
Mortgage loans held for sale	0	0
Deferred compensation plan assets	9,584	8,133
Servicing rights for SBA/USDA loans	0	0
Residential mortgage servicing rights	0	0
Derivative financial instruments	0	0
Total assets	138,430	164,724
Liabilities:
Deferred compensation plan liability	9,590	8,132
Derivative financial instruments	0	0
Total liabilities	9,590	8,132
Recurring | Level 1 | U.S. Treasuries
Assets:
Debt securities available-for-sale	128,072	154,618
Recurring | Level 1 | U.S. Government agencies & GSEs
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 1 | State and political subdivisions
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 1 | Residential mortgage-backed securities
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 1 | Commercial mortgage-backed securities
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 1 | Corporate bonds
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 1 | Asset-backed securities
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 2
Assets:
Equity securities with readily determinable fair values	913	0
Mortgage loans held for sale	105,433	58,484
Deferred compensation plan assets	0	0
Servicing rights for SBA/USDA loans	0	0
Residential mortgage servicing rights	0	0
Derivative financial instruments	75,887	27,769
Total assets	3,277,132	2,205,218
Liabilities:
Deferred compensation plan liability	0	0
Derivative financial instruments	26,595	6,957
Total liabilities	26,595	6,957
Recurring | Level 2 | U.S. Treasuries
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 2 | U.S. Government agencies & GSEs
Assets:
Debt securities available-for-sale	152,972	3,035
Recurring | Level 2 | State and political subdivisions
Assets:
Debt securities available-for-sale	274,472	226,490
Recurring | Level 2 | Residential mortgage-backed securities
Assets:
Debt securities available-for-sale	1,485,585	1,299,025
Recurring | Level 2 | Commercial mortgage-backed securities
Assets:
Debt securities available-for-sale	549,131	284,953
Recurring | Level 2 | Corporate bonds
Assets:
Debt securities available-for-sale	70,017	202,093
Recurring | Level 2 | Asset-backed securities
Assets:
Debt securities available-for-sale	562,722	103,369
Recurring | Level 3
Assets:
Equity securities with readily determinable fair values	0	0
Mortgage loans held for sale	0	0
Deferred compensation plan assets	0	0
Servicing rights for SBA/USDA loans	6,462	6,794
Residential mortgage servicing rights	16,216	13,565
Derivative financial instruments	10,779	7,238
Total assets	35,207	28,595
Liabilities:
Deferred compensation plan liability	0	0
Derivative financial instruments	2,408	8,559
Total liabilities	2,408	8,559
Recurring | Level 3 | U.S. Treasuries
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 3 | U.S. Government agencies & GSEs
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 3 | State and political subdivisions
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 3 | Residential mortgage-backed securities
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 3 | Commercial mortgage-backed securities
Assets:
Debt securities available-for-sale	0	0
Recurring | Level 3 | Corporate bonds
Assets:
Debt securities available-for-sale	1,750	998
Recurring | Level 3 | Asset-backed securities
Assets:
Debt securities available-for-sale	$ 0	$ 0

Fair Value Measurements - Recon

Fair Value Measurements - Reconciliation for measurements at fair value on a recurring basis using significant unobservable inputs (Details) - Recurring - Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Asset
Reconciliation of Assets at Level 3 Measurement
Balance at beginning of period	$ 7,238	$ 11,841	$ 12,207
Transfers into Level 3	583
Additions	368
Sales and settlements	0	(1,135)	(1,029)
Other comprehensive income	0	0	0
Amounts included in earnings - fair value adjustments	2,590	(3,468)	663
Balance at end of period	10,779	7,238	11,841
Debt Securities Available- for-Sale
Reconciliation of Assets at Level 3 Measurement
Balance at beginning of period	998	995	900
Transfers into Level 3	0
Additions	1,750
Sales and settlements	(1,000)	0	0
Other comprehensive income	2	3	95
Amounts included in earnings - fair value adjustments	0	0	0
Balance at end of period	1,750	998	995
Derivative Liability
Reconciliation of Liabilities at Level 3 Measurement
Balance at beginning of period	8,559	15,732	16,744
Transfers into Level 3	0
Additions	0
Sales and settlements	0	(2,330)	(1,347)
Other comprehensive income	0	0	0
Amounts included in earnings - fair value adjustments	(6,151)	(4,843)	335
Balance at end of period	$ 2,408	$ 8,559	$ 15,732

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative information about Level 3 measurements for fair value on a recurring basis (Details) - Recurring - Level 3	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Corporate bonds
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation technique	Indicative bid provided by a broker
Derivative assets - mortgage
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation technique	Internal model
Derivative assets - mortgage | Pull through rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.656
Derivative assets - mortgage | Pull through rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - mortgage | Pull through rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.839	0.836
Derivative assets - customer derivative positions
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation technique	Internal model
Derivative assets - customer derivative positions | Probability of default rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - customer derivative positions | Probability of default rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - customer derivative positions | Probability of default rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - customer derivative positions | Loss given default rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - customer derivative positions | Loss given default rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets - customer derivative positions | Loss given default rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1
Derivative assets & liabilities - risk participations
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation technique	Internal model
Derivative assets & liabilities - risk participations | Probability of default rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.0016
Derivative assets & liabilities - risk participations | Probability of default rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.131
Derivative assets & liabilities - risk participations | Probability of default rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.0403	0.0180
Derivative assets & liabilities - risk participations | Probable exposure rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.0006
Derivative assets & liabilities - risk participations | Probable exposure rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.0366
Derivative assets & liabilities - risk participations | Probable exposure rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets and liabilities, measurement input	0.0181	0.0036
Derivative assets & liabilities - other
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Valuation technique	Dealer priced

Fair Value Measurements - Fair

Fair Value Measurements - Fair value option (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Mortgage Loans Held for Sale
Outstanding principal balance	$ 99,746	$ 56,613
Fair value	105,433	58,484
Mortgage loan gains and other related fees	$ 3,815	$ 1,177	$ (133)

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets and liabilities measured at fair value on nonrecurring basis (Details) - Nonrecurring - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 29,404	$ 20,977
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 29,404	$ 20,977

Fair Value Measurements - Fai_2

Fair Value Measurements - Fair values for other financial instruments that are not measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets:
Securities held to maturity	$ 437,193	$ 287,904
Carrying Amount
Assets:
Securities held to maturity	420,361	283,533
Loans, net	11,233,805	8,750,464
Liabilities:
Deposits	15,232,358	10,897,244
Long-term debt	326,956	212,664
Fair Value
Assets:
Securities held to maturity	437,193	287,904
Loans, net	11,209,717	8,714,592
Liabilities:
Deposits	15,232,274	10,897,465
Long-term debt	336,763	217,665
Fair Value | Level 1
Assets:
Securities held to maturity	0	0
Loans, net	0	0
Liabilities:
Deposits	0	0
Long-term debt	0	0
Fair Value | Level 2
Assets:
Securities held to maturity	437,193	287,904
Loans, net	0	0
Liabilities:
Deposits	15,232,274	10,897,465
Long-term debt	0	0
Fair Value | Level 3
Assets:
Securities held to maturity	0	0
Loans, net	11,209,717	8,714,592
Liabilities:
Deposits	0	0
Long-term debt	$ 336,763	$ 217,665

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Maximum remaining maturity of financial instruments having no defined maturity	180 days

Common and Preferred Stock (Det

Common and Preferred Stock (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2020
Class of Stock [Line Items]
Repurchase program authorized amount	$ 50,000,000			$ 50,000,000
Shares repurchased (in shares)	826,482	500,495	0
Repurchase program remaining authorization	$ 50,000,000
Shares issued in connection with DRIP (in shares)	38,107	62,629	7,307
Preferred stock authorized (in shares)	10,000,000
Preferred stock carrying amount	$ 96,422,000	$ 0
Net proceeds from issuance of preferred stock	96,422,000	0	$ 0
Series I perpetual non-cumulative preferred stock
Class of Stock [Line Items]
Preferred stock carrying amount	96,400,000	$ 0
Preferred stock issued	$ 100,000,000
Issuance of stock (in shares)	4,000
Preferred stock dividend rate (percent)	6.875%
Net proceeds from issuance of preferred stock	$ 96,400,000
Preferred stock redemption price (in dollars per share)	$ 25,000
Depositary share on Series I perpetual non-cumulative preferred stock
Class of Stock [Line Items]
Preferred stock redemption price (in dollars per share)	$ 25

Equity Compensation Plans - Res

Equity Compensation Plans - Restricted stock units and options outstanding activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Stock Units
Restricted Stock Units, Shares
Beginning balance, outstanding (in shares)	808,424	759,746	663,817
Granted (in shares)	446,512	315,827	416,484
Vested / Exercised (in shares)	(324,697)	(216,138)	(290,013)
Expired (in shares)	0	0
Cancelled (in shares)	(36,808)	(51,011)	(30,542)
Ending balance, outstanding (in shares)	893,431	808,424	759,746
Restricted Stock Units, Weighted Average Grant Date Fair Value
Beginning balance, outstanding (in dollars per share)	$ 27.94	$ 27.66	$ 22.40
Granted (in dollars per share)	19.15	26.74	30.54
Vested / Exercised (in dollars per share)	26.42	25.38	20.18
Expired (in dollars per share)
Cancelled (in dollars per share)	25.73	27.18	23.65
Ending balance, outstanding (in dollars per share)	$ 23.75	$ 27.94	$ 27.66
Vested, Aggregate Intrinsic Value	$ 7,212
Outstanding, Aggregate Intrinsic Value	$ 25,409
Options
Options, Shares
Beginning balance, outstanding (in shares)	1,500	47,139	60,287
Granted (in shares)	0	0	0
Vested / Exercised (in shares)	0	(13,000)	(12,000)
Expired (in shares)	(1,500)	(30,243)
Cancelled (in shares)	0	(2,396)	(1,148)
Ending balance, outstanding (in shares)	0	1,500	47,139
Options, Weighted Average Exercise Price
Beginning balance, outstanding (in dollars per share)	$ 27.95	$ 27.07	$ 24.12
Granted (in dollars per share)	0	0	0
Vested / Exercised (in dollars per shares)	0	16.34	11.85
Expired (in dollars per share)	27.95	31.43
Cancelled (in dollars per share)	$ 0	29.68	31.50
Ending balance, outstanding (in dollars per share)		$ 27.95	$ 27.07

Equity Compensation Plans - Nar

Equity Compensation Plans - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period under plan	4 years
Exercisable period	10 years
Additional awards remaining available under plan (in shares)	908,000
Deferred income tax benefit related to compensation expense for awards	$ 2,010,000	$ 2,390,000	$ 1,540,000
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0	0	18,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 7,400,000	$ 8,980,000	$ 5,690,000
Units outstanding (in shares)	893,431	808,424	759,746	663,817
Unrecognized compensation cost	$ 14,400,000
Weighted-average recognition period for unrecognized compensation cost	2 years 7 months 6 days
Restricted stock units | Merger-related and other charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to acceleration of vesting		$ 1,380,000
Compensation expense related to acquisition		740,000
Restricted stock units | Salaries and employee benefits expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		6,860,000
Restricted stock units | Other operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 484,000	$ 379,000	$ 338,000
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units outstanding (in shares)	148,109

Reclassifications Out of AOCI_2

Reclassifications Out of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Securities gains (losses), net	$ 748	$ (1,021)	$ (656)
Investment securities interest revenue	557,996	552,706	500,080
Salaries and employee benefits expense	(224,060)	(196,440)	(181,015)
Other expense	(15,301)	(15,092)	(17,194)
Deposit interest expense	(41,772)	(66,856)	(39,543)
Long-term debt interest expense	(14,434)	(12,921)	(14,330)
Merger-related and other	(7,018)	(6,907)	(5,414)
Total before tax	209,445	238,712	215,926
Income tax benefit	(45,356)	(52,991)	(49,815)
Net income	164,089	185,721	166,111
Reclassifications Out of AOCI
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income	(899)	(2,997)	(2,113)
Reclassifications Out of AOCI | Realized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Securities gains (losses), net	748	(1,021)	(656)
Income tax benefit	(191)	247	132
Net income	557	(774)	(524)
Reclassifications Out of AOCI | Amortization of losses included in net income on available-for-sale securities transferred to held to maturity
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Investment securities interest revenue	(723)	(383)	(739)
Income tax benefit	173	92	180
Net income	(550)	(291)	(559)
Reclassifications Out of AOCI | Reclassifications related to derivative financial instruments accounted for as cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other expense	0	(235)	0
Deposit interest expense	0	(102)	(499)
Long-term debt interest expense	(359)	0	0
Total before tax	(359)	(337)	(499)
Income tax benefit	91	86	129
Net income	(268)	(251)	(370)
Reclassifications Out of AOCI | Reclassifications related to defined benefit pension plan activity
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(857)	(2,257)	(907)
Income tax benefit	219	576	247
Net income	(638)	(1,681)	(660)
Reclassifications Out of AOCI | Prior service cost
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits expense	(531)	(640)	(666)
Reclassifications Out of AOCI | Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other expense	(326)	(59)	(241)
Reclassifications Out of AOCI | Termination of Funded Plan
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Merger-related and other	$ 0	$ (1,558)	$ 0

Earnings Per Share - Computatio

Earnings Per Share - Computation of basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Computation of basic and diluted earnings per share
Net income	$ 164,089	$ 185,721	$ 166,111
Undistributed earnings allocated to participating securities	(1,287)	(1,375)	(1,184)
Dividends on preferred stock	(3,533)	0	0
Net income available to common shareholders	$ 159,269	$ 184,346	$ 164,927
Net income per common share:
Basic (in dollars per share)	$ 1.91	$ 2.31	$ 2.07
Diluted (in dollars per share)	$ 1.91	$ 2.31	$ 2.07
Weighted average common shares:
Basic (in shares)	83,184	79,700	79,662
Effect of dilutive securities:
Diluted (in shares)	83,248	79,708	79,671
Stock options
Effect of dilutive securities:
Dilutive securities (in shares)	0	1	7
Restricted stock units
Effect of dilutive securities:
Dilutive securities (in shares)	64	7	2

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Antidilutive securities excluded from computation (in shares)	0
Stock options
Class of Stock [Line Items]
Antidilutive securities excluded from computation (in shares)		1,000	32,316
Weighted average exercise price of stock options (in dollars per share)		$ 30.45
Restricted stock units
Class of Stock [Line Items]
Antidilutive securities excluded from computation (in shares)		183,168

Income Taxes - Income tax expen

Income Taxes - Income tax expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Current	$ 42,688	$ 38,082	$ 17,185
Deferred	2,668	14,909	32,630
Total income tax expense	$ 45,356	$ 52,991	$ 49,815

Income Taxes - Differences betw

Income Taxes - Differences between provision for income taxes and amount computed as statutory rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Differences between the provision for income taxes and statutory federal income tax rate
Pretax income at statutory rates	$ 43,983	$ 50,130	$ 45,344
Add (deduct):
State taxes, net of federal benefit	5,928	7,168	6,765
BOLI earnings	(1,052)	(1,127)	(747)
Adjustment to reserve for uncertain tax positions	(1,212)	84	80
Tax-exempt interest revenue	(2,169)	(1,827)	(1,229)
Equity compensation	(174)	(375)	(892)
Transaction costs	217	16	78
Tax credit investments	(930)	(464)	(29)
Change in state statutory tax rate	0	0	583
Other	765	(614)	(138)
Total income tax expense	$ 45,356	$ 52,991	$ 49,815

Income Taxes - Deferred taxes (

Income Taxes - Deferred taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
DTAs:
ACL	$ 33,213	$ 14,910
Net operating loss carryforwards	22,277	27,568
Deferred compensation	10,012	9,363
Loan purchase accounting adjustments	8,567	6,599
Reserve for losses on foreclosed properties	33	20
Nonqualified share based compensation	1,833	2,041
Accrued expenses	6,865	3,958
Investment in partnerships	71	67
Unamortized pension actuarial losses and prior service cost	1,981	1,739
Securities purchase accounting adjustments	0	687
Lease liability	8,055	5,327
Other	4,018	1,351
Total DTAs	96,925	73,630
DTLs:
Unrealized gains on securities available-for-sale	17,439	7,943
Unrealized gains on cash flow hedges	54	0
Acquired intangible assets	2,576	2,530
Premises and equipment	4,241	3,002
Loan origination costs	4,857	3,538
True tax leases	7,846	7,783
Prepaid expenses	230	373
Servicing assets	4,816	4,428
Derivatives	2,250	1,075
Right-of-use asset	7,642	4,809
Securities purchase accounting adjustments	3,146	0
Uncertain tax positions	1,813	1,792
Total DTLs	56,910	37,273
Less valuation allowance	1,604	2,298
Net DTA	$ 38,411	$ 34,059

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of the beginning and ending unrecognized tax benefit
Balance at beginning of year	$ 3,370	$ 3,264	$ 3,163
Additions based on tax positions related to the current year	421	481	470
Decreases resulting from a lapse in the applicable statute of limitations	(1,628)	(375)	(369)
Balance at end of year	$ 2,163	$ 3,370	$ 3,264

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Tax Credit Carryforward [Line Items]
Increase in net DTA	$ 16,300,000
Valuation allowance	1,604,000	$ 2,298,000
Net DTA	38,411,000	34,059,000
Tax benefit related to uncertain tax positions that increases income from continuing operations	1,710,000
Penalties and interest related to income taxes	0	0	$ 0
Accrued penalties and interest	0	$ 0
Begin to expire in 2021 | State
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	36,000,000
State tax credits	3,700,000
Begin to expire in 2031 | State
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	113,000,000
Begin to expire in 2027 | Federal
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	$ 63,800,000

Benefit Plans - Narrative (Deta

Benefit Plans - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Employer match of employee contributions (percent)		100.00%
Employer matching contribution maximum percent of employee's eligible compensation (percent)		5.00%
Service period to receive matching contribution		1 year
Vesting period of benefits			3 years
Compensation expense related to 401(k) Plan		$ 6,160,000	$ 5,300,000	$ 4,730,000
Common stock issuable under the deferred compensation plan (shares)		600,834	664,640
Unrecognized losses previously in accumulated other income (loss) recognized upon fund liquidation		$ 0	$ 1,558,000	$ 0
Shares issued through ESPP (in shares)		34,423	20,928	17,941
Executive officers, certain key employees, and board of directors
Defined Benefit Plan Disclosure [Line Items]
Matching contributions to deferred compensation plan		$ 49,000	$ 162,000	$ 119,000
Discretionary contributions to deferred compensation plan		0	0	$ 0
Funded Plan | Defined benefit plan
Defined Benefit Plan Disclosure [Line Items]
United contributions to the plan	$ 4,900,000
Unrecognized losses previously in accumulated other income (loss) recognized upon fund liquidation			1,560,000
Pension plan settlement expense			1,380,000
Total settlement loss upon plan termination			2,940,000
Modified Retirement Plan | Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
United contributions to the plan		1,193,000	730,000
Estimated net loss to be amortized in next fiscal year		575,000
Estimated prior service costs to be amortized in next fiscal year		$ 469,000
Funded Plan | Funded Plan
Defined Benefit Plan Disclosure [Line Items]
United contributions to the plan			$ 4,898,000

Benefit Plans - Weighted-averag

Benefit Plans - Weighted-average assumptions to determine pension benefit obligation (Details) - Modified Retirement Plan - Unfunded Plan	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Discount rate for disclosures (percent)	2.55%	3.25%
Discount rate for net periodic benefit cost (percent)	3.25%	4.40%

Benefit Plans - Changes in obli

Benefit Plans - Changes in obligations and plan assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Modified Retirement Plan | Unfunded Plan
Accumulated benefit obligation:
Accumulated benefit obligation - beginning of year	$ 25,105	$ 21,736
Service cost	588	392	$ 363
Interest cost	795	931	801
Plan amendments	0	386
Actuarial losses	1,804	2,390
Benefits paid	(1,193)	(730)
Accumulated benefit obligation - end of year	27,099	25,105	21,736
Change in plan assets, at fair value:
Beginning plan assets	0	0
Actual return	0	0
Employer contribution	1,193	730
Benefits paid	(1,193)	(730)
Plan assets - end of year	0	0	0
Funded status - end of year (plan assets less benefit obligations)	(27,099)	(25,105)
Funded Plan | Funded Plan
Accumulated benefit obligation:
Accumulated benefit obligation - beginning of year	0	16,011
Service cost		0	0
Interest cost		166	647
Plan amendments		0
Actuarial losses		1,489
Benefits paid		(17,666)
Accumulated benefit obligation - end of year		0	16,011
Change in plan assets, at fair value:
Beginning plan assets	$ 0	12,595
Actual return		173
Employer contribution		4,898
Benefits paid		(17,666)
Plan assets - end of year		0	$ 12,595
Funded status - end of year (plan assets less benefit obligations)		$ 0

Benefit Plans - Components of n

Benefit Plans - Components of net periodic benefit cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Modified Retirement Plan | Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 588	$ 392	$ 363
Interest cost	795	931	801
Expected return on plan assets	0	0	0
Amortization of prior service cost	531	635	666
Amortization of net actuarial losses	326	59	241
Net periodic benefit cost	$ 2,240	2,017	2,071
Funded Plan | Funded Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost		0	0
Interest cost		166	647
Expected return on plan assets		(106)	(551)
Amortization of prior service cost		0	0
Amortization of net actuarial losses		0	0
Net periodic benefit cost		$ 60	$ 96

Benefit Plans - Estimated futur

Benefit Plans - Estimated future benefit payments expected to be paid (Details) - Modified Retirement Plan - Unfunded Plan $ in Thousands	Dec. 31, 2020USD ($)
Defined Benefit Plan Disclosure [Line Items]
2021	$ 1,170
2022	1,165
2023	1,159
2024	1,152
2025	1,195
2026-2030	$ 7,675

Regulatory Matters - Regulatory

Regulatory Matters - Regulatory capital ratios and minimum amounts required (Details) $ in Thousands	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Risk-based ratios:
CET1 capital, Minimum	0.045
CET1 capital, Well Capitalized	0.065
CET1 capital	0.1231	0.1297
Tier 1 capital, Minimum	0.060
Tier 1 capital, Well Capitalized	0.080
Tier 1 capital	0.1310	0.1321
Total capital, Minimum	0.080
Total capital, Well Capitalized	0.100
Total capital	0.1515	0.1501
Tier 1 leverage ratio, Minimum	0.040
Tier 1 leverage ratio, Well Capitalized	0.050
Tier 1 leverage ratio	0.0928	0.1034
CET1 capital	$ 1,506,750	$ 1,275,148
Tier 1 capital	1,603,172	1,299,398
Total capital	1,854,368	1,476,302
RWAs	12,240,440	9,834,051
Average total assets	$ 17,276,853	$ 12,568,563
United Community Bank
Risk-based ratios:
CET1 capital	0.1331	0.1487
Tier 1 capital	0.1331	0.1487
Total capital	0.1428	0.1554
Tier 1 leverage ratio	0.0942	0.1163
CET1 capital	$ 1,625,292	$ 1,458,720
Tier 1 capital	1,625,292	1,458,720
Total capital	1,743,045	1,524,267
RWAs	12,207,940	9,810,477
Average total assets	$ 17,246,878	$ 12,545,254

Regulatory Matters - Narrative

Regulatory Matters - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Regulatory Capital Requirements Under Banking Regulations [Abstract]
Cash dividend from Bank paid to Holding Company	$ 150	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Contractual amount of off-balance sheet instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Financial instruments	$ 3,052,657	$ 2,126,275
Letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Financial instruments	$ 31,748	$ 22,533

Commitments and Contingencies_2

Commitments and Contingencies - Narrative (Details) $ in Thousands	Dec. 31, 2020USD ($)
Commitments and Contingencies Disclosure [Abstract]
Investment in limited partnerships	$ 58,300
Commitment for additional fund	$ 9,810

Condensed Financial Statement_3

Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only) - Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
ASSETS
Other assets	$ 226,405	$ 171,135
Total assets	17,794,374	12,916,016
LIABILITIES AND SHAREHOLDERS’ EQUITY
Long-term debt	326,956	212,664
Total liabilities	15,786,844	11,280,324
Shareholders’ equity	2,007,530	1,635,692	$ 1,457,554	$ 1,303,334
Total liabilities and shareholders’ equity	17,794,374	12,916,016
Holding Company
ASSETS
Cash and cash equivalents	289,243	32,495
Investment in bank	2,028,965	1,814,414
Investment in other subsidiaries	752	752
Other assets	34,661	29,308
Total assets	2,353,621	1,876,969
LIABILITIES AND SHAREHOLDERS’ EQUITY
Long-term debt	311,956	212,664
Other liabilities	34,135	28,613
Total liabilities	346,091	241,277
Shareholders’ equity	2,007,530	1,635,692
Total liabilities and shareholders’ equity	$ 2,353,621	$ 1,876,969

Condensed Financial Statement_4

Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only) - Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Operations
Dividends from bank	$ 150,000	$ 0
Interest expense	56,237	83,312	$ 61,330
Income tax benefit	(45,356)	(52,991)	(49,815)
Net income	164,089	185,721	166,111
Holding Company
Statement of Operations
Dividends from bank	150,000	0	161,500
Dividends from other subsidiaries	0	4,651	850
Shared service fees from subsidiaries	13,020	14,721	10,257
Other	1,436	1,468	133
Total income	164,456	20,840	172,740
Interest expense	13,994	11,573	11,868
Other expense	16,473	18,965	14,456
Total expenses	30,467	30,538	26,324
Income tax benefit	2,681	8,711	1,640
Income (loss) before equity in undistributed earnings of subsidiaries	136,670	(987)	148,056
Equity in undistributed earnings of subsidiaries	27,419	186,708	18,055
Net income	$ 164,089	$ 185,721	$ 166,111

Condensed Financial Statement_5

Condensed Financial Statements of United Community Banks, Inc. (Holding Company Only) - Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net income	$ 164,089	$ 185,721	$ 166,111
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	7,887	9,360	6,057
Changes in assets and liabilities:
Other assets	(20,139)	(45,789)	13,195
Net cash provided by operating activities	158,681	153,933	270,006
Investing activities:
Net cash received (paid) for acquisition	195,699	(19,545)	(56,800)
Purchases of premises and equipment	(18,462)	(20,944)	(17,617)
Net cash provided by (used in) investing activities	(1,580,563)	163,218	(359,475)
Financing activities:
Proceeds from issuance of Series I preferred stock, net of issuance costs	96,422	0	0
Cash paid for shares withheld to cover payroll taxes upon vesting of restricted stock units	(3,119)	(1,686)	(1,998)
Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans	1,317	2,193	679
Proceeds from exercise of stock options	0	212	142
Repurchase of common stock	(20,782)	(13,020)	0
Cash dividends on preferred stock	(3,533)	0	0
Cash dividends on common stock	(58,912)	(53,044)	(41,634)
Net cash provided by (used in) financing activities	2,515,295	(129,210)	102,459
Net change in cash and cash equivalents, including restricted cash	1,093,413	187,941	12,990
Cash and cash equivalents, including restricted cash, at beginning of year	515,206	327,265	314,275
Cash and cash equivalents, including restricted cash, at end of year	1,608,619	515,206	327,265
Holding Company
Operating activities:
Net income	164,089	185,721	166,111
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of the subsidiaries	(27,419)	(186,708)	(18,055)
Stock-based compensation	7,887	9,360	6,057
Changes in assets and liabilities:
Other assets	(3,662)	(3,022)	1,777
Other liabilities	5,261	2,080	3,124
Net cash provided by operating activities	146,156	7,431	159,014
Investing activities:
Net cash received (paid) for acquisition	3,397	(52,093)	(84,499)
Purchases of premises and equipment	0	0	(364)
Purchases of debt securities available-for-sale and equity securities	(2,750)	(3,000)	(2,489)
Proceeds from sales and maturities of debt securities available-for-sale and equity securities	0	83	0
Net cash provided by (used in) investing activities	647	(55,010)	(87,352)
Financing activities:
Repayment of long-term debt	0	(250)	(7,424)
Proceeds from issuance of long-term debt, net of issuance costs	98,552	0	98,188
Proceeds from issuance of Series I preferred stock, net of issuance costs	96,422	0	0
Cash paid for shares withheld to cover payroll taxes upon vesting of restricted stock units	(3,119)	(1,686)	(1,998)
Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans	1,317	2,193	679
Proceeds from exercise of stock options	0	212	142
Repurchase of common stock	(20,782)	(13,020)	0
Cash dividends on preferred stock	3,533	0	0
Cash dividends on common stock	(58,912)	(53,044)	(41,634)
Net cash provided by (used in) financing activities	109,945	(65,595)	47,953
Net change in cash and cash equivalents, including restricted cash	256,748	(113,174)	119,615
Cash and cash equivalents, including restricted cash, at beginning of year	32,495	145,669	26,054
Cash and cash equivalents, including restricted cash, at end of year	$ 289,243	$ 32,495	$ 145,669

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	Feb. 18, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Cash dividend declared per common share (in dollars per share)		$ 0.72	$ 0.68	$ 0.58
Subsequent Event
Subsequent Event [Line Items]
Dividend date declared	Feb. 18, 2021
Subsequent Event | Common stock, par value $1 per share
Subsequent Event [Line Items]
Cash dividend declared per common share (in dollars per share)	$ 0.19
Dividend payable date	Apr. 5, 2021
Dividend date of record	Mar. 15, 2021
Subsequent Event | Series I perpetual non-cumulative preferred stock
Subsequent Event [Line Items]
Preferred stock dividend per preferred share (in dollars per share)	$ 429.6875
Dividend payable date	Mar. 15, 2021
Dividend date of record	Feb. 28, 2021
Subsequent Event | Depositary share on Series I perpetual non-cumulative preferred stock
Subsequent Event [Line Items]
Preferred stock dividend per preferred share (in dollars per share)	$ 0.4296875