First Busey (BUSE) 10-Q 2 Nov 23 2023 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2023	Nov. 02, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	0-15950
Entity Registrant Name	FIRST BUSEY CORPORATION
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	37-1078406
Entity Address, Address Line One	100 W. University Ave.
Entity Address, City or Town	Champaign
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	61820
City Area Code	217
Local Phone Number	365-4544
Title of 12(b) Security	Common Stock, $.001 par value
Trading Symbol	BUSE
Security Exchange Name	NASDAQ
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
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		55,258,904
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Entity Central Index Key	0000314489
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Cash and cash equivalents:
Cash and due from banks	$ 122,574	$ 117,513
Interest-bearing deposits	215,345	109,651
Total cash and cash equivalents	337,919	227,164
Debt securities available for sale	2,182,841	2,461,393
Debt securities held to maturity	882,614	918,312
Equity securities	8,782	11,535
Loans held for sale	3,051	1,253
Portfolio loans (net of ACL of $91,710 at September 30, 2023, and $91,608 at December 31, 2022)	7,764,450	7,634,094
Premises and equipment, net	122,538	126,524
Right of use assets	11,500	12,829
Goodwill	317,873	317,873
Other intangible assets, net	38,470	46,423
Cash surrender value of bank owned life insurance	181,955	180,485
Other assets	406,257	398,792
Total assets	12,258,250	12,336,677
Deposits:
Noninterest-bearing	2,918,574	3,393,666
Interest-bearing	7,413,788	6,677,614
Total deposits	10,332,362	10,071,280
Securities sold under agreements to repurchase	183,702	229,806
Short-term borrowings	12,000	351,054
Long-term debt	21,000	30,000
Subordinated notes, net of unamortized issuance costs	222,666	222,038
Junior subordinated debt owed to unconsolidated trusts	71,946	71,810
Lease liabilities	11,783	12,995
Other liabilities	212,633	201,717
Total liabilities	11,068,092	11,190,700
Outstanding commitments and contingent liabilities (see Notes 4 and 9)
Stockholders’ equity
Common stock, ($.001 par value; 100,000,000 shares authorized)	58	58
Additional paid-in capital	1,324,438	1,320,980
Retained earnings	224,698	168,769
AOCI	(290,730)	(273,278)
Total stockholders’ equity before treasury stock	1,258,464	1,216,529
Treasury stock at cost	(68,306)	(70,552)
Total stockholders’ equity	1,190,158	1,145,977
Total liabilities and stockholders’ equity	$ 12,258,250	$ 12,336,677
Shares
Common shares issued (in shares)	58,116,969	58,116,970
Less: Treasury shares (in shares)	(2,774,952)	(2,837,846)
Common shares outstanding (in shares)	55,342,017	55,279,124

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Portfolio loans, allowance for credit losses	$ 91,710	$ 91,608
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest income
Interest and fees on loans	$ 99,844	$ 76,081	$ 284,423	$ 202,530
Interest and dividends on investment securities:
Taxable interest income	20,549	17,436	60,224	47,370
Non-taxable interest income	685	813	2,136	2,482
Other interest income	1,591	1,085	3,890	1,720
Total interest income	122,669	95,415	350,673	254,102
Interest expense
Deposits	37,068	3,565	78,576	7,835
Federal funds purchased and securities sold under agreements to repurchase	1,327	459	3,772	665
Short-term borrowings	1,964	190	12,527	426
Long-term debt	425	372	1,331	859
Senior notes	0	0	0	637
Subordinated notes	3,103	3,738	9,300	9,243
Junior subordinated debt owed to unconsolidated trusts	991	786	2,849	2,148
Total interest expense	44,878	9,110	108,355	21,813
Net interest income	77,791	86,305	242,318	232,289
Provision for credit losses	364	2,364	1,944	3,764
Net interest income after provision for credit losses	77,427	83,941	240,374	228,525
Noninterest income
Mortgage revenue	311	438	871	1,697
Income on bank owned life insurance	1,001	958	3,682	2,716
Realized net gains (losses) on securities	(33)	(74)	(207)	52
Unrealized net gains (losses) recognized on equity securities	(252)	78	(2,753)	(2,376)
Other income	3,018	4,318	8,349	12,046
Total noninterest income	31,008	30,933	90,868	97,724
Noninterest expense
Salaries, wages, and employee benefits	39,677	39,762	119,867	117,226
Data processing	5,930	5,447	17,472	15,800
Net occupancy expense of premises	4,594	4,705	13,896	14,492
Furniture and equipment expenses	1,638	1,799	5,065	5,874
Professional fees	1,542	1,579	4,573	4,693
Amortization of intangible assets	2,555	2,871	7,953	8,833
Interchange expense	1,786	1,574	5,509	4,606
FDIC insurance	1,475	882	4,483	3,108
Other expense	11,748	12,117	31,735	35,572
Total noninterest expense	70,945	70,736	210,553	210,204
Income before income taxes	37,490	44,138	120,689	116,045
Income taxes	6,824	8,477	23,873	22,121
Net income	$ 30,666	$ 35,661	$ 96,816	$ 93,924
Basic earnings per common share (in dollars per share)	$ 0.55	$ 0.64	$ 1.75	$ 1.70
Diluted earnings per common share (in dollars per share)	0.54	0.64	1.72	1.67
Dividends declared per share of common stock (in dollars per share)	$ 0.24	$ 0.23	$ 0.72	$ 0.69
Wealth management fees
Noninterest income
Noninterest income	$ 14,235	$ 12,508	$ 43,594	$ 42,422
Fees for customer services
Noninterest income
Noninterest income	7,502	7,627	21,560	26,122
Payment technology solutions
Noninterest income
Noninterest income	$ 5,226	$ 5,080	$ 15,772	$ 15,045

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 30,666	$ 35,661	$ 96,816	$ 93,924
Unrealized/Unrecognized gains (losses) on debt securities:
Net unrealized holding gains (losses) on debt securities available for sale, net of taxes of $6,728, and $84,519, respectively	(26,950)	(69,306)	(16,872)	(211,988)
Net unrealized gains (losses) on debt securities transferred to held to maturity from available for sale, net of taxes of $0, and $13,812, respectively	0	0	0	(34,644)
Reclassification adjustment for realized (gains) losses on debt securities available for sale included in net income, net of taxes of $(59), and $8, respectively	24	53	148	(20)
Amortization of unrecognized losses on securities transferred to held to maturity, net of taxes of $(1,346), and $(1,396), respectively	1,056	1,291	3,379	3,500
Net change in unrealized/unrecognized gains (losses) on debt securities	(25,870)	(67,962)	(13,345)	(243,152)
Unrealized gains (losses) on cash flow hedges:
Net unrealized holding gains (losses) on cash flow hedges, net of taxes of $3,412, and $8,604, respectively	(5,577)	(10,192)	(8,563)	(21,587)
Reclassification adjustment for realized (gains) losses on cash flow hedges included in net income, net of taxes of $(1,776), and $199, respectively	1,638	266	4,456	(498)
Net change in unrealized gains (losses) on cash flow hedges	(3,939)	(9,926)	(4,107)	(22,085)
Net change in AOCI	(29,809)	(77,888)	(17,452)	(265,237)
Total comprehensive income (loss)	$ 857	$ (42,227)	$ 79,364	$ (171,313)

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent
Net unrealized holding gains (losses) on debt securities available for sale, tax expense (benefit)	$ (10,746)	$ (27,631)	$ (6,728)	$ (84,519)
Unrealized gains (losses) on debt securities transferred to held to maturity from available for sale, tax expense (benefit)	0	0	0	(13,812)
Reclassification adjustment for realized (gains) losses on debt securities available for sale included in net income, tax expense (benefit)	(9)	(21)	(59)	8
Amortization of unrealized losses on securities transferred to held to maturity, tax expense (benefit)	(420)	(515)	(1,346)	(1,396)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Net unrealized holding gains (losses) on cash flow hedges, tax expense (benefit)	(2,220)	(4,061)	(3,412)	(8,604)
Reclassification adjustment for realized (gains) losses on cash flow hedges included in net income, tax expense (benefit)	$ (652)	$ (104)	$ (1,776)	$ 199

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	AOCI	Treasury Stock
Beginning balance (in shares) at Dec. 31, 2021		55,434,910
Beginning balance, net of tax at Dec. 31, 2021	$ 1,319,112	$ 58	$ 1,316,984	$ 92,463	$ (23,758)	$ (66,635)
Increase (decrease) in shareholders' equity
Net income	93,924			93,924
OCI, net of tax	(265,237)				(265,237)
Repurchase of stock (in shares)		(388,614)
Repurchase of stock	(9,912)					(9,912)
Issuance of treasury stock for ESPP (in shares)		50,033
Issuance of treasury stock for ESPP	1,017		(271)			1,288
Net issuance of treasury stock for RSU/DSU vesting and related tax (in shares)		136,105
Net issuance of treasury stock for RSU/PSU/DSU vesting and related tax	(878)		(4,383)			3,505
Cash dividends on common stock	(38,159)			(38,159)
Stock dividend equivalents on RSUs	0		870	(870)
Stock-based compensation	6,721		6,721
Ending balance (in shares) at Sep. 30, 2022		55,232,434
Ending balance, net of tax at Sep. 30, 2022	1,106,588	$ 58	1,319,921	147,358	(288,995)	(71,754)
Beginning balance (in shares) at Jun. 30, 2022		55,335,703
Beginning balance, net of tax at Jun. 30, 2022	1,161,957	$ 58	1,317,675	124,685	(211,107)	(69,354)
Increase (decrease) in shareholders' equity
Net income	35,661			35,661
OCI, net of tax	(77,888)				(77,888)
Repurchase of stock (in shares)		(130,000)
Repurchase of stock	(3,088)					(3,088)
Issuance of treasury stock for ESPP (in shares)		10,993
Issuance of treasury stock for ESPP	206		(77)			283
Net issuance of treasury stock for RSU/DSU vesting and related tax (in shares)		15,738
Net issuance of treasury stock for RSU/PSU/DSU vesting and related tax	(29)		(434)			405
Cash dividends on common stock	(12,707)			(12,707)
Stock dividend equivalents on RSUs	0		281	(281)
Stock-based compensation	2,476		2,476
Ending balance (in shares) at Sep. 30, 2022		55,232,434
Ending balance, net of tax at Sep. 30, 2022	1,106,588	$ 58	1,319,921	147,358	(288,995)	(71,754)
Beginning balance (in shares) at Dec. 31, 2022		55,279,124
Beginning balance, net of tax at Dec. 31, 2022	1,145,977	$ 58	1,320,980	168,769	(273,278)	(70,552)
Increase (decrease) in shareholders' equity
Net income	96,816			96,816
OCI, net of tax	(17,452)				(17,452)
Repurchase of stock (in shares)		(110,123)
Repurchase of stock	(2,209)					(2,209)
Issuance of treasury stock for ESPP (in shares)		51,885
Issuance of treasury stock for ESPP	884		(451)			1,335
Net issuance of treasury stock for RSU/DSU vesting and related tax (in shares)		120,137
Net issuance of treasury stock for RSU/PSU/DSU vesting and related tax	(989)		(4,083)			3,094
Net issuance of treasury stock for warrants exercised (in shares)		994
Net issuance of treasury stock for warrants exercised	9		(17)			26
Cash dividends on common stock	(39,806)			(39,806)
Stock dividend equivalents on RSUs	0		1,081	(1,081)
Stock-based compensation	6,928		6,928
Ending balance (in shares) at Sep. 30, 2023		55,342,017
Ending balance, net of tax at Sep. 30, 2023	1,190,158	$ 58	1,324,438	224,698	(290,730)	(68,306)
Beginning balance (in shares) at Jun. 30, 2023		55,290,847
Beginning balance, net of tax at Jun. 30, 2023	1,201,948	$ 58	1,325,173	207,660	(260,921)	(70,022)
Increase (decrease) in shareholders' equity
Net income	30,666			30,666
OCI, net of tax	(29,809)				(29,809)
Repurchase of stock (in shares)		(65,123)
Repurchase of stock	(1,278)					(1,278)
Issuance of treasury stock for ESPP (in shares)		11,291
Issuance of treasury stock for ESPP	184		(106)			290
Net issuance of treasury stock for RSU/DSU vesting and related tax (in shares)		105,002
Net issuance of treasury stock for RSU/PSU/DSU vesting and related tax	(889)		(3,593)			2,704
Cash dividends on common stock	(13,267)			(13,267)
Stock dividend equivalents on RSUs	0		361	(361)
Stock-based compensation	2,603		2,603
Ending balance (in shares) at Sep. 30, 2023		55,342,017
Ending balance, net of tax at Sep. 30, 2023	$ 1,190,158	$ 58	$ 1,324,438	$ 224,698	$ (290,730)	$ (68,306)

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Stockholders' Equity [Abstract]
Cash dividends, common stock (in dollars per share)	$ 0.24	$ 0.23	$ 0.72	$ 0.69
Stock dividends, restricted stock units (in dollars per share)		$ 0.23		$ 0.69

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows provided by (used in) operating activities
Net income	$ 96,816	$ 93,924
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for credit losses	1,944	3,764
Amortization of intangible assets	7,953	8,833
Amortization of mortgage servicing rights	2,155	2,757
Amortization of NMTC	6,740	4,668
Depreciation and amortization of premises and equipment	7,052	8,035
Net amortization (accretion) on portfolio loans	5,399	2,524
Net amortization (accretion) of premium (discount) on investment securities	11,351	15,820
Net amortization (accretion) of premium (discount) on time deposits	(223)	(318)
Net amortization (accretion) of premium (discount) on FHLB advances and other borrowings	764	1,152
Impairment of OREO and other repossessed assets	113	611
Impairment of fixed assets held for sale	0	427
Impairment of mortgage servicing rights	1	(9)
Impairment of leases	0	84
Unrealized (gains) losses recognized on equity securities, net	2,753	2,376
(Gain) loss on sales of equity securities, net	0	(24)
(Gain) loss on sales of debt securities, net	207	(28)
(Gain) loss on sales of loans, net	(603)	(1,777)
(Gain) loss on sales of OREO	4	56
(Gain) loss on sales of premises and equipment	(197)	(666)
(Gain) loss on life insurance proceeds	(759)	0
(Increase) decrease in cash surrender value of bank owned life insurance	(2,923)	(2,716)
Provision for deferred income taxes	(2,000)	(3)
Stock-based compensation	6,928	6,721
Mortgage loans originated for sale	(28,663)	(63,986)
Proceeds from sales of mortgage loans	27,418	84,732
(Increase) decrease in other assets	(15,072)	(45,575)
Increase (decrease) in other liabilities	171	(3,364)
Net cash provided by (used in) operating activities	127,329	118,018
Cash flows provided by (used in) investing activities
Purchases of equity securities	(6,169)	(14,820)
Purchases of debt securities available for sale	(7,796)	(279,831)
Proceeds from sales of equity securities	6,169	15,418
Proceeds from paydowns and maturities of debt securities held to maturity	38,172	51,552
Proceeds from paydowns and maturities of debt securities available for sale	253,648	370,274
Purchases of FHLB and other bank stock	(30,957)	0
Proceeds from the redemption of FHLB and other bank stock	43,926	225
Net (increase) decrease in loans	(137,843)	(484,701)
Cash paid for premiums on bank-owned life insurance	(80)	(101)
Proceeds from life insurance	2,292	219
Purchases of premises and equipment	(6,750)	(4,006)
Proceeds from disposition of premises and equipment	3,881	4,182
Proceeds from sales of OREO	781	2,662
Net cash provided by (used in) investing activities	159,274	(338,927)
Cash flows provided by (used in) financing activities
Net increase (decrease) in deposits	261,305	(166,862)
Net change in federal funds purchased and securities sold under agreements to repurchase	(46,104)	(35,542)
Proceeds from FHLB advances	265,000	0
Repayment of FHLB advances	(604,054)	(5,507)
Proceeds from other borrowings, net of debt issuance costs	0	98,094
Repayment of other borrowings	(9,000)	(109,000)
Cash dividends paid	(39,806)	(38,159)
Purchase of treasury stock	(2,209)	(9,912)
Cash paid for withholding taxes on stock-based payments	(989)	(878)
Proceeds from stock warrants exercised	9	0
Issuance of treasury stock for ESPP	0	(271)
Net cash provided by (used in) financing activities	(175,848)	(268,037)
Net increase (decrease) in cash and cash equivalents	110,755	(488,946)
Cash and cash equivalents, beginning of period	227,164	836,095
Cash and cash equivalents, ending of period	337,919	347,149
Cash payments for:
Interest	89,572	19,465
Income taxes	23,594	30,506
Non-cash investing and financing activities:
OREO acquired in settlement of loans	144	132
Transfer of debt securities available for sale to held to maturity	$ 0	$ 985,199

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Nature of Operations First Busey Corporation, a Nevada corporation organized in 1980, is a $12.3 billion financial holding company headquartered in Champaign, Illinois. Busey’s common stock is traded on The Nasdaq Global Select Market under the symbol “BUSE.” First Busey operates and reports its business in three segments: Banking, Wealth Management, and FirsTech. • The Banking operating segment provides a full range of banking services to individual and corporate customers through its banking center network in Illinois; the St. Louis, Missouri metropolitan area; southwest Florida; and Indianapolis, Indiana. • The Wealth Management operating segment provides a full range of asset management, investment, brokerage, fiduciary, philanthropic advisory, tax preparation, and farm management services to individuals, businesses, and foundations. • The FirsTech operating segment provides comprehensive and innovative payment technology solutions including online, mobile, and voice-recognition bill payments; money management and credit card networks; direct debit services; lockbox remittance processing for payments made by mail; and walk-in payments. FirsTech also provides additional tools to help clients with billing, reconciliation, bill reminders, and treasury services. For additional information about First Busey's operating segments, see “ Note 14. Operating Segments and Related Information .” Basis of Financial Statement Presentation These unaudited consolidated financial statements and related notes should be read in conjunction with the audited consolidated financial statements included in Busey's 2022 Annual Report . These interim unaudited consolidated financial statements serve to update our 2022 Annual Report and may not include all information and notes necessary to constitute a complete set of financial statements. We prepared these unaudited consolidated financial statements in conformity with GAAP. We have eliminated intercompany accounts and transactions. We have also reclassified certain prior year amounts to conform to the current period presentation. These reclassifications did not have a material impact on our consolidated financial condition or results of operations. In our opinion, the unaudited consolidated financial statements reflect all normal, recurring adjustments needed to present fairly our results for the interim periods. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the full year or any other interim period. Use of Estimates In preparing the accompanying unaudited consolidated financial statements in conformity with GAAP, Busey’s management is required to make estimates and assumptions that affect the amounts reported in the financial statements and the disclosures provided. Actual results could differ from those estimates. Material estimates which are particularly susceptible to significant change in the near term relate to the fair value of debt securities available for sale, fair value of assets acquired and liabilities assumed in business combinations, goodwill, income taxes, and the determination of the ACL. Impact of Recently Adopted Accounting Standards In July 2023, the FASB issued ASU 2023-03 “Presentation of Financial Statements (Topic 205), Income Statement—Reporting Comprehensive Income (Topic 220), Distinguishing Liabilities from Equity (Topic 480), Equity (Topic 505), and Compensation—Stock Compensation (Topic 718)” pursuant to: (i) SEC Staff Accounting Bulletin No. 120, which provided interpretive guidance related to estimating the fair value of share-based payment transactions while in possession of material non-public information; (ii) an SEC Staff Announcement at the March 24, 2022, Emerging Issues Task Force Meeting, which provided interpretive guidance on accounting for share-based payments to employees and non-employees; and (iii) Staff Accounting Bulletin Topic 6.B, Accounting Series Release 280—General Revision of Regulation S-X: Income or Loss Applicable to Common Stock, which provided interpretive guidance on the reporting of income or loss applicable to common stock. This update was reflected in the Accounting Standards Codification upon issuance. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. In March 2022, the FASB issued ASU 2022-02 “Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures,” which eliminates the TDR accounting model for creditors that have already adopted CECL. In lieu of the TDR accounting model, loan refinancing and restructuring guidance in ASC Subtopic 310-20-35-9 through 35-11 “Receivables—Nonrefundable Fees and Other Costs—Subsequent Measurement—Loan Refinancing or Restructuring” will apply to all loan modifications, including those made for borrowers experiencing financial difficulty. This standard also enhances disclosure requirements related to certain loan modifications. Additionally, this standard introduces new requirements to disclose gross write-off information in the vintage disclosures of financing receivables by credit quality indicator and class of financing receivable by year of origination. This standard applies prospectively. For the transition method related to the recognition and measurement of TDRs, there is an option to apply a modified retrospective transition method, resulting in a cumulative-effect adjustment to retained earnings in the period of adoption. This standard became effective for Busey beginning January 1, 2023. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. In March 2022, the FASB issued ASU 2022-01 “Derivatives and Hedging (Topic 815): Fair Value Hedging—Portfolio Layer Method,” which replaces the current last-of-layer hedge accounting method with an expanded portfolio layer method that permits multiple hedged layers of a single closed portfolio. The scope of the portfolio layer method is also expanded to include non-prepayable financial assets. This update also provides additional guidance on the accounting for and disclosure of hedge basis adjustments that are applicable to the portfolio layer method, and specifies how hedge basis adjustments should be considered when determining credit losses for the assets included in the closed portfolio. Amendments related to hedge basis adjustments which are included in this standard apply on a modified retrospective basis by means of a cumulative-effect adjustment to the opening balance of retained earnings on the initial application date. Amendments related to disclosure which are included in this standard may be applied on a prospective basis from the initial application date, or on a retrospective basis to each prior period presented after the date of adoption of the amendments in ASU 2017-12 “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.” This standard became effective for Busey beginning January 1, 2023. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. ASU 2021-08 “Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers” requires measurement and recognition in accordance with ASC Topic 606 “Revenue from Contracts with Customers” for contract assets and contract liabilities acquired in a business combination. This update became effective for Busey beginning January 1, 2023. This standard applied prospectively to all business combinations that occurred on or after the date of adoption. Adoption of this standard did not have an impact on Busey’s financial position or results of operations. Recently Issued Accounting Standards Not Yet Adopted In March 2023, the FASB issued ASU 2023-02 “Investments—Equity Method and Joint Ventures (Topic 323),” permitting an election to use the proportional amortization method to account for equity investments made primarily for the purpose of receiving income tax credits and other income tax benefits, regardless of the tax credit program from which the income tax credits are received, provided that certain conditions are met. The proportional amortization method results in the cost of the investment being amortized in proportion to the income tax credits and other income tax benefits received, with the amortization of the investment and the income tax credits being presented net in the income statement as a component of income tax expense. This standard must be applied on a retrospective or modified retrospective basis, and is applicable for Busey beginning on January 1, 2024. Early adoption is permitted. Busey is currently evaluating the potential effect on the Company’s financial position and results of operations, and upon adoption expects changes to be reflected in the Other Expense and Income Taxes line items in the Consolidated Statements of Income (Unaudited). In March 2023, the FASB issued ASU 2023-01 “Leases (Topic 842): Common Control Arrangements,” which requires amortization over the useful life of leasehold improvements (not the lease term) when the lease is between entities under common control, and any value of such leasehold improvements remaining at the end of the lease term is to be accounted for as a transfer between entities under common control. This standard may be adopted either prospectively, or retrospectively, and is effective for Busey beginning January 1, 2024. Early adoption is permitted. Busey does not expect adoption of this standard to have a material impact on the Company’s financial position and results of operations. In June 2022, the FASB issued ASU 2022-03 “Fair Value Measurements (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions,” which clarifies that contractual restrictions on the sale of equity securities are not considered in measuring the fair value of those equity securities, and further that contractual sale restrictions cannot be recognized and measured as a separate unit of account. This standard applies prospectively, and is effective for Busey beginning January 1, 2024. Early adoption is permitted. Busey is currently evaluating the potential effect on the Company’s financial position and results of operations. Subsequent Events Busey has evaluated subsequent events for potential recognition and/or disclosure through the date the unaudited consolidated financial statements included in this Quarterly Report were issued. The Company issued a Form 8‑K on October 24, 2023 , regarding the departure of a named executive officer, and during the fourth quarter of 2023 expects to record related severance expenses according to Schedule 1 of the Separation Letter that was filed as Exhibit 10.1 to the Form 8‑K . Other than this, there were no significant subsequent events for the quarter ended September 30, 2023, through the filing date of these unaudited consolidated financial statements.

Debt Securities

Debt Securities	9 Months Ended
	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Debt Securities	Debt Securities Busey's portfolio of debt securities includes both available for sale and held to maturity securities. The tables below provide the amortized cost, unrealized gains and losses, and fair values of debt securities summarized by major category (dollars in thousands) : As of September 30, 2023 Amortized Unrealized Fair Gross Gains Gross Losses Debt securities available for sale U.S. Treasury securities $ 51,522 $ — $ (1,392) $ 50,130 Obligations of U.S. government corporations and agencies 10,071 2 (254) 9,819 Obligations of states and political subdivisions 1 254,549 6 (27,758) 226,797 Asset-backed securities 486,517 — (7,069) 479,448 Commercial mortgage-backed securities 120,117 — (19,817) 100,300 Residential mortgage-backed securities 2 1,343,324 — (254,528) 1,088,796 Corporate debt securities 251,194 91 (23,734) 227,551 Total debt securities available for sale $ 2,517,294 $ 99 $ (334,552) $ 2,182,841 ___________________________________________ 1. Includes securities marked at par, with no gain or loss to report. 2. Gross gains on Residential mortgage-backed securities were insignificant, rounding to zero thousand. Amortized Unrecognized Fair Gross Gains Gross Losses Debt securities held to maturity Commercial mortgage-backed securities $ 459,866 $ — $ (93,401) $ 366,465 Residential mortgage-backed securities 422,748 — (87,537) 335,211 Total debt securities held to maturity $ 882,614 $ — $ (180,938) $ 701,676 As of December 31, 2022 Amortized Unrealized Fair Gross Gains Gross Losses Debt securities available for sale U.S. Treasury securities $ 117,805 $ — $ (3,744) $ 114,061 Obligations of U.S. government corporations and agencies 20,097 3 (321) 19,779 Obligations of states and political subdivisions 283,481 106 (26,075) 257,512 Asset-backed securities 489,558 — (19,683) 469,875 Commercial mortgage-backed securities 124,423 — (16,029) 108,394 Residential mortgage-backed securities 1,463,971 2 (220,717) 1,243,256 Corporate debt securities 273,118 33 (24,635) 248,516 Total debt securities available for sale $ 2,772,453 $ 144 $ (311,204) $ 2,461,393 Amortized Unrecognized Fair Gross Gains Gross Losses Debt securities held to maturity Commercial mortgage-backed securities $ 474,820 $ — $ (63,738) $ 411,082 Residential mortgage-backed securities 443,492 — (69,279) 374,213 Total debt securities held to maturity $ 918,312 $ — $ (133,017) $ 785,295 Maturities of Debt Securities Amortized cost and fair value of debt securities, by contractual maturity or pre-refunded date, are shown below. Mortgages underlying mortgage-backed securities and asset-backed securities may be called or prepaid; therefore, actual maturities could differ from the contractual maturities. All mortgage-backed securities were issued by U.S. government corporations and agencies (dollars in thousands) : As of September 30, 2023 Amortized Fair Debt securities available for sale Due in one year or less $ 109,189 $ 106,940 Due after one year through five years 312,419 289,027 Due after five years through ten years 431,297 389,702 Due after ten years 1,664,389 1,397,172 Debt securities available for sale $ 2,517,294 $ 2,182,841 Debt securities held to maturity Due after one year through five years $ 63,474 $ 58,144 Due after five years through ten years 40,076 34,985 Due after ten years 779,064 608,547 Debt securities held to maturity $ 882,614 $ 701,676 Gains and Losses on Debt Securities Available for Sale Realized gains and losses related to sales and calls of debt securities available for sale are summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Realized gains and losses on debt securities Gross gains on debt securities $ 10 $ — $ 20 $ 114 Gross (losses) on debt securities (43) (74) (227) (86) Realized net gains (losses) on debt securities 1 $ (33) $ (74) $ (207) $ 28 ___________________________________________ 1. Net gains (losses) on sales of securities reported in the Consolidated Statements of Income (Unaudited) include sales of equity securities, excluded in this table. Debt securities with carrying amounts of $819.8 million on September 30, 2023, and $746.7 million on December 31, 2022, were pledged as collateral for public deposits, securities sold under agreements to repurchase, and for other purposes as required. Debt Securities in an Unrealized or Unrecognized Loss Position The following information pertains to debt securities with gross unrealized or unrecognized losses, aggregated by investment category and the length of time that individual securities have been in a continuous loss position (dollars in thousands) : As of September 30, 2023 Less than 12 months 12 months or more Total Fair Unrealized Fair Unrealized Fair Unrealized Debt securities available for sale U.S. Treasury securities $ — $ — $ 50,130 $ (1,392) $ 50,130 $ (1,392) Obligations of U.S. government corporations and agencies 1,983 (6) 7,699 (248) 9,682 (254) Obligations of states and political subdivisions 45,778 (1,219) 177,195 (26,539) 222,973 (27,758) Asset-backed securities — — 479,448 (7,069) 479,448 (7,069) Commercial mortgage-backed securities — — 100,300 (19,817) 100,300 (19,817) Residential mortgage-backed securities 431 (10) 1,088,344 (254,518) 1,088,775 (254,528) Corporate debt securities 1,457 (2) 219,074 (23,732) 220,531 (23,734) Debt securities available for sale with gross unrealized losses $ 49,649 $ (1,237) $ 2,122,190 $ (333,315) $ 2,171,839 $ (334,552) 12 months or more Total Fair Unrecognized Fair Unrecognized Debt securities held to maturity Commercial mortgage-backed securities $ 366,465 $ (93,401) $ 366,465 $ (93,401) Residential mortgage-backed securities 335,211 (87,537) 335,211 (87,537) Debt securities held to maturity with gross unrecognized losses $ 701,676 $ (180,938) $ 701,676 $ (180,938) As of December 31, 2022 Less than 12 months 12 months or more Total Fair Unrealized Fair Unrealized Fair Unrealized Debt securities available for sale U.S. Treasury securities 1 $ 74 $ — $ 113,987 $ (3,744) $ 114,061 $ (3,744) Obligations of U.S. government corporations and agencies 19,603 (321) — — 19,603 (321) Obligations of states and political subdivisions 166,147 (10,059) 75,217 (16,016) 241,364 (26,075) Asset-backed securities 390,164 (15,648) 79,711 (4,035) 469,875 (19,683) Commercial mortgage-backed securities 89,428 (12,623) 18,966 (3,406) 108,394 (16,029) Residential mortgage-backed securities 366,221 (38,111) 876,668 (182,606) 1,242,889 (220,717) Corporate debt securities 39,037 (5,079) 204,310 (19,556) 243,347 (24,635) Debt securities available for sale with gross unrealized losses $ 1,070,674 $ (81,841) $ 1,368,859 $ (229,363) $ 2,439,533 $ (311,204) Less than 12 months 12 months or more Total Fair Unrecognized Fair Unrecognized Fair Unrecognized Debt securities held to maturity Commercial mortgage-backed securities $ 58,065 $ (8,009) $ 353,017 $ (55,729) $ 411,082 $ (63,738) Residential mortgage-backed securities — — 374,213 (69,279) 374,213 (69,279) Debt securities held to maturity with gross unrecognized losses $ 58,065 $ (8,009) $ 727,230 $ (125,008) $ 785,295 $ (133,017) ___________________________________________ 1. Unrealized losses for U.S. Treasury securities that had been in a continuous unrealized loss position for less than 12 months were insignificant, rounding to zero thousand. Additional information about debt securities in an unrealized or unrecognized loss position is presented in the tables below (dollars in thousands) : As of September 30, 2023 Available for Sale Held to Maturity Total Debt securities with gross unrealized or unrecognized losses, fair value $ 2,171,839 $ 701,676 $ 2,873,515 Gross unrealized or unrecognized losses on debt securities 334,552 180,938 515,490 Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses 15.4 % 25.8 % 17.9 % Count of debt securities 1,001 55 1,056 Count of debt securities in an unrealized or unrecognized loss position 982 55 1,037 As of December 31, 2022 Available for Sale Held to Maturity Total Debt securities with gross unrealized or unrecognized losses, fair value $ 2,439,533 $ 785,295 $ 3,224,828 Gross unrealized or unrecognized losses on debt securities 311,204 133,017 444,221 Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses 12.8 % 16.9 % 13.8 % Count of debt securities 1,091 55 1,146 Count of debt securities in an unrealized or unrecognized loss position 1,032 55 1,087 Unrealized and unrecognized losses were related to changes in market interest rates and market conditions that do not represent credit-related impairments. Busey does not intend to sell securities that are in an unrealized or unrecognized loss position, and it is more likely than not that the Company will recover the amortized cost prior to being required to sell the debt securities. Full collection of the amounts due according to the contractual terms of the debt securities is expected; therefore, no ACL was recorded in relation to debt securities, and the impairment related to noncredit factors on debt securities available for sale is recognized in AOCI, net of applicable taxes. As of September 30, 2023, Busey did not hold general obligation bonds of any single issuer, the aggregate of which exceeded 10% of the Company’s stockholders’ equity.

Portfolio Loans

Portfolio Loans	9 Months Ended
	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Portfolio Loans	Portfolio Loans Loan Categories Busey’s lending can be summarized in two primary categories: commercial and retail. Lending is further classified into five primary areas of loans: commercial loans, commercial real estate loans, real estate construction loans, retail real estate loans, and retail other loans. Distributions of the loan portfolio by loan category and class is presented in the following table (dollars in thousands) : As of September 30, December 31, Commercial loans Commercial $ 1,943,449 $ 1,974,154 Commercial real estate 3,353,753 3,261,873 Real estate construction 527,598 530,469 Total commercial loans 5,824,800 5,766,496 Retail loans Retail real estate 1,715,445 1,657,082 Retail other 315,915 302,124 Total retail loans 2,031,360 1,959,206 Total portfolio loans 7,856,160 7,725,702 ACL (91,710) (91,608) Portfolio loans, net $ 7,764,450 $ 7,634,094 Net deferred loan origination costs included in the balances above were $13.4 million as of September 30, 2023, compared to $14.0 million as of December 31, 2022. Net accretable purchase accounting adjustments included in the balances above reduced loans by $4.9 million as of September 30, 2023, and $5.9 million as of December 31, 2022. Commercial balances include loans originated under the PPP with an amortized cost of $0.6 million as of September 30, 2023, and $0.8 million as of December 31, 2022. Busey did not purchase any retail real estate loans during the three or nine months ended September 30, 2023, or 2022. Pledged Loans Busey had loans pledged to the FHLB and Federal Reserve for liquidity as set forth in the table below (dollars in thousands) : As of September 30, December 31, Pledged loans FHLB $ 4,852,634 $ 5,095,448 Federal Reserve Bank 858,312 804,718 Total pledged loans $ 5,710,946 $ 5,900,166 Risk Grading Busey utilizes a loan grading scale to assign a risk grade to all of its loans. A description of the general characteristics of each grade is as follows: • Pass – This category includes loans that are all considered acceptable credits, ranging from investment or near investment grade, to loans made to borrowers who exhibit credit fundamentals that meet or exceed industry standards. • Watch – This category includes loans that warrant a higher-than-average level of monitoring to ensure that weaknesses do not cause the inability of the credit to perform as expected. These loans are not necessarily a problem due to other inherent strengths of the credit, such as guarantor strength, but have above average concern and monitoring. • Special mention – This category is for “Other Assets Specially Mentioned” loans that have potential weaknesses, which may, if not checked or corrected, weaken the asset or inadequately protect the Company’s credit position at some future date. • Substandard – This category includes “Substandard” loans, determined in accordance with regulatory guidelines, for which the accrual of interest has not been stopped. Assets so classified must have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. • Substandard non-accrual – This category includes loans that have all the characteristics of a “Substandard” loan with additional factors that make collection in full highly questionable and improbable. Such loans are placed on non-accrual status and may be dependent on collateral with a value that is difficult to determine. All loans are graded at their inception. Commercial lending relationships that are $1.0 million or less are usually processed through an expedited underwriting process. Most commercial loans greater than $1.0 million are included in a portfolio review at least annually. Commercial loans greater than $0.35 million that have a grading of special mention or worse are typically reviewed on a quarterly basis. Interim reviews may take place if circumstances of the borrower warrant a more frequent review. The following table is a summary of risk grades segregated by category and class of portfolio loans (dollars in thousands) : As of September 30, 2023 Pass Watch Special Substandard Substandard Total Commercial loans Commercial $ 1,533,562 $ 350,820 $ 24,705 $ 28,734 $ 5,628 $ 1,943,449 Commercial real estate 2,944,191 351,494 44,771 11,739 1,558 3,353,753 Real estate construction 513,218 9,027 — 5,353 — 527,598 Total commercial loans 4,990,971 711,341 69,476 45,826 7,186 5,824,800 Retail loans Retail real estate 1,698,692 10,245 642 1,824 4,042 1,715,445 Retail other 315,845 — — — 70 315,915 Total retail loans 2,014,537 10,245 642 1,824 4,112 2,031,360 Total portfolio loans $ 7,005,508 $ 721,586 $ 70,118 $ 47,650 $ 11,298 $ 7,856,160 As of December 31, 2022 Pass Watch Special Substandard Substandard Total Commercial loans Commercial $ 1,668,495 $ 201,758 $ 46,540 $ 51,187 $ 6,174 $ 1,974,154 Commercial real estate 2,851,709 326,455 43,526 34,539 5,644 3,261,873 Real estate construction 502,904 25,164 1 2,400 — 530,469 Total commercial loans 5,023,108 553,377 90,067 88,126 11,818 5,766,496 Retail loans Retail real estate 1,639,599 10,520 1,338 2,529 3,096 1,657,082 Retail other 301,971 — — — 153 302,124 Total retail loans 1,941,570 10,520 1,338 2,529 3,249 1,959,206 Total portfolio loans $ 6,964,678 $ 563,897 $ 91,405 $ 90,655 $ 15,067 $ 7,725,702 Risk grades of portfolio loans and net charge-offs are presented in the tables below by loan class, further sorted by origination year (dollars in thousands) : As of and For The Nine Months Ended September 30, 2023 Term Loans Amortized Cost Basis by Origination Year Revolving Total Risk Grade Ratings 2023 2022 2021 2020 2019 Prior Commercial Pass $ 279,467 $ 255,619 $ 181,603 $ 74,600 $ 39,483 $ 152,523 $ 550,267 $ 1,533,562 Watch 112,285 59,685 44,244 25,119 7,526 24,532 77,429 350,820 Special Mention 616 541 651 1,104 499 6,937 14,357 24,705 Substandard 8,901 912 1,119 445 3,948 1,859 11,550 28,734 Substandard non-accrual 583 — 2,605 103 130 507 1,700 5,628 Total commercial 401,852 316,757 230,222 101,371 51,586 186,358 655,303 1,943,449 Current period charge-offs — — 420 — 316 997 — 1,733 Commercial real estate Pass 352,661 850,371 778,662 404,109 281,889 258,207 18,292 2,944,191 Watch 82,748 45,945 69,450 33,694 79,906 34,700 5,051 351,494 Special Mention 18,753 1,597 13,762 3,908 3,330 3,421 — 44,771 Substandard 1,882 193 904 2,987 1,831 3,898 44 11,739 Substandard non-accrual 225 533 165 25 — 610 — 1,558 Total commercial real estate 456,269 898,639 862,943 444,723 366,956 300,836 23,387 3,353,753 Current period charge-offs — — — — 239 936 — 1,175 Real estate construction Pass 152,897 171,900 104,963 54,943 1,365 3,899 23,251 513,218 Watch 1,065 4,453 253 3,214 42 — — 9,027 Substandard 5,353 — — — — — — 5,353 Total real estate construction 159,315 176,353 105,216 58,157 1,407 3,899 23,251 527,598 Retail real estate Pass 201,140 379,512 420,164 162,295 71,102 274,617 189,862 1,698,692 Watch 767 2,704 2,877 973 579 596 1,749 10,245 Special Mention 204 55 — — — 383 — 642 Substandard 73 73 295 53 82 1,010 238 1,824 Substandard non-accrual — 538 56 187 101 2,434 726 4,042 Total retail real estate 202,184 382,882 423,392 163,508 71,864 279,040 192,575 1,715,445 Current period charge-offs — 5 — 29 62 156 — 252 Retail other Pass 86,096 102,834 25,977 8,172 6,388 1,539 84,839 315,845 Substandard non-accrual — 63 — 3 3 1 — 70 Total retail other 86,096 102,897 25,977 8,175 6,391 1,540 84,839 315,915 Current period charge-offs 4 71 157 1 — 250 — 483 Total portfolio loans $ 1,305,716 $ 1,877,528 $ 1,647,750 $ 775,934 $ 498,204 $ 771,673 $ 979,355 $ 7,856,160 Total current period charge-offs $ 4 $ 76 $ 577 $ 30 $ 617 $ 2,339 $ — $ 3,643 As of December 31, 2022 Term Loans Amortized Cost Basis by Origination Year Revolving Total Risk Grade Ratings 2022 2021 2020 2019 2018 Prior Commercial Pass $ 479,893 $ 266,122 $ 136,445 $ 52,046 $ 50,764 $ 135,000 $ 548,225 $ 1,668,495 Watch 54,195 49,382 3,288 7,201 1,258 2,160 84,274 201,758 Special Mention 1,958 937 1,642 974 1,000 17,024 23,005 46,540 Substandard 8,926 1,165 570 6,671 2,382 5,191 26,282 51,187 Substandard non-accrual 21 3,292 226 135 — 100 2,400 6,174 Total commercial 544,993 320,898 142,171 67,027 55,404 159,475 684,186 1,974,154 Commercial real estate Pass 883,688 819,133 478,452 297,525 161,409 198,419 13,083 2,851,709 Watch 77,346 56,113 64,282 96,664 21,592 5,758 4,700 326,455 Special Mention 11,943 5,389 12,386 1,420 6,917 5,471 — 43,526 Substandard 5,340 13,528 3,454 1,907 10,248 62 — 34,539 Substandard non-accrual — 3,959 33 — 1,647 5 — 5,644 Total commercial real estate 978,317 898,122 558,607 397,516 201,813 209,715 17,783 3,261,873 Real estate construction Pass 219,112 191,724 68,015 1,490 1,901 1,751 18,911 502,904 Watch 8,530 12,019 3,169 48 — 1,398 — 25,164 Special Mention — — — 1 — — — 1 Substandard 2,400 — — — — — — 2,400 Total real estate construction 230,042 203,743 71,184 1,539 1,901 3,149 18,911 530,469 Retail real estate Pass 396,547 456,158 175,148 77,569 56,887 267,387 209,903 1,639,599 Watch 2,928 2,991 1,846 1,444 1,063 27 221 10,520 Special Mention 945 — — — — 393 — 1,338 Substandard 77 732 198 81 141 1,293 7 2,529 Substandard non-accrual 10 191 107 32 390 1,708 658 3,096 Total retail real estate 400,507 460,072 177,299 79,126 58,481 270,808 210,789 1,657,082 Retail other Pass 134,567 43,512 13,141 13,086 5,646 991 91,028 301,971 Substandard non-accrual 14 134 3 — — 2 — 153 Total retail other 134,581 43,646 13,144 13,086 5,646 993 91,028 302,124 Total portfolio loans $ 2,288,440 $ 1,926,481 $ 962,405 $ 558,294 $ 323,245 $ 644,140 $ 1,022,697 $ 7,725,702 Past Due and Non-accrual Loans An analysis of the amortized cost basis of portfolio loans that are past due and still accruing, or on a non-accrual status, is as follows (dollars in thousands) : As of September 30, 2023 Loans past due, still accruing Non-accrual 30-59 Days 60-89 Days 90+Days Past due and non-accrual loans Commercial loans: Commercial $ — $ 112 $ 51 $ 5,628 Commercial real estate — 109 — 1,558 Real estate construction — 244 — — Past due and non-accrual commercial loans — 465 51 7,186 Retail loans: Retail real estate 3,643 840 558 4,042 Retail other 914 72 100 70 Past due and non-accrual retail loans 4,557 912 658 4,112 Total past due and non-accrual loans $ 4,557 $ 1,377 $ 709 $ 11,298 As of December 31, 2022 Loans past due, still accruing Non-accrual 30-59 Days 60-89 Days 90+Days Past due and non-accrual loans Commercial loans: Commercial $ 2 $ — $ — $ 6,174 Commercial real estate 124 — — 5,644 Past due and non-accrual commercial loans 126 — — 11,818 Retail loans: Retail real estate 4,709 1,239 673 3,096 Retail other 414 60 — 153 Past due and non-accrual retail loans 5,123 1,299 673 3,249 Total past due and non-accrual loans $ 5,249 $ 1,299 $ 673 $ 15,067 Gross interest income recorded on 90+ days past due loans, and that would have been recorded on non-accrual loans if they had been accruing interest in accordance with their original terms, was $0.2 million and $0.9 million for the three and nine months ended September 30, 2023, respectively, and was $0.3 million and $0.8 million for the three and nine months ended September 30, 2022, respectively. The amount of interest collected on those loans and recognized on a cash basis that was included in interest income was insignificant for the three and nine months ended September 30, 2023. Interest collected on these loans and recognized on a cash basis was insignificant for the three months ended September 30, 2022, and was $0.4 million for the nine months ended September 30, 2022. Loan Modification Disclosures Pursuant to ASU 2022-02 The following tables show the amortized cost basis of loans that were modified for borrowers experiencing financial difficulty during the periods indicated, disaggregated by class of financing receivable and type of concession granted (dollars in thousands) : Three Months Ended September 30, 2023 Interest Rate Reduction 1 % of Total Class of Financing Receivable 2 Term Extension 3 % of Total Class of Financing Receivable 2 Loan class: Commercial $ — — % $ 12,026 0.6 % Commercial real estate 880 — % 553 — % Total of loans modified during the period 4 $ 880 — % $ 12,579 0.2 % ___________________________________________ 1. For one loan, the default rate was removed once forbearance was entered. 2. Modified loans represent an insignificant portion of commercial real estate loans, rounding to zero percent. 3. Modifications to extend loan terms also included, in some cases, interest rate increases during the extension period. 4. All modifications were for loans classified as substandard. Nine Months Ended September 30, 2023 Interest Rate Reduction 1 % of Total Class of Financing Receivable 2 Payment Deferral 3 % of Total Class of Financing Receivable 2 Term Extension 4 % of Total Class of Financing Receivable 2 Loan class: Commercial $ — — % $ — — % $ 17,334 0.9 % Commercial real estate 880 — % 225 — % 1,003 — % Real estate construction — — % — — % 5,353 1.0 % Total of loans modified during the period 5 $ 880 — % $ 225 — % $ 23,690 0.3 % ___________________________________________ 1. For one loan, the default rate was removed once forbearance was entered. 2. Modified loans represent an insignificant portion of commercial real estate loans, rounding to zero percent. 3. A loan with payment deferral was modified to defer all principal payments until the end of the loan term, which was shortened. 4. Modifications to extend loan terms also included, in some cases, interest rate increases during the extension period. 5. Modifications include two loans on non-accrual status, and the remaining loans were classified as substandard. The following table summarizes the effects of loan modifications made during the periods indicated, for borrowers experiencing financial difficulty: Three Months Ended September 30, 2023 Nine Months Ended September 30, 2023 Weighted Average Interest Rate Reduction Weighted Average Term Extension Weighted Average Interest Rate Reduction Weighted Average Term Extension Loan class: Commercial 15.3 months 14.3 months Commercial real estate 2.50 % 9.0 months 2.50 % 11.2 months Real estate construction 12.0 months Total financial effect 2.50 % 15.0 months 2.50 % 13.7 months No financing receivables had payment defaults during the three months ended September 30, 2023, after having been modified during the 12 months before default for borrowers experiencing financial difficulty. The following table provides the amortized cost basis of financing receivables that had a payment default during the nine months ended September 30, 2023, after having been modified during the 12 months before default for borrowers experiencing financial difficulty (dollars in thousands) . A default occurs when a loan is 90 days or more past due or transferred to non-accrual status. Nine Months Ended September 30, 2023 Payment Deferral Term Extension Loan class: Commercial $ — $ 500 Commercial real estate 225 — Amortized cost of modified loans with subsequent defaults $ 225 $ 500 Busey closely monitors the performance of the loans that are modified to borrowers experiencing financial difficulty to understand the effectiveness of its modification efforts. The following table depicts the payment performance of loans modified on or after January 1, 2023, the date we adopted ASU 2022-02 (dollars in thousands) : As of September 30, 2023 Current Non-accrual Loan class: Commercial $ 16,834 $ 500 Commercial real estate 1,883 225 Real estate construction 5,353 — Amortized cost of modified loans $ 24,070 $ 725 TDR Disclosures Prior to the Adoption of ASU 2022-02 At December 31, 2022, performing TDR’s were $3.0 million and non-performing TDR’s were $0.5 million. No loans were newly designated as a TDR during the three months ended September 30, 2022, and one loan was newly designated as a TDR during the nine months ended September 30, 2022. There were no TDRs entered into during the 12 months ended September 30, 2022, that had subsequent defaults during the three or nine months ended September 30, 2022. Gross interest income that would have been recorded in the three and nine months ended September 30, 2022, if TDRs had performed in accordance with their original terms compared with their modified terms, was insignificant. Collateral Dependent Loans Management's evaluation as to the ultimate collectability of loans includes estimates regarding future cash flows from operations and the value of property, real and personal, pledged as collateral. These estimates are affected by changing economic conditions and the economic prospects of borrowers. Collateral dependent loans are loans in which repayment is expected to be provided solely by the underlying collateral and there are no other available and reliable sources of repayment. Loans are written down to the lower of cost or fair value of underlying collateral, less estimated costs to sell. The Company had $10.0 million and $14.0 million of collateral dependent loans secured by real estate or business assets as of September 30, 2023, and December 31, 2022, respectively. Foreclosures As of September 30, 2023, Busey had $1.0 million of residential real estate in the process of foreclosure. Busey follows Federal Housing Finance Agency guidelines on single-family foreclosures and real estate owned evictions on portfolio loans. Loans Evaluated Individually Busey evaluates loans with disparate risk characteristics on an individual basis. The following tables provide details of loans evaluated individually, segregated by loan category and class. The unpaid principal balance represents customer outstanding contractual principal balances excluding any partial charge-offs. Recorded investment represents the amortized cost of customer balances net of any partial charge-offs recognized on the loan. Average recorded investment is calculated using the most recent four quarters (dollars in thousands) : As of September 30, 2023 Unpaid Recorded Investment Average With No With Total Related Loans evaluated individually Commercial loans: Commercial $ 10,007 $ 597 $ 4,909 $ 5,506 $ 1,576 $ 6,058 Commercial real estate 3,946 1,289 116 1,405 116 4,866 Real estate construction — — — — — 100 Commercial loans evaluated individually 13,953 1,886 5,025 6,911 1,692 11,024 Retail loans: Retail real estate 213 61 25 86 25 1,196 Retail loans evaluated individually 213 61 25 86 25 1,196 Total loans evaluated individually $ 14,166 $ 1,947 $ 5,050 $ 6,997 $ 1,717 $ 12,220 As of December 31, 2022 Unpaid Recorded Investment Average With No With Total Related Loans evaluated individually Commercial loans: Commercial $ 9,589 $ 656 $ 5,918 $ 6,574 $ 2,476 $ 6,761 Commercial real estate 8,039 2,334 3,903 6,237 2,000 5,219 Real estate construction 247 247 — 247 — 260 Commercial loans evaluated individually 17,875 3,237 9,821 13,058 4,476 12,240 Retail loans: Retail real estate 2,733 2,564 25 2,589 25 2,311 Retail loans evaluated individually 2,733 2,564 25 2,589 25 2,311 Total loans evaluated individually $ 20,608 $ 5,801 $ 9,846 $ 15,647 $ 4,501 $ 14,551 Allowance for Credit Losses Management estimates 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 loss experience provides the basis for the estimation of expected credit losses. The cumulative loss rate used as the basis for the estimate of credit losses is comprised of Busey’s historical loss experience beginning in 2010. Due to the continued economic uncertainty in the markets in which the Company operates, Busey will continue to utilize a forecast period of 12 months with an immediate reversion to historical loss rates beyond this forecast period in its ACL estimate. PPP loans were excluded from the ACL calculation as they are 100% government guaranteed. The following tables summarize activity in the ACL attributable to each loan category. Allocation of a portion of the ACL to one category does not preclude its availability to absorb losses in other categories (dollars in thousands) : Three Months Ended September 30, 2023 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, June 30, 2023 $ 24,510 $ 33,656 $ 5,071 $ 24,675 $ 3,727 $ 91,639 Provision for credit losses (1,306) 745 104 674 147 364 Charged-off (758) (102) — (144) (111) (1,115) Recoveries 187 392 31 128 84 822 ACL balance, September 30, 2023 $ 22,633 $ 34,691 $ 5,206 $ 25,333 $ 3,847 $ 91,710 Nine Months Ended September 30, 2023 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, December 31, 2022 $ 23,860 $ 38,299 $ 6,457 $ 18,193 $ 4,799 $ 91,608 Provision for credit losses 79 (3,006) (1,404) 6,975 (700) 1,944 Charged-off (1,733) (1,175) — (252) (483) (3,643) Recoveries 427 573 153 417 231 1,801 ACL balance, September 30, 2023 $ 22,633 $ 34,691 $ 5,206 $ 25,333 $ 3,847 $ 91,710 Three Months Ended September 30, 2022 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, June 30, 2022 $ 23,359 $ 37,182 $ 5,669 $ 17,984 $ 4,563 $ 88,757 Provision for credit losses 615 598 216 684 251 2,364 Charged-off (381) — — (220) (218) (819) Recoveries 102 19 86 172 41 420 ACL balance, September 30, 2022 $ 23,695 $ 37,799 $ 5,971 $ 18,620 $ 4,637 $ 90,722 Nine Months Ended September 30, 2022 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, December 31, 2021 $ 23,855 $ 38,249 $ 5,102 $ 17,589 $ 3,092 $ 87,887 Provision for credit losses 123 408 663 826 1,744 3,764 Charged-off (589) (1,372) — (253) (409) (2,623) Recoveries 306 514 206 458 210 1,694 ACL balance, September 30, 2022 $ 23,695 $ 37,799 $ 5,971 $ 18,620 $ 4,637 $ 90,722 The following tables present the ACL and amortized cost of portfolio loans by loan category and class (dollars in thousands) : As of September 30, 2023 Portfolio Loans ACL Attributed to Portfolio Loans Collectively Individually Total Collectively Individually Total Portfolio loans and related ACL Commercial loans: Commercial $ 1,937,943 $ 5,506 $ 1,943,449 $ 21,057 $ 1,576 $ 22,633 Commercial real estate 3,352,348 1,405 3,353,753 34,575 116 34,691 Real estate construction 527,598 — 527,598 5,206 — 5,206 Commercial loans and related ACL 5,817,889 6,911 5,824,800 60,838 1,692 62,530 Retail loans: Retail real estate 1,715,359 86 1,715,445 25,308 25 25,333 Retail other 315,915 — 315,915 3,847 — 3,847 Retail loans and related ACL 2,031,274 86 2,031,360 29,155 25 29,180 Portfolio loans and related ACL $ 7,849,163 $ 6,997 $ 7,856,160 $ 89,993 $ 1,717 $ 91,710 As of December 31, 2022 Portfolio Loans ACL Attributed to Portfolio Loans Collectively Individually Total Collectively Individually Total Portfolio loans and related ACL Commercial loans: Commercial $ 1,967,580 $ 6,574 $ 1,974,154 $ 21,384 $ 2,476 $ 23,860 Commercial real estate 3,255,636 6,237 3,261,873 36,299 2,000 38,299 Real estate construction 530,222 247 530,469 6,457 — 6,457 Commercial loans and related ACL 5,753,438 13,058 5,766,496 64,140 4,476 68,616 Retail loans: Retail real estate 1,654,493 2,589 1,657,082 18,168 25 18,193 Retail other 302,124 — 302,124 4,799 — 4,799 Retail loans and related ACL 1,956,617 2,589 1,959,206 22,967 25 22,992 Portfolio loans and related ACL $ 7,710,055 $ 15,647 $ 7,725,702 $ 87,107 $ 4,501 $ 91,608

Leases

Leases	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Leases	Leases Busey as the Lessee Busey has operating leases consisting primarily of equipment leases and real estate leases for banking centers, ATM locations, and office space. The following table summarizes lease-related information and balances reported in our Consolidated Balance Sheets (Unaudited) for the periods presented (dollars in thousands) : As of September 30, December 31, Lease balances Right of use assets $ 11,500 $ 12,829 Lease liabilities 11,783 12,995 Supplemental information Year through which lease terms extend 2037 2037 Weighted average remaining lease term, in years 8.49 8.90 Weighted average discount rate 3.56 % 3.45 % The following table represents lease costs and cash flows related to leases for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Lease costs Operating lease costs $ 615 $ 563 $ 1,836 $ 1,762 Variable lease costs 9 214 27 436 Short-term lease costs 15 5 37 15 Total lease cost 1 $ 639 $ 782 $ 1,900 $ 2,213 Cash flows related to leases Cash paid for amounts included in the measurement of lease liabilities: Operating lease cash flows – Fixed payments $ 586 $ 1,076 $ 1,720 $ 2,445 Operating lease cash flows – Liability reduction 483 464 1,423 1,741 Right of use assets obtained during the period in exchange for operating lease liabilities 199 1,127 208 1,182 ___________________________________________ 1. Lease costs are included in net occupancy and equipment expense in the Consolidated Statements of Income (Unaudited). Busey was obligated under noncancelable operating leases for office space and other commitments, as follows (dollars in thousands) : As of Rent commitments Remainder of 2023 $ 566 2024 2,044 2025 1,764 2026 1,442 2027 1,276 2028 1,255 Thereafter 5,478 Total undiscounted cash flows 13,825 Less: Amounts representing interest 2,042 Present value of net future minimum lease payments $ 11,783 Busey as the Lessor Busey occasionally leases parking lots and office space to outside parties. Revenues recorded in connection with these leases, reported in Other income on our Consolidated Statements of Income (Unaudited), are summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Rental income $ 152 $ 146 $ 526 $ 519

Deposits

Deposits	9 Months Ended
	Sep. 30, 2023
Deposits [Abstract]
Deposits	Deposits The composition of Busey’s deposits is as follows (dollars in thousands) : As of September 30, December 31, Deposits Noninterest-bearing demand deposits $ 2,918,574 $ 3,393,666 Interest-bearing transaction deposits 2,856,192 2,857,818 Saving deposits and money market deposits 2,890,944 2,964,421 Time deposits 1,666,652 855,375 Total deposits $ 10,332,362 $ 10,071,280 Additional information about Busey’s deposits follows (dollars in thousands) : As of September 30, December 31, Brokered savings deposits and money market deposits $ 6,055 $ 1,303 Brokered time deposits 283 275 Aggregate amount of time deposits with a minimum denomination of $100,000 976,513 416,445 Aggregate amount of time deposits with a minimum denomination that meets or exceeds the FDIC insurance limit of $250,000 350,276 120,377 Scheduled maturities of time deposits are as follows (dollars in thousands) : As of Time deposits by schedule of maturities Remainder of 2023 $ 251,302 2024 1,322,335 2025 52,337 2026 19,438 2027 12,888 2028 7,813 Thereafter 539 Time deposits $ 1,666,652

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Borrowings	Borrowings Securities Sold Under Agreements to Repurchase Securities sold under agreements to repurchase, which are classified as secured borrowings, generally mature daily. Securities sold under agreements to repurchase are reflected at the amount of cash received in connection with the transaction. The underlying securities are held by Busey’s safekeeping agent. Busey may be required to provide additional collateral based on fluctuations in the fair value of the underlying securities. Securities sold under agreements to repurchase were as follows (dollars in thousands) : As of September 30, December 31, Securities sold under agreements to repurchase $ 183,702 $ 229,806 Weighted average rate for securities sold under agreements to repurchase 3.07 % 1.91 % Term Loan On May 28, 2021, Busey entered into a Second Amended and Restated Credit Agreement, pursuant to which Busey has access to (i) a $40.0 million revolving line of credit with a termination date of April 30, 2022, and (ii) a $60.0 million term loan with a maturity date of May 31, 2026. The loans had an annual interest rate of 1.75% plus the one-month LIBOR rate. On April 30, 2022, the agreement was amended, effecting an extension of the termination date for the revolving line of credit to April 30, 2023, and providing for the transition from a LIBOR-indexed interest rate to a SOFR-indexed interest rate. Under the terms of the amendment, the loans now have an annual interest rate of 1.80% plus the one-month forward-looking term rate based on SOFR. On April 30, 2023, the agreement was further amended to extend the term for the revolving line of credit to April 30, 2024. Proceeds of the term loan were used to fund a part of the cash portion of the merger consideration related to the acquisition of CAC in the second quarter of 2021, and for general corporate purposes. The total outstanding balance on the term loan was $33.0 million as of September 30, 2023, of which $12.0 million was short-term and $21.0 million was long-term. Quarterly payments on the term loan reduce the outstanding principal balance by $3.0 million each quarter. As of September 30, 2023, there was no balance outstanding on the revolving credit facility. The revolving credit facility incurs a non-usage fee based on any undrawn amounts. Short-term Borrowings Busey’s short-term borrowings include loans maturing within one year of the loan origination date, as well as the current portion of long-term debt that is due within 12 months. Short-term borrowings are summarized as follows (dollars in thousands) : As of September 30, December 31, Short-term borrowings FHLB advances maturing in less than one year from date of origination, and the current portion of long-term FHLB advances due within 12 months $ — $ 339,054 Term Loan, current portion due within 12 months 12,000 12,000 Total short-term debt $ 12,000 $ 351,054 Funds borrowed from the FHLB, listed above, consisted of four notes with a weighted average interest rate of 4.28% and a weighted average maturity period of five days as of December 31, 2022. Federal funds purchased are short-term borrowings that generally mature between one day and 90 days. During the first quarter of 2023, Busey purchased federal funds to test operational availability to access funds if needed. Busey had no federal funds purchased as of September 30, 2023, or December 31, 2022. Long-term Debt Busey’s long-term debt consists of loans maturing more than one year from the loan origination date, excluding the current portion that is due within 12 months. Long-term debt is summarized as follows (dollars in thousands) : As of September 30, December 31, Long-term debt Term Loan $ 21,000 $ 30,000 Total long-term debt $ 21,000 $ 30,000 Subordinated Notes On June 1, 2020, Busey issued $125.0 million of fixed-to-floating rate subordinated notes that mature on June 1, 2030. The subordinated notes, which qualify as Tier 2 capital for Busey, bear interest at an annual rate of 5.25% for the first five years after issuance and thereafter bear interest at a floating rate equal to a three-month benchmark rate plus a spread of 5.11%, as calculated on each applicable determination date. Interest on the subordinated notes is payable semi-annually on each June 1 and December 1 during the five-year fixed-term, and thereafter on March 1, June 1, September 1, and December 1 of each year, commencing on September 1, 2025. The subordinated notes have an optional redemption, in whole or in part, on any interest payment date on or after June 1, 2025. The subordinated notes are unsecured obligations of the Company. On June 2, 2022, Busey issued $100.0 million aggregate principal amount of 5.000% fixed-to-floating rate subordinated notes maturing June 15, 2032, which qualify as Tier 2 capital for regulatory purposes. The price to the public for the subordinated notes was 100% of the principal amount of the subordinated notes. Interest on the subordinated notes accrues at a rate equal to (i) 5.000% per annum from the original issue date to, but excluding, June 15, 2027, payable semiannually in arrears, and (ii) a floating rate per annum equal to a benchmark rate, which is expected to be the Three-Month Term SOFR (as defined in the subordinated notes), plus a spread of 252 basis points from and including June 15, 2027, payable quarterly in arrears. The subordinated notes have an optional redemption, in whole or in part, on any interest payment date on or after June 15, 2027. Unamortized debt issuance costs related to senior notes and subordinated notes are presented in the following table (dollars in thousands) : As of September 30, December 31, Unamortized debt issuance costs Subordinated notes issued in 2020 $ 859 $ 1,220 Subordinated notes issued in 2022 1,475 1,742 Total unamortized debt issuance costs $ 2,334 $ 2,962

Regulatory Capital

Regulatory Capital	9 Months Ended
	Sep. 30, 2023
Banking and Thrift, Other Disclosure [Abstract]
Regulatory Capital	Regulatory Capital First Busey Corporation and Busey Bank are subject to various regulatory capital requirements administered by federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory—and possibly additional discretionary—actions by regulators that, if undertaken, could have a direct material effect on Busey's consolidated financial statements. Capital amounts and classification also are subject to qualitative judgments by regulators about components, risk weightings, and other factors. Banking regulations identify five capital categories for insured depository institutions: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized, and critically undercapitalized. As of September 30, 2023, and December 31, 2022, all capital ratios of First Busey Corporation and Busey Bank exceeded well capitalized levels under the applicable regulatory capital adequacy guidelines. Management believes that no events or changes have occurred subsequent to September 30, 2023, that would change this designation. Current Expected Credit Loss Model On August 26, 2020, the FDIC and other federal banking agencies adopted a final rule which provided banking organizations that adopted CECL during 2020 with the option to delay for two years the estimated impact of CECL on regulatory capital and to phase in the aggregate impact of the deferral on regulatory capital over a subsequent three-year period. Under this final rule, because the Company has elected to use the deferral option, the regulatory capital impact of our transition adjustments recorded on January 1, 2020, arising from the adoption of CECL, was deferred for two years. In addition, 25 percent of the ongoing impact of CECL on our ACL, retained earnings, and average total consolidated assets from January 1, 2020, through the end of the two-year deferral period, each as reported for regulatory capital purposes, has been added to the deferred transition amounts (“adjusted transition amounts”) and deferred for the two-year period. On January 1, 2022, at the conclusion of the two-year period, the adjusted transition amounts began to be phased-in for regulatory capital purposes at a rate of 25 percent per year, with the phased-in amounts included in regulatory capital at the beginning of each year. Capital Amounts and Ratios The following tables summarize regulatory capital requirements applicable to First Busey Corporation and Busey Bank (dollars in thousands) : As of September 30, 2023 Actual Minimum Minimum Amount Ratio Amount Ratio Amount Ratio Common equity Tier 1 capital to risk weighted assets First Busey $ 1,144,403 12.52 % $ 411,165 4.50 % $ 593,905 6.50 % Busey Bank $ 1,356,565 14.89 % $ 409,979 4.50 % $ 592,192 6.50 % Tier 1 capital to risk weighted assets First Busey $ 1,218,403 13.33 % $ 548,220 6.00 % $ 730,960 8.00 % Busey Bank $ 1,356,565 14.89 % $ 546,639 6.00 % $ 728,852 8.00 % Total capital to risk weighted assets First Busey $ 1,527,627 16.72 % $ 730,960 8.00 % $ 913,700 10.00 % Busey Bank $ 1,440,789 15.81 % $ 728,852 8.00 % $ 911,064 10.00 % Leverage ratio of Tier 1 capital to average assets First Busey $ 1,218,403 10.08 % $ 483,272 4.00 % N/A N/A Busey Bank $ 1,356,565 11.26 % $ 481,856 4.00 % $ 602,321 5.00 % As of December 31, 2022 Actual Minimum Minimum Amount Ratio Amount Ratio Amount Ratio Common equity Tier 1 capital to risk weighted assets First Busey $ 1,081,686 11.96 % $ 406,980 4.50 % $ 587,861 6.50 % Busey Bank $ 1,306,716 14.49 % $ 405,736 4.50 % $ 586,063 6.50 % Tier 1 capital to risk weighted assets First Busey $ 1,155,686 12.78 % $ 542,640 6.00 % $ 723,521 8.00 % Busey Bank $ 1,306,716 14.49 % $ 540,981 6.00 % $ 721,308 8.00 % Total capital to risk weighted assets First Busey $ 1,457,994 16.12 % $ 723,521 8.00 % $ 904,401 10.00 % Busey Bank $ 1,384,024 15.35 % $ 721,308 8.00 % $ 901,635 10.00 % Leverage ratio of Tier 1 capital to average assets First Busey $ 1,155,686 9.45 % $ 489,124 4.00 % N/A N/A Busey Bank $ 1,306,716 10.72 % $ 487,541 4.00 % $ 609,426 5.00 % Capital Conservation Buffer In July 2013, U.S. federal banking authorities approved the Basel III Rule for strengthening international capital standards. The Basel III Rule introduced a capital conservation buffer, composed entirely of common equity Tier 1 capital, which is added to the minimum risk-weighted asset ratios. The capital conservation buffer is not a minimum capital requirement; however, banking institutions with a ratio of common equity Tier 1 capital to risk-weighted assets below the capital conservation buffer will face constraints on dividends, equity repurchases, and discretionary bonus payments based on the amount of the shortfall. In order to refrain from restrictions on dividends, equity repurchases, and discretionary bonus payments, banking institutions must maintain minimum ratios of (i) common equity Tier 1 capital to risk-weighted assets of at least 7.0%, (ii) Tier 1 capital to risk-weighted assets of at least 8.5%, and (iii) total capital to risk-weighted assets of at least 10.5%.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Stock Options Busey has outstanding stock options assumed from acquisitions. A summary of the status of, and changes in, the Company's stock option awards for the nine months ended September 30, 2023, follows: Shares Weighted- Weighted- Options outstanding at December 31, 2022 26,106 $ 23.53 3.88 Forfeited (4,180) 23.53 Options outstanding at September 30, 2023 21,926 23.53 3.13 Options exercisable at September 30, 2023 21,926 23.53 3.13 Amended 2020 Equity Plan The 2020 Equity Plan was approved by stockholders at the 2020 Annual Meeting of Stockholders. A description of the 2020 Equity Plan can be found in Appendix A within Busey’s Proxy Statement for the 2020 Annual Meeting of Stockholders filed on April 9, 2020 . The Amended 2020 Equity Plan was approved by stockholders at the 2023 Annual Meeting of Stockholders. The terms of the Amended 2020 Equity Plan are substantially identical to those of the stockholder approved 2020 Equity Plan, other than a 1,350,000 increase in the number of shares authorized for issuance under the plan. More information can be found in Appendix A within Busey’s Proxy Statement for the 2023 Annual Meeting of Stockholders filed on April 14, 2023 . Under the terms of the 2020 Equity Plan, Busey has granted RSU, PSU, and DSU awards. Upon vesting and delivery, shares are expected, though not required, to be issued from treasury. There were 1,525,987 shares available for issuance under the Amended 2020 Equity Plan as of September 30, 2023. RSU Awards Busey grants RSUs to members of management periodically throughout the year. Each RSU is equivalent to one share of Busey’s common stock. These units have requisite service periods ranging from one year to five years, subject to accelerated vesting upon eligible retirement from the Company. Recipients earn quarterly dividend equivalents on their respective units which entitle the recipients to additional units. Therefore, dividends earned each quarter compound based upon the updated unit balances. On March 22, 2023, under the terms of the 2020 Equity Plan, Busey granted 224,316 RSUs to members of management. The grant date fair value of the award totaled $4.6 million and will be recognized as compensation expense over the requisite service period ranging from one year to five years. The terms of these awards included an accelerated vesting provision upon eligible retirement from the Company, after a one-year minimum requisite service period. Subsequent to the requisite service period, the awards will become 100% vested. A summary of changes in Busey’s RSU awards for the nine months ended September 30, 2023, is as follows: RSU Awards Shares Weighted- Nonvested at December 31, 2022 1,096,931 $ 23.61 Granted 224,316 20.44 Dividend equivalents earned 43,841 20.53 Vested (150,806) 29.91 Forfeited (14,145) 22.00 Nonvested at September 30, 2023 1,200,137 22.13 PSU Awards Busey grants PSUs, which are restricted stock units that are subject to certain performance criteria, to members of management periodically throughout the year. Each PSU is equivalent to one share of Busey’s common stock. The number of units that ultimately vest will be determined based on the achievement of the market or other performance goals, subject to accelerated service-based vesting conditions upon eligible retirement from the Company. On March 22, 2023, under the terms of the 2020 Equity Plan, Busey granted a target of 104,643 PSUs with a maximum award of 167,429 units. The actual number of units issued at the vesting date could range from 0% to 160% of the initial grant, depending on attaining a market-based total stockholder return performance goal. The grant date fair value of the award was $2.0 million and will be recognized in compensation expense over the performance period ending December 31, 2025. On March 22, 2023, under the terms of the 2020 Equity Plan, Busey granted a target of 104,643 PSUs with a maximum award of 167,429 units. The actual number of units issued at the vesting date could range from 0% to 160% of the initial grant, depending on attaining an adjusted return on average tangible common equity performance goal. The grant date fair value of the award was $2.1 million and will be recognized in compensation expense over the performance period ending December 31, 2025. The actual amount of compensation expense recognized may vary, subject to achievement of the performance goal. On March 22, 2023, under the terms of the 2020 Equity Plan, Busey granted a target of 15,045 PSUs with a maximum award of 30,090 units. The actual number of units issued at the vesting date could range from 0% to 200% of the initial grant, depending on attaining a performance goal based upon the compounded annual revenue growth rate of the FirsTech operating segment. The grant date fair value of the award was $0.3 million and will be recognized in compensation expense over the performance period ending December 31, 2025, subject to achievement of the performance goal. A summary of changes in Busey’s PSU awards for the nine months ended September 30, 2023, is as follows: PSU Awards Shares 1 Weighted- Nonvested at December 31, 2022 285,351 $ 25.40 Granted 224,331 20.04 Dividend equivalents earned 92 22.85 Vested (13,155) 25.50 Forfeited (40,159) 24.98 Nonvested at September 30, 2023 456,460 22.80 Vested and outstanding at September 30, 2023² 13,063 25.52 ___________________________________________ 1. Shares for PSU awards represent target shares at the grant date. 2. Reported at target, as performance determination and settlement activity will take place in the fourth quarter of 2023. DSU Awards Busey grants DSUs, which are restricted stock units with a deferred settlement date, to its directors and advisory directors. Each DSU is equivalent to one share of Busey’s common stock. DSUs vest over a one-year period following the grant date. Under both the 2020 Equity Plan and the Amended 2020 Equity Plan, DSUs are generally are subject to the same terms as RSUs, except that following vesting of DSUs, settlement occurs within 30 days following the earlier of separation from the board or a change in control of the Company. After vesting and prior to delivery, these units will continue to earn dividend equivalents. On March 22, 2023, under the terms of the 2020 Equity Plan, Busey granted 41,548 DSUs to directors and advisory directors. The grant date fair value of the award totaled $0.8 million and will be recognized as compensation expense over the requisite service period of one year. Subsequent to the requisite service period, the awards will become 100% vested. A summary of changes in Busey’s DSU awards for the nine months ended September 30, 2023, is as follows: DSU Awards Shares Weighted- Nonvested at December 31, 2022 31,085 $ 25.75 Granted 41,548 20.44 Dividend equivalents earned 6,010 20.48 Vested (36,078) 25.04 Forfeited (73) 20.44 Nonvested at September 30, 2023 42,492 20.42 Vested and outstanding at September 30, 2023 142,347 23.58 2021 Employee Stock Purchase Plan The First Busey Corporation 2021 ESPP was approved at Busey’s 2021 Annual Meeting of Stockholders and details can be found in Appendix A within First Busey’s Definitive Proxy Statement filed with the SEC on April 8, 2021 . The purpose of the 2021 ESPP is to provide a means through which our employees may acquire a proprietary interest in the Company by purchasing shares of our common stock at a 15% discount through voluntary payroll deductions, to assist us in retaining the services of our employees and securing and retaining the services of new employees, and to provide incentives for our employees to exert maximum efforts toward our success. The 2021 ESPP initially reserved for issuance and purchase an aggregate of 600,000 shares of Busey’s common stock. The first offering under the 2021 ESPP began on July 1, 2021. There were 460,340 shares available for issuance under the 2021 ESPP as of September 30, 2023. Stock-based Compensation Expense Busey did not record any stock option compensation expense for the three or nine months ended September 30, 2023, or 2022. As of September 30, 2023, the Company did not have any unrecognized stock option compensation expense. Busey recognized compensation expense related to nonvested RSU, PSU, and DSU awards, as well as the 2021 ESPP, as summarized in the table below (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Stock-based compensation expense RSU awards $ 1,177 $ 1,072 $ 3,428 $ 3,521 PSU awards 1 1,180 1,172 2,724 2,342 DSU awards 213 196 620 679 2021 ESPP 33 36 156 179 Total stock-based compensation expense $ 2,603 $ 2,476 $ 6,928 $ 6,721 ___________________________________________ 1. Expense for PSU awards with a market-based total stockholder return performance goal represents amounts based on target shares at the grant date. Expense for PSU awards with return on average tangible common equity and compounded annual revenue growth rate performance goals represents amounts based on target shares at the grant date, adjusted for performance expectations as of the date indicated. Unamortized compensation expense related to nonvested RSU, PSU, and DSU awards is summarized in the table below (dollars in thousands) : As of September 30, December 31, Unamortized stock-based compensation RSU awards $ 9,437 $ 8,570 PSU awards 1 5,942 4,279 DSU awards 403 175 Total unamortized stock-based compensation $ 15,782 $ 13,024 Weighted average period over which expense is to be recognized 2.5 years 2.5 years ___________________________________________ 1. Unamortized expense for PSU awards with a market-based total stockholder return performance goal represents amounts based on target shares at grant date. Unamortized expense for PSU awards with return on average tangible common equity and compounded annual revenue growth rate performance goals represents amounts based on target shares at grant date, adjusted for performance expectations as of the date indicated.

Outstanding Commitments and Con

Outstanding Commitments and Contingent Liabilities	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Outstanding Commitments and Contingent Liabilities	Outstanding Commitments and Contingent Liabilities Legal Matters Busey is a party to legal actions which arise in the normal course of its business activities. Legal and administrative proceedings are subject to inherent uncertainties, and while unfavorable outcomes could occur, Busey does not believe at this time that any potential liabilities relating to pending or potential legal matters are likely to have a material impact on Busey's results of operations or financial position. Credit Commitments and Contingencies A summary of the contractual amount of Busey’s exposure to off-balance-sheet risk relating to the Company’s commitments to extend credit and standby letters of credit follows (dollars in thousands) : As of September 30, December 31, Financial instruments whose contract amounts represent credit risk Commitments to extend credit $ 2,130,938 $ 1,991,769 Standby letters of credit 36,847 33,008 Total commitments $ 2,167,785 $ 2,024,777

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments Busey utilizes interest rate swap agreements as part of its asset liability management strategy to help manage its interest rate risk position. Additionally, Busey enters into derivative financial instruments, including interest rate lock commitments issued to residential loan customers for loans that will be held for sale; forward sales commitments to sell residential mortgage loans to investors; and interest rate swaps, risk participation agreements, and foreign currency exchange contracts with customers and other third parties. See “ Note 11: Fair Value Measurements ” for further discussion of the fair value measurement of such derivatives. To secure its obligations under derivative contracts, Busey pledged cash and held collateral as follows (dollars in thousands) : As of September 30, December 31, Cash pledged to secure obligations under derivative contracts $ 34,210 $ 38,609 Collateral held to secure obligations under derivative contracts 34,620 29,830 Derivative Instruments Designated as Hedges Busey entered into derivative instruments designated as cash flow hedges. For a derivative instrument that is designated and qualifies as a cash flow hedge, the change in fair value of the derivative instrument is reported as a component of OCI and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. Changes in fair value of components excluded from the assessment of effectiveness are recognized in current earnings. Interest Rate Swaps Designated as Cash Flow Hedges Interest rate swaps with notional amounts totaling $350.0 million as of both September 30, 2023, and December 31, 2022, were designated as cash flow hedges. Busey entered into one $50.0 million interest rate swap to hedge the risks of variability in cash flows for future interest payments attributable to changes in the contractually specified 3-month LIBOR benchmark interest rate on the Busey’s junior subordinated debt owed to unconsolidated trusts (Debt Swap). In addition, Busey entered into one $300.0 million receive fixed pay floating interest rate swap to reduce Busey’s asset sensitivity (Loan Swap). Duration was added to our loan portfolio by fixing a portion of floating prime based loans. Interest rates had risen above their historical lows allowing Busey to lock in a portion of its loan portfolio to reduce asset sensitivity while creating a more stable margin in a volatile rate market. These hedges were determined to be highly effective during the period, and Busey expects its hedges to remain highly effective during the remaining terms of the swaps. Changes in fair value were recorded net of tax in OCI. A summary of the interest-rate swaps designated as cash flow hedges is presented below (dollars in thousands) : As of Location September 30, December 31, Debt Swap Notional amount $ 50,000 $ 50,000 Weighted average fixed pay rates 1.79 % 1.79 % Weighted average variable 3-month LIBOR receive rates 5.55 % 4.77 % Weighted average maturity 0.96 years 1.71 years Loan Swap Notional amount $ 300,000 $ 300,000 Weighted average fixed receive rates 4.81 % 4.81 % Weighted average variable Prime pay rates 8.50 % 7.32 % Weighted average maturity 5.35 years 6.10 years Gross aggregate fair value of the swaps Gross aggregate fair value of swap assets Other assets $ 1,886 $ 2,535 Gross aggregate fair value of swap liabilities Other liabilities 37,725 32,367 Balances carried in AOCI Unrealized gains (losses) on cash flow hedges, net of tax AOCI $ (25,092) $ (20,985) Busey expects to reclassify unrealized gains and losses from OCI to interest income and interest expense as shown in the following table, during the next 12 months (dollars in thousands) . Amounts actually recognized could differ from these expectations due to changes in interest rates, hedge de-designations, and the addition of other hedges subsequent to September 30, 2023. As of Unrealized gains (losses) in OCI expected to be recognized in income Unrealized losses expected to be reclassified from OCI to interest income $ (922) Unrealized gains expected to be reclassified from OCI to interest expense 481 Net unrealized gains (losses) in OCI expected to be recognized in net interest income $ (441) Interest expense recorded on these swap transactions was as follows for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Interest on swap transactions Increase (decrease) in interest income on swap transactions $ (2,771) $ (405) $ (7,500) $ 947 (Increase) decrease in interest expense on swap transactions 481 35 1,268 (250) Net increase (decrease) in net interest income on swap transactions $ (2,290) $ (370) $ (6,232) $ 697 The following table reflects the net gains (losses) relating to cash flow derivative instruments that were recorded in AOCI and the Consolidated Statements of Income (Unaudited) during the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Unrealized gains (losses) on cash flow hedges Net gain (loss) recognized in OCI, net of tax $ (5,577) $ (10,192) $ (8,563) $ (21,587) (Gain) loss reclassified from OCI to interest income, net of tax 1,982 (24) 5,362 (992) (Gain) loss reclassified from OCI to interest expense, net of tax (344) 290 (906) 494 Net change in unrealized gains (losses) on cash flow hedges, net of tax $ (3,939) $ (9,926) $ (4,107) $ (22,085) Derivative Instruments Not Designated as Hedges Interest Rate Swaps Not Designated as Hedges Busey may offer derivative contracts to its customers in connection with their risk management needs. Busey manages the risk associated with these contracts by entering into equal and offsetting derivative agreements with third-party dealers. These contracts support variable rate, commercial loan relationships totaling $628.3 million as of September 30, 2023, and $576.9 million as of December 31, 2022. These derivatives generally work together as an economic interest rate hedge, but Busey did not designate them for hedge accounting treatment. Consequently, changes in fair value of the corresponding derivative financial asset or liability are recorded as either a charge or credit to current earnings during the period in which the changes occurred. Amounts and fair values of derivative assets and liabilities related to customer interest rate swaps recorded in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 Derivative Asset Derivative Liability Notional Fair Notional Fair Derivatives not designated as hedging instruments Interest rate swaps – pay floating, receive fixed $ 9,320 $ 99 $ 618,971 $ 44,914 Interest rate swaps – pay fixed, receive floating 618,971 44,914 9,320 99 Total derivatives not designated as hedging instruments $ 628,291 $ 45,013 $ 628,291 $ 45,013 As of December 31, 2022 Derivative Asset Derivative Liability Notional Fair Notional Fair Derivatives not designated as hedging instruments Interest rate swaps – pay floating, receive fixed $ 48,728 $ 370 $ 528,183 $ 39,685 Interest rate swaps – pay fixed, receive floating 528,183 39,685 48,728 370 Total derivatives not designated as hedging instruments $ 576,911 $ 40,055 $ 576,911 $ 40,055 Changes in fair value of these derivative assets and liabilities are recorded in noninterest expense in the Consolidated Statements of Income (Unaudited) and summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, Location 2023 2022 2023 2022 Interest rate swaps Pay floating, receive fixed Noninterest expense $ 9,007 $ 18,317 $ 4,646 $ 21,792 Pay fixed, receive floating Noninterest expense (9,007) (18,317) (4,646) (21,792) Net change in fair value of interest rate swaps $ — $ — $ — $ — Risk Participation Agreements To manage the credit risk exposure related to customer-facing swaps, Busey entered into risk participation agreements in conjunction with loan participation arrangements with other financial institutions. Under these risk participation agreements, Busey purchased a portion of the credit exposure, paying an up-front fee, and will receive a payment from the counterparty if the loan customer defaults on its obligations. Busey also entered into a risk participation agreement under which Busey sold a portion of its credit exposure, receiving an up-front fee, and will be required to make a payment to the counterparty if the loan customer defaults on its obligations. The notional amount of the risk participation agreements reflect Busey's pro-rata share of the derivative instrument, consistent with its share of the related participated loan. The risk participation agreements mature between 2024 and 2029, and are summarized as follows (dollars in thousands) : As of September 30, December 31, Risk participation agreements purchased Number of risk participation agreements 3 2 Notional amount $ 34,274 $ 18,899 Fair value 7 5 Risk participation agreements sold Number of risk participation agreements 1 — Notional amount $ 20,001 — Fair value — — Foreign Currency Forward Contracts Busey entered into foreign currency exchange contracts to support the business requirements of its customers. Foreign currency contracts involve the exchange of one currency for another on a specified date and at a specified rate. These contracts are executed on behalf of Busey's customers and are used by customers to manage fluctuations in foreign exchange rates. Busey minimizes its exposure by entering into similar offsetting positions with other financial institutions. Busey is subject to the credit risk that another party will fail to perform. Amounts and fair values of derivative assets and liabilities related to foreign currency contracts recorded in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 Derivative Asset Derivative Liability Notional Fair Notional Fair Foreign currency forward contracts Foreign currency exchange forward contract (Buy) $ 354 $ 58 $ — $ — Foreign currency exchange forward contract (Sell) — — 344 (48) Total foreign currency forward contracts $ 354 $ 58 $ 344 $ (48) Mortgage Banking Derivatives Interest Rate Lock Commitments Interest rate lock commitments that meet the definition of derivative financial instruments under ASC Topic 815 “Derivatives and Hedging” are carried at their fair values in other assets or other liabilities in the Consolidated Balance Sheets (Unaudited), with changes in the fair values of the corresponding derivative financial assets or liabilities recorded as either a charge or credit to current earnings during the period in which the changes occurred. Forward Sales Commitments Busey economically hedges mortgage loans held for sale and interest rate lock commitments issued to its residential loan customers related to loans that will be held for sale by obtaining corresponding forward sales commitments with an investor to sell the loans at an agreed-upon price at the time the interest rate locks are issued to the customers. Forward sales commitments that meet the definition of derivative financial instruments under ASC Topic 815 “Derivatives and Hedging” are carried at their fair values in other assets or other liabilities in the Consolidated Balance Sheets (Unaudited). While such forward sales commitments generally served as an economic hedge to mortgage loans held for sale and interest rate lock commitments, Busey did not designate them for hedge accounting treatment. Changes in fair value of the corresponding derivative financial asset or liability were recorded as either a charge or credit to current earnings during the period in which the changes occurred. Amounts and fair values of mortgage banking derivatives included in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 As of December 31, 2022 Location Notional Fair Notional Fair Derivatives with positive fair value Interest rate lock commitments Other assets $ 715 $ 4 $ 1,517 $ 16 Forward sales commitments Other assets 3,249 66 83 1 Mortgage banking derivatives recorded in other assets $ 3,964 $ 70 $ 1,600 $ 17 Derivatives with negative fair value Interest rate lock commitments Other liabilities $ 1,366 $ 16 $ 83 $ 1 Forward sales commitments Other liabilities 1,795 12 2,757 39 Mortgage banking derivatives recorded in other liabilities $ 3,161 $ 28 $ 2,840 $ 40 Net gains (losses) relating to these derivative instruments are summarized as follows for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, Location 2023 2022 2023 2022 Net gains (losses) Interest rate lock commitments Mortgage revenue $ (16) $ (111) $ (28) $ 38 Forward sales commitments Mortgage revenue 60 295 92 82 Net gains (losses) $ 44 $ 184 $ 64 $ 120

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The fair value of an asset or liability is the price that would be received by selling that asset or paid in transferring that liability (exit price) in an orderly transaction occurring in the principal market (or most advantageous market in the absence of a principal market) for such asset or liability. ASC Topic 820 “Fair Value Measurement” establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows: • Level 1 Inputs —Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. • Level 2 Inputs —Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These might include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit risks, etc.) or inputs that are derived principally from or corroborated by market data by correlation or other means. • Level 3 Inputs —Unobservable inputs for determining the fair values of assets or liabilities that reflect the Company’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. These valuation methodologies were applied to those Company assets and liabilities that are carried at fair value. In general, fair value is based upon quoted market prices, when available. If such quoted market prices are not available, fair values are measured utilizing independent valuation techniques of identical or similar securities for which significant assumptions are derived primarily from or corroborated by observable data. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. These adjustments may include amounts to reflect, among other things, counterparty credit quality and the company's creditworthiness as well as unobservable parameters. Any such valuation adjustments are applied consistently over time. While management believes Busey's valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis Debt Securities Available for Sale Debt securities classified as available for sale are reported at fair value utilizing Level 2 inputs. Busey obtains fair value measurements from an independent pricing service. The independent pricing service utilizes evaluated pricing models that vary by asset class and incorporate available trade, bid, and other market information. Because many fixed income securities do not trade on a daily basis, the independent pricing service applies available information, focusing on observable market data such as benchmark curves, benchmarking of like securities, sector groupings, and matrix pricing, to prepare evaluations. The independent pricing service uses model processes, such as the Option Adjusted Spread model, to assess interest rate impact and develop prepayment scenarios. Models and processes take into account market conventions. For each asset class, a team of evaluators gathers information from market sources and integrates relevant credit information, perceived market movements, and sector news into the evaluated pricing applications and models. Market inputs that the independent pricing service normally seeks for evaluations of securities, listed in approximate order of priority, include: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. The independent pricing service also monitors market indicators, industry, and economic events. For certain security types, additional inputs may be used or some of the market inputs may not be applicable. Evaluators may prioritize inputs differently on any given day for any security based on market conditions, and not all inputs listed are available for use in the evaluation process for each security evaluation on a given day. Because the data utilized was observable, the securities have been classified as Level 2. Equity Securities Equity securities are reported at fair value utilizing Level 1 or Level 2 inputs. Fair value measurements of mutual funds, when held, are determined using unadjusted quoted prices in active markets for identical assets at the measurement date and are classified as Level 1. Fair value measurements of stock utilize quoted prices for identical or similar assets in markets that are not active and are classified as Level 2. Derivative Assets and Derivative Liabilities The majority of our derivative assets and derivative liabilities are reported at fair value utilizing Level 2 or Level 3 inputs. Fair values of derivative assets and liabilities are determined based on prices that are obtained from a third-party which uses observable market inputs and, with the exception of our risk participation agreements, are classified as Level 2. Due to the significance of unobservable inputs, derivative assets related to our risk participation agreements are classified as Level 3. The following tables summarize financial assets and financial liabilities measured at fair value on a recurring basis as of September 30, 2023, and December 31, 2022, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands) : As of September 30, 2023 Level 1 Level 2 Level 3 Total Debt securities available for sale: U.S. Treasury securities $ — $ 50,130 $ — $ 50,130 Obligations of U.S. government corporations and agencies — 9,819 — 9,819 Obligations of states and political subdivisions — 226,797 — 226,797 Asset-backed securities — 479,448 — 479,448 Commercial mortgage-backed securities — 100,300 — 100,300 Residential mortgage-backed securities — 1,088,796 — 1,088,796 Corporate debt securities — 227,551 — 227,551 Equity securities — 8,782 — 8,782 Derivative assets — 47,027 7 47,034 Derivative liabilities — 82,814 — 82,814 As of December 31, 2022 Level 1 Level 2 Level 3 Total Debt securities available for sale: U.S. Treasury securities $ — $ 114,061 $ — $ 114,061 Obligations of U.S. government corporations and agencies — 19,779 — 19,779 Obligations of states and political subdivisions — 257,512 — 257,512 Asset-backed securities — 469,875 — 469,875 Commercial mortgage-backed securities — 108,394 — 108,394 Residential mortgage-backed securities — 1,243,256 — 1,243,256 Corporate debt securities — 248,516 — 248,516 Equity securities — 11,535 — 11,535 Derivative assets — 42,607 5 42,612 Derivative liabilities — 72,462 — 72,462 Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Certain financial assets and financial liabilities are measured at fair value on a non-recurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). Loans Evaluated Individually Busey does not record portfolio loans at fair value on a recurring basis. However, periodically, a loan is evaluated individually and is reported at the fair value of the underlying collateral, less estimated costs to sell, if repayment is expected solely from the collateral. If the collateral value is not sufficient, a specific reserve is recorded. Collateral values are estimated using a combination of observable inputs, including recent appraisals, and unobservable inputs based on customized discounting criteria. Due to the significance of unobservable inputs, fair values of individually evaluated collateral dependent loans have been classified as Level 3. OREO and Other Repossessed Assets Non-financial assets measured at fair value, upon initial recognition or subsequent impairment, include OREO and other repossessed assets. OREO properties and other repossessed assets are measured using a combination of observable inputs, including recent appraisals, and unobservable inputs. Due to the significance of unobservable inputs, the fair values of all OREO and other repossessed assets have been classified as Level 3. Bank Property Held for Sale Bank property held for sale represents certain banking center office buildings which Busey has closed and consolidated with other existing banking centers. Bank property held for sale is measured at the lower of amortized cost or fair value less estimated costs to sell. Fair values were based upon discounted appraisals or real estate listing prices. Due to the significance of unobservable inputs, fair values of all bank property held for sale have been classified as Level 3. The following tables summarize assets and liabilities measured at fair value on a non-recurring basis for the periods presented, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands) : As of September 30, 2023 Level 1 Level 2 Level 3 Total Loans evaluated individually, net of related allowance $ — $ — $ 3,333 $ 3,333 Bank property held for sale with impairment — — 4,286 4,286 As of December 31, 2022 Level 1 Level 2 Level 3 Total Loans evaluated individually, net of related allowance $ — $ — $ 5,345 $ 5,345 Bank property held for sale with impairment — — 7,923 7,923 The following table presents additional quantitative information about assets measured at fair value on a non-recurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands) : As of September 30, 2023 Fair Value Valuation Unobservable Range Loans evaluated individually, net of related allowance $ 3,333 Appraisal of collateral Appraisal adjustments -10.5% to -100.0% (-34.0)% Bank property held for sale with impairment 4,286 Appraisal of collateral or real estate listing price Appraisal adjustments -6.2% to -64.9% (-38.4)% As of December 31, 2022 Fair Value Valuation Techniques Unobservable Input Range (Weighted Average) Loans evaluated individually, net of related allowance $ 5,345 Appraisal of collateral Appraisal adjustments -22.7% to -100.0% (-45.7)% Bank property held for sale with impairment 7,923 Appraisal of collateral or real estate listing price Appraisal adjustments -0.7% to -70.1% (-35.1)% Financial Assets and Financial Liabilities That Are Not Carried at Fair Value Estimated fair values of financial instruments that are not carried at fair value in Busey’s Consolidated Balance Sheets (Unaudited), segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows (dollars in thousands) : As of September 30, 2023 As of December 31, 2022 Carrying Fair Carrying Fair Financial assets Level 1 inputs: Cash and cash equivalents $ 337,919 $ 337,919 $ 227,164 $ 227,164 Level 2 inputs: Debt securities held to maturity 882,614 701,676 918,312 785,295 Loans held for sale 3,051 3,059 1,253 1,276 Accrued interest receivable 47,889 47,889 43,372 43,372 Level 3 inputs: Portfolio loans, net 7,764,450 7,241,479 7,634,094 7,320,422 Mortgage servicing rights 3,870 18,758 5,861 18,284 Other servicing rights 1,675 2,144 1,914 2,331 Financial liabilities Level 2 inputs: Time deposits $ 1,666,652 $ 1,643,625 $ 855,375 $ 830,596 Securities sold under agreements to repurchase 183,702 183,702 229,806 229,806 Short-term borrowings 12,000 12,027 351,054 351,085 Long-term debt 21,000 21,020 30,000 30,052 Junior subordinated debt owed to unconsolidated trusts 71,946 55,662 71,810 59,111 Accrued interest payable 22,761 22,761 3,978 3,978 Level 3 inputs: Subordinated notes, net of unamortized issuance costs 222,666 198,812 222,038 208,562

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share Basic earnings per share is computed by dividing net income for the period by the weighted average number of common shares outstanding, which include DSUs that are vested but not delivered. Diluted earnings per common share is computed using the treasury stock method and reflects the potential dilution that could occur if Busey’s outstanding stock options and warrants were exercised, stock units were vested, and ESPP shares were issued. Earnings per common share have been computed as follows (dollars in thousands, except per share amounts) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net income $ 30,666 $ 35,661 $ 96,816 $ 93,924 Weighted average number of common shares outstanding, basic 55,486,700 55,349,547 55,441,980 55,399,424 Dilutive effect of common stock equivalents: Options — 249 — 1,606 Warrants — 1,708 432 1,749 RSU awards 640,714 624,576 638,495 661,173 PSU awards 165,868 81,268 126,787 37,393 DSU awards 16,792 10,414 14,996 14,275 ESPP 5,418 5,402 7,934 8,136 Weighted average number of common shares outstanding, diluted 56,315,492 56,073,164 56,230,624 56,123,756 Basic earnings per common share $ 0.55 $ 0.64 $ 1.75 $ 1.70 Diluted earnings per common share $ 0.54 $ 0.64 $ 1.72 $ 1.67 Average shares that were excluded from the computation of diluted earnings per common share because their effect would have been anti-dilutive are summarized in the table below for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Anti-dilutive common stock equivalents Options 21,926 — 22,219 10,389 RSU awards — — 52,594 51,883 PSU awards 85,074 160,391 137,918 226,771 Total anti-dilutive common stock equivalents 107,000 160,391 212,731 289,043

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2023
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Alternative [Abstract]
Accumulated Other Comprehensive Income (Loss).	Accumulated Other Comprehensive Income (Loss) The following tables present changes in AOCI by component, net of tax, for the periods indicated (dollars in thousands) : Three Months Ended September 30, 2023 2022 Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized/Unrecognized gains (losses) on debt securities Balance at beginning of period $ (335,359) $ 95,591 $ (239,768) $ (277,310) $ 79,047 $ (198,263) Unrealized holding gains (losses) on debt securities available for sale, net (37,696) 10,746 (26,950) (96,937) 27,631 (69,306) Amounts reclassified from AOCI, net 33 (9) 24 74 (21) 53 Amortization of unrecognized losses on securities transferred to held to maturity 1,476 (420) 1,056 1,806 (515) 1,291 Balance at end of period $ (371,546) $ 105,908 $ (265,638) $ (372,367) $ 106,142 $ (266,225) Unrealized gains (losses) on cash flow hedges Balance at beginning of period $ (29,586) $ 8,433 $ (21,153) $ (17,963) $ 5,119 $ (12,844) Unrealized holding gains (losses) on cash flow hedges, net (7,797) 2,220 (5,577) (14,253) 4,061 (10,192) Amounts reclassified from AOCI, net 2,290 (652) 1,638 370 (104) 266 Balance at end of period $ (35,093) $ 10,001 $ (25,092) $ (31,846) $ 9,076 $ (22,770) Total AOCI $ (406,639) $ 115,909 $ (290,730) $ (404,213) $ 115,218 $ (288,995) Nine Months Ended September 30, 2023 2022 Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized/Unrecognized gains (losses) on debt securities Balance at beginning of period $ (352,878) $ 100,585 $ (252,293) $ (32,272) $ 9,199 $ (23,073) Unrealized holding gains (losses) on debt securities available for sale, net (23,600) 6,728 (16,872) (296,507) 84,519 (211,988) Unrecognized losses on debt securities transferred to held to maturity from available for sale — — — (48,456) 13,812 (34,644) Amounts reclassified from AOCI, net 207 (59) 148 (28) 8 (20) Amortization of unrecognized losses on securities transferred to held to maturity 4,725 (1,346) 3,379 4,896 (1,396) 3,500 Balance at end of period $ (371,546) $ 105,908 $ (265,638) $ (372,367) $ 106,142 $ (266,225) Unrealized gains (losses) on cash flow hedges Balance at beginning of period $ (29,350) $ 8,365 $ (20,985) $ (958) $ 273 $ (685) Unrealized holding gains (losses) on cash flow hedges, net (11,975) 3,412 (8,563) (30,191) 8,604 (21,587) Amounts reclassified from AOCI, net 6,232 (1,776) 4,456 (697) 199 (498) Balance at end of period $ (35,093) $ 10,001 $ (25,092) $ (31,846) $ 9,076 $ (22,770) Total AOCI $ (406,639) $ 115,909 $ (290,730) $ (404,213) $ 115,218 $ (288,995)

Operating Segments and Related

Operating Segments and Related Information	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Operating Segments and Related Information	Operating Segments and Related Information Busey has three reportable operating segments: Banking, FirsTech, and Wealth Management. Busey’s three operating segments are strategic business units that are separately managed, as they offer different products and services and have different marketing strategies. The Banking Operating Segment The Banking operating segment provides a full range of banking services to individual and corporate customers through First Busey Corporation’s wholly-owned bank subsidiary, Busey Bank, with 58 banking centers in Illinois; the St. Louis, Missouri, metropolitan area; southwest Florida; and Indianapolis, Indiana. Banking services offered to individual customers include customary types of demand and savings deposits, money transfers, safe deposit services, individual retirement accounts and other fiduciary services, automated teller machines, and technology-based networks, as well as a variety of loan products including residential real estate, home equity lines of credit, and consumer loans. Banking services offered to corporate customers include commercial, commercial real estate, real estate construction, and agricultural loans, as well as commercial depository services such as cash management. The Wealth Management Operating Segment The Wealth Management operating segment provides a full range of asset management, investment, brokerage, fiduciary, philanthropic advisory, tax preparation, and farm management services to individuals, businesses, and foundations. Services are provided through Busey Capital Management, Inc., a wholly-owned subsidiary of Busey Bank, and Busey Wealth Management, a division of Busey Bank. Wealth management services tailored to individuals include trust and estate advisory services and financial planning. Business services include business succession planning and employee retirement plan services. Services for foundations include investment strategy consulting and fiduciary services. The FirsTech Operating Segment The FirsTech operating segment provides comprehensive and innovative payment technology solutions through Busey Bank’s wholly-owned subsidiary, FirsTech. FirsTech's multi-channel payment platform allows businesses to collect payments from their customers in a variety of ways to enable fast, frictionless payments. Payment method vehicles include, but are not limited to, text-based mobile bill pay; interactive voice response; electronic payment concentration delivered to Automated Clearing House networks, money management, and credit card networks; walk-in payment processing for customers at retail pay agents; customer service payments made over a telephone; direct debit services; and lockbox remittance processing for customers to make payments by mail. FirsTech also provides additional tools to help clients with billing, reconciliation, bill reminders, and treasury services. FirsTech's client base represents a diverse set of industries, with a higher concentration in highly regulated industries, such as financial institutions, utility, insurance, and telecommunications industries. Segment Financial Information The segment financial information provided below has been derived from information used by management to monitor and manage Busey’s financial performance. The accounting policies of the three operating segments are the same as those described in the summary of significant accounting policies in “ Note 1. Significant Accounting Policies ” in Busey’s 2022 Annual Report . The Company accounts for intersegment revenue and transfers at current market value. Following is a summary of selected financial information for the Company’s operating segments. The “other” category included in the tables below consists of the parent company, First Busey Risk Management, and the elimination of intercompany transactions (dollars in thousands) : Goodwill Total Assets As of As of September 30, December 31, September 30, December 31, Operating segment Banking $ 294,773 $ 294,773 $ 12,104,706 $ 12,199,960 Wealth Management 14,108 14,108 98,755 84,082 FirsTech 8,992 8,992 50,689 48,715 Other — — 4,100 3,920 Consolidated total $ 317,873 $ 317,873 $ 12,258,250 $ 12,336,677 Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net interest income Banking $ 81,794 $ 90,916 $ 254,394 $ 244,820 FirsTech 14 15 41 50 Other (4,017) (4,626) (12,117) (12,581) Total net interest income $ 77,791 $ 86,305 $ 242,318 $ 232,289 Noninterest income Banking $ 11,983 $ 13,559 $ 34,716 $ 42,827 Wealth Management 14,350 12,514 43,993 42,425 FirsTech 5,665 5,578 16,954 16,333 Other (990) (718) (4,795) (3,861) Total noninterest income $ 31,008 $ 30,933 $ 90,868 $ 97,724 Noninterest expense Banking $ 55,172 $ 55,273 $ 163,314 $ 165,220 Wealth Management 8,059 7,682 24,821 23,533 FirsTech 5,245 5,109 16,303 14,601 Other 2,469 2,672 6,115 6,850 Total noninterest expense $ 70,945 $ 70,736 $ 210,553 $ 210,204 Income before income taxes Banking $ 38,241 $ 46,838 $ 123,852 $ 118,663 Wealth Management 6,291 4,832 19,172 18,892 FirsTech 434 484 692 1,782 Other (7,476) (8,016) (23,027) (23,292) Total income before income taxes $ 37,490 $ 44,138 $ 120,689 $ 116,045 Net income Banking $ 31,189 $ 37,082 $ 98,689 $ 94,032 Wealth Management 4,781 3,756 14,571 14,688 FirsTech 317 353 505 1,300 Other (5,621) (5,530) (16,949) (16,096) Total net income $ 30,666 $ 35,661 $ 96,816 $ 93,924

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net income	$ 30,666	$ 35,661	$ 96,816	$ 93,924

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations First Busey Corporation, a Nevada corporation organized in 1980, is a $12.3 billion financial holding company headquartered in Champaign, Illinois. Busey’s common stock is traded on The Nasdaq Global Select Market under the symbol “BUSE.” First Busey operates and reports its business in three segments: Banking, Wealth Management, and FirsTech. • The Banking operating segment provides a full range of banking services to individual and corporate customers through its banking center network in Illinois; the St. Louis, Missouri metropolitan area; southwest Florida; and Indianapolis, Indiana. • The Wealth Management operating segment provides a full range of asset management, investment, brokerage, fiduciary, philanthropic advisory, tax preparation, and farm management services to individuals, businesses, and foundations. • The FirsTech operating segment provides comprehensive and innovative payment technology solutions including online, mobile, and voice-recognition bill payments; money management and credit card networks; direct debit services; lockbox remittance processing for payments made by mail; and walk-in payments. FirsTech also provides additional tools to help clients with billing, reconciliation, bill reminders, and treasury services. For additional information about First Busey's operating segments, see “ Note 14. Operating Segments and Related Information .”
Basis of Financial Statement Presentation	Basis of Financial Statement Presentation These unaudited consolidated financial statements and related notes should be read in conjunction with the audited consolidated financial statements included in Busey's 2022 Annual Report . These interim unaudited consolidated financial statements serve to update our 2022 Annual Report and may not include all information and notes necessary to constitute a complete set of financial statements. We prepared these unaudited consolidated financial statements in conformity with GAAP. We have eliminated intercompany accounts and transactions. We have also reclassified certain prior year amounts to conform to the current period presentation. These reclassifications did not have a material impact on our consolidated financial condition or results of operations. In our opinion, the unaudited consolidated financial statements reflect all normal, recurring adjustments needed to present fairly our results for the interim periods. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the full year or any other interim period.
Use of Estimates	Use of Estimates In preparing the accompanying unaudited consolidated financial statements in conformity with GAAP, Busey’s management is required to make estimates and assumptions that affect the amounts reported in the financial statements and the disclosures provided. Actual results could differ from those estimates. Material estimates which are particularly susceptible to significant change in the near term relate to the fair value of debt securities available for sale, fair value of assets acquired and liabilities assumed in business combinations, goodwill, income taxes, and the determination of the ACL.
Impact of Recently Adopted Accounting Standards	Impact of Recently Adopted Accounting Standards In July 2023, the FASB issued ASU 2023-03 “Presentation of Financial Statements (Topic 205), Income Statement—Reporting Comprehensive Income (Topic 220), Distinguishing Liabilities from Equity (Topic 480), Equity (Topic 505), and Compensation—Stock Compensation (Topic 718)” pursuant to: (i) SEC Staff Accounting Bulletin No. 120, which provided interpretive guidance related to estimating the fair value of share-based payment transactions while in possession of material non-public information; (ii) an SEC Staff Announcement at the March 24, 2022, Emerging Issues Task Force Meeting, which provided interpretive guidance on accounting for share-based payments to employees and non-employees; and (iii) Staff Accounting Bulletin Topic 6.B, Accounting Series Release 280—General Revision of Regulation S-X: Income or Loss Applicable to Common Stock, which provided interpretive guidance on the reporting of income or loss applicable to common stock. This update was reflected in the Accounting Standards Codification upon issuance. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. In March 2022, the FASB issued ASU 2022-02 “Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures,” which eliminates the TDR accounting model for creditors that have already adopted CECL. In lieu of the TDR accounting model, loan refinancing and restructuring guidance in ASC Subtopic 310-20-35-9 through 35-11 “Receivables—Nonrefundable Fees and Other Costs—Subsequent Measurement—Loan Refinancing or Restructuring” will apply to all loan modifications, including those made for borrowers experiencing financial difficulty. This standard also enhances disclosure requirements related to certain loan modifications. Additionally, this standard introduces new requirements to disclose gross write-off information in the vintage disclosures of financing receivables by credit quality indicator and class of financing receivable by year of origination. This standard applies prospectively. For the transition method related to the recognition and measurement of TDRs, there is an option to apply a modified retrospective transition method, resulting in a cumulative-effect adjustment to retained earnings in the period of adoption. This standard became effective for Busey beginning January 1, 2023. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. In March 2022, the FASB issued ASU 2022-01 “Derivatives and Hedging (Topic 815): Fair Value Hedging—Portfolio Layer Method,” which replaces the current last-of-layer hedge accounting method with an expanded portfolio layer method that permits multiple hedged layers of a single closed portfolio. The scope of the portfolio layer method is also expanded to include non-prepayable financial assets. This update also provides additional guidance on the accounting for and disclosure of hedge basis adjustments that are applicable to the portfolio layer method, and specifies how hedge basis adjustments should be considered when determining credit losses for the assets included in the closed portfolio. Amendments related to hedge basis adjustments which are included in this standard apply on a modified retrospective basis by means of a cumulative-effect adjustment to the opening balance of retained earnings on the initial application date. Amendments related to disclosure which are included in this standard may be applied on a prospective basis from the initial application date, or on a retrospective basis to each prior period presented after the date of adoption of the amendments in ASU 2017-12 “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.” This standard became effective for Busey beginning January 1, 2023. Adoption of this standard did not have a material impact on Busey’s financial position or results of operations. ASU 2021-08 “Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers” requires measurement and recognition in accordance with ASC Topic 606 “Revenue from Contracts with Customers” for contract assets and contract liabilities acquired in a business combination. This update became effective for Busey beginning January 1, 2023. This standard applied prospectively to all business combinations that occurred on or after the date of adoption. Adoption of this standard did not have an impact on Busey’s financial position or results of operations. Recently Issued Accounting Standards Not Yet Adopted In March 2023, the FASB issued ASU 2023-02 “Investments—Equity Method and Joint Ventures (Topic 323),” permitting an election to use the proportional amortization method to account for equity investments made primarily for the purpose of receiving income tax credits and other income tax benefits, regardless of the tax credit program from which the income tax credits are received, provided that certain conditions are met. The proportional amortization method results in the cost of the investment being amortized in proportion to the income tax credits and other income tax benefits received, with the amortization of the investment and the income tax credits being presented net in the income statement as a component of income tax expense. This standard must be applied on a retrospective or modified retrospective basis, and is applicable for Busey beginning on January 1, 2024. Early adoption is permitted. Busey is currently evaluating the potential effect on the Company’s financial position and results of operations, and upon adoption expects changes to be reflected in the Other Expense and Income Taxes line items in the Consolidated Statements of Income (Unaudited). In March 2023, the FASB issued ASU 2023-01 “Leases (Topic 842): Common Control Arrangements,” which requires amortization over the useful life of leasehold improvements (not the lease term) when the lease is between entities under common control, and any value of such leasehold improvements remaining at the end of the lease term is to be accounted for as a transfer between entities under common control. This standard may be adopted either prospectively, or retrospectively, and is effective for Busey beginning January 1, 2024. Early adoption is permitted. Busey does not expect adoption of this standard to have a material impact on the Company’s financial position and results of operations. In June 2022, the FASB issued ASU 2022-03 “Fair Value Measurements (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions,” which clarifies that contractual restrictions on the sale of equity securities are not considered in measuring the fair value of those equity securities, and further that contractual sale restrictions cannot be recognized and measured as a separate unit of account. This standard applies prospectively, and is effective for Busey beginning January 1, 2024. Early adoption is permitted. Busey is currently evaluating the potential effect on the Company’s financial position and results of operations.
Subsequent Events	Subsequent Events Busey has evaluated subsequent events for potential recognition and/or disclosure through the date the unaudited consolidated financial statements included in this Quarterly Report were issued. The Company issued a Form 8‑K on October 24, 2023 , regarding the departure of a named executive officer, and during the fourth quarter of 2023 expects to record related severance expenses according to Schedule 1 of the Separation Letter that was filed as Exhibit 10.1 to the Form 8‑K . Other than this, there were no significant subsequent events for the quarter ended September 30, 2023, through the filing date of these unaudited consolidated financial statements.

Debt Securities (Tables)

Debt Securities (Tables)	9 Months Ended
	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Schedule of amortized cost, unrealized gains and losses and fair values of securities classified available for sale and held to maturity	The tables below provide the amortized cost, unrealized gains and losses, and fair values of debt securities summarized by major category (dollars in thousands) : As of September 30, 2023 Amortized Unrealized Fair Gross Gains Gross Losses Debt securities available for sale U.S. Treasury securities $ 51,522 $ — $ (1,392) $ 50,130 Obligations of U.S. government corporations and agencies 10,071 2 (254) 9,819 Obligations of states and political subdivisions 1 254,549 6 (27,758) 226,797 Asset-backed securities 486,517 — (7,069) 479,448 Commercial mortgage-backed securities 120,117 — (19,817) 100,300 Residential mortgage-backed securities 2 1,343,324 — (254,528) 1,088,796 Corporate debt securities 251,194 91 (23,734) 227,551 Total debt securities available for sale $ 2,517,294 $ 99 $ (334,552) $ 2,182,841 ___________________________________________ 1. Includes securities marked at par, with no gain or loss to report. 2. Gross gains on Residential mortgage-backed securities were insignificant, rounding to zero thousand. Amortized Unrecognized Fair Gross Gains Gross Losses Debt securities held to maturity Commercial mortgage-backed securities $ 459,866 $ — $ (93,401) $ 366,465 Residential mortgage-backed securities 422,748 — (87,537) 335,211 Total debt securities held to maturity $ 882,614 $ — $ (180,938) $ 701,676 As of December 31, 2022 Amortized Unrealized Fair Gross Gains Gross Losses Debt securities available for sale U.S. Treasury securities $ 117,805 $ — $ (3,744) $ 114,061 Obligations of U.S. government corporations and agencies 20,097 3 (321) 19,779 Obligations of states and political subdivisions 283,481 106 (26,075) 257,512 Asset-backed securities 489,558 — (19,683) 469,875 Commercial mortgage-backed securities 124,423 — (16,029) 108,394 Residential mortgage-backed securities 1,463,971 2 (220,717) 1,243,256 Corporate debt securities 273,118 33 (24,635) 248,516 Total debt securities available for sale $ 2,772,453 $ 144 $ (311,204) $ 2,461,393 Amortized Unrecognized Fair Gross Gains Gross Losses Debt securities held to maturity Commercial mortgage-backed securities $ 474,820 $ — $ (63,738) $ 411,082 Residential mortgage-backed securities 443,492 — (69,279) 374,213 Total debt securities held to maturity $ 918,312 $ — $ (133,017) $ 785,295
Maturities of debt securities	All mortgage-backed securities were issued by U.S. government corporations and agencies (dollars in thousands) : As of September 30, 2023 Amortized Fair Debt securities available for sale Due in one year or less $ 109,189 $ 106,940 Due after one year through five years 312,419 289,027 Due after five years through ten years 431,297 389,702 Due after ten years 1,664,389 1,397,172 Debt securities available for sale $ 2,517,294 $ 2,182,841 Debt securities held to maturity Due after one year through five years $ 63,474 $ 58,144 Due after five years through ten years 40,076 34,985 Due after ten years 779,064 608,547 Debt securities held to maturity $ 882,614 $ 701,676
Gains and losses on debt securities	Realized gains and losses related to sales and calls of debt securities available for sale are summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Realized gains and losses on debt securities Gross gains on debt securities $ 10 $ — $ 20 $ 114 Gross (losses) on debt securities (43) (74) (227) (86) Realized net gains (losses) on debt securities 1 $ (33) $ (74) $ (207) $ 28 ___________________________________________ 1. Net gains (losses) on sales of securities reported in the Consolidated Statements of Income (Unaudited) include sales of equity securities, excluded in this table.
Debt securities in an unrealized loss position	The following information pertains to debt securities with gross unrealized or unrecognized losses, aggregated by investment category and the length of time that individual securities have been in a continuous loss position (dollars in thousands) : As of September 30, 2023 Less than 12 months 12 months or more Total Fair Unrealized Fair Unrealized Fair Unrealized Debt securities available for sale U.S. Treasury securities $ — $ — $ 50,130 $ (1,392) $ 50,130 $ (1,392) Obligations of U.S. government corporations and agencies 1,983 (6) 7,699 (248) 9,682 (254) Obligations of states and political subdivisions 45,778 (1,219) 177,195 (26,539) 222,973 (27,758) Asset-backed securities — — 479,448 (7,069) 479,448 (7,069) Commercial mortgage-backed securities — — 100,300 (19,817) 100,300 (19,817) Residential mortgage-backed securities 431 (10) 1,088,344 (254,518) 1,088,775 (254,528) Corporate debt securities 1,457 (2) 219,074 (23,732) 220,531 (23,734) Debt securities available for sale with gross unrealized losses $ 49,649 $ (1,237) $ 2,122,190 $ (333,315) $ 2,171,839 $ (334,552) 12 months or more Total Fair Unrecognized Fair Unrecognized Debt securities held to maturity Commercial mortgage-backed securities $ 366,465 $ (93,401) $ 366,465 $ (93,401) Residential mortgage-backed securities 335,211 (87,537) 335,211 (87,537) Debt securities held to maturity with gross unrecognized losses $ 701,676 $ (180,938) $ 701,676 $ (180,938) As of December 31, 2022 Less than 12 months 12 months or more Total Fair Unrealized Fair Unrealized Fair Unrealized Debt securities available for sale U.S. Treasury securities 1 $ 74 $ — $ 113,987 $ (3,744) $ 114,061 $ (3,744) Obligations of U.S. government corporations and agencies 19,603 (321) — — 19,603 (321) Obligations of states and political subdivisions 166,147 (10,059) 75,217 (16,016) 241,364 (26,075) Asset-backed securities 390,164 (15,648) 79,711 (4,035) 469,875 (19,683) Commercial mortgage-backed securities 89,428 (12,623) 18,966 (3,406) 108,394 (16,029) Residential mortgage-backed securities 366,221 (38,111) 876,668 (182,606) 1,242,889 (220,717) Corporate debt securities 39,037 (5,079) 204,310 (19,556) 243,347 (24,635) Debt securities available for sale with gross unrealized losses $ 1,070,674 $ (81,841) $ 1,368,859 $ (229,363) $ 2,439,533 $ (311,204) Less than 12 months 12 months or more Total Fair Unrecognized Fair Unrecognized Fair Unrecognized Debt securities held to maturity Commercial mortgage-backed securities $ 58,065 $ (8,009) $ 353,017 $ (55,729) $ 411,082 $ (63,738) Residential mortgage-backed securities — — 374,213 (69,279) 374,213 (69,279) Debt securities held to maturity with gross unrecognized losses $ 58,065 $ (8,009) $ 727,230 $ (125,008) $ 785,295 $ (133,017) ___________________________________________ 1. Unrealized losses for U.S. Treasury securities that had been in a continuous unrealized loss position for less than 12 months were insignificant, rounding to zero thousand. Additional information about debt securities in an unrealized or unrecognized loss position is presented in the tables below (dollars in thousands) : As of September 30, 2023 Available for Sale Held to Maturity Total Debt securities with gross unrealized or unrecognized losses, fair value $ 2,171,839 $ 701,676 $ 2,873,515 Gross unrealized or unrecognized losses on debt securities 334,552 180,938 515,490 Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses 15.4 % 25.8 % 17.9 % Count of debt securities 1,001 55 1,056 Count of debt securities in an unrealized or unrecognized loss position 982 55 1,037 As of December 31, 2022 Available for Sale Held to Maturity Total Debt securities with gross unrealized or unrecognized losses, fair value $ 2,439,533 $ 785,295 $ 3,224,828 Gross unrealized or unrecognized losses on debt securities 311,204 133,017 444,221 Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses 12.8 % 16.9 % 13.8 % Count of debt securities 1,091 55 1,146 Count of debt securities in an unrealized or unrecognized loss position 1,032 55 1,087

Portfolio Loans (Tables)

Portfolio Loans (Tables)	9 Months Ended
	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Distribution of portfolio loans	Distributions of the loan portfolio by loan category and class is presented in the following table (dollars in thousands) : As of September 30, December 31, Commercial loans Commercial $ 1,943,449 $ 1,974,154 Commercial real estate 3,353,753 3,261,873 Real estate construction 527,598 530,469 Total commercial loans 5,824,800 5,766,496 Retail loans Retail real estate 1,715,445 1,657,082 Retail other 315,915 302,124 Total retail loans 2,031,360 1,959,206 Total portfolio loans 7,856,160 7,725,702 ACL (91,710) (91,608) Portfolio loans, net $ 7,764,450 $ 7,634,094
Schedule of financial instruments owned and pledged as collateral	Busey had loans pledged to the FHLB and Federal Reserve for liquidity as set forth in the table below (dollars in thousands) : As of September 30, December 31, Pledged loans FHLB $ 4,852,634 $ 5,095,448 Federal Reserve Bank 858,312 804,718 Total pledged loans $ 5,710,946 $ 5,900,166 To secure its obligations under derivative contracts, Busey pledged cash and held collateral as follows (dollars in thousands) : As of September 30, December 31, Cash pledged to secure obligations under derivative contracts $ 34,210 $ 38,609 Collateral held to secure obligations under derivative contracts 34,620 29,830
Summary of risk grades segregated by category of portfolio loans (excluding accretable purchase accounting adjustments and clearings)	The following table is a summary of risk grades segregated by category and class of portfolio loans (dollars in thousands) : As of September 30, 2023 Pass Watch Special Substandard Substandard Total Commercial loans Commercial $ 1,533,562 $ 350,820 $ 24,705 $ 28,734 $ 5,628 $ 1,943,449 Commercial real estate 2,944,191 351,494 44,771 11,739 1,558 3,353,753 Real estate construction 513,218 9,027 — 5,353 — 527,598 Total commercial loans 4,990,971 711,341 69,476 45,826 7,186 5,824,800 Retail loans Retail real estate 1,698,692 10,245 642 1,824 4,042 1,715,445 Retail other 315,845 — — — 70 315,915 Total retail loans 2,014,537 10,245 642 1,824 4,112 2,031,360 Total portfolio loans $ 7,005,508 $ 721,586 $ 70,118 $ 47,650 $ 11,298 $ 7,856,160 As of December 31, 2022 Pass Watch Special Substandard Substandard Total Commercial loans Commercial $ 1,668,495 $ 201,758 $ 46,540 $ 51,187 $ 6,174 $ 1,974,154 Commercial real estate 2,851,709 326,455 43,526 34,539 5,644 3,261,873 Real estate construction 502,904 25,164 1 2,400 — 530,469 Total commercial loans 5,023,108 553,377 90,067 88,126 11,818 5,766,496 Retail loans Retail real estate 1,639,599 10,520 1,338 2,529 3,096 1,657,082 Retail other 301,971 — — — 153 302,124 Total retail loans 1,941,570 10,520 1,338 2,529 3,249 1,959,206 Total portfolio loans $ 6,964,678 $ 563,897 $ 91,405 $ 90,655 $ 15,067 $ 7,725,702
Risk grades of portfolio loans, further sorted by origination	Risk grades of portfolio loans and net charge-offs are presented in the tables below by loan class, further sorted by origination year (dollars in thousands) : As of and For The Nine Months Ended September 30, 2023 Term Loans Amortized Cost Basis by Origination Year Revolving Total Risk Grade Ratings 2023 2022 2021 2020 2019 Prior Commercial Pass $ 279,467 $ 255,619 $ 181,603 $ 74,600 $ 39,483 $ 152,523 $ 550,267 $ 1,533,562 Watch 112,285 59,685 44,244 25,119 7,526 24,532 77,429 350,820 Special Mention 616 541 651 1,104 499 6,937 14,357 24,705 Substandard 8,901 912 1,119 445 3,948 1,859 11,550 28,734 Substandard non-accrual 583 — 2,605 103 130 507 1,700 5,628 Total commercial 401,852 316,757 230,222 101,371 51,586 186,358 655,303 1,943,449 Current period charge-offs — — 420 — 316 997 — 1,733 Commercial real estate Pass 352,661 850,371 778,662 404,109 281,889 258,207 18,292 2,944,191 Watch 82,748 45,945 69,450 33,694 79,906 34,700 5,051 351,494 Special Mention 18,753 1,597 13,762 3,908 3,330 3,421 — 44,771 Substandard 1,882 193 904 2,987 1,831 3,898 44 11,739 Substandard non-accrual 225 533 165 25 — 610 — 1,558 Total commercial real estate 456,269 898,639 862,943 444,723 366,956 300,836 23,387 3,353,753 Current period charge-offs — — — — 239 936 — 1,175 Real estate construction Pass 152,897 171,900 104,963 54,943 1,365 3,899 23,251 513,218 Watch 1,065 4,453 253 3,214 42 — — 9,027 Substandard 5,353 — — — — — — 5,353 Total real estate construction 159,315 176,353 105,216 58,157 1,407 3,899 23,251 527,598 Retail real estate Pass 201,140 379,512 420,164 162,295 71,102 274,617 189,862 1,698,692 Watch 767 2,704 2,877 973 579 596 1,749 10,245 Special Mention 204 55 — — — 383 — 642 Substandard 73 73 295 53 82 1,010 238 1,824 Substandard non-accrual — 538 56 187 101 2,434 726 4,042 Total retail real estate 202,184 382,882 423,392 163,508 71,864 279,040 192,575 1,715,445 Current period charge-offs — 5 — 29 62 156 — 252 Retail other Pass 86,096 102,834 25,977 8,172 6,388 1,539 84,839 315,845 Substandard non-accrual — 63 — 3 3 1 — 70 Total retail other 86,096 102,897 25,977 8,175 6,391 1,540 84,839 315,915 Current period charge-offs 4 71 157 1 — 250 — 483 Total portfolio loans $ 1,305,716 $ 1,877,528 $ 1,647,750 $ 775,934 $ 498,204 $ 771,673 $ 979,355 $ 7,856,160 Total current period charge-offs $ 4 $ 76 $ 577 $ 30 $ 617 $ 2,339 $ — $ 3,643 As of December 31, 2022 Term Loans Amortized Cost Basis by Origination Year Revolving Total Risk Grade Ratings 2022 2021 2020 2019 2018 Prior Commercial Pass $ 479,893 $ 266,122 $ 136,445 $ 52,046 $ 50,764 $ 135,000 $ 548,225 $ 1,668,495 Watch 54,195 49,382 3,288 7,201 1,258 2,160 84,274 201,758 Special Mention 1,958 937 1,642 974 1,000 17,024 23,005 46,540 Substandard 8,926 1,165 570 6,671 2,382 5,191 26,282 51,187 Substandard non-accrual 21 3,292 226 135 — 100 2,400 6,174 Total commercial 544,993 320,898 142,171 67,027 55,404 159,475 684,186 1,974,154 Commercial real estate Pass 883,688 819,133 478,452 297,525 161,409 198,419 13,083 2,851,709 Watch 77,346 56,113 64,282 96,664 21,592 5,758 4,700 326,455 Special Mention 11,943 5,389 12,386 1,420 6,917 5,471 — 43,526 Substandard 5,340 13,528 3,454 1,907 10,248 62 — 34,539 Substandard non-accrual — 3,959 33 — 1,647 5 — 5,644 Total commercial real estate 978,317 898,122 558,607 397,516 201,813 209,715 17,783 3,261,873 Real estate construction Pass 219,112 191,724 68,015 1,490 1,901 1,751 18,911 502,904 Watch 8,530 12,019 3,169 48 — 1,398 — 25,164 Special Mention — — — 1 — — — 1 Substandard 2,400 — — — — — — 2,400 Total real estate construction 230,042 203,743 71,184 1,539 1,901 3,149 18,911 530,469 Retail real estate Pass 396,547 456,158 175,148 77,569 56,887 267,387 209,903 1,639,599 Watch 2,928 2,991 1,846 1,444 1,063 27 221 10,520 Special Mention 945 — — — — 393 — 1,338 Substandard 77 732 198 81 141 1,293 7 2,529 Substandard non-accrual 10 191 107 32 390 1,708 658 3,096 Total retail real estate 400,507 460,072 177,299 79,126 58,481 270,808 210,789 1,657,082 Retail other Pass 134,567 43,512 13,141 13,086 5,646 991 91,028 301,971 Substandard non-accrual 14 134 3 — — 2 — 153 Total retail other 134,581 43,646 13,144 13,086 5,646 993 91,028 302,124 Total portfolio loans $ 2,288,440 $ 1,926,481 $ 962,405 $ 558,294 $ 323,245 $ 644,140 $ 1,022,697 $ 7,725,702
Summary of portfolio loans that are past due and still accruing or on a non-accrual status	An analysis of the amortized cost basis of portfolio loans that are past due and still accruing, or on a non-accrual status, is as follows (dollars in thousands) : As of September 30, 2023 Loans past due, still accruing Non-accrual 30-59 Days 60-89 Days 90+Days Past due and non-accrual loans Commercial loans: Commercial $ — $ 112 $ 51 $ 5,628 Commercial real estate — 109 — 1,558 Real estate construction — 244 — — Past due and non-accrual commercial loans — 465 51 7,186 Retail loans: Retail real estate 3,643 840 558 4,042 Retail other 914 72 100 70 Past due and non-accrual retail loans 4,557 912 658 4,112 Total past due and non-accrual loans $ 4,557 $ 1,377 $ 709 $ 11,298 As of December 31, 2022 Loans past due, still accruing Non-accrual 30-59 Days 60-89 Days 90+Days Past due and non-accrual loans Commercial loans: Commercial $ 2 $ — $ — $ 6,174 Commercial real estate 124 — — 5,644 Past due and non-accrual commercial loans 126 — — 11,818 Retail loans: Retail real estate 4,709 1,239 673 3,096 Retail other 414 60 — 153 Past due and non-accrual retail loans 5,123 1,299 673 3,249 Total past due and non-accrual loans $ 5,249 $ 1,299 $ 673 $ 15,067
Schedule of loan modifications made to borrowers experiencing financial difficulty	The following tables show the amortized cost basis of loans that were modified for borrowers experiencing financial difficulty during the periods indicated, disaggregated by class of financing receivable and type of concession granted (dollars in thousands) : Three Months Ended September 30, 2023 Interest Rate Reduction 1 % of Total Class of Financing Receivable 2 Term Extension 3 % of Total Class of Financing Receivable 2 Loan class: Commercial $ — — % $ 12,026 0.6 % Commercial real estate 880 — % 553 — % Total of loans modified during the period 4 $ 880 — % $ 12,579 0.2 % ___________________________________________ 1. For one loan, the default rate was removed once forbearance was entered. 2. Modified loans represent an insignificant portion of commercial real estate loans, rounding to zero percent. 3. Modifications to extend loan terms also included, in some cases, interest rate increases during the extension period. 4. All modifications were for loans classified as substandard. Nine Months Ended September 30, 2023 Interest Rate Reduction 1 % of Total Class of Financing Receivable 2 Payment Deferral 3 % of Total Class of Financing Receivable 2 Term Extension 4 % of Total Class of Financing Receivable 2 Loan class: Commercial $ — — % $ — — % $ 17,334 0.9 % Commercial real estate 880 — % 225 — % 1,003 — % Real estate construction — — % — — % 5,353 1.0 % Total of loans modified during the period 5 $ 880 — % $ 225 — % $ 23,690 0.3 % ___________________________________________ 1. For one loan, the default rate was removed once forbearance was entered. 2. Modified loans represent an insignificant portion of commercial real estate loans, rounding to zero percent. 3. A loan with payment deferral was modified to defer all principal payments until the end of the loan term, which was shortened. 4. Modifications to extend loan terms also included, in some cases, interest rate increases during the extension period. 5. Modifications include two loans on non-accrual status, and the remaining loans were classified as substandard. The following table summarizes the effects of loan modifications made during the periods indicated, for borrowers experiencing financial difficulty: Three Months Ended September 30, 2023 Nine Months Ended September 30, 2023 Weighted Average Interest Rate Reduction Weighted Average Term Extension Weighted Average Interest Rate Reduction Weighted Average Term Extension Loan class: Commercial 15.3 months 14.3 months Commercial real estate 2.50 % 9.0 months 2.50 % 11.2 months Real estate construction 12.0 months Total financial effect 2.50 % 15.0 months 2.50 % 13.7 months (dollars in thousands) . A default occurs when a loan is 90 days or more past due or transferred to non-accrual status. Nine Months Ended September 30, 2023 Payment Deferral Term Extension Loan class: Commercial $ — $ 500 Commercial real estate 225 — Amortized cost of modified loans with subsequent defaults $ 225 $ 500 Busey closely monitors the performance of the loans that are modified to borrowers experiencing financial difficulty to understand the effectiveness of its modification efforts. The following table depicts the payment performance of loans modified on or after January 1, 2023, the date we adopted ASU 2022-02 (dollars in thousands) : As of September 30, 2023 Current Non-accrual Loan class: Commercial $ 16,834 $ 500 Commercial real estate 1,883 225 Real estate construction 5,353 — Amortized cost of modified loans $ 24,070 $ 725
Schedule of details of impaired loans, segregated by category	Average recorded investment is calculated using the most recent four quarters (dollars in thousands) : As of September 30, 2023 Unpaid Recorded Investment Average With No With Total Related Loans evaluated individually Commercial loans: Commercial $ 10,007 $ 597 $ 4,909 $ 5,506 $ 1,576 $ 6,058 Commercial real estate 3,946 1,289 116 1,405 116 4,866 Real estate construction — — — — — 100 Commercial loans evaluated individually 13,953 1,886 5,025 6,911 1,692 11,024 Retail loans: Retail real estate 213 61 25 86 25 1,196 Retail loans evaluated individually 213 61 25 86 25 1,196 Total loans evaluated individually $ 14,166 $ 1,947 $ 5,050 $ 6,997 $ 1,717 $ 12,220 As of December 31, 2022 Unpaid Recorded Investment Average With No With Total Related Loans evaluated individually Commercial loans: Commercial $ 9,589 $ 656 $ 5,918 $ 6,574 $ 2,476 $ 6,761 Commercial real estate 8,039 2,334 3,903 6,237 2,000 5,219 Real estate construction 247 247 — 247 — 260 Commercial loans evaluated individually 17,875 3,237 9,821 13,058 4,476 12,240 Retail loans: Retail real estate 2,733 2,564 25 2,589 25 2,311 Retail loans evaluated individually 2,733 2,564 25 2,589 25 2,311 Total loans evaluated individually $ 20,608 $ 5,801 $ 9,846 $ 15,647 $ 4,501 $ 14,551
Schedule of activity on the allowance for loan losses	The following tables summarize activity in the ACL attributable to each loan category. Allocation of a portion of the ACL to one category does not preclude its availability to absorb losses in other categories (dollars in thousands) : Three Months Ended September 30, 2023 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, June 30, 2023 $ 24,510 $ 33,656 $ 5,071 $ 24,675 $ 3,727 $ 91,639 Provision for credit losses (1,306) 745 104 674 147 364 Charged-off (758) (102) — (144) (111) (1,115) Recoveries 187 392 31 128 84 822 ACL balance, September 30, 2023 $ 22,633 $ 34,691 $ 5,206 $ 25,333 $ 3,847 $ 91,710 Nine Months Ended September 30, 2023 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, December 31, 2022 $ 23,860 $ 38,299 $ 6,457 $ 18,193 $ 4,799 $ 91,608 Provision for credit losses 79 (3,006) (1,404) 6,975 (700) 1,944 Charged-off (1,733) (1,175) — (252) (483) (3,643) Recoveries 427 573 153 417 231 1,801 ACL balance, September 30, 2023 $ 22,633 $ 34,691 $ 5,206 $ 25,333 $ 3,847 $ 91,710 Three Months Ended September 30, 2022 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, June 30, 2022 $ 23,359 $ 37,182 $ 5,669 $ 17,984 $ 4,563 $ 88,757 Provision for credit losses 615 598 216 684 251 2,364 Charged-off (381) — — (220) (218) (819) Recoveries 102 19 86 172 41 420 ACL balance, September 30, 2022 $ 23,695 $ 37,799 $ 5,971 $ 18,620 $ 4,637 $ 90,722 Nine Months Ended September 30, 2022 Commercial Commercial Real Estate Retail Retail Other Total ACL balance, December 31, 2021 $ 23,855 $ 38,249 $ 5,102 $ 17,589 $ 3,092 $ 87,887 Provision for credit losses 123 408 663 826 1,744 3,764 Charged-off (589) (1,372) — (253) (409) (2,623) Recoveries 306 514 206 458 210 1,694 ACL balance, September 30, 2022 $ 23,695 $ 37,799 $ 5,971 $ 18,620 $ 4,637 $ 90,722
Schedule of allowance for loan losses and recorded investments in portfolio loans, by category	The following tables present the ACL and amortized cost of portfolio loans by loan category and class (dollars in thousands) : As of September 30, 2023 Portfolio Loans ACL Attributed to Portfolio Loans Collectively Individually Total Collectively Individually Total Portfolio loans and related ACL Commercial loans: Commercial $ 1,937,943 $ 5,506 $ 1,943,449 $ 21,057 $ 1,576 $ 22,633 Commercial real estate 3,352,348 1,405 3,353,753 34,575 116 34,691 Real estate construction 527,598 — 527,598 5,206 — 5,206 Commercial loans and related ACL 5,817,889 6,911 5,824,800 60,838 1,692 62,530 Retail loans: Retail real estate 1,715,359 86 1,715,445 25,308 25 25,333 Retail other 315,915 — 315,915 3,847 — 3,847 Retail loans and related ACL 2,031,274 86 2,031,360 29,155 25 29,180 Portfolio loans and related ACL $ 7,849,163 $ 6,997 $ 7,856,160 $ 89,993 $ 1,717 $ 91,710 As of December 31, 2022 Portfolio Loans ACL Attributed to Portfolio Loans Collectively Individually Total Collectively Individually Total Portfolio loans and related ACL Commercial loans: Commercial $ 1,967,580 $ 6,574 $ 1,974,154 $ 21,384 $ 2,476 $ 23,860 Commercial real estate 3,255,636 6,237 3,261,873 36,299 2,000 38,299 Real estate construction 530,222 247 530,469 6,457 — 6,457 Commercial loans and related ACL 5,753,438 13,058 5,766,496 64,140 4,476 68,616 Retail loans: Retail real estate 1,654,493 2,589 1,657,082 18,168 25 18,193 Retail other 302,124 — 302,124 4,799 — 4,799 Retail loans and related ACL 1,956,617 2,589 1,959,206 22,967 25 22,992 Portfolio loans and related ACL $ 7,710,055 $ 15,647 $ 7,725,702 $ 87,107 $ 4,501 $ 91,608

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2023
Leases [Abstract]
Summary of lease-related balances	The following table summarizes lease-related information and balances reported in our Consolidated Balance Sheets (Unaudited) for the periods presented (dollars in thousands) : As of September 30, December 31, Lease balances Right of use assets $ 11,500 $ 12,829 Lease liabilities 11,783 12,995 Supplemental information Year through which lease terms extend 2037 2037 Weighted average remaining lease term, in years 8.49 8.90 Weighted average discount rate 3.56 % 3.45 %
Schedule of lease costs and other lease information	The following table represents lease costs and cash flows related to leases for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Lease costs Operating lease costs $ 615 $ 563 $ 1,836 $ 1,762 Variable lease costs 9 214 27 436 Short-term lease costs 15 5 37 15 Total lease cost 1 $ 639 $ 782 $ 1,900 $ 2,213 Cash flows related to leases Cash paid for amounts included in the measurement of lease liabilities: Operating lease cash flows – Fixed payments $ 586 $ 1,076 $ 1,720 $ 2,445 Operating lease cash flows – Liability reduction 483 464 1,423 1,741 Right of use assets obtained during the period in exchange for operating lease liabilities 199 1,127 208 1,182 ___________________________________________ 1. Lease costs are included in net occupancy and equipment expense in the Consolidated Statements of Income (Unaudited).
Schedule of future undiscounted lease payments	Busey was obligated under noncancelable operating leases for office space and other commitments, as follows (dollars in thousands) : As of Rent commitments Remainder of 2023 $ 566 2024 2,044 2025 1,764 2026 1,442 2027 1,276 2028 1,255 Thereafter 5,478 Total undiscounted cash flows 13,825 Less: Amounts representing interest 2,042 Present value of net future minimum lease payments $ 11,783
Summary of revenue recorded in connection with leases	Revenues recorded in connection with these leases, reported in Other income on our Consolidated Statements of Income (Unaudited), are summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Rental income $ 152 $ 146 $ 526 $ 519

Deposits (Tables)

Deposits (Tables)	9 Months Ended
	Sep. 30, 2023
Deposits [Abstract]
Schedule of composition of deposits	The composition of Busey’s deposits is as follows (dollars in thousands) : As of September 30, December 31, Deposits Noninterest-bearing demand deposits $ 2,918,574 $ 3,393,666 Interest-bearing transaction deposits 2,856,192 2,857,818 Saving deposits and money market deposits 2,890,944 2,964,421 Time deposits 1,666,652 855,375 Total deposits $ 10,332,362 $ 10,071,280 Additional information about Busey’s deposits follows (dollars in thousands) : As of September 30, December 31, Brokered savings deposits and money market deposits $ 6,055 $ 1,303 Brokered time deposits 283 275 Aggregate amount of time deposits with a minimum denomination of $100,000 976,513 416,445 Aggregate amount of time deposits with a minimum denomination that meets or exceeds the FDIC insurance limit of $250,000 350,276 120,377
Schedule of maturities of time deposits	Scheduled maturities of time deposits are as follows (dollars in thousands) : As of Time deposits by schedule of maturities Remainder of 2023 $ 251,302 2024 1,322,335 2025 52,337 2026 19,438 2027 12,888 2028 7,813 Thereafter 539 Time deposits $ 1,666,652

Borrowings (Tables)

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Schedule of distribution of securities sold under agreements to repurchase and short-term borrowings and weighted average interest rates	Securities sold under agreements to repurchase were as follows (dollars in thousands) : As of September 30, December 31, Securities sold under agreements to repurchase $ 183,702 $ 229,806 Weighted average rate for securities sold under agreements to repurchase 3.07 % 1.91 %
Schedule of short-term borrowings	Short-term borrowings are summarized as follows (dollars in thousands) : As of September 30, December 31, Short-term borrowings FHLB advances maturing in less than one year from date of origination, and the current portion of long-term FHLB advances due within 12 months $ — $ 339,054 Term Loan, current portion due within 12 months 12,000 12,000 Total short-term debt $ 12,000 $ 351,054
Summary of long-term debt	Long-term debt is summarized as follows (dollars in thousands) : As of September 30, December 31, Long-term debt Term Loan $ 21,000 $ 30,000 Total long-term debt $ 21,000 $ 30,000
Schedule of unamortized debt issuance cost	Unamortized debt issuance costs related to senior notes and subordinated notes are presented in the following table (dollars in thousands) : As of September 30, December 31, Unamortized debt issuance costs Subordinated notes issued in 2020 $ 859 $ 1,220 Subordinated notes issued in 2022 1,475 1,742 Total unamortized debt issuance costs $ 2,334 $ 2,962

Regulatory Capital (Tables)

Regulatory Capital (Tables)	9 Months Ended
	Sep. 30, 2023
Banking and Thrift, Other Disclosure [Abstract]
Schedule of applicable holding company and bank regulatory capital requirements	The following tables summarize regulatory capital requirements applicable to First Busey Corporation and Busey Bank (dollars in thousands) : As of September 30, 2023 Actual Minimum Minimum Amount Ratio Amount Ratio Amount Ratio Common equity Tier 1 capital to risk weighted assets First Busey $ 1,144,403 12.52 % $ 411,165 4.50 % $ 593,905 6.50 % Busey Bank $ 1,356,565 14.89 % $ 409,979 4.50 % $ 592,192 6.50 % Tier 1 capital to risk weighted assets First Busey $ 1,218,403 13.33 % $ 548,220 6.00 % $ 730,960 8.00 % Busey Bank $ 1,356,565 14.89 % $ 546,639 6.00 % $ 728,852 8.00 % Total capital to risk weighted assets First Busey $ 1,527,627 16.72 % $ 730,960 8.00 % $ 913,700 10.00 % Busey Bank $ 1,440,789 15.81 % $ 728,852 8.00 % $ 911,064 10.00 % Leverage ratio of Tier 1 capital to average assets First Busey $ 1,218,403 10.08 % $ 483,272 4.00 % N/A N/A Busey Bank $ 1,356,565 11.26 % $ 481,856 4.00 % $ 602,321 5.00 % As of December 31, 2022 Actual Minimum Minimum Amount Ratio Amount Ratio Amount Ratio Common equity Tier 1 capital to risk weighted assets First Busey $ 1,081,686 11.96 % $ 406,980 4.50 % $ 587,861 6.50 % Busey Bank $ 1,306,716 14.49 % $ 405,736 4.50 % $ 586,063 6.50 % Tier 1 capital to risk weighted assets First Busey $ 1,155,686 12.78 % $ 542,640 6.00 % $ 723,521 8.00 % Busey Bank $ 1,306,716 14.49 % $ 540,981 6.00 % $ 721,308 8.00 % Total capital to risk weighted assets First Busey $ 1,457,994 16.12 % $ 723,521 8.00 % $ 904,401 10.00 % Busey Bank $ 1,384,024 15.35 % $ 721,308 8.00 % $ 901,635 10.00 % Leverage ratio of Tier 1 capital to average assets First Busey $ 1,155,686 9.45 % $ 489,124 4.00 % N/A N/A Busey Bank $ 1,306,716 10.72 % $ 487,541 4.00 % $ 609,426 5.00 %

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Summary of changes in the Company's stock option awards	Busey has outstanding stock options assumed from acquisitions. A summary of the status of, and changes in, the Company's stock option awards for the nine months ended September 30, 2023, follows: Shares Weighted- Weighted- Options outstanding at December 31, 2022 26,106 $ 23.53 3.88 Forfeited (4,180) 23.53 Options outstanding at September 30, 2023 21,926 23.53 3.13 Options exercisable at September 30, 2023 21,926 23.53 3.13
Summary of changes in the Company's RSU, PSU, and DSU awards	A summary of changes in Busey’s RSU awards for the nine months ended September 30, 2023, is as follows: RSU Awards Shares Weighted- Nonvested at December 31, 2022 1,096,931 $ 23.61 Granted 224,316 20.44 Dividend equivalents earned 43,841 20.53 Vested (150,806) 29.91 Forfeited (14,145) 22.00 Nonvested at September 30, 2023 1,200,137 22.13 A summary of changes in Busey’s PSU awards for the nine months ended September 30, 2023, is as follows: PSU Awards Shares 1 Weighted- Nonvested at December 31, 2022 285,351 $ 25.40 Granted 224,331 20.04 Dividend equivalents earned 92 22.85 Vested (13,155) 25.50 Forfeited (40,159) 24.98 Nonvested at September 30, 2023 456,460 22.80 Vested and outstanding at September 30, 2023² 13,063 25.52 ___________________________________________ 1. Shares for PSU awards represent target shares at the grant date. 2. Reported at target, as performance determination and settlement activity will take place in the fourth quarter of 2023. A summary of changes in Busey’s DSU awards for the nine months ended September 30, 2023, is as follows: DSU Awards Shares Weighted- Nonvested at December 31, 2022 31,085 $ 25.75 Granted 41,548 20.44 Dividend equivalents earned 6,010 20.48 Vested (36,078) 25.04 Forfeited (73) 20.44 Nonvested at September 30, 2023 42,492 20.42 Vested and outstanding at September 30, 2023 142,347 23.58
Schedule of Stock-based compensation expense	Busey recognized compensation expense related to nonvested RSU, PSU, and DSU awards, as well as the 2021 ESPP, as summarized in the table below (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Stock-based compensation expense RSU awards $ 1,177 $ 1,072 $ 3,428 $ 3,521 PSU awards 1 1,180 1,172 2,724 2,342 DSU awards 213 196 620 679 2021 ESPP 33 36 156 179 Total stock-based compensation expense $ 2,603 $ 2,476 $ 6,928 $ 6,721 ___________________________________________ 1. Expense for PSU awards with a market-based total stockholder return performance goal represents amounts based on target shares at the grant date. Expense for PSU awards with return on average tangible common equity and compounded annual revenue growth rate performance goals represents amounts based on target shares at the grant date, adjusted for performance expectations as of the date indicated.
Schedule of Unamortized stock-based compensation expense	Unamortized compensation expense related to nonvested RSU, PSU, and DSU awards is summarized in the table below (dollars in thousands) : As of September 30, December 31, Unamortized stock-based compensation RSU awards $ 9,437 $ 8,570 PSU awards 1 5,942 4,279 DSU awards 403 175 Total unamortized stock-based compensation $ 15,782 $ 13,024 Weighted average period over which expense is to be recognized 2.5 years 2.5 years ___________________________________________ 1. Unamortized expense for PSU awards with a market-based total stockholder return performance goal represents amounts based on target shares at grant date. Unamortized expense for PSU awards with return on average tangible common equity and compounded annual revenue growth rate performance goals represents amounts based on target shares at grant date, adjusted for performance expectations as of the date indicated.

Outstanding Commitments and C_2

Outstanding Commitments and Contingent Liabilities (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of contractual amount of exposure to off-balance-sheet risk	A summary of the contractual amount of Busey’s exposure to off-balance-sheet risk relating to the Company’s commitments to extend credit and standby letters of credit follows (dollars in thousands) : As of September 30, December 31, Financial instruments whose contract amounts represent credit risk Commitments to extend credit $ 2,130,938 $ 1,991,769 Standby letters of credit 36,847 33,008 Total commitments $ 2,167,785 $ 2,024,777

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of financial instruments owned and pledged as collateral	Busey had loans pledged to the FHLB and Federal Reserve for liquidity as set forth in the table below (dollars in thousands) : As of September 30, December 31, Pledged loans FHLB $ 4,852,634 $ 5,095,448 Federal Reserve Bank 858,312 804,718 Total pledged loans $ 5,710,946 $ 5,900,166 To secure its obligations under derivative contracts, Busey pledged cash and held collateral as follows (dollars in thousands) : As of September 30, December 31, Cash pledged to secure obligations under derivative contracts $ 34,210 $ 38,609 Collateral held to secure obligations under derivative contracts 34,620 29,830
Summary of the interest-rate swaps designated as cash flow hedges	A summary of the interest-rate swaps designated as cash flow hedges is presented below (dollars in thousands) : As of Location September 30, December 31, Debt Swap Notional amount $ 50,000 $ 50,000 Weighted average fixed pay rates 1.79 % 1.79 % Weighted average variable 3-month LIBOR receive rates 5.55 % 4.77 % Weighted average maturity 0.96 years 1.71 years Loan Swap Notional amount $ 300,000 $ 300,000 Weighted average fixed receive rates 4.81 % 4.81 % Weighted average variable Prime pay rates 8.50 % 7.32 % Weighted average maturity 5.35 years 6.10 years Gross aggregate fair value of the swaps Gross aggregate fair value of swap assets Other assets $ 1,886 $ 2,535 Gross aggregate fair value of swap liabilities Other liabilities 37,725 32,367 Balances carried in AOCI Unrealized gains (losses) on cash flow hedges, net of tax AOCI $ (25,092) $ (20,985)
Reclassification of unrealized gains and losses from OCI	Busey expects to reclassify unrealized gains and losses from OCI to interest income and interest expense as shown in the following table, during the next 12 months (dollars in thousands) . Amounts actually recognized could differ from these expectations due to changes in interest rates, hedge de-designations, and the addition of other hedges subsequent to September 30, 2023. As of Unrealized gains (losses) in OCI expected to be recognized in income Unrealized losses expected to be reclassified from OCI to interest income $ (922) Unrealized gains expected to be reclassified from OCI to interest expense 481 Net unrealized gains (losses) in OCI expected to be recognized in net interest income $ (441)
Schedule of interest income (expense) recorded on swap transactions	Interest expense recorded on these swap transactions was as follows for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Interest on swap transactions Increase (decrease) in interest income on swap transactions $ (2,771) $ (405) $ (7,500) $ 947 (Increase) decrease in interest expense on swap transactions 481 35 1,268 (250) Net increase (decrease) in net interest income on swap transactions $ (2,290) $ (370) $ (6,232) $ 697
Summary of Net gains (losses) relating to these derivative instruments	The following table reflects the net gains (losses) relating to cash flow derivative instruments that were recorded in AOCI and the Consolidated Statements of Income (Unaudited) during the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Unrealized gains (losses) on cash flow hedges Net gain (loss) recognized in OCI, net of tax $ (5,577) $ (10,192) $ (8,563) $ (21,587) (Gain) loss reclassified from OCI to interest income, net of tax 1,982 (24) 5,362 (992) (Gain) loss reclassified from OCI to interest expense, net of tax (344) 290 (906) 494 Net change in unrealized gains (losses) on cash flow hedges, net of tax $ (3,939) $ (9,926) $ (4,107) $ (22,085) Changes in fair value of these derivative assets and liabilities are recorded in noninterest expense in the Consolidated Statements of Income (Unaudited) and summarized as follows (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, Location 2023 2022 2023 2022 Interest rate swaps Pay floating, receive fixed Noninterest expense $ 9,007 $ 18,317 $ 4,646 $ 21,792 Pay fixed, receive floating Noninterest expense (9,007) (18,317) (4,646) (21,792) Net change in fair value of interest rate swaps $ — $ — $ — $ — Net gains (losses) relating to these derivative instruments are summarized as follows for the periods presented (dollars in thousands) : Three Months Ended September 30, Nine Months Ended September 30, Location 2023 2022 2023 2022 Net gains (losses) Interest rate lock commitments Mortgage revenue $ (16) $ (111) $ (28) $ 38 Forward sales commitments Mortgage revenue 60 295 92 82 Net gains (losses) $ 44 $ 184 $ 64 $ 120
Summary of fair values of derivative assets and liabilities recorded in consolidated balance sheet	Amounts and fair values of derivative assets and liabilities related to customer interest rate swaps recorded in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 Derivative Asset Derivative Liability Notional Fair Notional Fair Derivatives not designated as hedging instruments Interest rate swaps – pay floating, receive fixed $ 9,320 $ 99 $ 618,971 $ 44,914 Interest rate swaps – pay fixed, receive floating 618,971 44,914 9,320 99 Total derivatives not designated as hedging instruments $ 628,291 $ 45,013 $ 628,291 $ 45,013 As of December 31, 2022 Derivative Asset Derivative Liability Notional Fair Notional Fair Derivatives not designated as hedging instruments Interest rate swaps – pay floating, receive fixed $ 48,728 $ 370 $ 528,183 $ 39,685 Interest rate swaps – pay fixed, receive floating 528,183 39,685 48,728 370 Total derivatives not designated as hedging instruments $ 576,911 $ 40,055 $ 576,911 $ 40,055 Amounts and fair values of mortgage banking derivatives included in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 As of December 31, 2022 Location Notional Fair Notional Fair Derivatives with positive fair value Interest rate lock commitments Other assets $ 715 $ 4 $ 1,517 $ 16 Forward sales commitments Other assets 3,249 66 83 1 Mortgage banking derivatives recorded in other assets $ 3,964 $ 70 $ 1,600 $ 17 Derivatives with negative fair value Interest rate lock commitments Other liabilities $ 1,366 $ 16 $ 83 $ 1 Forward sales commitments Other liabilities 1,795 12 2,757 39 Mortgage banking derivatives recorded in other liabilities $ 3,161 $ 28 $ 2,840 $ 40
Schedule of notional amount and fair value of risk participation agreement	The risk participation agreements mature between 2024 and 2029, and are summarized as follows (dollars in thousands) : As of September 30, December 31, Risk participation agreements purchased Number of risk participation agreements 3 2 Notional amount $ 34,274 $ 18,899 Fair value 7 5 Risk participation agreements sold Number of risk participation agreements 1 — Notional amount $ 20,001 — Fair value — —
Summary of Foreign Currency Forward Contracts	Amounts and fair values of derivative assets and liabilities related to foreign currency contracts recorded in the Consolidated Balance Sheets (Unaudited) are summarized as follows (dollars in thousands) : As of September 30, 2023 Derivative Asset Derivative Liability Notional Fair Notional Fair Foreign currency forward contracts Foreign currency exchange forward contract (Buy) $ 354 $ 58 $ — $ — Foreign currency exchange forward contract (Sell) — — 344 (48) Total foreign currency forward contracts $ 354 $ 58 $ 344 $ (48)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of financial assets and financial liabilities measured at fair value on a recurring basis	The following tables summarize financial assets and financial liabilities measured at fair value on a recurring basis as of September 30, 2023, and December 31, 2022, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands) : As of September 30, 2023 Level 1 Level 2 Level 3 Total Debt securities available for sale: U.S. Treasury securities $ — $ 50,130 $ — $ 50,130 Obligations of U.S. government corporations and agencies — 9,819 — 9,819 Obligations of states and political subdivisions — 226,797 — 226,797 Asset-backed securities — 479,448 — 479,448 Commercial mortgage-backed securities — 100,300 — 100,300 Residential mortgage-backed securities — 1,088,796 — 1,088,796 Corporate debt securities — 227,551 — 227,551 Equity securities — 8,782 — 8,782 Derivative assets — 47,027 7 47,034 Derivative liabilities — 82,814 — 82,814 As of December 31, 2022 Level 1 Level 2 Level 3 Total Debt securities available for sale: U.S. Treasury securities $ — $ 114,061 $ — $ 114,061 Obligations of U.S. government corporations and agencies — 19,779 — 19,779 Obligations of states and political subdivisions — 257,512 — 257,512 Asset-backed securities — 469,875 — 469,875 Commercial mortgage-backed securities — 108,394 — 108,394 Residential mortgage-backed securities — 1,243,256 — 1,243,256 Corporate debt securities — 248,516 — 248,516 Equity securities — 11,535 — 11,535 Derivative assets — 42,607 5 42,612 Derivative liabilities — 72,462 — 72,462
Schedule of assets and liabilities measured at fair value on a non-recurring basis	The following tables summarize assets and liabilities measured at fair value on a non-recurring basis for the periods presented, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands) : As of September 30, 2023 Level 1 Level 2 Level 3 Total Loans evaluated individually, net of related allowance $ — $ — $ 3,333 $ 3,333 Bank property held for sale with impairment — — 4,286 4,286 As of December 31, 2022 Level 1 Level 2 Level 3 Total Loans evaluated individually, net of related allowance $ — $ — $ 5,345 $ 5,345 Bank property held for sale with impairment — — 7,923 7,923
Schedule of quantitative information about Level 3 fair value measurements	The following table presents additional quantitative information about assets measured at fair value on a non-recurring basis for which the Company has utilized Level 3 inputs to determine fair value (dollars in thousands) : As of September 30, 2023 Fair Value Valuation Unobservable Range Loans evaluated individually, net of related allowance $ 3,333 Appraisal of collateral Appraisal adjustments -10.5% to -100.0% (-34.0)% Bank property held for sale with impairment 4,286 Appraisal of collateral or real estate listing price Appraisal adjustments -6.2% to -64.9% (-38.4)% As of December 31, 2022 Fair Value Valuation Techniques Unobservable Input Range (Weighted Average) Loans evaluated individually, net of related allowance $ 5,345 Appraisal of collateral Appraisal adjustments -22.7% to -100.0% (-45.7)% Bank property held for sale with impairment 7,923 Appraisal of collateral or real estate listing price Appraisal adjustments -0.7% to -70.1% (-35.1)%
Schedule of estimated fair values of financial instruments	Estimated fair values of financial instruments that are not carried at fair value in Busey’s Consolidated Balance Sheets (Unaudited), segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows (dollars in thousands) : As of September 30, 2023 As of December 31, 2022 Carrying Fair Carrying Fair Financial assets Level 1 inputs: Cash and cash equivalents $ 337,919 $ 337,919 $ 227,164 $ 227,164 Level 2 inputs: Debt securities held to maturity 882,614 701,676 918,312 785,295 Loans held for sale 3,051 3,059 1,253 1,276 Accrued interest receivable 47,889 47,889 43,372 43,372 Level 3 inputs: Portfolio loans, net 7,764,450 7,241,479 7,634,094 7,320,422 Mortgage servicing rights 3,870 18,758 5,861 18,284 Other servicing rights 1,675 2,144 1,914 2,331 Financial liabilities Level 2 inputs: Time deposits $ 1,666,652 $ 1,643,625 $ 855,375 $ 830,596 Securities sold under agreements to repurchase 183,702 183,702 229,806 229,806 Short-term borrowings 12,000 12,027 351,054 351,085 Long-term debt 21,000 21,020 30,000 30,052 Junior subordinated debt owed to unconsolidated trusts 71,946 55,662 71,810 59,111 Accrued interest payable 22,761 22,761 3,978 3,978 Level 3 inputs: Subordinated notes, net of unamortized issuance costs 222,666 198,812 222,038 208,562

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of computation of earnings per common share	Earnings per common share have been computed as follows (dollars in thousands, except per share amounts) : Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net income $ 30,666 $ 35,661 $ 96,816 $ 93,924 Weighted average number of common shares outstanding, basic 55,486,700 55,349,547 55,441,980 55,399,424 Dilutive effect of common stock equivalents: Options — 249 — 1,606 Warrants — 1,708 432 1,749 RSU awards 640,714 624,576 638,495 661,173 PSU awards 165,868 81,268 126,787 37,393 DSU awards 16,792 10,414 14,996 14,275 ESPP 5,418 5,402 7,934 8,136 Weighted average number of common shares outstanding, diluted 56,315,492 56,073,164 56,230,624 56,123,756 Basic earnings per common share $ 0.55 $ 0.64 $ 1.75 $ 1.70 Diluted earnings per common share $ 0.54 $ 0.64 $ 1.72 $ 1.67
Schedule of average shares excluded from computation of diluted earnings per common share	Average shares that were excluded from the computation of diluted earnings per common share because their effect would have been anti-dilutive are summarized in the table below for the periods presented: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Anti-dilutive common stock equivalents Options 21,926 — 22,219 10,389 RSU awards — — 52,594 51,883 PSU awards 85,074 160,391 137,918 226,771 Total anti-dilutive common stock equivalents 107,000 160,391 212,731 289,043

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2023
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Alternative [Abstract]
Accumulated other comprehensive income (loss)	The following tables present changes in AOCI by component, net of tax, for the periods indicated (dollars in thousands) : Three Months Ended September 30, 2023 2022 Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized/Unrecognized gains (losses) on debt securities Balance at beginning of period $ (335,359) $ 95,591 $ (239,768) $ (277,310) $ 79,047 $ (198,263) Unrealized holding gains (losses) on debt securities available for sale, net (37,696) 10,746 (26,950) (96,937) 27,631 (69,306) Amounts reclassified from AOCI, net 33 (9) 24 74 (21) 53 Amortization of unrecognized losses on securities transferred to held to maturity 1,476 (420) 1,056 1,806 (515) 1,291 Balance at end of period $ (371,546) $ 105,908 $ (265,638) $ (372,367) $ 106,142 $ (266,225) Unrealized gains (losses) on cash flow hedges Balance at beginning of period $ (29,586) $ 8,433 $ (21,153) $ (17,963) $ 5,119 $ (12,844) Unrealized holding gains (losses) on cash flow hedges, net (7,797) 2,220 (5,577) (14,253) 4,061 (10,192) Amounts reclassified from AOCI, net 2,290 (652) 1,638 370 (104) 266 Balance at end of period $ (35,093) $ 10,001 $ (25,092) $ (31,846) $ 9,076 $ (22,770) Total AOCI $ (406,639) $ 115,909 $ (290,730) $ (404,213) $ 115,218 $ (288,995) Nine Months Ended September 30, 2023 2022 Before Tax Tax Effect Net of Tax Before Tax Tax Effect Net of Tax Unrealized/Unrecognized gains (losses) on debt securities Balance at beginning of period $ (352,878) $ 100,585 $ (252,293) $ (32,272) $ 9,199 $ (23,073) Unrealized holding gains (losses) on debt securities available for sale, net (23,600) 6,728 (16,872) (296,507) 84,519 (211,988) Unrecognized losses on debt securities transferred to held to maturity from available for sale — — — (48,456) 13,812 (34,644) Amounts reclassified from AOCI, net 207 (59) 148 (28) 8 (20) Amortization of unrecognized losses on securities transferred to held to maturity 4,725 (1,346) 3,379 4,896 (1,396) 3,500 Balance at end of period $ (371,546) $ 105,908 $ (265,638) $ (372,367) $ 106,142 $ (266,225) Unrealized gains (losses) on cash flow hedges Balance at beginning of period $ (29,350) $ 8,365 $ (20,985) $ (958) $ 273 $ (685) Unrealized holding gains (losses) on cash flow hedges, net (11,975) 3,412 (8,563) (30,191) 8,604 (21,587) Amounts reclassified from AOCI, net 6,232 (1,776) 4,456 (697) 199 (498) Balance at end of period $ (35,093) $ 10,001 $ (25,092) $ (31,846) $ 9,076 $ (22,770) Total AOCI $ (406,639) $ 115,909 $ (290,730) $ (404,213) $ 115,218 $ (288,995)

Operating Segments and Relate_2

Operating Segments and Related Information (Tables)	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Summary of information relating to operating segments	Following is a summary of selected financial information for the Company’s operating segments. The “other” category included in the tables below consists of the parent company, First Busey Risk Management, and the elimination of intercompany transactions (dollars in thousands) : Goodwill Total Assets As of As of September 30, December 31, September 30, December 31, Operating segment Banking $ 294,773 $ 294,773 $ 12,104,706 $ 12,199,960 Wealth Management 14,108 14,108 98,755 84,082 FirsTech 8,992 8,992 50,689 48,715 Other — — 4,100 3,920 Consolidated total $ 317,873 $ 317,873 $ 12,258,250 $ 12,336,677 Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Net interest income Banking $ 81,794 $ 90,916 $ 254,394 $ 244,820 FirsTech 14 15 41 50 Other (4,017) (4,626) (12,117) (12,581) Total net interest income $ 77,791 $ 86,305 $ 242,318 $ 232,289 Noninterest income Banking $ 11,983 $ 13,559 $ 34,716 $ 42,827 Wealth Management 14,350 12,514 43,993 42,425 FirsTech 5,665 5,578 16,954 16,333 Other (990) (718) (4,795) (3,861) Total noninterest income $ 31,008 $ 30,933 $ 90,868 $ 97,724 Noninterest expense Banking $ 55,172 $ 55,273 $ 163,314 $ 165,220 Wealth Management 8,059 7,682 24,821 23,533 FirsTech 5,245 5,109 16,303 14,601 Other 2,469 2,672 6,115 6,850 Total noninterest expense $ 70,945 $ 70,736 $ 210,553 $ 210,204 Income before income taxes Banking $ 38,241 $ 46,838 $ 123,852 $ 118,663 Wealth Management 6,291 4,832 19,172 18,892 FirsTech 434 484 692 1,782 Other (7,476) (8,016) (23,027) (23,292) Total income before income taxes $ 37,490 $ 44,138 $ 120,689 $ 116,045 Net income Banking $ 31,189 $ 37,082 $ 98,689 $ 94,032 Wealth Management 4,781 3,756 14,571 14,688 FirsTech 317 353 505 1,300 Other (5,621) (5,530) (16,949) (16,096) Total net income $ 30,666 $ 35,661 $ 96,816 $ 93,924

Significant Accounting Polici_3

Significant Accounting Policies (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($) segment	Dec. 31, 2022 USD ($)
Accounting Policies [Abstract]
Total assets | $	$ 12,258,250	$ 12,336,677
Number of operating segments	3
Number of reportable segments	3

Debt Securities - Schedule of A

Debt Securities - Schedule of Amortized Cost, Unrealized Gains and Losses, and Fair Values of Securities Classified as AFS and HTM (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt securities available for sale
Amortized Cost	$ 2,517,294	$ 2,772,453
Gross unrealized gains	99	144
Gross unrealized losses	(334,552)	(311,204)
Fair Value	2,182,841	2,461,393
Debt securities held to maturity
Amortized Cost	882,614	918,312
Gross unrealized gains	0	0
Gross unrealized losses	(180,938)	(133,017)
Fair Value	701,676	785,295
U.S. Treasury securities
Debt securities available for sale
Amortized Cost	51,522	117,805
Gross unrealized gains	0	0
Gross unrealized losses	(1,392)	(3,744)
Fair Value	50,130	114,061
Obligations of U.S. government corporations and agencies
Debt securities available for sale
Amortized Cost	10,071	20,097
Gross unrealized gains	2	3
Gross unrealized losses	(254)	(321)
Fair Value	9,819	19,779
Obligations of states and political subdivisions
Debt securities available for sale
Amortized Cost	254,549	283,481
Gross unrealized gains	6	106
Gross unrealized losses	(27,758)	(26,075)
Fair Value	226,797	257,512
Asset-backed securities
Debt securities available for sale
Amortized Cost	486,517	489,558
Gross unrealized gains	0	0
Gross unrealized losses	(7,069)	(19,683)
Fair Value	479,448	469,875
Commercial mortgage-backed securities
Debt securities available for sale
Amortized Cost	120,117	124,423
Gross unrealized gains	0	0
Gross unrealized losses	(19,817)	(16,029)
Fair Value	100,300	108,394
Debt securities held to maturity
Amortized Cost	459,866	474,820
Gross unrealized gains	0	0
Gross unrealized losses	(93,401)	(63,738)
Fair Value	366,465	411,082
Residential mortgage-backed securities
Debt securities available for sale
Amortized Cost	1,343,324	1,463,971
Gross unrealized gains	0	2
Gross unrealized losses	(254,528)	(220,717)
Fair Value	1,088,796	1,243,256
Debt securities held to maturity
Amortized Cost	422,748	443,492
Gross unrealized gains	0	0
Gross unrealized losses	(87,537)	(69,279)
Fair Value	335,211	374,213
Corporate debt securities
Debt securities available for sale
Amortized Cost	251,194	273,118
Gross unrealized gains	91	33
Gross unrealized losses	(23,734)	(24,635)
Fair Value	$ 227,551	$ 248,516

Debt Securities - Maturity of D

Debt Securities - Maturity of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost
Due in one year or less	$ 109,189
Due after one year through five years	312,419
Due after five years through ten years	431,297
Due after ten years	1,664,389
Amortized Cost	2,517,294	$ 2,772,453
Fair Value
Due in one year or less	106,940
Due after one year through five years	289,027
Due after five years through ten years	389,702
Due after ten years	1,397,172
Fair Value	2,182,841	2,461,393
Amortized Cost
Due after one year through five years	63,474
Due after five years through ten years	40,076
Due after ten years	779,064
Amortized Cost	882,614	918,312
Fair Value
Due after one year through five years	58,144
Due after five years through ten years	34,985
Due after ten years	608,547
Fair Value	$ 701,676	$ 785,295

Debt Securities - Gains and los

Debt Securities - Gains and losses on debt securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Realized gains and losses on debt securities
Gross gains on debt securities	$ 10	$ 0	$ 20	$ 114
Gross (losses) on debt securities	(43)	(74)	(227)	(86)
Realized net gains (losses) on debt securities	$ (33)	$ (74)	$ (207)	$ 28

Debt Securities - Narrative (De

Debt Securities - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Asset Pledged as Collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Debt securities, carrying amount	$ 819.8	$ 746.7

Debt Securities - Debt securiti

Debt Securities - Debt securities in an unrealized loss position (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value
Less than 12 months	$ 49,649	$ 1,070,674
12 months or more	2,122,190	1,368,859
Total	2,171,839	2,439,533
Unrealized Losses
Less than 12 months	(1,237)	(81,841)
Unrealized Losses	(333,315)	(229,363)
Total	(334,552)	(311,204)
Fair Value
Less than 12 months		58,065
12 months or more	701,676	727,230
Total	701,676	785,295
Unrealized Losses
Less than 12 months		(8,009)
12 months or more	(180,938)	(125,008)
Total	(180,938)	(133,017)
U.S. Treasury securities
Fair Value
Less than 12 months	0	74
12 months or more	50,130	113,987
Total	50,130	114,061
Unrealized Losses
Less than 12 months	0	0
Unrealized Losses	(1,392)	(3,744)
Total	(1,392)	(3,744)
Obligations of U.S. government corporations and agencies
Fair Value
Less than 12 months	1,983	19,603
12 months or more	7,699	0
Total	9,682	19,603
Unrealized Losses
Less than 12 months	(6)	(321)
Unrealized Losses	(248)	0
Total	(254)	(321)
Obligations of states and political subdivisions
Fair Value
Less than 12 months	45,778	166,147
12 months or more	177,195	75,217
Total	222,973	241,364
Unrealized Losses
Less than 12 months	(1,219)	(10,059)
Unrealized Losses	(26,539)	(16,016)
Total	(27,758)	(26,075)
Asset-backed securities
Fair Value
Less than 12 months	0	390,164
12 months or more	479,448	79,711
Total	479,448	469,875
Unrealized Losses
Less than 12 months	0	(15,648)
Unrealized Losses	(7,069)	(4,035)
Total	(7,069)	(19,683)
Commercial mortgage-backed securities
Fair Value
Less than 12 months	0	89,428
12 months or more	100,300	18,966
Total	100,300	108,394
Unrealized Losses
Less than 12 months	0	(12,623)
Unrealized Losses	(19,817)	(3,406)
Total	(19,817)	(16,029)
Fair Value
Less than 12 months		58,065
12 months or more	366,465	353,017
Total	366,465	411,082
Unrealized Losses
Less than 12 months		(8,009)
12 months or more	(93,401)	(55,729)
Total	(93,401)	(63,738)
Residential mortgage-backed securities
Fair Value
Less than 12 months	431	366,221
12 months or more	1,088,344	876,668
Total	1,088,775	1,242,889
Unrealized Losses
Less than 12 months	(10)	(38,111)
Unrealized Losses	(254,518)	(182,606)
Total	(254,528)	(220,717)
Fair Value
Less than 12 months		0
12 months or more	335,211	374,213
Total	335,211	374,213
Unrealized Losses
Less than 12 months		0
12 months or more	(87,537)	(69,279)
Total	(87,537)	(69,279)
Corporate debt securities
Fair Value
Less than 12 months	1,457	39,037
12 months or more	219,074	204,310
Total	220,531	243,347
Unrealized Losses
Less than 12 months	(2)	(5,079)
Unrealized Losses	(23,732)	(19,556)
Total	$ (23,734)	$ (24,635)

Debt Securities - Additional In

Debt Securities - Additional Information (Details) $ in Thousands	Sep. 30, 2023 USD ($) security	Dec. 31, 2022 USD ($) security
Available for Sale
Debt securities with gross unrealized or unrecognized losses, fair value | $	$ 2,171,839	$ 2,439,533
Gross unrealized or unrecognized losses on debt securities | $	$ 334,552	$ 311,204
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses	15.40%	12.80%
Count of debt securities | security	1,001	1,091
Count of debt securities in an unrealized or unrecognized loss position | security	982	1,032
Held to Maturity
Debt securities with gross unrealized or unrecognized losses, fair value | $	$ 701,676	$ 785,295
Gross unrealized or unrecognized losses on debt securities | $	$ 180,938	$ 133,017
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses	25.80%	16.90%
Count of debt securities | security	55	55
Count of debt securities in an unrealized or unrecognized loss position | security	55	55
Total
Debt securities with gross unrealized or unrecognized losses, fair value | $	$ 2,873,515	$ 3,224,828
Gross unrealized or unrecognized losses on debt securities | $	$ 515,490	$ 444,221
Ratio of gross unrealized or unrecognized losses to debt securities with gross unrealized or unrecognized losses	17.90%	13.80%
Count of debt securities | security	1,056	1,146
Count of debt securities in an unrealized or unrecognized loss position | security	1,037	1,087

Portfolio Loans- Distribution o

Portfolio Loans- Distribution of portfolio loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	$ 7,856,160		$ 7,725,702
ACL	(91,710)	$ (91,639)	(91,608)	$ (90,722)	$ (88,757)	$ (87,887)
Portfolio loans, net	7,764,450		7,634,094
Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	5,824,800		5,766,496
ACL	(62,530)		(68,616)
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	1,943,449		1,974,154
ACL	(22,633)	(24,510)	(23,860)	(23,695)	(23,359)	(23,855)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	3,353,753		3,261,873
ACL	(34,691)	(33,656)	(38,299)	(37,799)	(37,182)	(38,249)
Real estate construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	527,598		530,469
ACL	(5,206)	(5,071)	(6,457)	(5,971)	(5,669)	(5,102)
Total retail loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	2,031,360		1,959,206
ACL	(29,180)		(22,992)
Retail real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	1,715,445		1,657,082
ACL	(25,333)	(24,675)	(18,193)	(18,620)	(17,984)	(17,589)
Retail other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	315,915		302,124
ACL	$ (3,847)	$ (3,727)	$ (4,799)	$ (4,637)	$ (4,563)	$ (3,092)

Portfolio Loans - Narrative (De

Portfolio Loans - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($) contract	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($) contract	Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net deferred loan origination (fees) costs	$ 13,400,000		$ 13,400,000		$ 14,000,000
Net accretable purchase accounting adjustments			(4,900,000)		(5,900,000)
Gross interest income that would have been recorded if impaired loans had been current	200,000	$ 300,000	900,000	$ 800,000
Amount of interest collected and recognized on a cash basis				$ 400,000
TDRs subsequently classified as non-performing and had payment defaults | contract		0		0
Collateral dependent loans secured by real estate or business assets			10,000,000		14,000,000
Loans in the process of foreclosure	1,000,000		1,000,000
Performing Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring					3,000,000
Nonperforming Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring					500,000
Retail real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans purchased	0	$ 0	0	$ 0
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans designated as TDRs | contract		0		1
Maximum | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit where loans are processed through an expedited underwriting process			1,000,000
Watch | Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit above which loans are annually reviewed			1,000,000
Special Mention | Total commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Limit above which loans are annually reviewed			350,000
PPP Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized cost of the loans outstanding	$ 600,000		$ 600,000		$ 800,000

Portfolio Loans - Schedule of f

Portfolio Loans - Schedule of financial instruments owned and pledged as collateral (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial Instruments Owned and Pledged as Collateral [Line Items]
Portfolio loans, net	$ 7,764,450	$ 7,634,094
Asset Pledged as Collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Portfolio loans, net	5,710,946	5,900,166
FHLB
Financial Instruments Owned and Pledged as Collateral [Line Items]
Portfolio loans, net	4,852,634	5,095,448
Federal Reserve Bank
Financial Instruments Owned and Pledged as Collateral [Line Items]
Portfolio loans, net	$ 858,312	$ 804,718

Portfolio Loans - Summary of ri

Portfolio Loans - Summary of risk grades segregated by category of portfolio loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	$ 7,856,160	$ 7,725,702
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	7,005,508	6,964,678
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	721,586	563,897
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	70,118	91,405
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	47,650	90,655
Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	11,298	15,067
Total commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	5,824,800	5,766,496
Total commercial loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	4,990,971	5,023,108
Total commercial loans | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	711,341	553,377
Total commercial loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	69,476	90,067
Total commercial loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	45,826	88,126
Total commercial loans | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	7,186	11,818
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,943,449	1,974,154
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,533,562	1,668,495
Commercial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	350,820	201,758
Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	24,705	46,540
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	28,734	51,187
Commercial | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	5,628	6,174
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	3,353,753	3,261,873
Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	2,944,191	2,851,709
Commercial real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	351,494	326,455
Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	44,771	43,526
Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	11,739	34,539
Commercial real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,558	5,644
Real estate construction
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	527,598	530,469
Real estate construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	513,218	502,904
Real estate construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	9,027	25,164
Real estate construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	0	1
Real estate construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	5,353	2,400
Real estate construction | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	0	0
Total retail loans
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	2,031,360	1,959,206
Total retail loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	2,014,537	1,941,570
Total retail loans | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	10,245	10,520
Total retail loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	642	1,338
Total retail loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,824	2,529
Total retail loans | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	4,112	3,249
Retail real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,715,445	1,657,082
Retail real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,698,692	1,639,599
Retail real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	10,245	10,520
Retail real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	642	1,338
Retail real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	1,824	2,529
Retail real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	4,042	3,096
Retail other
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	315,915	302,124
Retail other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	315,845	301,971
Retail other | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	0	0
Retail other | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	0	0
Retail other | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	0	0
Retail other | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Commercial loans	$ 70	$ 153

Portfolio Loans - Risk grades o

Portfolio Loans - Risk grades of portfolio loans, further sorted by origination year (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	$ 1,305,716	$ 2,288,440
2023, charge-off	4
2022 / 2021	1,877,528	1,926,481
2022, charge-off	76
2021 / 2020	1,647,750	962,405
2021, charge-off	577
2020 / 2019	775,934	558,294
2020, charge-off	30
2019 / 2018	498,204	323,245
2019, charge-off	617
Prior	771,673	644,140
Prior, charge-off	2,339
Revolving Loans	979,355	1,022,697
Revolving Loans, charge-off	0
Total	7,856,160	7,725,702
Total, gross write-offs	3,643
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total	7,005,508	6,964,678
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total	721,586	563,897
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total	70,118	91,405
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total	47,650	90,655
Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total	11,298	15,067
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	401,852	544,993
2023, charge-off	0
2022 / 2021	316,757	320,898
2022, charge-off	0
2021 / 2020	230,222	142,171
2021, charge-off	420
2020 / 2019	101,371	67,027
2020, charge-off	0
2019 / 2018	51,586	55,404
2019, charge-off	316
Prior	186,358	159,475
Prior, charge-off	997
Revolving Loans	655,303	684,186
Revolving Loans, charge-off	0
Total	1,943,449	1,974,154
Total, gross write-offs	1,733
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	279,467	479,893
2022 / 2021	255,619	266,122
2021 / 2020	181,603	136,445
2020 / 2019	74,600	52,046
2019 / 2018	39,483	50,764
Prior	152,523	135,000
Revolving Loans	550,267	548,225
Total	1,533,562	1,668,495
Commercial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	112,285	54,195
2022 / 2021	59,685	49,382
2021 / 2020	44,244	3,288
2020 / 2019	25,119	7,201
2019 / 2018	7,526	1,258
Prior	24,532	2,160
Revolving Loans	77,429	84,274
Total	350,820	201,758
Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	616	1,958
2022 / 2021	541	937
2021 / 2020	651	1,642
2020 / 2019	1,104	974
2019 / 2018	499	1,000
Prior	6,937	17,024
Revolving Loans	14,357	23,005
Total	24,705	46,540
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	8,901	8,926
2022 / 2021	912	1,165
2021 / 2020	1,119	570
2020 / 2019	445	6,671
2019 / 2018	3,948	2,382
Prior	1,859	5,191
Revolving Loans	11,550	26,282
Total	28,734	51,187
Commercial | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	583	21
2022 / 2021	0	3,292
2021 / 2020	2,605	226
2020 / 2019	103	135
2019 / 2018	130	0
Prior	507	100
Revolving Loans	1,700	2,400
Total	5,628	6,174
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	456,269	978,317
2023, charge-off	0
2022 / 2021	898,639	898,122
2022, charge-off	0
2021 / 2020	862,943	558,607
2021, charge-off	0
2020 / 2019	444,723	397,516
2020, charge-off	0
2019 / 2018	366,956	201,813
2019, charge-off	239
Prior	300,836	209,715
Prior, charge-off	936
Revolving Loans	23,387	17,783
Revolving Loans, charge-off	0
Total	3,353,753	3,261,873
Total, gross write-offs	1,175
Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	352,661	883,688
2022 / 2021	850,371	819,133
2021 / 2020	778,662	478,452
2020 / 2019	404,109	297,525
2019 / 2018	281,889	161,409
Prior	258,207	198,419
Revolving Loans	18,292	13,083
Total	2,944,191	2,851,709
Commercial real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	82,748	77,346
2022 / 2021	45,945	56,113
2021 / 2020	69,450	64,282
2020 / 2019	33,694	96,664
2019 / 2018	79,906	21,592
Prior	34,700	5,758
Revolving Loans	5,051	4,700
Total	351,494	326,455
Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	18,753	11,943
2022 / 2021	1,597	5,389
2021 / 2020	13,762	12,386
2020 / 2019	3,908	1,420
2019 / 2018	3,330	6,917
Prior	3,421	5,471
Revolving Loans	0	0
Total	44,771	43,526
Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	1,882	5,340
2022 / 2021	193	13,528
2021 / 2020	904	3,454
2020 / 2019	2,987	1,907
2019 / 2018	1,831	10,248
Prior	3,898	62
Revolving Loans	44	0
Total	11,739	34,539
Commercial real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	225	0
2022 / 2021	533	3,959
2021 / 2020	165	33
2020 / 2019	25	0
2019 / 2018	0	1,647
Prior	610	5
Revolving Loans	0	0
Total	1,558	5,644
Real estate construction
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	159,315	230,042
2022 / 2021	176,353	203,743
2021 / 2020	105,216	71,184
2020 / 2019	58,157	1,539
2019 / 2018	1,407	1,901
Prior	3,899	3,149
Revolving Loans	23,251	18,911
Total	527,598	530,469
Real estate construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	152,897	219,112
2022 / 2021	171,900	191,724
2021 / 2020	104,963	68,015
2020 / 2019	54,943	1,490
2019 / 2018	1,365	1,901
Prior	3,899	1,751
Revolving Loans	23,251	18,911
Total	513,218	502,904
Real estate construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	1,065	8,530
2022 / 2021	4,453	12,019
2021 / 2020	253	3,169
2020 / 2019	3,214	48
2019 / 2018	42	0
Prior	0	1,398
Revolving Loans	0	0
Total	9,027	25,164
Real estate construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022		0
2022 / 2021		0
2021 / 2020		0
2020 / 2019		1
2019 / 2018		0
Prior		0
Revolving Loans		0
Total	0	1
Real estate construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	5,353	2,400
2022 / 2021	0	0
2021 / 2020	0	0
2020 / 2019	0	0
2019 / 2018	0	0
Prior	0	0
Revolving Loans	0	0
Total	5,353	2,400
Real estate construction | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0	0
Retail real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	202,184	400,507
2023, charge-off	0
2022 / 2021	382,882	460,072
2022, charge-off	5
2021 / 2020	423,392	177,299
2021, charge-off	0
2020 / 2019	163,508	79,126
2020, charge-off	29
2019 / 2018	71,864	58,481
2019, charge-off	62
Prior	279,040	270,808
Prior, charge-off	156
Revolving Loans	192,575	210,789
Revolving Loans, charge-off	0
Total	1,715,445	1,657,082
Total, gross write-offs	252
Retail real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	201,140	396,547
2022 / 2021	379,512	456,158
2021 / 2020	420,164	175,148
2020 / 2019	162,295	77,569
2019 / 2018	71,102	56,887
Prior	274,617	267,387
Revolving Loans	189,862	209,903
Total	1,698,692	1,639,599
Retail real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	767	2,928
2022 / 2021	2,704	2,991
2021 / 2020	2,877	1,846
2020 / 2019	973	1,444
2019 / 2018	579	1,063
Prior	596	27
Revolving Loans	1,749	221
Total	10,245	10,520
Retail real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	204	945
2022 / 2021	55	0
2021 / 2020	0	0
2020 / 2019	0	0
2019 / 2018	0	0
Prior	383	393
Revolving Loans	0	0
Total	642	1,338
Retail real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	73	77
2022 / 2021	73	732
2021 / 2020	295	198
2020 / 2019	53	81
2019 / 2018	82	141
Prior	1,010	1,293
Revolving Loans	238	7
Total	1,824	2,529
Retail real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	0	10
2022 / 2021	538	191
2021 / 2020	56	107
2020 / 2019	187	32
2019 / 2018	101	390
Prior	2,434	1,708
Revolving Loans	726	658
Total	4,042	3,096
Retail other
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	86,096	134,581
2023, charge-off	4
2022 / 2021	102,897	43,646
2022, charge-off	71
2021 / 2020	25,977	13,144
2021, charge-off	157
2020 / 2019	8,175	13,086
2020, charge-off	1
2019 / 2018	6,391	5,646
2019, charge-off	0
Prior	1,540	993
Prior, charge-off	250
Revolving Loans	84,839	91,028
Revolving Loans, charge-off	0
Total	315,915	302,124
Total, gross write-offs	483
Retail other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	86,096	134,567
2022 / 2021	102,834	43,512
2021 / 2020	25,977	13,141
2020 / 2019	8,172	13,086
2019 / 2018	6,388	5,646
Prior	1,539	991
Revolving Loans	84,839	91,028
Total	315,845	301,971
Retail other | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0	0
Retail other | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0	0
Retail other | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0	0
Retail other | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
2023 / 2022	0	14
2022 / 2021	63	134
2021 / 2020	0	3
2020 / 2019	3	0
2019 / 2018	3	0
Prior	1	2
Revolving Loans	0	0
Total	$ 70	$ 153

Portfolio Loans -Summary of por

Portfolio Loans -Summary of portfolio loans that are past due and still accruing or on a non-accrual status (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Commercial loans	$ 7,856,160	$ 7,725,702
90 days past due and still accruing	709	673
Non-accrual Loans	11,298	15,067
30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	4,557	5,249
60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	1,377	1,299
Past due and non-accrual commercial loans
Financing Receivable, Past Due [Line Items]
Commercial loans	5,824,800	5,766,496
90 days past due and still accruing	51	0
Non-accrual Loans	7,186	11,818
Past due and non-accrual commercial loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	0	126
Past due and non-accrual commercial loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	465	0
Commercial
Financing Receivable, Past Due [Line Items]
Commercial loans	1,943,449	1,974,154
90 days past due and still accruing	51	0
Non-accrual Loans	5,628	6,174
Commercial | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	0	2
Commercial | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	112	0
Commercial real estate
Financing Receivable, Past Due [Line Items]
Commercial loans	3,353,753	3,261,873
90 days past due and still accruing	0	0
Non-accrual Loans	1,558	5,644
Commercial real estate | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	0	124
Commercial real estate | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	109	0
Real estate construction
Financing Receivable, Past Due [Line Items]
Commercial loans	527,598	530,469
90 days past due and still accruing	0
Non-accrual Loans	0
Real estate construction | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	0
Real estate construction | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	244
Past due and non-accrual retail loans
Financing Receivable, Past Due [Line Items]
Commercial loans	2,031,360	1,959,206
90 days past due and still accruing	658	673
Non-accrual Loans	4,112	3,249
Past due and non-accrual retail loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	4,557	5,123
Past due and non-accrual retail loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	912	1,299
Retail real estate
Financing Receivable, Past Due [Line Items]
Commercial loans	1,715,445	1,657,082
90 days past due and still accruing	558	673
Non-accrual Loans	4,042	3,096
Retail real estate | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	3,643	4,709
Retail real estate | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	840	1,239
Retail other
Financing Receivable, Past Due [Line Items]
Commercial loans	315,915	302,124
90 days past due and still accruing	100	0
Non-accrual Loans	70	153
Retail other | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	914	414
Retail other | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Commercial loans	$ 72	$ 60

Portfolio Loans - Schedule of l

Portfolio Loans - Schedule of loan modifications made to borrowers experiencing financial difficulty (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
Interest Rate Reduction
Loans identified as impaired
Amortized cost basis	$ 880	$ 880
% of Total Class of Financing Receivable	0%	0%
Interest Rate Reduction | Commercial
Loans identified as impaired
Amortized cost basis	$ 0	$ 0
% of Total Class of Financing Receivable	0%	0%
Interest Rate Reduction | Commercial real estate
Loans identified as impaired
Amortized cost basis	$ 880	$ 880
% of Total Class of Financing Receivable	0%	0%
Interest Rate Reduction | Real estate construction
Loans identified as impaired
Amortized cost basis		$ 0
% of Total Class of Financing Receivable		0%
Payment Deferral
Loans identified as impaired
Amortized cost basis		$ 225
% of Total Class of Financing Receivable		0%
Payment Deferral | Commercial
Loans identified as impaired
Amortized cost basis		$ 0
% of Total Class of Financing Receivable		0%
Payment Deferral | Commercial real estate
Loans identified as impaired
Amortized cost basis		$ 225
% of Total Class of Financing Receivable		0%
Payment Deferral | Real estate construction
Loans identified as impaired
Amortized cost basis		$ 0
% of Total Class of Financing Receivable		0%
Term Extension
Loans identified as impaired
Amortized cost basis	$ 12,579	$ 23,690
% of Total Class of Financing Receivable	0.20%	0.30%
Term Extension | Commercial
Loans identified as impaired
Amortized cost basis	$ 12,026	$ 17,334
% of Total Class of Financing Receivable	0.60%	0.90%
Term Extension | Commercial real estate
Loans identified as impaired
Amortized cost basis	$ 553	$ 1,003
% of Total Class of Financing Receivable	0%	0%
Term Extension | Real estate construction
Loans identified as impaired
Amortized cost basis		$ 5,353
% of Total Class of Financing Receivable		1%

Portfolio Loans - Summary of th

Portfolio Loans - Summary of the financial effect of modifications (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
Loans identified as impaired
Weighted Average Interest Rate Reduction	2.50%	2.50%
Weighted Average Term Extension	15 months	13 months 21 days
Commercial
Loans identified as impaired
Weighted Average Term Extension	15 months 9 days	14 months 9 days
Commercial real estate
Loans identified as impaired
Weighted Average Interest Rate Reduction	2.50%	2.50%
Weighted Average Term Extension	9 months	11 months 6 days
Real estate construction
Loans identified as impaired
Weighted Average Term Extension		12 months

Portfolio Loans - Schedule of t

Portfolio Loans - Schedule of the amortized cost basis of modified financing receivables that subsequently defaulted (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)
Payment Deferral
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	$ 225
Term Extension
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	500
Commercial | Payment Deferral
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	0
Commercial | Term Extension
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	500
Commercial real estate | Payment Deferral
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	225
Commercial real estate | Term Extension
Loans identified as impaired
Amortized cost of modified loans with subsequent defaults	$ 0

Portfolio Loans - Schedule of p

Portfolio Loans - Schedule of payment status of modified loans (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Loans identified as impaired
Non-accrual	$ 725
Current
Loans identified as impaired
Amortized cost of modified loans	24,070
Commercial
Loans identified as impaired
Non-accrual	500
Commercial | Current
Loans identified as impaired
Amortized cost of modified loans	16,834
Commercial real estate
Loans identified as impaired
Non-accrual	225
Commercial real estate | Current
Loans identified as impaired
Amortized cost of modified loans	1,883
Real estate construction
Loans identified as impaired
Non-accrual	0
Real estate construction | Current
Loans identified as impaired
Amortized cost of modified loans	$ 5,353

Portfolio Loans - Schedule of d

Portfolio Loans - Schedule of details of impaired loans, segregated by category (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	$ 14,166	$ 20,608
Recorded investment with no allowance	1,947	5,801
Recorded investment with allowance	5,050	9,846
Total recorded investment	6,997	15,647
Related Allowance	1,717	4,501
Average Recorded Investment	12,220	14,551
Total commercial loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	13,953	17,875
Recorded investment with no allowance	1,886	3,237
Recorded investment with allowance	5,025	9,821
Total recorded investment	6,911	13,058
Related Allowance	1,692	4,476
Average Recorded Investment	11,024	12,240
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	10,007	9,589
Recorded investment with no allowance	597	656
Recorded investment with allowance	4,909	5,918
Total recorded investment	5,506	6,574
Related Allowance	1,576	2,476
Average Recorded Investment	6,058	6,761
Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	3,946	8,039
Recorded investment with no allowance	1,289	2,334
Recorded investment with allowance	116	3,903
Total recorded investment	1,405	6,237
Related Allowance	116	2,000
Average Recorded Investment	4,866	5,219
Real estate construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	0	247
Recorded investment with no allowance	0	247
Recorded investment with allowance	0	0
Total recorded investment	0	247
Related Allowance	0	0
Average Recorded Investment	100	260
Total retail loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	213	2,733
Recorded investment with no allowance	61	2,564
Recorded investment with allowance	25	25
Total recorded investment	86	2,589
Related Allowance	25	25
Average Recorded Investment	1,196	2,311
Retail real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Unpaid Principal Balance	213	2,733
Recorded investment with no allowance	61	2,564
Recorded investment with allowance	25	25
Total recorded investment	86	2,589
Related Allowance	25	25
Average Recorded Investment	$ 1,196	$ 2,311

Portfolio Loans - Schedule of a

Portfolio Loans - Schedule of activity on the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Activity in the allowance for loan losses
ACL beginning balance	$ 91,639	$ 88,757	$ 91,608	$ 87,887
Provision for credit losses	364	2,364	1,944	3,764
Charged-off	(1,115)	(819)	(3,643)	(2,623)
Recoveries	822	420	1,801	1,694
ACL ending balance	91,710	90,722	91,710	90,722
Commercial
Activity in the allowance for loan losses
ACL beginning balance	24,510	23,359	23,860	23,855
Provision for credit losses	(1,306)	615	79	123
Charged-off	(758)	(381)	(1,733)	(589)
Recoveries	187	102	427	306
ACL ending balance	22,633	23,695	22,633	23,695
Commercial real estate
Activity in the allowance for loan losses
ACL beginning balance	33,656	37,182	38,299	38,249
Provision for credit losses	745	598	(3,006)	408
Charged-off	(102)	0	(1,175)	(1,372)
Recoveries	392	19	573	514
ACL ending balance	34,691	37,799	34,691	37,799
Real estate construction
Activity in the allowance for loan losses
ACL beginning balance	5,071	5,669	6,457	5,102
Provision for credit losses	104	216	(1,404)	663
Charged-off	0	0	0	0
Recoveries	31	86	153	206
ACL ending balance	5,206	5,971	5,206	5,971
Retail real estate
Activity in the allowance for loan losses
ACL beginning balance	24,675	17,984	18,193	17,589
Provision for credit losses	674	684	6,975	826
Charged-off	(144)	(220)	(252)	(253)
Recoveries	128	172	417	458
ACL ending balance	25,333	18,620	25,333	18,620
Retail other
Activity in the allowance for loan losses
ACL beginning balance	3,727	4,563	4,799	3,092
Provision for credit losses	147	251	(700)	1,744
Charged-off	(111)	(218)	(483)	(409)
Recoveries	84	41	231	210
ACL ending balance	$ 3,847	$ 4,637	$ 3,847	$ 4,637

Portfolio Loans - Schedule of_2

Portfolio Loans - Schedule of allowance for loan losses and recorded investments in portfolio loans, by category (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Portfolio Loans
Collectively Evaluated for Impairment	$ 7,849,163		$ 7,710,055
Individually Evaluated for Impairment	6,997		15,647
Total	7,856,160		7,725,702
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	89,993		87,107
Individually Evaluated for Impairment	1,717		4,501
Total	91,710	$ 91,639	91,608	$ 90,722	$ 88,757	$ 87,887
Total commercial loans
Portfolio Loans
Collectively Evaluated for Impairment	5,817,889		5,753,438
Individually Evaluated for Impairment	6,911		13,058
Total	5,824,800		5,766,496
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	60,838		64,140
Individually Evaluated for Impairment	1,692		4,476
Total	62,530		68,616
Commercial
Portfolio Loans
Collectively Evaluated for Impairment	1,937,943		1,967,580
Individually Evaluated for Impairment	5,506		6,574
Total	1,943,449		1,974,154
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	21,057		21,384
Individually Evaluated for Impairment	1,576		2,476
Total	22,633	24,510	23,860	23,695	23,359	23,855
Commercial real estate
Portfolio Loans
Collectively Evaluated for Impairment	3,352,348		3,255,636
Individually Evaluated for Impairment	1,405		6,237
Total	3,353,753		3,261,873
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	34,575		36,299
Individually Evaluated for Impairment	116		2,000
Total	34,691	33,656	38,299	37,799	37,182	38,249
Real estate construction
Portfolio Loans
Collectively Evaluated for Impairment	527,598		530,222
Individually Evaluated for Impairment	0		247
Total	527,598		530,469
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	5,206		6,457
Individually Evaluated for Impairment	0		0
Total	5,206	5,071	6,457	5,971	5,669	5,102
Total retail loans
Portfolio Loans
Collectively Evaluated for Impairment	2,031,274		1,956,617
Individually Evaluated for Impairment	86		2,589
Total	2,031,360		1,959,206
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	29,155		22,967
Individually Evaluated for Impairment	25		25
Total	29,180		22,992
Retail real estate
Portfolio Loans
Collectively Evaluated for Impairment	1,715,359		1,654,493
Individually Evaluated for Impairment	86		2,589
Total	1,715,445		1,657,082
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	25,308		18,168
Individually Evaluated for Impairment	25		25
Total	25,333	24,675	18,193	18,620	17,984	17,589
Retail other
Portfolio Loans
Collectively Evaluated for Impairment	315,915		302,124
Individually Evaluated for Impairment	0		0
Total	315,915		302,124
ACL Attributed to Portfolio Loans
Collectively Evaluated for Impairment	3,847		4,799
Individually Evaluated for Impairment	0		0
Total	$ 3,847	$ 3,727	$ 4,799	$ 4,637	$ 4,563	$ 3,092

Leases - Summary of lease-relat

Leases - Summary of lease-related balances (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Leases [Abstract]
Right of use assets	$ 11,500	$ 12,829
Lease liabilities	$ 11,783	$ 12,995
Weighted average remaining lease term, in years	8 years 5 months 26 days	8 years 10 months 24 days
Weighted average discount rate	3.56%	3.45%

Leases - Schedule of lease cost

Leases - Schedule of lease costs and other lease information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Lease costs
Operating lease costs	$ 615	$ 563	$ 1,836	$ 1,762
Variable lease costs	9	214	27	436
Short-term lease costs	15	5	37	15
Total lease cost	639	782	1,900	2,213
Cash flows related to leases
Operating lease cash flows – Fixed payments	586	1,076	1,720	2,445
Operating lease cash flows – Liability reduction	483	464	1,423	1,741
Right of use assets obtained during the period in exchange for operating lease liabilities	$ 199	$ 1,127	$ 208	$ 1,182

Leases - Schedule of future und

Leases - Schedule of future undiscounted lease payments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Rent commitments
Remainder of 2023	$ 566
2024	2,044
2025	1,764
2026	1,442
2027	1,276
2028	1,255
Thereafter	5,478
Total undiscounted cash flows	13,825
Less: Amounts representing interest	2,042
Present value of net future minimum lease payments	$ 11,783	$ 12,995

Leases - Summary of revenue rec

Leases - Summary of revenue recorded in connection with leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Rental income	$ 152	$ 146	$ 526	$ 519

Deposits - Schedule of composit

Deposits - Schedule of composition of deposits (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Deposits [Abstract]
Noninterest-bearing demand deposits	$ 2,918,574	$ 3,393,666
Interest-bearing transaction deposits	2,856,192	2,857,818
Saving deposits and money market deposits	2,890,944	2,964,421
Time deposits	1,666,652	855,375
Total deposits	10,332,362	10,071,280
Brokered savings deposits and money market deposits	6,055	1,303
Brokered time deposits	283	275
Aggregate amount of time deposits with a minimum denomination of $100,000	976,513	416,445
Aggregate amount of time deposits with a minimum denomination that meets or exceeds the FDIC insurance limit of $250,000	$ 350,276	$ 120,377

Deposits - Schedule of maturiti

Deposits - Schedule of maturities of time deposits (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Time deposits by schedule of maturities
Remainder of 2023	$ 251,302
2024	1,322,335
2025	52,337
2026	19,438
2027	12,888
2028	7,813
Thereafter	539
Time deposits	$ 1,666,652	$ 855,375

Borrowings - Schedule of distri

Borrowings - Schedule of distribution of securities sold under agreements to repurchase and short-term borrowings and weighted average interest rates (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Securities sold under agreements to repurchase	$ 183,702	$ 229,806
Weighted average rate for securities sold under agreements to repurchase	3.07%	1.91%

Borrowings - Term Loan (Details

Borrowings - Term Loan (Details) - USD ($)	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022	Apr. 30, 2022	May 28, 2021
Short-Term Debt [Line Items]
Long-term debt	$ 21,000,000	$ 30,000,000
Term Loan
Short-Term Debt [Line Items]
Issuance of debt				$ 60,000,000
Long-term debt	21,000,000	$ 30,000,000
Revolving Credit Facility
Short-Term Debt [Line Items]
Issuance of debt				$ 40,000,000
Quarterly payments on the term loan reduce the outstanding principal balance, amount	3,000,000
Second Amended and Restated Credit Agreement | Term Loan
Short-Term Debt [Line Items]
Long-term debt	33,000,000
Long-term debt, current	12,000,000
Long term debt, noncurrent	21,000,000
Second Amended and Restated Credit Agreement | Revolving Credit Facility
Short-Term Debt [Line Items]
Balance outstanding	$ 0
Second Amended and Restated Credit Agreement | One-month LIBOR rate | Term Loan
Short-Term Debt [Line Items]
Interest rate				1.75%
Third Amendment To Extend Credit Facility | SOFR-indexed interest rate | Term Loan
Short-Term Debt [Line Items]
Interest rate			1.80%

Borrowings - Schedule of Short-

Borrowings - Schedule of Short-term Borrowings (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($) note
Short-Term Debt [Line Items]
Total short-term debt	$ 12,000,000	$ 351,054,000
Weighted average rate for securities sold under agreements to repurchase	3.07%	1.91%
Weighted average maturity period for securities sold under agreements to repurchase		5 days
Federal funds purchased	$ 0	$ 0
FHLB advances maturing in less than one year from date of origination, and the current portion of long-term FHLB advances due within 12 months
Short-Term Debt [Line Items]
Total short-term debt	0	339,054,000
Term Loan, current portion due within 12 months
Short-Term Debt [Line Items]
Total short-term debt	$ 12,000,000	$ 12,000,000
Federal Home Loan Bank Certificates and Obligations (FHLB)
Short-Term Debt [Line Items]
Number of notes | note		4
Weighted average rate for securities sold under agreements to repurchase		4.28%
Minimum
Short-Term Debt [Line Items]
Short-term borrowings, mature period	1 day
Maximum
Short-Term Debt [Line Items]
Short-term borrowings, mature period	90 days

Borrowings - Summary of Long-te

Borrowings - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt	$ 21,000	$ 30,000
Term Loan
Debt Instrument [Line Items]
Long-term debt	$ 21,000	$ 30,000

Borrowings - Subordinated Notes

Borrowings - Subordinated Notes (Details) - Subordinated Debt - USD ($) $ in Millions	Jun. 02, 2022	Jun. 01, 2020
5.25% notes maturing June 1, 2030
Debt Instrument [Line Items]
Issuance of debt		$ 125
Floating interest rate margin (as a percent)		5.11%
Duration of fixed interest rate		5 years
5.25% notes maturing June 1, 2030 | Base Rate
Debt Instrument [Line Items]
Interest rate		5.25%
5.000% notes due 2032
Debt Instrument [Line Items]
Issuance of debt	$ 100
Fixed to floating interest rate	5%
Percentage of principal amount of notes	100%
5.000% notes due 2032 | SOFR
Debt Instrument [Line Items]
Floating interest rate margin (as a percent)	2.52%

Borrowings - Schedule of unamor

Borrowings - Schedule of unamortized debt issuance cost (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total unamortized debt issuance costs	$ 2,334	$ 2,962
Subordinated notes issued in 2020 | Subordinated Debt
Debt Instrument [Line Items]
Total unamortized debt issuance costs	859	1,220
Subordinated notes issued in 2022 | Subordinated Debt
Debt Instrument [Line Items]
Total unamortized debt issuance costs	$ 1,475	$ 1,742

Regulatory Capital - Capital Am

Regulatory Capital - Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount
Actual	$ 1,144,403	$ 1,081,686
Minimum Capital Requirement	411,165	406,980
Minimum To Be Well Capitalized	$ 593,905	$ 587,861
Common Equity Tier 1 Capital to Risk Weighted Assets, Ratio
Actual	12.52%	11.96%
Minimum Capital Requirement	4.50%	4.50%
Minimum To Be Well Capitalized	6.50%	6.50%
Tier 1 Capital to Risk Weighted Assets, Amount
Actual	$ 1,218,403	$ 1,155,686
Minimum Capital Requirement	548,220	542,640
Minimum To Be Well Capitalized	$ 730,960	$ 723,521
Tier 1 Capital to Risk Weighted Assets, Ratio
Actual	13.33%	12.78%
Minimum Capital Requirement	6%	6%
Minimum To Be Well Capitalized	8%	8%
Total Capital to Risk Weighted Assets, Amount
Actual	$ 1,527,627	$ 1,457,994
Minimum Capital Requirement	730,960	723,521
Minimum To Be Well Capitalized	$ 913,700	$ 904,401
Total Capital to Risk Weighted Assets, Ratio
Actual	16.72%	16.12%
Minimum Capital Requirement	8%	8%
Minimum To Be Well Capitalized	10%	10%
Leverage Ratio of Tier 1 Capital to Average Assets, Amount
Actual	$ 1,218,403	$ 1,155,686
Minimum Capital Requirement	$ 483,272	$ 489,124
Leverage Ratio of Tier 1 Capital to Average Assets, Ratio
Actual	10.08%	9.45%
Minimum Capital Requirement	4%	4%
Busey Bank
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount
Actual	$ 1,356,565	$ 1,306,716
Minimum Capital Requirement	409,979	405,736
Minimum To Be Well Capitalized	$ 592,192	$ 586,063
Common Equity Tier 1 Capital to Risk Weighted Assets, Ratio
Actual	14.89%	14.49%
Minimum Capital Requirement	4.50%	4.50%
Minimum To Be Well Capitalized	6.50%	6.50%
Tier 1 Capital to Risk Weighted Assets, Amount
Actual	$ 1,356,565	$ 1,306,716
Minimum Capital Requirement	546,639	540,981
Minimum To Be Well Capitalized	$ 728,852	$ 721,308
Tier 1 Capital to Risk Weighted Assets, Ratio
Actual	14.89%	14.49%
Minimum Capital Requirement	6%	6%
Minimum To Be Well Capitalized	8%	8%
Total Capital to Risk Weighted Assets, Amount
Actual	$ 1,440,789	$ 1,384,024
Minimum Capital Requirement	728,852	721,308
Minimum To Be Well Capitalized	$ 911,064	$ 901,635
Total Capital to Risk Weighted Assets, Ratio
Actual	15.81%	15.35%
Minimum Capital Requirement	8%	8%
Minimum To Be Well Capitalized	10%	10%
Leverage Ratio of Tier 1 Capital to Average Assets, Amount
Actual	$ 1,356,565	$ 1,306,716
Minimum Capital Requirement	481,856	487,541
Minimum To Be Well Capitalized	$ 602,321	$ 609,426
Leverage Ratio of Tier 1 Capital to Average Assets, Ratio
Actual	11.26%	10.72%
Minimum Capital Requirement	4%	4%
Minimum To Be Well Capitalized	5%	5%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of changes in the Company's stock option awards (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Shares
Outstanding at beginning of year (in shares)	26,106
Forfeited (in shares)	(4,180)
Outstanding at end of year (in shares)	21,926	26,106
Exercisable at end of year (in shares)	21,926
Weighted- Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$ 23.53
Forfeited (in dollars per share)	23.53
Outstanding at end of year (in dollars per share)	23.53	$ 23.53
Exercisable at end of year (in dollars per share)	$ 23.53
Weighted- Average Remaining Contractual Life
Weighted-average remaining contractual life, options outstanding	3 years 1 month 17 days	3 years 10 months 17 days
Weighted-average remaining contractual life, exercisable at end of year	3 years 1 month 17 days

Stock-Based Compensation - Amen

Stock-Based Compensation - Amended 2020 Equity Plan (Details) - shares	Apr. 14, 2023	Sep. 30, 2023
2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Remaining shares available for issuance (in shares)		1,525,987
Amended 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Increase in the number of shares authorized for issuance (in shares)	1,350,000

Stock-Based Compensation - RSU,

Stock-Based Compensation - RSU, PSU, and DSU Narrative (Details) - USD ($) $ in Millions		9 Months Ended	12 Months Ended
	Mar. 22, 2023	Sep. 30, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Period over which cost will be recognized		2 years 6 months	2 years 6 months
RSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares of common stock per award (in shares)		1
Granted (in shares)		224,316
RSU Awards | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Requisite service periods		1 year
RSU Awards | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Requisite service periods		5 years
PSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares of common stock per award (in shares)		1
Granted (in shares)		224,331
PSU Awards | 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	15,045
Grant date fair value of the award	$ 0.3
PSU Awards | 2020 Equity Plan | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage	0%
PSU Awards | 2020 Equity Plan | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	30,090
Vesting percentage	200%
DSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares of common stock per award (in shares)		1
Granted (in shares)		41,548
Vesting period		1 year
Settlement period		30 days
Market Based Performance Stock Units | 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	104,643
Grant date fair value of the award	$ 2
Market Based Performance Stock Units | 2020 Equity Plan | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage	0%
Market Based Performance Stock Units | 2020 Equity Plan | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	167,429
Vesting percentage	160%
Performance Based Performance Stock Units | 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	104,643
Grant date fair value of the award	$ 2.1
Performance Based Performance Stock Units | 2020 Equity Plan | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting percentage	0%
Performance Based Performance Stock Units | 2020 Equity Plan | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	167,429
Vesting percentage	160%
Members of management, including the Vice-Chairman of the Board | RSU Awards | 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	224,316
Grant date fair value of the award	$ 4.6
Vesting percentage	100%
Members of management, including the Vice-Chairman of the Board | RSU Awards | 2020 Equity Plan | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Period over which cost will be recognized	1 year
Members of management, including the Vice-Chairman of the Board | RSU Awards | 2020 Equity Plan | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Period over which cost will be recognized	5 years
Directors and Advisory Directors | DSU Awards | 2020 Equity Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)	41,548
Grant date fair value of the award	$ 0.8
Period over which cost will be recognized	1 year
Vesting percentage	100%

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of changes in the Company's RSU, PSU, and DSU awards (Details)	9 Months Ended
	Sep. 30, 2023 $ / shares shares
RSU Awards
Shares
Non-vested at beginning of period (in shares) | shares	1,096,931
Granted (in shares) | shares	224,316
Dividend equivalents earned (in shares) | shares	43,841
Vested (in shares) | shares	(150,806)
Forfeited (in shares) | shares	(14,145)
Non-vested at end of period (in shares) | shares	1,200,137
Weighted- Average Grant Date Fair Value
Non-vested at beginning of period (in dollars per share) | $ / shares	$ 23.61
Granted (in dollars per share) | $ / shares	20.44
Dividend equivalents earned (in dollars per share) | $ / shares	20.53
Vested (in dollars per share) | $ / shares	29.91
Forfeited (in dollars per share) | $ / shares	22
Non-vested at end of period (in dollars per share) | $ / shares	$ 22.13
PSU Awards
Shares
Non-vested at beginning of period (in shares) | shares	285,351
Granted (in shares) | shares	224,331
Dividend equivalents earned (in shares) | shares	92
Vested (in shares) | shares	(13,155)
Forfeited (in shares) | shares	(40,159)
Non-vested at end of period (in shares) | shares	456,460
Vested and outstanding at end of period (in shares) | shares	13,063
Weighted- Average Grant Date Fair Value
Non-vested at beginning of period (in dollars per share) | $ / shares	$ 25.40
Granted (in dollars per share) | $ / shares	20.04
Dividend equivalents earned (in dollars per share) | $ / shares	22.85
Vested (in dollars per share) | $ / shares	25.50
Forfeited (in dollars per share) | $ / shares	24.98
Non-vested at end of period (in dollars per share) | $ / shares	22.80
Vested and outstanding at end of period (in dollars per share) | $ / shares	$ 25.52
DSU Awards
Shares
Non-vested at beginning of period (in shares) | shares	31,085
Granted (in shares) | shares	41,548
Dividend equivalents earned (in shares) | shares	6,010
Vested (in shares) | shares	(36,078)
Forfeited (in shares) | shares	(73)
Non-vested at end of period (in shares) | shares	42,492
Vested and outstanding at end of period (in shares) | shares	142,347
Weighted- Average Grant Date Fair Value
Non-vested at beginning of period (in dollars per share) | $ / shares	$ 25.75
Granted (in dollars per share) | $ / shares	20.44
Dividend equivalents earned (in dollars per share) | $ / shares	20.48
Vested (in dollars per share) | $ / shares	25.04
Forfeited (in dollars per share) | $ / shares	20.44
Non-vested at end of period (in dollars per share) | $ / shares	20.42
Vested and outstanding at end of period (in dollars per share) | $ / shares	$ 23.58

Stock-Based Compensation - 2021

Stock-Based Compensation - 2021 Employee Stock Purchase Plan (Details) - USD ($)		3 Months Ended		9 Months Ended
	Jul. 01, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock option compensation expense		$ 2,603,000	$ 2,476,000	$ 6,928,000	$ 6,721,000
Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock option compensation expense		$ 0	$ 0	0	$ 0
Unrecognized stock option compensation expense				$ 0
2021 ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Discount through voluntary payroll deductions	15%
Remaining shares available for issuance (in shares)	600,000	460,340		460,340

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	$ 2,603	$ 2,476	$ 6,928	$ 6,721
RSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	1,177	1,072	3,428	3,521
PSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	1,180	1,172	2,724	2,342
DSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	213	196	620	679
2021 ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	$ 33	$ 36	$ 156	$ 179

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Unamortized stock-based compensation expense (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total unamortized stock-based compensation	$ 15,782	$ 13,024
Weighted average period over which expense is to be recognized	2 years 6 months	2 years 6 months
RSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total unamortized stock-based compensation	$ 9,437	$ 8,570
PSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total unamortized stock-based compensation	5,942	4,279
DSU Awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total unamortized stock-based compensation	$ 403	$ 175

Outstanding Commitments and C_3

Outstanding Commitments and Contingent Liabilities - Schedule of contractual amount of exposure to off-balance-sheet risk (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Credit Commitments and Contingencies
Total commitments	$ 2,167,785	$ 2,024,777
Commitments to extend credit
Credit Commitments and Contingencies
Total commitments	2,130,938	1,991,769
Standby letters of credit
Credit Commitments and Contingencies
Total commitments	$ 36,847	$ 33,008

Derivative Financial Instrume_3

Derivative Financial Instruments - Schedule of financial instruments owned and pledged as collateral (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Interest Rate Swap
Derivative [Line Items]
Cash pledged to secure obligations	$ 34,210	$ 38,609
Interest Rate Contract
Derivative [Line Items]
Cash pledged to secure obligations	$ 34,620	$ 29,830

Derivative Financial Instrume_4

Derivative Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Interest Rate Swap | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 300,000
Interest Rate Swap | Not Designated as Hedging Instrument
Derivative [Line Items]
Variable rate, commercial loans that are supported by the interest rate swap contracts	628,300	$ 576,900
Interest Rate Swap | Cash Flow Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	350,000	350,000
Debt Swap | Cash Flow Hedging
Derivative [Line Items]
Notional amount	50,000	$ 50,000
Debt Swap | Cash Flow Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 50,000

Derivative Financial Instrume_5

Derivative Financial Instruments - Summary of the interest-rate swaps designated as cash flow hedges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Interest Rate Swap
Balances carried in AOCI
Unrealized gains (losses) on cash flow hedges, net of tax	$ 0	$ 0	$ 0	$ 0
Cash Flow Hedging | Interest Rate Swap
Balances carried in AOCI
Unrealized gains (losses) on cash flow hedges, net of tax			(25,092)		$ (20,985)
Cash Flow Hedging | Interest Rate Swap | Other assets
Gross aggregate fair value of the swaps
Gross aggregate fair value of swap assets	1,886		1,886		2,535
Cash Flow Hedging | Interest Rate Swap | Other liabilities
Gross aggregate fair value of the swaps
Gross aggregate fair value of swap liabilities	37,725		37,725		32,367
Cash Flow Hedging | Debt Swap
Derivative [Line Items]
Notional amount	$ 50,000		$ 50,000		$ 50,000
Weighted average fixed pay/receive rates	1.79%		1.79%		1.79%
Weighted average variable interest rates	5.55%		5.55%		4.77%
Weighted average maturity			11 months 15 days		1 year 8 months 15 days
Cash Flow Hedging | Loan Swap
Derivative [Line Items]
Notional amount	$ 300,000		$ 300,000		$ 300,000
Weighted average fixed pay/receive rates	4.81%		4.81%		4.81%
Weighted average variable interest rates	8.50%		8.50%		7.32%
Weighted average maturity			5 years 4 months 6 days		6 years 1 month 6 days

Derivative Financial Instrume_6

Derivative Financial Instruments - Reclassification of unrealized gains and losses from OCI (Details) - Interest Rate Swap - Cash Flow Hedging $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)
Derivative [Line Items]
Net unrealized gains (losses) in OCI expected to be recognized in net interest income	$ (441)
Interest Income
Derivative [Line Items]
Net unrealized gains (losses) in OCI expected to be recognized in net interest income	(922)
Interest Expense
Derivative [Line Items]
Net unrealized gains (losses) in OCI expected to be recognized in net interest income	$ 481

Derivative Financial Instrume_7

Derivative Financial Instruments - Schedule of interest income (expense) recorded on swap transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
(Increase) decrease in interest expense on swap transactions	$ (44,878)	$ (9,110)	$ (108,355)	$ (21,813)
Interest Rate Swap | Cash Flow Hedging
Derivative [Line Items]
Increase (decrease) in interest income on swap transactions	(2,771)	(405)	(7,500)	947
(Increase) decrease in interest expense on swap transactions	481	35	1,268	(250)
Net increase (decrease) in net interest income on swap transactions	$ (2,290)	$ (370)	$ (6,232)	$ 697

Derivative Financial Instrume_8

Derivative Financial Instruments - Net Gains (Losses) Recorded in Accumulated Other Comprehensive Income (Loss) (Details) - Cash Flow Hedging - Interest Rate Contract - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Net gain (loss) recognized in OCI, net of tax	$ (5,577)	$ (10,192)	$ (8,563)	$ (21,587)
(Gain) loss reclassified from OCI to interest income, net of tax	1,982	(24)	5,362	(992)
(Gain) loss reclassified from OCI to interest expense, net of tax	(344)	290	(906)	494
Net change in unrealized gains (losses) on cash flow hedges, net of tax	$ (3,939)	$ (9,926)	$ (4,107)	$ (22,085)

Derivative Financial Instrume_9

Derivative Financial Instruments - Interest Rate Swaps Not Designated as Hedges (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Interest Rate Swap
Derivative Asset
Notional Amount	$ 628,291	$ 576,911
Fair Value	45,013	40,055
Derivative Liability
Notional Amount	628,291	576,911
Fair Value	45,013	40,055
Interest rate swaps – pay floating, receive fixed
Derivative Asset
Notional Amount	9,320	48,728
Fair Value	99	370
Derivative Liability
Notional Amount	618,971	528,183
Fair Value	44,914	39,685
Interest rate swaps – pay fixed, receive floating
Derivative Asset
Notional Amount	618,971	528,183
Fair Value	44,914	39,685
Derivative Liability
Notional Amount	9,320	48,728
Fair Value	$ 99	$ 370

Derivative Financial Instrum_10

Derivative Financial Instruments - Interest Rate Swaps Recorded in Noninterest Expense (Details) - Interest Rate Swap - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Net change in fair value of interest rate swaps	$ 0	$ 0	$ 0	$ 0
Noninterest expense
Derivative [Line Items]
Gain (loss), pay floating, receive fixed	9,007	18,317	4,646	21,792
Gain (loss), pay fixed, receive floating	$ (9,007)	$ (18,317)	$ (4,646)	$ (21,792)

Derivative Financial Instrum_11

Derivative Financial Instruments - Risk Participation Agreement (Details) $ in Thousands	Sep. 30, 2023 USD ($) agreement	Dec. 31, 2022 USD ($) agreement
Risk participation agreements purchased
Derivative [Line Items]
Number of risk participation agreements | agreement	3	2
Notional amount	$ 34,274	$ 18,899
Fair value	$ 7	$ 5
Risk participation agreements sold
Derivative [Line Items]
Number of risk participation agreements | agreement	1	0
Notional amount	$ 20,001	$ 0
Fair value	$ 0	$ 0

Derivative Financial Instrum_12

Derivative Financial Instruments - Foreign Currency Forward Contracts (Details) - Foreign currency forward contracts - Not Designated as Hedging Instrument $ in Thousands	Sep. 30, 2023 USD ($)
Derivative Asset
Notional Amount	$ 354
Fair Value	58
Derivative Liability
Notional Amount	344
Fair Value	(48)
Buy
Derivative Asset
Notional Amount	354
Fair Value	58
Derivative Liability
Notional Amount	0
Fair Value	0
Sell
Derivative Asset
Notional Amount	0
Fair Value	0
Derivative Liability
Notional Amount	344
Fair Value	$ (48)

Derivative Financial Instrum_13

Derivative Financial Instruments - Mortgage Banking Derivatives (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Derivatives with positive fair value
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Derivatives with negative fair value
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities
Interest rate lock commitments
Derivatives with positive fair value
Notional Amount	$ 715	$ 1,517
Fair value recorded in other assets	4	16
Derivatives with negative fair value
Notional Amount	1,366	83
Fair value recorded in other liabilities	16	1
Forward sales commitments
Derivatives with positive fair value
Notional Amount	3,249	83
Fair value recorded in other assets	66	1
Derivatives with negative fair value
Notional Amount	1,795	2,757
Fair value recorded in other liabilities	12	39
Mortgage banking derivatives recorded in other assets | Designated as Hedging Instrument
Derivatives with positive fair value
Notional Amount	3,964	1,600
Fair value recorded in other assets	70	17
Derivatives with negative fair value
Notional Amount	3,161	2,840
Fair value recorded in other liabilities	$ 28	$ 40

Derivative Financial Instrum_14

Derivative Financial Instruments - Net Gains (Losses) Relating to Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Mortgage revenue			Mortgage revenue
Interest rate lock commitments | Designated as Hedging Instrument
Derivative [Line Items]
Net change in fair value of interest rate swaps	$ (16)	$ (111)	$ (28)	$ 38
Forward sales commitments | Designated as Hedging Instrument
Derivative [Line Items]
Net change in fair value of interest rate swaps	60	295	92	82
Net gains (losses) | Designated as Hedging Instrument
Derivative [Line Items]
Net change in fair value of interest rate swaps	$ 44	$ 184	$ 64	$ 120

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of financial assets and financial liabilities measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	$ 2,182,841	$ 2,461,393
Equity securities	8,782	11,535
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	50,130	114,061
Obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	9,819	19,779
Obligations of states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	226,797	257,512
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	479,448	469,875
Commercial mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	100,300	108,394
Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	1,088,796	1,243,256
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	227,551	248,516
Fair Value, Recurring | Derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	47,034	42,612
Fair Value, Recurring | Derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	82,814	72,462
Fair Value, Recurring | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	50,130	114,061
Fair Value, Recurring | Obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	9,819	19,779
Fair Value, Recurring | Obligations of states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	226,797	257,512
Fair Value, Recurring | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	479,448	469,875
Fair Value, Recurring | Commercial mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	100,300	108,394
Fair Value, Recurring | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	1,088,796	1,243,256
Fair Value, Recurring | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	227,551	248,516
Fair Value, Recurring | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	8,782	11,535
Fair Value, Recurring | Level 1 Inputs | Derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Fair Value, Recurring | Level 1 Inputs | Derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Fair Value, Recurring | Level 1 Inputs | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Obligations of states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Commercial mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 1 Inputs | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Fair Value, Recurring | Level 2 Inputs | Derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	47,027	42,607
Fair Value, Recurring | Level 2 Inputs | Derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	82,814	72,462
Fair Value, Recurring | Level 2 Inputs | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	50,130	114,061
Fair Value, Recurring | Level 2 Inputs | Obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	9,819	19,779
Fair Value, Recurring | Level 2 Inputs | Obligations of states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	226,797	257,512
Fair Value, Recurring | Level 2 Inputs | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	479,448	469,875
Fair Value, Recurring | Level 2 Inputs | Commercial mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	100,300	108,394
Fair Value, Recurring | Level 2 Inputs | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	1,088,796	1,243,256
Fair Value, Recurring | Level 2 Inputs | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	227,551	248,516
Fair Value, Recurring | Level 2 Inputs | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	8,782	11,535
Fair Value, Recurring | Level 3 Inputs | Derivative assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	7	5
Fair Value, Recurring | Level 3 Inputs | Derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Fair Value, Recurring | Level 3 Inputs | U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Obligations of U.S. government corporations and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Obligations of states and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Commercial mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	0	0
Fair Value, Recurring | Level 3 Inputs | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 0	$ 0

Fair Value Measurements - Sch_2

Fair Value Measurements - Schedule of assets and liabilities measured at fair value on a non-recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans evaluated individually, net of related allowance	$ 6,997	$ 15,647
Loans evaluated individually, net of related allowance | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans evaluated individually, net of related allowance	3,333	5,345
Loans evaluated individually, net of related allowance | Level 1 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans evaluated individually, net of related allowance	0	0
Loans evaluated individually, net of related allowance | Level 2 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans evaluated individually, net of related allowance	0	0
Loans evaluated individually, net of related allowance | Level 3 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans evaluated individually, net of related allowance	3,333	5,345
Bank property held for sale with impairment | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Bank property held for sale with impairment	4,286	7,923
Bank property held for sale with impairment | Level 1 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Bank property held for sale with impairment	0	0
Bank property held for sale with impairment | Level 2 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Bank property held for sale with impairment	0	0
Bank property held for sale with impairment | Level 3 Inputs | Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Bank property held for sale with impairment	$ 4,286	$ 7,923

Fair Value Measurements - Sch_3

Fair Value Measurements - Schedule of quantitative information about Level 3 fair value measurements (Details) $ in Thousands	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value
Loans evaluated individually, net of related allowance	$ 6,997	$ 15,647
Fair Value, Nonrecurring | Loans evaluated individually, net of related allowance
Fair Value
Loans evaluated individually, net of related allowance	3,333	5,345
Fair Value, Nonrecurring | Bank property held for sale with impairment
Fair Value
Bank property held for sale with impairment	4,286	7,923
Fair Value, Nonrecurring | Level 3 Inputs | Loans evaluated individually, net of related allowance
Fair Value
Loans evaluated individually, net of related allowance	3,333	5,345
Fair Value, Nonrecurring | Level 3 Inputs | Bank property held for sale with impairment
Fair Value
Bank property held for sale with impairment	4,286	7,923
Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral | Loans evaluated individually, net of related allowance
Fair Value
Loans evaluated individually, net of related allowance	3,333	5,345
Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral or real estate listing price | Bank property held for sale with impairment
Fair Value
Bank property held for sale with impairment	$ 4,286	$ 7,923
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral | Loans evaluated individually, net of related allowance | Minimum
Range (Weighted Average)
Loans evaluated individually, net of related allowance	(0.105)	(0.227)
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral | Loans evaluated individually, net of related allowance | Maximum
Range (Weighted Average)
Loans evaluated individually, net of related allowance	(1)	(1)
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral | Loans evaluated individually, net of related allowance | Weighted Average
Range (Weighted Average)
Loans evaluated individually, net of related allowance	(0.340)	(0.457)
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral or real estate listing price | Bank property held for sale with impairment | Minimum
Range (Weighted Average)
Bank property held for sale with impairment	(0.062)	(0.007)
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral or real estate listing price | Bank property held for sale with impairment | Maximum
Range (Weighted Average)
Bank property held for sale with impairment	(0.649)	(0.701)
Measurement Input, Comparability Adjustment | Fair Value, Nonrecurring | Level 3 Inputs | Appraisal of collateral or real estate listing price | Bank property held for sale with impairment | Weighted Average
Range (Weighted Average)
Bank property held for sale with impairment	(0.384)	(0.351)

Fair Value Measurements - Sch_4

Fair Value Measurements - Schedule of estimated fair values of financial instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial assets
Debt securities held to maturity	$ 701,676	$ 785,295
Portfolio loans, net	7,764,450	7,634,094
Financial liabilities
Short-term borrowings	12,000	351,054
Junior subordinated debt owed to unconsolidated trusts	71,946	71,810
Level 1 Inputs | Carrying Amount
Financial assets
Cash and cash equivalents	337,919	227,164
Level 1 Inputs | Fair Value
Financial assets
Cash and cash equivalents	337,919	227,164
Level 2 Inputs | Carrying Amount
Financial assets
Debt securities held to maturity	882,614	918,312
Loans held for sale	3,051	1,253
Accrued interest receivable	47,889	43,372
Financial liabilities
Time deposits	1,666,652	855,375
Securities sold under agreements to repurchase	183,702	229,806
Short-term borrowings	12,000	351,054
Long-term debt	21,000	30,000
Junior subordinated debt owed to unconsolidated trusts	71,946	71,810
Accrued interest payable	22,761	3,978
Level 2 Inputs | Fair Value
Financial assets
Debt securities held to maturity	701,676	785,295
Loans held for sale	3,059	1,276
Accrued interest receivable	47,889	43,372
Financial liabilities
Time deposits	1,643,625	830,596
Securities sold under agreements to repurchase	183,702	229,806
Short-term borrowings	12,027	351,085
Long-term debt	21,020	30,052
Junior subordinated debt owed to unconsolidated trusts	55,662	59,111
Accrued interest payable	22,761	3,978
Level 3 Inputs | Carrying Amount
Financial assets
Portfolio loans, net	7,764,450	7,634,094
Mortgage servicing rights	3,870	5,861
Other servicing rights	1,675	1,914
Level 3 Inputs | Fair Value
Financial assets
Portfolio loans, net	7,241,479	7,320,422
Mortgage servicing rights	18,758	18,284
Other servicing rights	2,144	2,331
Level 3 Inputs | Subordinated Debt | Carrying Amount
Financial liabilities
Long-term debt	222,666	222,038
Level 3 Inputs | Subordinated Debt | Fair Value
Financial liabilities
Long-term debt	$ 198,812	$ 208,562

Earnings Per Common Share - Sch

Earnings Per Common Share - Schedule of computation of earnings per common share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net income per share calculations for basic and diluted methods
Net income	$ 30,666	$ 35,661	$ 96,816	$ 93,924
Weighted Average Shares Outstanding
Weighted average number of common shares outstanding, basic (in shares)	55,486,700	55,349,547	55,441,980	55,399,424
Weighted average number of common shares outstanding, diluted (in shares)	56,315,492	56,073,164	56,230,624	56,123,756
Basic earnings per common share (in dollars per share)	$ 0.55	$ 0.64	$ 1.75	$ 1.70
Diluted earnings per common share (in dollars per share)	$ 0.54	$ 0.64	$ 1.72	$ 1.67
Options
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	0	249	0	1,606
Warrants
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	0	1,708	432	1,749
RSU Awards
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	640,714	624,576	638,495	661,173
PSU Awards
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	165,868	81,268	126,787	37,393
DSU Awards
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	16,792	10,414	14,996	14,275
ESPP
Weighted Average Shares Outstanding
Dilutive effect of common stock equivalents (in shares)	5,418	5,402	7,934	8,136

Earnings Per Common Share - S_2

Earnings Per Common Share - Schedule of average shares excluded from computation of diluted earnings per common share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	107,000	160,391	212,731	289,043
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	21,926	0	22,219	10,389
RSU Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	0	0	52,594	51,883
PSU Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive common stock equivalents (in shares)	85,074	160,391	137,918	226,771

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, net of tax	$ 1,201,948	$ 1,161,957	$ 1,145,977	$ 1,319,112
Unrealized/Unrecognized gains (losses) on debt securities
Unrealized holding gains (losses) on debt securities available for sale, net of tax	(26,950)	(69,306)	(16,872)	(211,988)
Unrealized losses on debt securities transferred to held to maturity from available for sale, net of tax	0	0	0	(34,644)
Amounts reclassified from AOCI, net of tax	(24)	(53)	(148)	20
Amortization of unrealized losses on securities transferred to held to maturity, net of tax	(1,056)	(1,291)	(3,379)	(3,500)
Unrealized gains (losses) on cash flow hedges
Unrealized holding gains (losses) on cash flow hedges, net of tax	(5,577)	(10,192)	(8,563)	(21,587)
Amounts reclassified from AOCI, net of tax	(1,638)	(266)	(4,456)	498
Ending balance, net of tax	1,190,158	1,106,588	1,190,158	1,106,588
AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, net of tax	(260,921)	(211,107)	(273,278)	(23,758)
Unrealized gains (losses) on cash flow hedges
Accumulated other comprehensive income (loss) ending balance period, before tax	(406,639)	(404,213)	(406,639)	(404,213)
Accumulated other comprehensive income (loss) ending balance period, tax effect	115,909	115,218	115,909	115,218
Ending balance, net of tax	(290,730)	(288,995)	(290,730)	(288,995)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss) beginning balance period, before tax	(335,359)	(277,310)	(352,878)	(32,272)
Accumulated other comprehensive income (loss) beginning balance period, tax effect	95,591	79,047	100,585	9,199
Beginning balance, net of tax	(239,768)	(198,263)	(252,293)	(23,073)
Unrealized/Unrecognized gains (losses) on debt securities
Unrealized holding gains (losses) on debt securities available for sale, before tax	(37,696)	(96,937)	(23,600)	(296,507)
Unrealized holding gains (losses) on debt securities available for sale, tax effect	10,746	27,631	6,728	84,519
Unrealized holding gains (losses) on debt securities available for sale, net of tax	(26,950)	(69,306)	(16,872)	(211,988)
Unrealized losses on debt securities transferred to held to maturity from available for sale, before tax			0	(48,456)
Unrealized losses on debt securities transferred to held to maturity from available for sale, tax effect	0	0	0	13,812
Unrealized losses on debt securities transferred to held to maturity from available for sale, net of tax			0	(34,644)
Amounts reclassified from AOCI, before tax	33	74	207	(28)
Reclassification adjustment for realized (gains) losses on debt securities available for sale included in net income, tax expense (benefit)	(9)	(21)	(59)	8
Amounts reclassified from AOCI, net of tax	24	53	148	(20)
Amortization of unrealized losses on securities transferred to held to maturity, before tax	1,476	1,806	4,725	4,896
Amortization of unrealized losses on securities transferred to held to maturity, tax effect	420	515	1,346	1,396
Amortization of unrealized losses on securities transferred to held to maturity, net of tax	1,056	1,291	3,379	3,500
Unrealized gains (losses) on cash flow hedges
Accumulated other comprehensive income (loss) ending balance period, before tax	(371,546)	(372,367)	(371,546)	(372,367)
Accumulated other comprehensive income (loss) ending balance period, tax effect	105,908	106,142	105,908	106,142
Ending balance, net of tax	(265,638)	(266,225)	(265,638)	(266,225)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss) beginning balance period, before tax	(29,586)	(17,963)	(29,350)	(958)
Accumulated other comprehensive income (loss) beginning balance period, tax effect	8,433	5,119	8,365	273
Beginning balance, net of tax	(21,153)	(12,844)	(20,985)	(685)
Unrealized gains (losses) on cash flow hedges
Unrealized holding gains (losses) on cash flow hedges, before tax	(7,797)	(14,253)	(11,975)	(30,191)
Unrealized holding gains (losses) on cash flow hedges, tax effect	2,220	4,061	3,412	8,604
Unrealized holding gains (losses) on cash flow hedges, net of tax	(5,577)	(10,192)	(8,563)	(21,587)
(Gain) loss reclassified from OCI to interest expense, net of tax	2,290	370	6,232	(697)
Amounts reclassified from AOCI, tax effect	(652)	(104)	(1,776)	199
Amounts reclassified from AOCI, net of tax	1,638	266	4,456	(498)
Accumulated other comprehensive income (loss) ending balance period, before tax	(35,093)	(31,846)	(35,093)	(31,846)
Accumulated other comprehensive income (loss) ending balance period, tax effect	10,001	9,076	10,001	9,076
Ending balance, net of tax	$ (25,092)	$ (22,770)	$ (25,092)	$ (22,770)

Operating Segments and Relate_3

Operating Segments and Related Information - Narrative (Details)	9 Months Ended
	Sep. 30, 2023 segment center
Segment Reporting [Abstract]
Number of reportable segments	3
Number of operating segments	3
Number of banking centers consolidated | center	58

Operating Segments and Relate_4

Operating Segments and Related Information - Summary of information relating to operating segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Segment Reporting Information [Line Items]
Goodwill	$ 317,873		$ 317,873		$ 317,873
Total Assets	12,258,250		12,258,250		12,336,677
Net interest income	77,791	$ 86,305	242,318	$ 232,289
Noninterest income	31,008	30,933	90,868	97,724
Noninterest expense	70,945	70,736	210,553	210,204
Income before income taxes	37,490	44,138	120,689	116,045
Net income	30,666	35,661	96,816	93,924
Operating segment | Banking
Segment Reporting Information [Line Items]
Goodwill	294,773		294,773		294,773
Total Assets	12,104,706		12,104,706		12,199,960
Net interest income	81,794	90,916	254,394	244,820
Noninterest income	11,983	13,559	34,716	42,827
Noninterest expense	55,172	55,273	163,314	165,220
Income before income taxes	38,241	46,838	123,852	118,663
Net income	31,189	37,082	98,689	94,032
Operating segment | Wealth Management
Segment Reporting Information [Line Items]
Goodwill	14,108		14,108		14,108
Total Assets	98,755		98,755		84,082
Noninterest income	14,350	12,514	43,993	42,425
Noninterest expense	8,059	7,682	24,821	23,533
Income before income taxes	6,291	4,832	19,172	18,892
Net income	4,781	3,756	14,571	14,688
Operating segment | FirsTech
Segment Reporting Information [Line Items]
Goodwill	8,992		8,992		8,992
Total Assets	50,689		50,689		48,715
Net interest income	14	15	41	50
Noninterest income	5,665	5,578	16,954	16,333
Noninterest expense	5,245	5,109	16,303	14,601
Income before income taxes	434	484	692	1,782
Net income	317	353	505	1,300
Intersegment Eliminations
Segment Reporting Information [Line Items]
Goodwill	0		0		0
Total Assets	4,100		4,100		$ 3,920
Net interest income	(4,017)	(4,626)	(12,117)	(12,581)
Noninterest income	(990)	(718)	(4,795)	(3,861)
Noninterest expense	2,469	2,672	6,115	6,850
Income before income taxes	(7,476)	(8,016)	(23,027)	(23,292)
Net income	$ (5,621)	$ (5,530)	$ (16,949)	$ (16,096)