Trustmark (TRMK) 10-Q 7 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 30, 2024
Cover [Abstract]
Entity Registrant Name	Trustmark Corp
Entity Central Index Key	0000036146
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		61,201,825
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Trading Symbol	TRMK
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Title of 12(b) Security	Common Stock, no par value
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity File Number	000-03683
Entity Incorporation, State or Country Code	MS
Entity Tax Identification Number	64-0471500
Entity Address, Address Line One	248 East Capitol Street
Entity Address, City or Town	Jackson
Entity Address, State or Province	MS
Entity Address, Postal Zip Code	39201
City Area Code	601
Local Phone Number	208-5111
Document Quarterly Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Assets
Cash and due from banks	$ 606,261	$ 975,543
Securities available for sale, at fair value (amortized cost: $1,900,980 - 2024 $1,959,007-2023; allowance for credit losses (ACL): $0)	1,702,299	1,762,878
Securities held to maturity, net of ACL of $0 (fair value: $1,333,014 - 2024; $1,355,504-2023)	1,415,025	1,426,279
Loans held for sale (LHFS)	172,937	184,812
Loans held for investment (LHFI)	13,057,943	12,950,524
Less ACL, LHFI	142,998	139,367
Net LHFI	12,914,945	12,811,157
Premises and equipment, net	232,924	232,537
Mortgage servicing rights (MSR)	138,044	131,870
Goodwill	384,237	384,237
Identifiable intangible assets, net	2,845	2,965
Other real estate, net	7,620	6,867
Operating lease right-of-use assets	36,659	38,142
Other assets	762,816	764,902
Total Assets	18,376,612	18,722,189
Deposits:
Noninterest-bearing	3,039,652	3,197,620
Interest-bearing	12,298,905	12,372,143
Total deposits	15,338,557	15,569,763
Federal funds purchased and securities sold under repurchase agreements	393,215	405,745
Other borrowings	482,027	483,230
Subordinated notes	123,537	123,482
Junior subordinated debt securities	61,856	61,856
ACL on off-balance sheet credit exposures	33,865	34,057
Operating lease liabilities	40,185	41,584
Other liabilities	220,771	340,625
Total Liabilities	16,694,013	17,060,342
Shareholders' Equity
Authorized: 250,000,000 Issued and outstanding: 61,178,366 shares - 2024; 61,071,173 shares - 2023	12,747	12,725
Capital surplus	160,521	159,688
Retained earnings	1,736,485	1,709,157
Accumulated other comprehensive income (loss), net of tax	(227,154)	(219,723)
Total Shareholders' Equity	1,682,599	1,661,847
Total Liabilities and Shareholders' Equity	$ 18,376,612	$ 18,722,189

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Assets
Securities available-for-sale, amortized cost	$ 1,900,980,000	$ 1,959,007,000
Securities available-for-sale, allowance for credit Losses (ACL)	0	0
Securities held to maturity, net of ACL	0	0
Securities held to maturity, fair value	$ 1,333,014,000	$ 1,355,504,000
Shareholders' Equity
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	250,000,000	250,000,000
Common stock, issued (in shares)	61,178,366	61,071,173
Common stock, outstanding (in shares)	61,178,366	61,071,173

Consolidated Statements of Inco

Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest Income
Interest and fees on LHFS & LHFI	$ 206,092	$ 175,509
Interest on securities:
Taxable	15,634	16,761
Tax exempt	3	73
Interest on federal funds sold and securities purchased under reverse repurchase agreements	1	30
Other interest income	8,110	6,527
Total Interest Income	229,840	198,900
Interest Expense
Interest on deposits	83,716	40,898
Interest on federal funds purchased and securities sold under repurchase agreements	5,591	4,832
Other interest expense	7,703	15,575
Total Interest Expense	97,010	61,305
Net Interest Income	132,830	137,595
Provision for credit losses (PCL), LHFI	7,708	3,244
PCL, off-balance sheet credit exposures	(192)	(2,242)
Net Interest Income After PCL	125,314	136,593
Noninterest Income
Service charges on deposit accounts	10,958	10,336
Bank card and other fees	7,428	7,803
Mortgage banking, net	8,915	7,639
Insurance commissions	15,464	14,305
Wealth management	8,952	8,780
Other, net	3,632	2,514
Total Noninterest Income	55,349	51,377
Noninterest Expense
Salaries and employee benefits	75,458	74,056
Services and fees	24,839	25,426
Net occupancy - premises	7,496	7,629
Equipment expense	6,385	6,405
Other expense	16,968	14,811
Total Noninterest Expense	131,146	128,327
Income Before Income Taxes	49,517	59,643
Income taxes	7,982	9,343
Net Income	$ 41,535	$ 50,300
Earnings Per Share
Basic	$ 0.68	$ 0.82
Diluted	$ 0.68	$ 0.82

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 41,535	$ 50,300
Net unrealized gains (losses) on available for sale securities and transferred securities:
Net unrealized holding gains (losses) arising during the period	(1,914)	23,130
Change in net unrealized holding loss on securities transferred to held to maturity	2,746	2,894
Reclassification adjustments for changes realized in net income:
Net change in prior service costs	21	21
Recognized net loss due to lump sum settlement	0	19
Change in net actuarial loss	71	58
Derivatives:
Change in the accumulated gain (loss) on effective cash flow hedge derivatives	(11,970)	4,702
Reclassification adjustment for (gain) loss realized in net income	3,615	2,198
Other comprehensive income (loss), net of tax	(7,431)	33,022
Comprehensive income (loss)	$ 34,104	$ 83,322

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2022	$ 1,492,268	$ 12,705	$ 154,645	$ 1,600,321	$ (275,403)
Balance (in shares) at Dec. 31, 2022		60,977,686
Net Income (Loss)	50,300			50,300
Other comprehensive income (loss), net of tax	33,022				33,022
Common stock dividends paid ($0.23 per share)	(14,158)			(14,158)
Shares withheld to pay taxes, long-term incentive plan	(1,048)	$ 15	(1,063)
Shares withheld to pay taxes, long-term incentive plan (in shares)		70,830
Compensation expense, long-term incentive plan	1,715		1,715
Balance at Mar. 31, 2023	1,562,099	$ 12,720	155,297	1,636,463	(242,381)
Balance (in shares) at Mar. 31, 2023		61,048,516
Balance at Dec. 31, 2023	$ 1,661,847	$ 12,725	159,688	1,709,157	(219,723)
Balance (in shares) at Dec. 31, 2023	61,071,173	61,071,173
Net Income (Loss)	$ 41,535			41,535
Other comprehensive income (loss), net of tax	(7,431)				(7,431)
Common stock dividends paid ($0.23 per share)	(14,207)			(14,207)
Shares withheld to pay taxes, long-term incentive plan	(1,383)	$ 22	(1,405)
Shares withheld to pay taxes, long-term incentive plan (in shares)		107,193
Compensation expense, long-term incentive plan	2,238		2,238
Balance at Mar. 31, 2024	$ 1,682,599	$ 12,747	$ 160,521	$ 1,736,485	$ (227,154)
Balance (in shares) at Mar. 31, 2024	61,178,366	61,178,366

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Stockholders' Equity [Abstract]
Cash dividends paid on common stock (in dollars per share)	$ 0.23	$ 0.23

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities
Net Income (Loss)	$ 41,535	$ 50,300
Adjustments to reconcile net income to net cash provided by operating activities:
PCL	7,516	1,002
Depreciation and amortization	8,563	7,666
Net amortization of securities	1,373	1,812
Gains on sales of loans, net	(5,010)	(2,573)
Compensation expense, long-term incentive plan	2,238	1,715
Deferred income tax provision	28,490	335
Proceeds from sales of loans held for sale	263,634	216,327
Purchases and originations of loans held for sale	(247,476)	(269,863)
Originations of mortgage servicing rights	(2,977)	(2,646)
Earnings on bank-owned life insurance	(1,420)	(1,263)
Net change in other assets	(21,036)	303
Net change in other liabilities	(127,283)	7,390
Other operating activities, net	(6,690)	(7,946)
Net cash from operating activities	(58,543)	2,559
Investing Activities
Proceeds from maturities, prepayments and calls of securities held to maturity	24,000	23,930
Proceeds from maturities, prepayments and calls of securities available for sale	56,706	69,054
Purchases of securities held to maturity	(9,136)	0
Net change in federal funds sold and securities purchased under reverse repurchase agreements	0	4,000
Net change in member bank stock	(743)	(27,026)
Net change in LHFI	(114,096)	(295,239)
Purchases of premises and equipment	(5,050)	(17,095)
Proceeds from sales of premises and equipment	0	1,229
Proceeds from sales of other real estate	902	465
Purchases of software	(2,044)	(2,716)
Investments in tax credit and other partnerships	(1,848)	(5,912)
Net cash from investing activities	(51,309)	(249,310)
Financing Activities
Net change in deposits	(231,206)	346,013
Net change in federal funds purchased and securities sold under repurchase agreements	(12,530)	28,649
Net change in short-term borrowings	0	449,999
Payments on long-term FHLB advances	(5)	(5)
Payments under finance lease obligations	(99)	(342)
Common stock dividends	(14,207)	(14,158)
Shares withheld to pay taxes, long-term incentive plan	(1,383)	(1,048)
Net cash from financing activities	(259,430)	809,108
Net change in cash and cash equivalents	(369,282)	562,357
Cash and cash equivalents at beginning of period	975,543	734,787
Cash and cash equivalents at end of period	$ 606,261	$ 1,297,144

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 41,535	$ 50,300

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024
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

Business, Basis of Financial St

Business, Basis of Financial Statement Presentation and Principles of Consolidation	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business, Basis of Financial Statement Presentation and Principles of Consolidation	Note 1 – Business, Basis of Financial Statement Presentation and Principles of Consolidation Trustmark Corporation (Trustmark) is a bank holding company headquartered in Jackson, Mississippi. Through its subsidiaries, Trustmark operates as a financial services organization providing banking and financial solutions to corporate institutions and individual customers through offices in Alabama (includes the Georgia Loan Production Office), Florida, Mississippi, Tennessee and Texas. The consolidated financial statements include the accounts of Trustmark and all other entities in which Trustmark has a controlling financial interest. All significant intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the consolidated financial statements, and notes thereto, included in Trustmark’s Annual Report on Form 10-K for its fiscal year ended December 31, 2023 (2023 Annual Report). Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period. In the opinion of Management, all adjustments (consisting of normal recurring accruals) considered necessary for the fair presentation of these consolidated financial statements have been included. The preparation of financial statements in conformity with these accounting principles requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and income and expense during the reporting periods and the related disclosures. Although Management’s estimates contemplate current conditions and how they are expected to change in the future, it is reasonably possible that in 2024 actual conditions could vary from those anticipated, which could affect Trustmark’s financial condition and results of operations. Actual results could differ from those estimates. Subsequent Events On April 23, 2024, Trustmark National Bank (TNB) announced that it had entered into a definitive agreement to sell its wholly owned subsidiary, Fisher Brown Bottrell Insurance, Inc., (FBBI) to Marsh & McLennan Agency LLC (MMA) for $ 345.0 million in cash. The sale of FBBI, among the five largest bank-affiliated insurance brokerages in the nation and one of the largest agencies in the Southeast, is expected to allow Trustmark to capitalize on the strong valuation premiums in the insurance brokerage sector. The $ 345.0 million transaction value represents approximately 5.9 times FBBI’s 2023 revenue and 28.0 times net income. The estimated after-tax proceeds of $ 228.0 million are expected to be used to reposition Trustmark’s balance sheet to increase earnings, elevate profitability and enhance capital. TNB anticipates that the transaction, which is subject to standard closing conditions and regulatory approval, will close by the end of the second quarter of 2024. Upon consummation of this transaction, Trustmark will no longer engage in insurance brokerage activity and will no longer report an Insurance Segment in its periodic and other reports as filed with the SEC.

Securities Available for Sale a

Securities Available for Sale and Held to Maturity	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Securities Available for Sale and Held to Maturity	Note 2 – Securities Available for Sale and Held to Maturity The following tables are a summary of the amortized cost and estimated fair value of securities available for sale and held to maturity at March 31, 2024 and December 31, 2023 ($ in thousands): Securities Available for Sale Securities Held to Maturity March 31, 2024 Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. Treasury securities $ 396,289 $ — $ ( 23,865 ) $ 372,424 $ 29,261 $ — $ ( 515 ) $ 28,746 U.S. Government agency 6,017 — ( 423 ) 5,594 — — — — Obligations of states and — — — — 340 — — 340 Mortgage-backed securities Residential mortgage pass- Guaranteed by GNMA 25,343 6 ( 3,117 ) 22,232 18,387 — ( 750 ) 17,637 Issued by FNMA and 1,293,149 22 ( 163,650 ) 1,129,521 461,457 46 ( 21,935 ) 439,568 Other residential mortgage- Issued or guaranteed by 85,317 — ( 6,218 ) 79,099 146,447 — ( 10,731 ) 135,716 Commercial mortgage-backed Issued or guaranteed by 94,865 — ( 1,436 ) 93,429 759,133 13 ( 48,139 ) 711,007 Total $ 1,900,980 $ 28 $ ( 198,709 ) $ 1,702,299 $ 1,415,025 $ 59 $ ( 82,070 ) $ 1,333,014 Securities Available for Sale Securities Held to Maturity December 31, 2023 Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. Treasury Securities $ 396,179 $ — $ ( 23,811 ) $ 372,368 $ 29,068 $ — $ ( 26 ) $ 29,042 U.S. Government agency 6,207 1 ( 416 ) 5,792 — — — — Obligations of states and — — — — 340 — — 340 Mortgage-backed securities Residential mortgage pass- Guaranteed by GNMA 25,744 4 ( 2,613 ) 23,135 13,005 — ( 497 ) 12,508 Issued by FNMA and 1,338,256 32 ( 161,490 ) 1,176,798 469,593 — ( 18,205 ) 451,388 Other residential mortgage- Issued or guaranteed by 92,076 — ( 6,002 ) 86,074 154,466 — ( 10,113 ) 144,353 Commercial mortgage-backed Issued or guaranteed by 100,545 — ( 1,834 ) 98,711 759,807 51 ( 41,985 ) 717,873 Total $ 1,959,007 $ 37 $ ( 196,166 ) $ 1,762,878 $ 1,426,279 $ 51 $ ( 70,826 ) $ 1,355,504 During 2022, Trustmark reclassified a total of $ 766.0 million of securities available for sale to securities held to maturity. At the date of these transfers, the net unrealized holding loss on the available for sale securities totaled approximately $ 91.9 million ($ 68.9 million, net of tax). The securities were transferred at fair value, which became the cost basis for the securities held to maturity. The net unrealized holding loss will be amortized over the remaining life of the securities as a yield adjustment in a manner consistent with the amortization or accretion of the original purchase premium or discount on the associated security. There were no gains or losses recognized as a result of these transfers. At March 31, 2024 , the net unamortized, unrealized loss on transferred securities included in accumulated other comprehensive income (loss) in the accompanying balance sheet totaled $ 54.8 million compared to $ 57.6 million at December 31, 2023. ACL on Securities Securities Available for Sale Quarterly, Trustmark evaluates if any security has a fair value less than its amortized cost. Once these securities are identified, in order to determine whether a decline in fair value resulted from a credit loss or other factors, Trustmark performs further analysis. If Trustmark determines that a credit loss exists, the credit portion of the allowance is measured using a discounted cash flow (DCF) analysis using the effective interest rate as of the security’s purchase date. The amount of credit loss recorded by Trustmark is limited to the amount by which the amortized cost exceeds the fair value. The DCF analysis utilizes contractual maturities, as well as third-party credit ratings and cumulative default rates published annually by Moody’s Investor Service (Moody’s). At both March 31, 2024 and December 31, 2023 , the results of the analysis did not identify any securities that warranted DCF analysis, and no credit loss was recognized on any of the securities available for sale. Accrued interest receivable is excluded from the estimate of credit losses for securities available for sale. At both March 31, 2024 and December 31, 2023 , accrued interest receivable totaled $ 3.7 million for securities available for sale and was reported in other assets on the accompanying consolidated balance sheet. Securities Held to Maturity At both March 31, 2024 and December 31, 2023 , the potential for credit loss exposure for Trustmark's securities held to maturity was $ 340 thousand and consisted of municipal securities. After applying appropriate probability of default (PD) and loss given default (LGD) assumptions, the total amount of current expected credit losses was deemed immaterial. Therefore, no reserve was recorded at March 31, 2024 and December 31, 2023. Accrued interest receivable is excluded from the estimate of credit losses for securities held to maturity. At March 31, 2024 , accrued interest receivable totaled $ 2.7 million for securities held to maturity compared to $ 2.6 million at December 31, 2023 and was reported in other assets on the accompanying consolidated balance sheet. At both March 31, 2024 and December 31, 2023, Trustmark had no securities held to maturity that were past due 30 days or more as to principal or interest payments. Trustmark had no securities held to maturity classified as nonaccrual at March 31, 2024 and December 31, 2023 . Trustmark monitors the credit quality of securities held to maturity on a monthly basis through credit ratings. The following table presents the amortized cost of Trustmark’s securities held to maturity by credit rating, as determined by Moody’s, at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Aaa $ 1,414,685 $ 1,425,939 Not Rated (1) 340 340 Total $ 1,415,025 $ 1,426,279 (1) Not rated securities primarily consist of Mississippi municipal general obligations. The tables below include securities with gross unrealized losses for which an allowance for credit losses has not been recorded segregated by length of impairment at March 31, 2024 and December 31, 2023 ($ in thousands): Less than 12 Months 12 Months or More Total March 31, 2024 Estimated Gross Estimated Gross Estimated Gross U.S. Treasury securities $ 28,746 $ ( 515 ) $ 372,424 $ ( 23,865 ) $ 401,170 $ ( 24,380 ) U.S. Government agency obligations — — 5,594 ( 423 ) 5,594 ( 423 ) Mortgage-backed securities Residential mortgage pass-through Guaranteed by GNMA 14,632 ( 343 ) 24,950 ( 3,524 ) 39,582 ( 3,867 ) Issued by FNMA and FHLMC 303,034 ( 5,957 ) 1,259,726 ( 179,628 ) 1,562,760 ( 185,585 ) Other residential mortgage-backed Issued or guaranteed by FNMA, — — 214,805 ( 16,949 ) 214,805 ( 16,949 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, 1,616 ( 55 ) 800,447 ( 49,520 ) 802,063 ( 49,575 ) Total $ 348,028 $ ( 6,870 ) $ 2,677,946 $ ( 273,909 ) $ 3,025,974 $ ( 280,779 ) December 31, 2023 U.S. Treasury Securities $ 29,042 $ ( 26 ) $ 372,368 $ ( 23,811 ) $ 401,410 $ ( 23,837 ) U.S. Government agency obligations — — 5,791 ( 416 ) 5,791 ( 416 ) Mortgage-backed securities Residential mortgage pass-through Guaranteed by GNMA 9,381 ( 172 ) 25,967 ( 2,938 ) 35,348 ( 3,110 ) Issued by FNMA and FHLMC 309,466 ( 3,274 ) 1,311,865 ( 176,421 ) 1,621,331 ( 179,695 ) Other residential mortgage-backed Issued or guaranteed by FNMA, — — 230,368 ( 16,115 ) 230,368 ( 16,115 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, 1,656 ( 13 ) 812,520 ( 43,806 ) 814,176 ( 43,819 ) Total $ 349,545 $ ( 3,485 ) $ 2,758,879 $ ( 263,507 ) $ 3,108,424 $ ( 266,992 ) The unrealized losses shown above are due to increases in market rates over the yields available at the time of purchase of the underlying securities and not credit quality. Trustmark does not intend to sell these securities and it is more likely than not that Trustmark will not be required to sell the investments before recovery of their amortized cost bases, which may be at maturity. Securities Gains and Losses During the three months ended March 31, 2024 and 2023 , there were no gross realized gains or losses as a result of calls and dispositions of securities. Realized gains and losses are determined using the specific identification method and are included in noninterest income as securities gains (losses), net. Securities Pledged Securities with a carrying value of $ 2.291 billion and $ 2.321 billion at March 31, 2024 and December 31, 2023, respectively, were pledged to collateralize public deposits and securities sold under repurchase agreements and for other purposes as permitted by law. At both March 31, 2024 and December 31, 2023 , none of these securities were pledged under the Federal Reserve Discount Window program to provide additional contingency funding capacity. Contractual Maturities The amortized cost and estimated fair value of securities available for sale and held to maturity at March 31, 2024, by contractual maturity, are shown below ($ in thousands). Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities Securities Amortized Estimated Amortized Estimated Due in one year or less $ 99,995 $ 98,050 $ 340 $ 340 Due after one year through five years 296,508 274,584 29,261 28,746 Due after five years through ten years 2,236 2,021 — — Due after ten years 3,567 3,363 — — 402,306 378,018 29,601 29,086 Mortgage-backed securities 1,498,674 1,324,281 1,385,424 1,303,928 Total $ 1,900,980 $ 1,702,299 $ 1,415,025 $ 1,333,014

LHFI and ACL, LHFI

LHFI and ACL, LHFI	3 Months Ended
	Mar. 31, 2024
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
LHFI and ACL, LHFI	Note 3 – LHFI and ACL, LHFI At March 31, 2024 and December 31, 2023, LHFI consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Loans secured by real estate: Construction, land development and other land $ 617,008 $ 642,886 Other secured by 1-4 family residential properties 625,387 622,397 Secured by nonfarm, nonresidential properties 3,543,235 3,489,434 Other real estate secured 1,384,610 1,312,551 Other loans secured by real estate: Other construction 922,453 867,793 Secured by 1-4 family residential properties 2,266,094 2,282,318 Commercial and industrial loans 1,922,711 1,922,910 Consumer loans 159,340 165,734 State and other political subdivision loans 1,052,844 1,088,466 Other commercial loans and leases 564,261 556,035 LHFI 13,057,943 12,950,524 Less ACL 142,998 139,367 Net LHFI $ 12,914,945 $ 12,811,157 Accrued interest receivable is not included in the amortized cost basis of Trustmark’s LHFI. At March 31, 2024 and December 31, 2023 , accrued interest receivable for LHFI totaled $ 70.3 million and $ 71.0 million, respectively, with no related ACL and was reported in other assets on the accompanying consolidated balance sheet. Loan Concentrations Trustmark does not have any loan concentrations other than those reflected in the preceding table, which exceed 10 % of total LHFI. At March 31, 2024 , Trustmark’s geographic loan distribution was concentrated primarily in its five key market regions: Alabama, Florida, Mississippi, Tennessee and Texas. Accordingly, the ultimate collectability of a substantial portion of these loans is susceptible to changes in market conditions in these areas. Nonaccrual and Past Due LHFI No material interest income was recognized in the income statement on nonaccrual LHFI for each of the periods ended March 31, 2024 and 2023. The following tables provide the amortized cost basis of loans on nonaccrual status and loans past due 90 days or more still accruing interest at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Nonaccrual With No ACL Total Nonaccrual Loans Past Due 90 Days or More Still Accruing Loans secured by real estate: Construction, land development and other land $ 991 $ 1,809 $ — Other secured by 1-4 family residential properties 923 6,843 919 Secured by nonfarm, nonresidential properties 917 3,049 — Other real estate secured — 134 — Other loans secured by real estate: Other construction — 13,098 — Secured by 1-4 family residential properties 4,291 48,877 3,792 Commercial and industrial loans 36 23,089 49 Consumer loans — 238 483 Other commercial loans and leases — 1,214 — Total $ 7,158 $ 98,351 $ 5,243 December 31, 2023 Nonaccrual With No ACL Total Nonaccrual Loans Past Due 90 Days or More Still Accruing Loans secured by real estate: Construction, land development and other land $ 2,020 $ 2,642 $ — Other secured by 1-4 family residential properties 946 6,518 1,238 Secured by nonfarm, nonresidential properties 20,812 23,061 54 Other real estate secured — 158 106 Other loans secured by real estate: Other construction — 62 — Secured by 1-4 family residential properties 3,235 43,815 3,740 Commercial and industrial loans 79 22,303 24 Consumer loans — 243 628 Other commercial loans and leases — 1,206 — Total $ 27,092 $ 100,008 $ 5,790 The following tables provide an aging analysis of the amortized cost basis of past due LHFI (including nonaccrual LHFI) at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total LHFI Loans secured by real estate: Construction, land development and $ 354 $ 590 $ 1,011 $ 1,955 $ 615,053 $ 617,008 Other secured by 1-4 family residential 6,147 1,554 2,575 10,276 615,111 625,387 Secured by nonfarm, nonresidential 695 711 892 2,298 3,540,937 3,543,235 Other real estate secured — — — — 1,384,610 1,384,610 Other loans secured by real estate: Other construction — 13,038 — 13,038 909,415 922,453 Secured by 1-4 family residential properties 14,706 7,246 25,361 47,313 2,218,781 2,266,094 Commercial and industrial loans 12,207 446 19,018 31,671 1,891,040 1,922,711 Consumer loans 1,616 548 512 2,676 156,664 159,340 State and other political subdivision loans 972 — — 972 1,051,872 1,052,844 Other commercial loans and leases 1,522 116 37 1,675 562,586 564,261 Total $ 38,219 $ 24,249 $ 49,406 $ 111,874 $ 12,946,069 $ 13,057,943 December 31, 2023 Past Due 30-59 Days 60-89 Days 90 Days More Total Past Due Current Total LHFI Loans secured by real estate: Construction, land development and $ 93 $ 507 $ 2,362 $ 2,962 $ 639,924 $ 642,886 Other secured by 1-4 family residential 4,493 1,687 2,716 8,896 613,501 622,397 Secured by nonfarm, nonresidential 1,531 1,063 727 3,321 3,486,113 3,489,434 Other real estate secured 126 — 207 333 1,312,218 1,312,551 Other loans secured by real estate: Other construction 62 — — 62 867,731 867,793 Secured by 1-4 family residential properties 19,298 9,327 22,164 50,789 2,231,529 2,282,318 Commercial and industrial loans 11,881 484 499 12,864 1,910,046 1,922,910 Consumer loans 2,112 772 647 3,531 162,203 165,734 State and other political subdivision loans 152 — — 152 1,088,314 1,088,466 Other commercial loans and leases 1,247 58 — 1,305 554,730 556,035 Total $ 40,995 $ 13,898 $ 29,322 $ 84,215 $ 12,866,309 $ 12,950,524 Modified LHFI Occasionally, Trustmark modifies loans for borrowers experiencing financial difficulties by providing payment concessions, interest-only payments for an extended period of time, maturity extensions or interest rate reductions. Other concessions may arise from court proceedings or may be imposed by law. In some cases, Trustmark provides multiple types of concessions on one loan. The following tables present the amortized cost of LHFI at the end of each of the periods presented of loans modified to borrowers experiencing financial difficulty disaggregated by class of loan and type of modification ($ in thousands). The percentage of the amortized cost basis of LHFI that were modified to borrowers in financial distress as compared to the amortized cost basis of each class of LHFI is also presented below: Three Months Ended March 31, 2024 Term Extension % of Total Class of Loan Loans secured by real estate: Other secured by 1-4 family residential $ 1,461 0.23 % Other loans secured by real estate: Secured by 1-4 family residential properties 813 0.04 % Total $ 2,274 0.02 % Three Months Ended March 31, 2023 Term Extension % of Total Class of Loan Loans secured by real estate: Secured by nonfarm, nonresidential $ 384 0.01 % Other loans secured by real estate: Secured by 1-4 family residential properties 492 0.02 % Total $ 876 0.01 % The following tables detail the financial effect of the loan modifications presented above to borrowers experiencing financial difficulty for the periods presented: Three Months Ended March 31, 2024 Financial Effect Term Extension Loans secured by real estate: Other secured by 1-4 family residential properties Modified one loan and multiple lines of credit to amortize over 24 month terms. Other loans secured by real estate: Secured by 1-4 family residential properties Extended the amortization periods on six loans by a weighted-average of 2.99 years. Three Months Ended March 31, 2023 Financial Effect Term Extension Loans secured by real estate: Secured by nonfarm, nonresidential properties Renewed with an extended amortization period and lowered the monthly payment amount for the borrower. Other loans secured by real estate: Secured by 1-4 family residential properties Extended the amortization periods on four loans by a weighted-average of 14 years, which reduced the aggregate monthly payment amounts for the borrowers. Trustmark had no unused commitments on modified loans to borrowers experiencing financial difficulty at March 31, 2024. During the three months ended March 31, 2024 and 2023, payment defaults of LHFI that were modified within the twelve months prior to that default to borrowers experiencing financial difficulty were immaterial. Trustmark has utilized loans 90 days or more past due to define payment default in determining modified loans that have subsequently defaulted. If Trustmark determines that a modified loan (or a portion of a loan) has subsequently been deemed uncollectible, the loan (or a portion of the loan) is charged off against the ACL, LHFI. Trustmark closely monitors the performance of loans that are modified to borrowers experiencing financial difficulty to understand the effectiveness of its modification efforts. The following tables provide details of the performance of such LHFI that have been modified during the periods presented ($ in thousands): Three Months Ended March 31, 2024 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total Loans secured by real estate: Other secured by 1-4 family residential $ — $ — $ — $ — $ 1,461 $ 1,461 Other loans secured by real estate: Secured by 1-4 family residential properties — — — — 813 813 Total $ — $ — $ — $ — $ 2,274 $ 2,274 Three Months Ended March 31, 2023 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total Loans secured by real estate: Secured by nonfarm, nonresidential $ — $ — $ — $ — $ 384 $ 384 Other loans secured by real estate: Secured by 1-4 family residential properties — — — — 492 492 Total $ — $ — $ — $ — $ 876 $ 876 Collateral-Dependent Loans The following tables present the amortized cost basis of collateral-dependent loans by class of loans and collateral type as of March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Real Estate Vehicles Miscellaneous Total Loans secured by real estate: Construction, land development and $ 1,539 $ — $ — $ 1,539 Other secured by 1-4 family 923 — — 923 Secured by nonfarm, nonresidential 917 — — 917 Other loans secured by real estate: Other construction 13,038 — — 13,038 Secured by 1-4 family residential 4,291 — — 4,291 Commercial and industrial loans 20 36 21,154 21,210 Other commercial loans and leases — — 1,022 1,022 Total $ 20,728 $ 36 $ 22,176 $ 42,940 December 31, 2023 Real Estate Vehicles Miscellaneous Total Loans secured by real estate: Construction, land development and $ 2,020 $ — $ — $ 2,020 Other secured by 1-4 family 946 — — 946 Secured by nonfarm, nonresidential 20,812 — — 20,812 Other loans secured by real estate: Secured by 1-4 family residential 3,235 — — 3,235 Commercial and industrial loans 38 41 21,023 21,102 Other commercial loans and leases — — 967 967 Total $ 27,051 $ 41 $ 21,990 $ 49,082 A loan is collateral dependent when the borrower is experiencing financial difficulty and repayment of the loan is expected to be provided substantially through the sale of the collateral. The following provides a qualitative description by class of loan of the collateral that secures Trustmark’s collateral-dependent LHFI: • Loans secured by real estate – Loans within these loan classes are secured by liens on real estate properties. There have been no significant changes to the collateral that secures these financial assets during the period. • Other loans secured by real estate – Loans within these loan classes are secured by liens on real estate properties. There have been no significant changes to the collateral that secures these financial assets during the period. • Commercial and industrial loans – Loans within this loan class are primarily secured by inventory, accounts receivables, equipment and other non-real estate collateral. There have been no significant changes to the collateral that secures these financial assets during the period. • State and other political subdivision loans – Loans within this loan class are secured by liens on real estate properties or other non-real estate collateral. There have been no significant changes to the collateral that secures these financial assets during the period. • Other commercial loans – Loans within this loan class are secured by non-real estate collateral. There have been no significant changes to the collateral that secures these financial assets during the period. Credit Quality Indicators Trustmark’s LHFI portfolio credit quality indicators focus on six key quality ratios that are compared against bank tolerances. The loan indicators are total classified outstanding, total criticized outstanding, nonperforming loans, nonperforming assets, delinquencies and net loan losses. Due to the homogeneous nature of consumer loans, Trustmark does not assign a formal internal risk rating to each credit and therefore the criticized and classified measures are primarily composed of commercial loans. In addition to monitoring portfolio credit quality indicators, Trustmark also measures how effectively the lending process is being managed and risks are being identified. As part of an ongoing monitoring process, Trustmark grades the commercial portfolio segment as it relates to credit file completion and financial statement exceptions, underwriting, collateral documentation and compliance with law as shown below: • Credit File Completeness and Financial Statement Exceptions – evaluates the quality and condition of credit files in terms of content and completeness and focuses on efforts to obtain and document sufficient information to determine the quality and status of credits. Also included is an evaluation of the systems/procedures used to ensure compliance with policy. • Underwriting – evaluates whether credits are adequately analyzed, appropriately structured and properly approved within loan policy requirements. A properly approved credit is approved by an adequate authority in a timely manner with all conditions of approval fulfilled. Total policy exceptions measure the level of underwriting and other policy exceptions within a portfolio segment. • Collateral Documentation – focuses on the adequacy of documentation to perfect Trustmark’s collateral position and substantiate collateral value. Collateral exceptions measure the level of documentation exceptions within a portfolio segment. Collateral exceptions occur when certain collateral documentation is either not present or not current. • Compliance with Law – focuses on underwriting, documentation, approval and reporting in compliance with banking laws and regulations. Primary emphasis is directed to the Financial Institutions Reform, Recovery and Enforcement Act of 1989 (FIRREA), Regulation O requirements and regulations governing appraisals. Commercial Credits Trustmark has established a loan grading system that consists of ten individual credit risk grades (risk ratings) that encompass a range from loans where the expectation of loss is negligible to loans where loss has been established. The model is based on the risk of default for an individual credit and establishes certain criteria to delineate the level of risk across the ten unique credit risk grades. Credit risk grade definitions are as follows: • Risk Rate (RR) 1 through RR 6 – Grades one through six represent groups of loans that are not subject to criticism as defined in regulatory guidance. Loans in these groups exhibit characteristics that represent low to moderate risk measured by using a variety of credit risk criteria such as cash flow coverage, debt service coverage, balance sheet leverage, liquidity, management experience, industry position, prevailing economic conditions, support from secondary sources of repayment and other credit factors that may be relevant to a specific loan. In general, these loans are supported by properly margined collateral and guarantees of principal parties. • Other Assets Especially Mentioned (Special Mention) (RR 7) – a loan that has a potential weakness that if not corrected will lead to a more severe rating. This rating is for credits that are currently protected but potentially weak because of an adverse feature or condition that if not corrected will lead to a further downgrade. • Substandard (RR 8) – a loan that has at least one identified weakness that is well defined. This rating is for credits where the primary sources of repayment are not viable at the time of evaluation or where either the capital or collateral is not adequate to support the loan and the secondary means of repayment do not provide a sufficient level of support to offset the identified weakness. Loss potential exists in the aggregate amount of substandard loans but does not necessarily exist in individual loans. • Doubtful (RR 9) – a loan with an identified weakness that does not have a valid secondary source of repayment. Generally, these credits have an impaired primary source of repayment and secondary sources are not sufficient to prevent a loss in the credit. The exact amount of the loss has not been determined at this time. • Loss (RR 10) – a loan or a portion of a loan that is deemed to be uncollectible. By definition, credit risk grades special mention (RR 7), substandard (RR 8), doubtful (RR 9) and loss (RR 10) are criticized loans while substandard (RR 8), doubtful (RR 9) and loss (RR 10) are classified loans. These definitions are standardized by the bank regulatory agencies and are generally equally applied to each individual lending institution. The remaining credit risk grades are considered pass credits and are solely defined by Trustmark. To enhance this process, Trustmark has determined that certain loans will be individually assessed, and a formal analysis will be performed and based upon the analysis the loan will be written down to the net realizable value. Trustmark will individually assess and remove loans from the pool in the following circumstances: • Commercial nonaccrual loans with total exposure of $ 500 thousand (excluding those portions of the debt that are government guaranteed or are secured by Trustmark deposits or marketable securities) or more. • Any loan that is believed to not share similar risk characteristics with the rest of the pool will be individually assessed. Otherwise, the loan will be left within the pool based on the results of the assessment. • Commercial accruing loans deemed to be a modified loan to a borrower experiencing financial difficulty with total exposure of $ 500 thousand (excluding those portions of the debt that are government guaranteed or are secured by Trustmark deposits or marketable securities) or more. If the loan is believed to not share similar risk characteristics with the rest of the loan pool, the loan will be individually assessed. Otherwise, the loan will be left within the pool and monitored on an ongoing basis. Each loan officer assesses the appropriateness of the internal risk rating assigned to their credits on an ongoing basis. Trustmark’s Asset Review area conducts independent credit quality reviews of the majority of Trustmark’s commercial loan portfolio both on the underlying credit quality of each individual loan class as well as the adherence to Trustmark’s loan policy and the loan administration process. In addition to the ongoing internal risk rate monitoring described above, Trustmark’s Credit Quality Review Committee meets monthly and performs a review of all loans of $ 100 thousand or more that are either delinquent 30 days or more or on nonaccrual. This review includes recommendations regarding risk ratings, accrual status, charge-offs and appropriate servicing officer as well as evaluation of problem credits for determination of modified status. Quarterly, the Credit Quality Review Committee reviews and modifies continuous action plans for all credits risk rated seven or worse for relationships of $100 thousand or more. In addition, periodic reviews of significant development, construction, multi-family, nonowner-occupied and other commercial credits are performed. These reviews assess each particular project with respect to location, project valuations, progress of completion, leasing status, current financial information, rents, operating expenses, cash flow, adherence to budget and projections and other information that is pertinent to the particular type of credit as applicable. Summary results are reviewed by Senior and Regional Credit Officers in addition to the Chief Credit Officer with a determination made as to the appropriateness of existing risk ratings and accrual status. Consumer Credits The Retail Credit Review Committee, Management Credit Policy Committee and the Enterprise Risk Committee review the volume and percentage of consumer loan delinquencies and losses to monitor the overall quality of the consumer portfolio. Trustmark monitors the levels and severity of past due consumer LHFI on a daily basis through its collection activities. A detailed assessment of consumer LHFI delinquencies is performed monthly at both a product and market level. The tables below present the amortized cost basis of loans by credit quality indicator and class of loans based on analyses performed at March 31, 2024 and December 31, 2023 ($ in thousands): Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Commercial LHFI Loans secured by real estate: Construction, land Pass - RR 1 through RR 6 $ 98,031 $ 268,068 $ 77,825 $ 30,055 $ 10,227 $ 3,425 $ 49,281 $ 536,912 Special Mention - RR 7 — — — 354 — — — 354 Substandard - RR 8 — 265 265 1,239 18 19 — 1,806 Doubtful - RR 9 — — — — — — — — Total 98,031 268,333 78,090 31,648 10,245 3,444 49,281 539,072 Current period gross — — — — — ( 24 ) — ( 24 ) Other secured by 1-4 family Pass - RR 1 through RR 6 $ 6,379 $ 32,381 $ 28,573 $ 25,941 $ 13,447 $ 9,086 $ 7,889 $ 123,696 Special Mention - RR 7 28 — 53 44 8 — — 133 Substandard - RR 8 59 165 646 155 21 364 34 1,444 Doubtful - RR 9 — — — — — — — — Total 6,466 32,546 29,272 26,140 13,476 9,450 7,923 125,273 Current period gross — — — — — ( 12 ) — ( 12 ) Secured by nonfarm, Pass - RR 1 through RR 6 $ 167,040 $ 492,579 $ 944,333 $ 505,580 $ 574,763 $ 616,719 $ 132,679 $ 3,433,693 Special Mention - RR 7 — 4,260 19,546 — 133 24,979 — 48,918 Substandard - RR 8 4,794 1,521 1,800 27,323 10,711 13,266 1,129 60,544 Doubtful - RR 9 18 — — — — 57 — 75 Total 171,852 498,360 965,679 532,903 585,607 655,021 133,808 3,543,230 Current period gross — — — ( 2,412 ) — ( 16 ) — ( 2,428 ) Other real estate secured: Pass - RR 1 through RR 6 $ 116,981 $ 114,564 $ 539,374 $ 309,788 $ 209,292 $ 46,190 $ 8,758 $ 1,344,947 Special Mention - RR 7 — — — 64 — 35,876 — 35,940 Substandard - RR 8 99 — 3,028 — 268 31 — 3,426 Doubtful - RR 9 — 45 — — — — — 45 Total 117,080 114,609 542,402 309,852 209,560 82,097 8,758 1,384,358 Current period gross — — — — — — — — Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Commercial LHFI Other loans secured by real Other construction: Pass - RR 1 through RR 6 $ 40,364 $ 208,241 $ 494,239 $ 149,994 $ 16,177 $ — $ 340 $ 909,355 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 60 — 13,038 — — — — 13,098 Doubtful - RR 9 — — — — — — — — Total 40,424 208,241 507,277 149,994 16,177 — 340 922,453 Current period gross — — — — — — — — Commercial and industrial Pass - RR 1 through RR 6 $ 188,609 $ 459,063 $ 323,119 $ 124,545 $ 58,584 $ 70,060 $ 538,649 $ 1,762,629 Special Mention - RR 7 — 12,270 22,693 2,136 554 1,323 20,264 59,240 Substandard - RR 8 2,240 4,831 47,455 13,725 11,842 350 19,884 100,327 Doubtful - RR 9 — — 336 155 — 23 1 515 Total 190,849 476,164 393,603 140,561 70,980 71,756 578,798 1,922,711 Current period gross — ( 3 ) ( 225 ) ( 294 ) ( 8 ) ( 54 ) — ( 584 ) State and other political Pass - RR 1 through RR 6 $ 16,902 $ 122,135 $ 243,470 $ 168,190 $ 96,337 $ 401,066 $ 4,744 $ 1,052,844 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 — — — — — — — — Doubtful - RR 9 — — — — — — — — Total 16,902 122,135 243,470 168,190 96,337 401,066 4,744 1,052,844 Current period gross — — — — — — — — Other commercial loans and leases: Pass - RR 1 through RR 6 $ 44,336 $ 193,567 $ 23,760 $ 26,671 $ 18,877 $ 40,003 $ 214,044 $ 561,258 Special Mention - RR 7 — — — 120 193 — — 313 Substandard - RR 8 992 90 123 25 — — 1,460 2,690 Doubtful - RR 9 — — — — — — — — Total 45,328 193,657 23,883 26,816 19,070 40,003 215,504 564,261 Current period gross — — ( 28 ) — — ( 25 ) — ( 53 ) Total commercial $ 686,932 $ 1,914,045 $ 2,783,676 $ 1,386,104 $ 1,021,452 $ 1,262,837 $ 999,156 $ 10,054,202 Total commercial LHFI $ — $ ( 3 ) $ ( 253 ) $ ( 2,706 ) $ ( 8 ) $ ( 131 ) $ — $ ( 3,101 ) Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Consumer LHFI Loans secured by real estate: Construction, land Current $ 4,808 $ 46,918 $ 15,604 $ 5,300 $ 1,165 $ 2,497 $ 1,562 $ 77,854 Past due 30-89 days — 34 — — — 39 — 73 Past due 90 days or more — — — — — — — — Nonaccrual — — — 6 — 3 — 9 Total 4,808 46,952 15,604 5,306 1,165 2,539 1,562 77,936 Current period gross — — — — — — — — Other secured by 1-4 family Current $ 8,491 $ 24,784 $ 10,059 $ 5,482 $ 4,202 $ 10,754 $ 424,148 $ 487,920 Past due 30-89 days — 30 254 169 60 286 4,451 5,250 Past due 90 days or more — — 5 — 100 48 684 837 Nonaccrual — 7 87 46 10 586 5,371 6,107 Total 8,491 24,821 10,405 5,697 4,372 11,674 434,654 500,114 Current period gross — — ( 5 ) — — — ( 59 ) ( 64 ) Secured by nonfarm, Current $ — $ — $ — $ 5 $ — $ — $ — $ 5 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — — 5 — — — 5 Current period gross — — — — — — — — Other real estate secured: Current $ 131 $ — $ — $ — $ 75 $ 46 $ — $ 252 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total 131 — — — 75 46 — 252 Current period gross — — — — — — — — Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Consumer LHFI Other loans secured by real Secured by 1-4 family Current $ 33,184 $ 249,825 $ 871,791 $ 506,872 $ 178,382 $ 355,532 $ — $ 2,195,586 Past due 30-89 days — 2,410 9,575 2,777 830 2,246 — 17,838 Past due 90 days or more — 527 1,175 1,052 127 911 — 3,792 Nonaccrual — 1,765 17,942 12,782 6,080 10,309 — 48,878 Total 33,184 254,527 900,483 523,483 185,419 368,998 — 2,266,094 Current period gross — ( 59 ) ( 315 ) ( 29 ) — ( 8 ) — ( 411 ) Consumer loans: Current $ 20,996 $ 43,982 $ 26,201 $ 8,570 $ 2,098 $ 840 $ 53,867 $ 156,554 Past due 30-89 days 348 518 288 122 1 5 784 2,066 Past due 90 days or more 19 58 66 4 8 — 328 483 Nonaccrual — 64 56 77 19 — 21 237 Total 21,363 44,622 26,611 8,773 2,126 845 55,000 159,340 Current period gross ( 1,544 ) ( 282 ) ( 122 ) ( 20 ) ( 27 ) — ( 753 ) ( 2,748 ) Total consumer LHFI $ 67,977 $ 370,922 $ 953,103 $ 543,264 $ 193,157 $ 384,102 $ 491,216 $ 3,003,741 Total consumer LHFI $ ( 1,544 ) $ ( 341 ) $ ( 442 ) $ ( 49 ) $ ( 27 ) $ ( 8 ) $ ( 812 ) $ ( 3,223 ) Total LHFI $ 754,909 $ 2,284,967 $ 3,736,779 $ 1,929,368 $ 1,214,609 $ 1,646,939 $ 1,490,372 $ 13,057,943 Total current period $ ( 1,544 ) $ ( 344 ) $ ( 695 ) $ ( 2,755 ) $ ( 35 ) $ ( 139 ) $ ( 812 ) $ ( 6,324 ) Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Commercial LHFI Loans secured by real estate: Construction, land Pass - RR 1 through RR 6 $ 359,813 $ 98,742 $ 35,095 $ 10,591 $ 2,036 $ 1,961 $ 52,351 $ 560,589 Special Mention - RR 7 — — 360 — — — — 360 Substandard - RR 8 606 336 1,512 19 — 21 — 2,494 Doubtful - RR 9 — — — — — 24 — 24 Total 360,419 99,078 36,967 10,610 2,036 2,006 52,351 563,467 Current period gross — ( 4 ) ( 10 ) — ( 228 ) — — ( 242 ) Other secured by 1-4 family Pass - RR 1 through RR 6 $ 33,072 $ 30,760 $ 29,159 $ 14,309 $ 8,084 $ 2,822 $ 10,077 $ 128,283 Special Mention - RR 7 — 82 48 10 — — — 140 Substandard - RR 8 220 625 157 22 80 306 98 1,508 Doubtful - RR 9 — — — — — — — — Total 33,292 31,467 29,364 14,341 8,164 3,128 10,175 129,931 Current period gross — — ( 24 ) — — ( 6 ) — ( 30 ) Secured by nonfarm, Pass - RR 1 through RR 6 $ 501,327 $ 919,519 $ 526,412 $ 596,240 $ 323,687 $ 369,250 $ 129,142 $ 3,365,577 Special Mention - RR 7 4,271 14,930 — 138 23,966 — — 43,305 Substandard - RR 8 6,332 1,964 47,491 10,809 8,614 5,200 48 80,458 Doubtful - RR 9 21 — — — 53 13 — 87 Total 511,951 936,413 573,903 607,187 356,320 374,463 129,190 3,489,427 Current period gross — ( 39 ) ( 82 ) — ( 19 ) ( 138 ) — ( 278 ) Other real estate secured: Pass - RR 1 through RR 6 $ 194,141 $ 447,200 $ 332,818 $ 209,757 $ 56,024 $ 11,080 $ 8,880 $ 1,259,900 Special Mention - RR 7 126 2,076 — — 35,881 — — 38,083 Substandard - RR 8 — 14,064 — 290 — 39 — 14,393 Doubtful - RR 9 42 — — — — — — 42 Total 194,309 463,340 332,818 210,047 91,905 11,119 8,880 1,312,418 Current period gross — — — — — — — — Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Commercial LHFI Other loans secured by real Other construction Pass - RR 1 through RR 6 $ 179,676 $ 518,062 $ 149,883 $ 14,062 $ — $ 6 $ 6,042 $ 867,731 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 62 — — — — — — 62 Doubtful - RR 9 — — — — — — — — Total 179,738 518,062 149,883 14,062 — 6 6,042 867,793 Current period gross ( 61 ) — ( 3,392 ) — — — — ( 3,453 ) Commercial and industrial Pass - RR 1 through RR 6 $ 497,730 $ 474,737 $ 158,659 $ 80,646 $ 31,876 $ 44,972 $ 537,527 $ 1,826,147 Special Mention - RR 7 12,570 10,141 3,149 1,381 110 — 126 27,477 Substandard - RR 8 4,797 16,872 13,909 11,958 40 80 21,528 69,184 Doubtful - RR 9 6 58 1 — — 25 12 102 Total 515,103 501,808 175,718 93,985 32,026 45,077 559,193 1,922,910 Current period gross ( 42 ) ( 1,071 ) ( 700 ) ( 138 ) ( 95 ) ( 108 ) ( 7 ) ( 2,161 ) State and other political Pass - RR 1 through RR 6 $ 152,157 $ 247,034 $ 174,812 $ 99,786 $ 32,118 $ 377,225 $ 5,334 $ 1,088,466 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 — — — — — — — — Doubtful - RR 9 — — — — — — — — Total 152,157 247,034 174,812 99,786 32,118 377,225 5,334 1,088,466 Current period gross — — — — — — — — Other commercial loans and leases: Pass - RR 1 through RR 6 $ 211,402 $ 48,947 $ 30,071 $ 21,377 $ 32,837 $ 8,468 $ 201,339 $ 554,441 Special Mention - RR 7 — — — 208 — — 20 228 Substandard - RR 8 106 211 42 — — — 987 1,346 Doubtful - RR 9 — — — — — 20 — 20 Total 211,508 49,158 30,113 21,585 32,837 8,488 202,346 556,035 Current period gross ( 40 ) ( 248 ) — ( 26 ) — — — ( 314 ) Total commercial $ 2,158,477 $ 2,846,360 $ 1,503,578 $ 1,071,603 $ 555,406 $ 821,512 $ 973,511 $ 9,930,447 Total commercial LHFI $ ( 143 ) $ ( 1,362 ) $ ( 4,208 ) $ ( 164 ) $ ( 342 ) $ ( 252 ) $ ( 7 ) $ ( 6,478 ) Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Consumer LHFI Loans secured by real estate: Construction, land Current $ 44,912 $ 23,110 $ 5,973 $ 1,203 $ 1,082 $ 1,864 $ 653 $ 78,797 Past due 30-89 days — 250 — — 30 191 — 471 Past due 90 days or more — — — — — — — — Nonaccrual — — 148 — — 3 — 151 Total 44,912 23,360 6,121 1,203 1,112 2,058 653 79,419 Current period gross — — — — — — — — Other secured by 1-4 family Current $ 29,636 $ 11,366 $ 5,733 $ 4,471 $ 4,313 $ 7,674 $ 417,383 $ 480,576 Past due 30-89 days 225 68 74 4 51 220 4,292 4,934 Past due 90 days or more — 264 — — — 41 934 1,239 Nonaccrual 8 76 48 8 — 616 4,961 5,717 Total 29,869 11,774 5,855 4,483 4,364 8,551 427,570 492,466 Current period gross — ( 100 ) ( 9 ) ( 2 ) ( 10 ) ( 22 ) ( 147 ) ( 290 ) Secured by nonfarm, Current $ — $ — $ 7 $ — $ — $ — $ — $ 7 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — 7 — — — — 7 Current period gross — — — — — — — — Other real estate secured: Current $ — $ — $ — $ 78 $ — $ 55 $ — $ 133 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — — 78 — 55 — 133 Current period gross — — — — — — — — Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Consumer LHFI Other loans secured by real Secured by 1-4 family Current $ 258,800 $ 878,893 $ 516,324 $ 180,272 $ 98,552 $ 277,664 $ — $ 2,210,505 Past due 30-89 days 3,370 11,293 5,513 2,121 298 1,664 — 24,259 Past due 90 days or more 376 1,219 1,208 682 — 255 — 3,740 Nonaccrual 678 15,586 11,452 4,884 1,848 9,366 — 43,814 Total 263,224 906,991 534,497 187,959 100,698 288,949 — 2,282,318 Current period gross ( 64 ) ( 930 ) ( 217 ) ( 104 ) — ( 142 ) — ( 1,457 ) Consumer loans: Current $ 59,496 $ 32,767 $ 10,698 $ 2,604 $ 917 $ 294 $ 55,321 $ 162,097 Past due 30-89 days 1,274 475 134 34 5 5 839 2,766 Past due 90 days or more 64 44 3 1 — — 516 628 Nonaccrual 44 65 84 26 — — 24 243 Total 60,878 33,351 10,919 2,665 922 299 56,700 165,734 Current period gross ( 6,138 ) ( 559 ) ( 167

Mortgage Banking

Mortgage Banking	3 Months Ended
	Mar. 31, 2024
Mortgage Banking [Abstract]
Mortgage Banking	Note 4 – Mortgage Banking MSR The activity in the MSR is detailed in the table below for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 131,870 $ 129,677 Origination of servicing assets 2,977 2,646 Change in fair value: Due to market changes 5,123 ( 3,972 ) Due to run-off ( 1,926 ) ( 1,145 ) Balance at end of period $ 138,044 $ 127,206 Trustmark determines the fair value of the MSR using a valuation model administered by a third party that calculates the present value of estimated future net servicing income. Trustmark considers the conditional prepayment rate (CPR), which is an estimated loan prepayment rate that uses historical prepayment rates for previous loans similar to the loans being evaluated, the float rate, which is the interest rate earned on escrow balances, and the discount rate as some of the primary assumptions used in determining the fair value of the MSR. An increase in either the CPR or discount rate assumption will result in a decrease in the fair value of the MSR, while a decrease in either assumption will result in an increase in the fair value of the MSR. An increase in the float rate will result in an increase in the fair value of the MSR, while a decrease in the float rate will result in a decrease in the fair value of the MSR. At both March 31, 2024 and 2023, the fair value of the MSR included an assumed average prepayment speed of 8 CPR and an average discount rate of 10.08 %. Mortgage Loans Serviced/Sold During the first three months of 2024 and 2023 , Trustmark sold $ 258.3 million and $ 213.8 million, respectively, of residential mortgage loans. Gains on these sales were recorded as noninterest income in mortgage banking, net and totaled $ 5.0 million for the first three months of 2024 compared to $ 3.8 million for the first three months of 2023. The table below details the mortgage loans sold and serviced for others at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Federal National Mortgage Association $ 4,831,183 $ 4,826,028 Government National Mortgage Association 3,557,236 3,510,983 Federal Home Loan Mortgage Corporation 137,725 112,352 Other 27,090 28,012 Total mortgage loans sold and serviced for others $ 8,553,234 $ 8,477,375 Trustmark is subject to losses in its loan servicing portfolio due to loan foreclosures. Trustmark has obligations to either repurchase the outstanding principal balance of a loan or make the purchaser whole for the economic benefits of a loan if it is determined that the loan sold was in violation of representations or warranties made by Trustmark at the time of the sale, herein referred to as mortgage loan servicing putback expenses. Such representations and warranties typically include those made regarding loans that had missing or insufficient file documentation, loans that do not meet investor guidelines, loans in which the appraisal does not support the value and/or loans obtained through fraud by the borrowers or other third parties. Generally, putback requests may be made until the loan is paid in full. However, mortgage loans delivered to Federal National Mortgage Association (FNMA) and Federal Home Loan Mortgage Corporation (FHLMC) on or after January 1, 2013 are subject to the Representations and Warranties Framework, which provides certain instances in which FNMA and FHLMC will not exercise their remedies, including a putback request, for breaches of certain selling representations and warranties, such as payment history and quality control review. When a putback request is received, Trustmark evaluates the request and takes appropriate actions based on the nature of the request. Trustmark is required by FNMA and FHLMC to provide a response to putback requests within 60 days of the date of receipt. The total mortgage loan servicing putback expenses are included in other expense. At both March 31, 2024 and 2023 , Trustmark had a reserve for mortgage loan servicing putback expenses of $ 500 thousand. There is inherent uncertainty in reasonably estimating the requirement for reserves against potential future mortgage loan servicing putback expenses. Future putback expenses are dependent on many subjective factors, including the review procedures of the purchasers and the potential refinance activity on loans sold with servicing released and the subsequent consequences under the representations and warranties. Trustmark believes that it has appropriately reserved for potential mortgage loan servicing putback requests.

Other Real Estate

Other Real Estate	3 Months Ended
	Mar. 31, 2024
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
Other Real Estate	Note 5 – Other Real Estate At March 31, 2024, Trustmark’s geographic other real estate distribution was primarily concentrated in its Alabama, Mississippi and Texas market regions. The ultimate recovery of a substantial portion of the carrying amount of other real estate is susceptible to changes in market conditions in this area. For the periods presented, changes and gains (losses), net on other real estate were as follows ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 6,867 $ 1,986 Additions 2,228 300 Disposals ( 957 ) ( 542 ) (Write-downs) recoveries ( 518 ) ( 60 ) Balance at end of period $ 7,620 $ 1,684 Gains (losses), net on the sale of other real estate included in $ ( 55 ) $ ( 77 ) At March 31, 2024 and December 31, 2023, other real estate by type of property consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 1-4 family residential properties $ 3,619 $ 1,977 Nonfarm, nonresidential properties 3,946 4,835 Other real estate properties 55 55 Total other real estate $ 7,620 $ 6,867 At March 31, 2024 and December 31, 2023, other real estate by geographic location consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Alabama $ 1,050 $ 1,397 Florida 71 — Mississippi (1) 2,870 1,242 Tennessee (2) 86 — Texas 3,543 4,228 Total other real estate $ 7,620 $ 6,867 (1) Mississippi includes Central and Southern Mississippi Regions. (2) Tennessee includes Memphis, Tennessee and Northern Mississippi Regions. At March 31, 2024 , the balance of other real estate included $ 3.6 million of foreclosed residential real estate properties recorded as a result of obtaining physical possession of the property compared to $ 2.0 million at December 31, 2023. At March 31, 2024 and December 31, 2023, the recorded investment of consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process was $ 9.8 million and $ 6.4 million, respectively.

Leases

Leases	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
Leases	Note 6 – Leases Lessor Arrangements Trustmark leases certain types of machinery and equipment to its customers through sales-type and direct financing leases as part of its equipment financing portfolio. These leases generally have remaining lease terms of two to nine years , some of which include renewal options and/or options for the lessee to purchase the leased property near or at the end of the lease term. Trustmark recognized interest income from its sales-type and direct financing leases of $ 2.4 million for the three months ended March 31, 2024. Trustmark does not have any significant operating leases in which it is the lessor. The table below summarizes the components of Trustmark's net investment in its sales-type and direct financing leases for the periods presented ($ in thousands): March 31, 2024 December 31, 2023 Leases receivable $ 202,112 $ 161,319 Unearned income ( 35,463 ) ( 29,011 ) Initial direct costs 1,737 1,326 Unguaranteed lease residual 5,577 4,101 Total net investment $ 173,963 $ 137,735 The table below details the minimum future lease payments for Trustmark's leases receivable at March 31, 2024 ($ in thousands): March 31, 2024 2024 (excluding the three months ended March 31, 2024) $ 24,711 2025 33,074 2026 31,972 2027 44,528 2028 28,216 Thereafter 39,611 Lease receivable $ 202,112 Lessee Arrangements The following table details the components of net lease cost for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Finance leases: Amortization of right-of-use assets $ 113 $ 357 Interest on lease liabilities 38 42 Operating lease cost 1,294 1,285 Short-term lease cost 21 89 Variable lease cost 215 255 Sublease income ( 3 ) ( 3 ) Net lease cost $ 1,678 $ 2,025 The following table details the cash payments included in the measurement of lease liabilities during the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Finance leases: Operating cash flows included in operating activities $ 38 $ 42 Financing cash flows included in payments under finance lease obligations 99 342 Operating leases: Operating cash flows (fixed payments) included in other operating activities, net 1,212 1,242 Operating cash flows (liability reduction) included in other operating activities, net 865 944 The following table details balance sheet information, as well as weighted-average lease terms and discount rates, related to leases at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Finance lease right-of-use assets, net of accumulated depreciation $ 3,638 $ 3,751 Finance lease liabilities 4,234 4,334 Operating lease right-of-use assets 36,659 38,142 Operating lease liabilities 40,185 41,584 Weighted-average lease term: Finance leases 8.09 years 8.34 years Operating leases 10.00 years 10.13 years Weighted-average discount rate: Finance leases 3.61 % 3.61 % Operating leases 3.64 % 3.64 % At March 31, 2024, future minimum rental commitments under finance and operating leases were as follows ($ in thousands): Finance Leases Operating Leases 2024 (excluding the three months ended March 31, 2024) $ 435 $ 3,718 2025 584 4,998 2026 589 4,846 2027 594 4,900 2028 599 4,749 Thereafter 2,086 25,452 Total minimum lease payments 4,887 48,663 Less imputed interest ( 653 ) ( 8,478 ) Lease liabilities $ 4,234 $ 40,185

Deposits

Deposits	3 Months Ended
	Mar. 31, 2024
Deposits [Abstract]
Deposits	Note 7 – Deposits At March 31, 2024 and December 31, 2023, deposits consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Noninterest-bearing demand $ 3,039,652 $ 3,197,620 Interest-bearing demand 5,226,089 4,947,626 Savings 3,750,392 4,047,853 Time 3,322,424 3,376,664 Total $ 15,338,557 $ 15,569,763

Securities Sold Under Repurchas

Securities Sold Under Repurchase Agreements	3 Months Ended
	Mar. 31, 2024
Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold Under Repurchase Agreements	Note 8 – Securities Sold Under Repurchase Agreements Trustmark utilizes securities sold under repurchase agreements as a source of borrowing in connection with overnight repurchase agreements offered to commercial deposit customers by using its unencumbered investment securities as collateral. Trustmark accounts for its securities sold under repurchase agreements as secured borrowings in accordance with FASB ASC Subtopic 860-30, “Transfers and Servicing – Secured Borrowing and Collateral.” Securities sold under repurchase agreements are stated at the amount of cash received in connection with the transaction. Trustmark monitors collateral levels on a continual basis and may be required to provide additional collateral based on the fair value of the underlying securities. Securities sold under repurchase agreements were secured by securities with a carrying amount of $ 59.4 million and $ 61.6 million at March 31, 2024 and December 31, 2023, respectively. Trustmark’s repurchase agreements are transacted under master repurchase agreements that give Trustmark, in the event of default by the counterparty, the right of offset with the same counterparty. At both March 31, 2024 and December 31, 2023 , all repurchase agreements were short-term and consisted primarily of sweep repurchase arrangements, under which excess deposits are “swept” into overnight repurchase agreements with Trustmark. The following table presents the securities sold under repurchase agreements by collateral pledged at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Mortgage-backed securities Residential mortgage pass-through securities Issued by FNMA and FHLMC $ 39,437 $ 28,600 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 285 526 Total securities sold under repurchase agreements $ 39,722 $ 29,126

Revenue from Contracts with Cus

Revenue from Contracts with Customers	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Note 9 – Revenue from Contracts with Customers Trustmark accounts for revenue from contracts with customers in accordance with FASB ASC Topic 606, “Revenue from Contracts with Customers,” which provides that revenue be recognized in a manner that depicts the transfer of goods or services to a customer in an amount that reflects the consideration Trustmark expects to be entitled to in exchange for those goods or services. Revenue from contracts with customers is recognized either over time in a manner that depicts Trustmark’s performance, or at a point in time when control of the goods or services are transferred to the customer. Trustmark’s noninterest income, excluding all of mortgage banking, net and securities gains (losses), net and portions of bank card and other fees and other income, are considered within the scope of FASB ASC Topic 606. Gains or losses on the sale of other real estate, which are included in Trustmark’s noninterest expense as other real estate expense, are also within the scope of FASB ASC Topic 606. Trustmark records a gain or loss from the sale of other real estate when control of the property transfers to the buyer. Trustmark records the gain or loss from the sale of other real estate in noninterest expense as other, net. Other real estate sales for the three months ended March 31, 2024 resulted in a net loss of $ 55 thousand compared to a net loss of $ 78 thousand for the three months ended March 31, 2023. The following table presents noninterest income disaggregated by reportable operating segment and revenue stream for the periods presented ($ in thousands): Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Topic 606 Not Topic (1) Total Topic 606 Not Topic (1) Total General Banking Segment Service charges on deposit accounts $ 10,936 $ — $ 10,936 $ 10,315 $ — $ 10,315 Bank card and other fees 7,192 200 7,392 7,643 149 7,792 Mortgage banking, net — 8,915 8,915 — 7,639 7,639 Wealth management 189 — 189 233 — 233 Other, net 3,348 ( 382 ) 2,966 2,988 ( 608 ) 2,380 Total noninterest income $ 21,665 $ 8,733 $ 30,398 $ 21,179 $ 7,180 $ 28,359 Wealth Management Segment Service charges on deposit accounts $ 22 $ — $ 22 $ 21 $ — $ 21 Bank card and other fees 36 — 36 11 — 11 Wealth management 8,763 — 8,763 8,547 — 8,547 Other, net 42 94 136 45 95 140 Total noninterest income $ 8,863 $ 94 $ 8,957 $ 8,624 $ 95 $ 8,719 Insurance Segment Insurance commissions $ 15,464 $ — $ 15,464 $ 14,305 $ — $ 14,305 Other, net 530 — 530 ( 6 ) — ( 6 ) Total noninterest income $ 15,994 $ — $ 15,994 $ 14,299 $ — $ 14,299 Consolidated Service charges on deposit accounts $ 10,958 $ — $ 10,958 $ 10,336 $ — $ 10,336 Bank card and other fees 7,228 200 7,428 7,654 149 7,803 Mortgage banking, net — 8,915 8,915 — 7,639 7,639 Insurance commissions 15,464 — 15,464 14,305 — 14,305 Wealth management 8,952 — 8,952 8,780 — 8,780 Other, net 3,920 ( 288 ) 3,632 3,027 ( 513 ) 2,514 Total noninterest income $ 46,522 $ 8,827 $ 55,349 $ 44,102 $ 7,275 $ 51,377 (1) Noninterest income not in scope for FASB ASC Topic 606 includes customer derivatives revenue and miscellaneous credit card fee income within bank card and other fees; mortgage banking, net; amortization of tax credits, accretion of the FDIC indemnification asset, cash surrender value on various life insurance policies, earnings on Trustmark’s non-qualified deferred compensation plans, other partnership investments and rental income within other, net; and security gains (losses), net.

Defined Benefit and Other Postr

Defined Benefit and Other Postretirement Benefits	3 Months Ended
	Mar. 31, 2024
Retirement Benefits [Abstract]
Defined Benefit and Other Postretirement Benefits	Note 10 – Defined Benefit and Other Postretirement Benefits Qualified Pension Plan Trustmark maintains a noncontributory tax-qualified defined benefit pension plan titled the Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions (the Continuing Plan) to satisfy commitments made by Trustmark to associates covered through plans obtained in acquisitions. The following table presents information regarding the net periodic benefit cost for the Continuing Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Service cost $ 10 $ 13 Interest cost 62 73 Expected return on plan assets ( 24 ) ( 26 ) Recognized net loss due to lump sum settlements — 25 Net periodic benefit cost $ 48 $ 85 For the plan year ending December 31, 2024, Trustmark’s minimum required contribution to the Continuing Plan is $ 132 thousand; however, Management and the Board of Directors of Trustmark will monitor the Continuing Plan throughout 2024 to determine any additional funding requirements by the plan’s measurement date, which is December 31. Supplemental Retirement Plans Trustmark maintains a nonqualified supplemental retirement plan covering key executive officers and senior officers as well as directors who have elected to defer fees. The plan provides for retirement and/or death benefits based on a participant’s covered salary or deferred fees. Although plan benefits may be paid from Trustmark’s general assets, Trustmark has purchased life insurance contracts on the participants covered under the plan, which may be used to fund future benefit payments under the plan. The annual measurement date for the plan is December 31. As a result of mergers prior to 2014, Trustmark became the administrator of nonqualified supplemental retirement plans, for which the plan benefits were frozen prior to the merger date. The following table presents information regarding the net periodic benefit cost for Trustmark’s nonqualified supplemental retirement plans for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Service cost $ 11 $ 17 Interest cost 477 520 Amortization of prior service cost 28 28 Recognized net actuarial loss 95 77 Net periodic benefit cost $ 611 $ 642

Stock and Incentive Compensatio

Stock and Incentive Compensation	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Stock and Incentive Compensation	Note 11 – Stock and Incentive Compensation Trustmark has granted restricted stock units subject to the provisions of the Stock and Incentive Compensation Plan (the Stock Plan). Current outstanding and future grants of restricted stock units are subject to the provisions of the Stock Plan, which is designed to provide flexibility to Trustmark regarding its ability to motivate, attract and retain the services of key associates and directors. The Stock Plan also allows Trustmark to grant nonqualified stock options, incentive stock options, stock appreciation rights, restricted stock, restricted stock units and performance units to key associates and directors. Restricted Stock Grants Performance Units Trustmark’s performance units vest over three years and are granted to Trustmark’s executive and senior management teams. Performance units granted vest based on performance goals of return on average tangible equity and total shareholder return. Performance units are valued utilizing a Monte Carlo simulation model to estimate fair value of the units at the grant date. The Monte Carlo simulation was performed by an independent valuation consultant and requires the use of subjective modeling assumptions. These units are recognized using the straight-line method over the requisite service period. These units provide for achievement units if performance measures exceed 100 %. The restricted stock agreement for these units provide for dividend privileges, but no voting rights. Time-Based Units Trustmark’s time-based units granted to Trustmark’s executive and senior management teams vest over three years . Trustmark’s time-based units granted to members of Trustmark’s Board of Directors vest over one year . Time-based units are valued utilizing the fair value of Trustmark’s stock at the grant date. These units are recognized on the straight-line method over the requisite service period. The restricted stock agreement for these units provide for dividend privileges, but no voting rights. The following table summarizes the Stock Plan activity for the period presented: Three Months Ended March 31, 2024 Performance Time-Vested Nonvested units, beginning of period 174,214 358,252 Granted 89,928 139,226 Released from restriction ( 54,973 ) ( 103,594 ) Forfeited — ( 2,334 ) Nonvested units, end of period 209,169 391,550 The following table presents information regarding compensation expense for units under the Stock Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Performance units $ 462 $ 278 Time-vested units 1,776 1,437 Total compensation expense $ 2,238 $ 1,715

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Note 12 – Contingencies Lending Related Trustmark makes commitments to extend credit and issues standby and commercial letters of credit (letters of credit) in the normal course of business in order to fulfill the financing needs of its customers. The carrying amount of commitments to extend credit and letters of credit approximates the fair value of such financial instruments. Commitments to extend credit are agreements to lend money to customers pursuant to certain specified conditions. Commitments generally have fixed expiration dates or other termination clauses. Because many of these commitments are expected to expire without being fully drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The exposure to credit loss in the event of nonperformance by the other party to the commitments to extend credit is represented by the contract amount of those instruments. Trustmark applies the same credit policies and standards as it does in the lending process when making these commitments. The collateral obtained is based upon the nature of the transaction and the assessed creditworthiness of the borrower. At March 31, 2024 and 2023 , Trustmark had unused commitments to extend credit of $ 4.792 billion and $ 5.424 billion, respectively. Letters of credit are conditional commitments issued by Trustmark to insure the performance of a customer to a third-party. A financial standby letter of credit irrevocably obligates Trustmark to pay a third-party beneficiary when a customer fails to repay an outstanding loan or debt instrument. A performance standby letter of credit irrevocably obligates Trustmark to pay a third-party beneficiary when a customer fails to perform some contractual, nonfinancial obligation. When issuing letters of credit, Trustmark uses the same policies regarding credit risk and collateral, which are followed in the lending process. At March 31, 2024 and 2023, Trustmark’s maximum exposure to credit loss in the event of nonperformance by the customer for letters of credit was $ 139.5 million and $ 137.3 million, respectively. These amounts consist primarily of commitments with maturities of less than three years , which have an immaterial carrying value. Trustmark holds collateral to support standby letters of credit when deemed necessary. As of March 31, 2024 and 2023 , the fair value of collateral held was $ 33.1 million and $ 31.3 million, respectively. ACL on Off-Balance Sheet Credit Exposures Trustmark maintains a separate ACL on off-balance sheet credit exposures, including unfunded loan commitments and letters of credit, which is included on the accompanying consolidated balance sheet as of March 31, 2024 and December 31, 2023. During the first quarter of 2024, Management decided to implement a performance trends qualitative factor for unfunded commitments. The same assumptions are applied in this calculation that the funded balances utilize with the addition of using the funding rates on the unfunded commitments. The performance trends qualitative factor reserve is then added to the other calculated reserve to get a total reserve for off-balance sheet credit exposures. Changes in the ACL on off-balance sheet credit exposures were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 34,057 $ 36,838 PCL, off-balance sheet credit exposures ( 192 ) ( 2,242 ) Balance at end of period $ 33,865 $ 34,596 Adjustments to the ACL on off-balance sheet credit exposures are recorded to PCL, off-balance sheet credit exposures. The decrease in the ACL on off-balance sheet credit exposures for the three months ended March 31, 2024 was primarily due to decrease in required reserves as a result of a decrease in unfunded commitments largely offset by an increase in required reserves as a result of implementing the performance trend qualitative reserve factor. The decrease in the ACL on off-balance sheet credit exposures for the three months ended March 31, 2023 was primarily due to decreases in the total reserve rate used in the calculation for off-balance sheet credit exposures coupled with decreases in unfunded balances for the construction, land development and other land and other construction loan segments. No credit loss estimate is reported for off-balance sheet credit exposures that are unconditionally cancellable by Trustmark or for undrawn amounts under such arrangements that may be drawn prior to the cancellation of the arrangement. Legal Proceedings TNB and its subsidiaries are parties to lawsuits and other claims that arise in the ordinary course of business. Some of the lawsuits assert claims related to the lending, collection, servicing, investment, trust and other business activities, and some of the lawsuits allege substantial claims for damages. In accordance with FASB ASC Subtopic 450-20, “Loss Contingencies,” TNB will establish an accrued liability for any litigation matter if and when such matter presents loss contingencies that are both probable and reasonably estimable. At the present time, TNB believes, based on its evaluation and the advice of legal counsel, that a loss in any currently pending legal proceeding is not probable and a reasonable estimate cannot reasonably be made.

Earnings Per Share (EPS)

Earnings Per Share (EPS)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Earnings Per Share (EPS)	Note 13 – Earnings Per Share (EPS) The following table reflects weighted-average shares used to calculate basic and diluted EPS for the periods presented (in thousands): Three Months Ended March 31, 2024 2023 Basic shares 61,128 61,011 Dilutive shares 220 182 Diluted shares 61,348 61,193 Weighted-average antidilutive stock awards are excluded in determining diluted EPS. There were no weighted-average antidilutive stock awards for the three months ended March 31, 2024 and 2023.

Statements of Cash Flows

Statements of Cash Flows	3 Months Ended
	Mar. 31, 2024
Supplemental Cash Flow Information [Abstract]
Statements of Cash Flows	Note 14 – Statements of Cash Flows The following table reflects specific transaction amounts for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Interest expense paid on deposits and borrowings $ 98,327 $ 54,823 Noncash transfers from loans to other real estate 2,228 300

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2024
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Note 15 – Shareholders’ Equity Regulatory Capital Trustmark and TNB are subject to minimum risk-based capital and leverage capital requirements, as described in the section captioned “Capital Adequacy” included in Part I. Item 1. – Business of Trustmark’s 2023 Annual Report, which are administered by the federal bank regulatory agencies. These capital requirements, as defined by federal regulations, involve quantitative and qualitative measures of assets, liabilities and certain off-balance sheet instruments. Trustmark’s and TNB’s minimum risk-based capital requirements include a capital conservation buffer of 2.50 %. Accumulated other comprehensive income (loss), net of tax, is not included in computing regulatory capital. Trustmark elected the five-year phase-in transition period (through December 31, 2024) related to adopting FASB ASU 2016-13 for regulatory capital purposes. Failure to meet minimum capital requirements can result in certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the financial statements of Trustmark and TNB and limit Trustmark’s and TNB’s ability to pay dividends. As of March 31, 2024, Trustmark and TNB exceeded all applicable minimum capital standards. In addition, Trustmark and TNB met applicable regulatory guidelines to be considered well-capitalized at March 31, 2024. To be categorized in this manner, Trustmark and TNB maintained, as applicable, minimum common equity Tier 1 risk-based capital, Tier 1 risk-based capital, total risk-based capital and Tier 1 leverage ratios as set forth in the accompanying table, and were not subject to any written agreement, order or capital directive, or prompt corrective action directive issued by their primary federal regulators to meet and maintain a specific capital level for any capital measures. There are no significant conditions or events that have occurred since March 31, 2024, which Management believes have affected Trustmark’s or TNB’s present classification. The following table provides Trustmark’s and TNB’s actual regulatory capital amounts and ratios under regulatory capital standards in effect at March 31, 2024 and December 31, 2023 ($ in thousands): Actual Regulatory Capital Minimum To Be Well Amount Ratio Requirement Capitalized At March 31, 2024: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,543,460 10.12 % 7.00 % n/a Trustmark National Bank 1,620,495 10.62 % 7.00 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,603,460 10.51 % 8.50 % n/a Trustmark National Bank 1,620,495 10.62 % 8.50 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,895,697 12.42 % 10.50 % n/a Trustmark National Bank 1,789,195 11.73 % 10.50 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,603,460 8.76 % 4.00 % n/a Trustmark National Bank 1,620,495 8.87 % 4.00 % 5.00 % At December 31, 2023: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,521,665 10.04 % 7.00 % n/a Trustmark National Bank 1,602,327 10.58 % 7.00 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,581,665 10.44 % 8.50 % n/a Trustmark National Bank 1,602,327 10.58 % 8.50 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,862,246 12.29 % 10.50 % n/a Trustmark National Bank 1,759,426 11.61 % 10.50 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,581,665 8.62 % 4.00 % n/a Trustmark National Bank 1,602,327 8.75 % 4.00 % 5.00 % Stock Repurchase Program On December 6, 2022, Trustmark’s Board of Directors authorized a stock repurchase program effective January 1, 2023, under which $ 50.0 million of Trustmark’s outstanding shares could be acquired through December 31, 2023. No shares were repurchased under this stock repurchase program. On December 5, 2023, Trustmark’s Board of Directors authorized a stock repurchase program effective January 1, 2024, under which $ 50.0 million of Trustmark’s outstanding shares may be acquired through December 31, 2024. The repurchase program, which is subject to market conditions and management discretion, will be implemented through open market repurchases or privately negotiated transactions. No shares have been repurchased under this stock repurchase program. Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) The following table presents the net change in the components of accumulated other comprehensive income (loss) and the related tax effects allocated to each component for the periods presented ($ in thousands). The amortization of prior service cost, recognized net loss due to lump sum settlements and change in net actuarial loss are included in the computation of net periodic benefit cost (see Note 10 – Defined Benefit and Other Postretirement Benefits for additional details). Reclassification adjustments related to pension and other postretirement benefit plans are included in salaries and employee benefits and other expense in the accompanying consolidated statements of income. Reclassification adjustments related to the cash flow hedge derivatives are included in interest and fees on LHFS and LHFI in the accompanying consolidated statements of income. Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Before Tax Tax (Expense) Net of Tax Before Tax Tax (Expense) Net of Tax Securities available for sale and transferred securities: Net unrealized holding gains (losses) arising $ ( 2,552 ) $ 638 $ ( 1,914 ) $ 30,534 $ ( 7,404 ) $ 23,130 Change in net unrealized holding loss on 3,661 ( 915 ) 2,746 3,859 ( 965 ) 2,894 Total securities available for sale 1,109 ( 277 ) 832 34,393 ( 8,369 ) 26,024 Pension and other postretirement benefit plans: Reclassification adjustments for changes Net change in prior service costs 28 ( 7 ) 21 28 ( 7 ) 21 Recognized net loss due to lump sum — — — 25 ( 6 ) 19 Change in net actuarial loss 95 ( 24 ) 71 77 ( 19 ) 58 Total pension and other postretirement 123 ( 31 ) 92 130 ( 32 ) 98 Cash flow hedge derivatives: Change in accumulated gain (loss) on effective ( 15,960 ) 3,990 ( 11,970 ) 6,269 ( 1,567 ) 4,702 Reclassification adjustment for (gain) loss realized 4,820 ( 1,205 ) 3,615 2,931 ( 733 ) 2,198 Total cash flow hedge derivatives ( 11,140 ) 2,785 ( 8,355 ) 9,200 ( 2,300 ) 6,900 Total other comprehensive income (loss) $ ( 9,908 ) $ 2,477 $ ( 7,431 ) $ 43,723 $ ( 10,701 ) $ 33,022 The following table presents the changes in the balances of each component of accumulated other comprehensive income (loss) for the periods presented ($ in thousands). All amounts are presented net of tax. Securities for Sale Defined Cash Flow Total Balance at January 1, 2024 $ ( 204,670 ) $ ( 6,075 ) $ ( 8,978 ) $ ( 219,723 ) Other comprehensive income (loss) before reclassification 832 — ( 11,970 ) ( 11,138 ) Amounts reclassified from accumulated other — 92 3,615 3,707 Net other comprehensive income (loss) 832 92 ( 8,355 ) ( 7,431 ) Balance at March 31, 2024 $ ( 203,838 ) $ ( 5,983 ) $ ( 17,333 ) $ ( 227,154 ) Balance at January 1, 2023 $ ( 254,442 ) $ ( 5,792 ) $ ( 15,169 ) $ ( 275,403 ) Other comprehensive income (loss) before reclassification 26,024 — 4,702 30,726 Amounts reclassified from accumulated other — 98 2,198 2,296 Net other comprehensive income (loss) 26,024 98 6,900 33,022 Balance at March 31, 2023 $ ( 228,418 ) $ ( 5,694 ) $ ( 8,269 ) $ ( 242,381 )

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value	Note 16 – Fair Value Financial Instruments Measured at Fair Value The methodologies Trustmark uses in determining the fair values are based primarily on the use of independent, market-based data to reflect a value that would be reasonably expected upon exchange of the position in an orderly transaction between market participants at the measurement date. The predominant portion of assets that are stated at fair value are of a nature that can be valued using prices or inputs that are readily observable through a variety of independent data providers. The providers selected by Trustmark for fair valuation data are widely recognized and accepted vendors whose evaluations support the pricing functions of financial institutions, investment and mutual funds, and portfolio managers. Trustmark has documented and evaluated the pricing methodologies used by the vendors and maintains internal processes that regularly test valuations for anomalies. Trustmark utilizes an independent pricing service to advise it on the carrying value of the securities available for sale portfolio. As part of Trustmark’s procedures, the price provided from the service is evaluated for reasonableness given market changes. When a questionable price exists, Trustmark investigates further to determine if the price is valid. If needed, other market participants may be utilized to determine the correct fair value. Trustmark has also reviewed and confirmed its determinations in thorough discussions with the pricing source regarding their methods of price discovery. Mortgage loan commitments are valued based on the securities prices of similar collateral, term, rate and delivery for which the loan is eligible to deliver in place of the particular security. Trustmark acquires a broad array of mortgage security prices that are supplied by a market data vendor, which in turn accumulates prices from a broad list of securities dealers. Prices are processed through a mortgage pipeline management system that accumulates and segregates all loan commitment and forward-sale transactions according to the similarity of various characteristics (maturity, term, rate, and collateral). Prices are matched to those positions that are deemed to be an eligible substitute or offset ( i.e ., “deliverable”) for a corresponding security observed in the marketplace. Trustmark estimates fair value of the MSR through the use of prevailing market participant assumptions and market participant valuation processes. This valuation is periodically tested and validated against other third-party firm valuations. Trustmark obtains the fair value of interest rate swaps from a third-party pricing service that uses an industry standard discounted cash flow methodology. In addition, credit valuation adjustments are incorporated in the fair values to account for potential nonperformance risk. In adjusting the fair value of its interest rate swap contracts for the effect of nonperformance risk, Trustmark has considered any applicable credit enhancements such as collateral postings, thresholds, mutual puts, and guarantees. In conjunction with the FASB’s fair value measurement guidance, Trustmark made an accounting policy election to measure the credit risk of these derivative financial instruments, which are subject to master netting agreements, on a net basis by counterparty portfolio. Trustmark has determined that the majority of the inputs used to value its interest rate swaps offered to qualified commercial borrowers fall within Level 2 of the fair value hierarchy, while the credit valuation adjustments associated with these derivatives utilize Level 3 inputs, such as estimates of current credit spreads. Trustmark has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its interest rate swaps and has determined that the credit valuation adjustment is not significant to the overall valuation of these derivatives. As a result, Trustmark classifies its interest rate swap valuations in Level 2 of the fair value hierarchy. Trustmark also utilizes exchange-traded derivative instruments such as Treasury note futures contracts and option contracts to achieve a fair value return that offsets the changes in fair value of the MSR attributable to interest rates. Fair values of these derivative instruments are determined from quoted prices in active markets for identical assets therefore allowing them to be classified within Level 1 of the fair value hierarchy. In addition, Trustmark utilizes derivative instruments such as interest rate lock commitments in its mortgage banking area which lack observable inputs for valuation purposes resulting in their inclusion in Level 3 of the fair value hierarchy. At this time, Trustmark presents no fair values that are derived through internal modeling. Should positions requiring fair valuation arise that are not relevant to existing methodologies, Trustmark will make every reasonable effort to obtain market participant assumptions, or independent evaluation. Financial Assets and Liabilities The following tables summarize financial assets and financial liabilities measured at fair value on a recurring basis at March 31, 2024 and December 31, 2023, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value ($ in thousands). There were no transfers between fair value levels for the three months ended March 31, 2024 and the year ended December 31, 2023. March 31, 2024 Total Level 1 Level 2 Level 3 U.S. Treasury securities $ 372,424 $ 372,424 $ — $ — U.S. Government agency obligations 5,594 — 5,594 — Mortgage-backed securities 1,324,281 — 1,324,281 — Securities available for sale 1,702,299 372,424 1,329,875 — LHFS 172,937 — 172,937 — MSR 138,044 — — 138,044 Other assets - derivatives 16,953 1,152 14,644 1,157 Other liabilities - derivatives 40,803 102 40,701 — December 31, 2023 Total Level 1 Level 2 Level 3 U.S. Treasury securities $ 372,368 $ 372,368 $ — $ — U.S. Government agency obligations 5,792 — 5,792 — Mortgage-backed securities 1,384,718 — 1,384,718 — Securities available for sale 1,762,878 372,368 1,390,510 — LHFS 184,812 — 184,812 — MSR 131,870 — — 131,870 Other assets - derivatives 23,316 7,685 14,786 845 Other liabilities - derivatives 35,600 21 35,579 — The changes in Level 3 assets measured at fair value on a recurring basis for the three months ended March 31, 2024 and 2023 are summarized as follows ($ in thousands): MSR Other Assets - Balance, January 1, 2024 $ 131,870 $ 845 Total net (loss) gain included in Mortgage banking, net (1) 3,197 1,047 Additions 2,977 — Sales — ( 735 ) Balance, March 31, 2024 $ 138,044 $ 1,157 The amount of total gains (losses) for the period included in earnings $ 5,123 $ 927 Balance, January 1, 2023 $ 129,677 $ 157 Total net (loss) gain included in Mortgage banking, net (1) ( 5,117 ) 1,288 Additions 2,646 — Sales — ( 105 ) Balance, March 31, 2023 $ 127,206 $ 1,340 The amount of total gains (losses) for the period included in $ ( 3,972 ) $ 531 (1) Total net (loss) gain included in Mortgage banking, net relating to the MSR includes changes in fair value due to market changes and due to run-off. Trustmark may be required, from time to time, to measure certain assets at fair value on a nonrecurring basis in accordance with GAAP. Assets at March 31, 2024, which have been measured at fair value on a nonrecurring basis, include collateral-dependent LHFI. A loan is collateral dependent when the borrower is experiencing financial difficulty and repayment of the loan is expected to be provided substantially through the sale of the collateral. The expected credit loss for collateral-dependent loans is measured as the difference between the amortized cost basis of the loan and the fair value of the collateral, adjusted for the estimated cost to sell. Fair value estimates for collateral-dependent loans are derived from appraised values based on the current market value or as is value of the collateral, normally from recently received and reviewed appraisals. Current appraisals are ordered on an annual basis based on the inspection date or more often if market conditions necessitate. Appraisals are obtained from state-certified appraisers and are based on certain assumptions, which may include construction or development status and the highest and best use of the property. These appraisals are reviewed by Trustmark’s Appraisal Review Department to ensure they are acceptable, and values are adjusted down for costs associated with asset disposal. At March 31, 2024 , Trustmark had outstanding balances of $ 42.9 million with a related ACL of $ 12.6 million in collateral-dependent LHFI, compared to outstanding balances of $ 49.1 million with a related ACL of $ 12.4 million in collateral-dependent LHFI at December 31, 2023. The collateral-dependent LHFI are classified as Level 3 in the fair value hierarchy. Nonfinancial Assets and Liabilities Certain nonfinancial assets measured at fair value on a nonrecurring basis include foreclosed assets (upon initial recognition or subsequent impairment), nonfinancial assets and nonfinancial liabilities measured at fair value in the second step of a goodwill impairment test, and intangible assets and other nonfinancial long-lived assets measured at fair value for impairment assessment. Other real estate includes assets that have been acquired in satisfaction of debt through foreclosure and is recorded at the fair value less cost to sell (estimated fair value) at the time of foreclosure. Fair value is based on independent appraisals and other relevant factors. In the determination of fair value subsequent to foreclosure, Management also considers other factors or recent developments, such as changes in market conditions from the time of valuation and anticipated sales values considering plans for disposition, which could result in an adjustment to lower the collateral value estimates indicated in the appraisals. Periodic revaluations are classified as Level 3 in the fair value hierarchy since assumptions are used that may not be observable in the market. Foreclosed assets of $ 194 thousand were remeasured during the first three months of 2024 , requiring write-downs of $ 34 thousand to reach their current fair values compared to $ 430 thousand of foreclosed assets that were remeasured during the first three months of 2023 , requiring write-downs of $ 20 thousand. Fair Value of Financial Instruments FASB ASC Topic 825, “Financial Instruments,” requires disclosure of the fair value of financial assets and financial liabilities, including those financial assets and financial liabilities that are not measured and reported at fair value on a recurring basis or non-recurring basis. The carrying amounts and estimated fair values of financial instruments at March 31, 2024 and December 31, 2023, are as follows ($ in thousands): March 31, 2024 December 31, 2023 Carrying Estimated Carrying Estimated Financial Assets: Level 2 Inputs: Cash and short-term investments $ 606,261 $ 606,261 $ 975,543 $ 975,543 Securities held to maturity 1,415,025 1,333,014 1,426,279 1,355,504 Level 3 Inputs: Net LHFI 12,914,945 12,809,237 12,811,157 12,762,505 Financial Liabilities: Level 2 Inputs: Deposits 15,338,557 15,320,852 15,569,763 15,553,417 Federal funds purchased and securities sold under 393,215 393,215 405,745 405,745 Other borrowings 482,027 482,024 483,230 483,226 Subordinated notes 123,537 110,625 123,482 108,125 Junior subordinated debt securities 61,856 47,011 61,856 48,856 Fair Value Option Trustmark has elected to account for its mortgage LHFS under the fair value option, with interest income on these mortgage LHFS reported in interest and fees on LHFS and LHFI. The fair value of the mortgage LHFS is determined using quoted prices for a similar asset, adjusted for specific attributes of that loan. The mortgage LHFS are actively managed and monitored and certain market risks of the loans may be mitigated through the use of derivatives. These derivative instruments are carried at fair value with changes in fair value recorded as noninterest income in mortgage banking, net. The changes in the fair value of LHFS are largely offset by changes in the fair value of the derivative instruments. For the three months ended March 31, 2024 , a net loss of $ 1.5 million was recorded as noninterest income in mortgage banking, net for changes in the fair value of LHFS accounted for under the fair value option, compared to a net gain of $ 944 thousand for the three months ended March 31, 2023. Interest and fees on LHFS and LHFI for the three months ended March 31, 2024 included $ 1.7 million of interest earned on LHFS accounted for under the fair value option, compared to $ 1.5 million for the three months ended March 31, 2023 . Election of the fair value option allows Trustmark to reduce the accounting volatility that would otherwise result from the asymmetry created by accounting for the financial instruments at the lower of cost or fair value and the derivatives at fair value. The fair value option election does not apply to GNMA optional repurchase loans which do not meet the requirements under FASB ASC Topic 825 to be accounted for under the fair value option. GNMA optional repurchase loans totaled $ 77.7 million and $ 78.8 million at March 31, 2024 and December 31, 2023, respectively, and are included in LHFS on the accompanying consolidated balance sheets. For additional information regarding GNMA optional repurchase loans, please see the section captioned “Past Due LHFS” included in Note 3 – LHFI and ACL, LHFI. The following table provides information about the fair value and the contractual principal outstanding of LHFS accounted for under the fair value option at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Fair value of LHFS $ 95,197 $ 105,974 LHFS contractual principal outstanding 93,598 102,994 Fair value less unpaid principal $ 1,599 $ 2,980

Derivative Financial Instrument

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Note 17 – Derivative Financial Instruments Derivatives Designated as Hedging Instruments During 2022, Trustmark initiated a cash flow hedging program. Trustmark's objectives in initiating this hedging program were to add stability to interest income and to manage its exposure to interest rate movements. Interest rate swaps designated as cash flow hedges involve the receipt of fixed-rate amounts from a counterparty in exchange for Trustmark making variable-rate payments over the life of the agreements without exchange of the underlying notional amount. Interest rate floor spreads designated as cash flow hedges involve the receipt of variable-rate amounts if interest rates fall below the purchased floor strike rate on the contract and payments of variable-rate amounts if interest rates fall below the sold floor strike rate on the contract. Trustmark uses such derivatives to hedge the variable cash flows associated with existing and anticipated variable-rate loan assets. At March 31, 2024 , the aggregate notional value of Trustmark's interest rate swaps and floor spreads designated as cash flow hedges totaled $ 1.225 billion compared to $ 1.125 billion at December 31, 2023. Trustmark records any gains or losses on these cash flow hedges in accumulated other comprehensive income (loss). Gains and losses on derivatives representing hedge components excluded from the assessment of effectiveness are recognized over the life of the hedge on a systematic and rational basis, as documented at hedge inception in accordance with Trustmark’s accounting policy election. The earnings recognition of excluded components totaled $ 85 thousand and $ 9 thousand of amortization expense for the three months ended March 31, 2024 and 2023, respectively, and are included in interest and fees on LHFS and LHFI. As interest payments are received on Trustmark's variable-rate a ssets, amounts reported in accumulated other comprehensive income (loss) are reclassified into interest and fees on LHFS and LHFI in the accompanying consolidated statements of income during the same period. During the next twelve months, Trustmark estimates that $ 15.5 million will be reclassified as a reduction to interest and fees on LHFS and LHFI. This amount could differ due to changes in interest rates, hedge de-designations or the addition of other hedges. Derivatives not Designated as Hedging Instruments Trustmark utilizes a portfolio of exchange-traded derivative instruments, such as Treasury note futures contracts and option contracts, to achieve a fair value return that economically hedges changes in the fair value of the MSR attributable to interest rates. These transactions are considered freestanding derivatives that do not otherwise qualify for hedge accounting. The total notional amount of these derivative instruments was $ 301.0 million at March 31, 2024 compared to $ 285.0 million at December 31, 2023. Changes in the fair value of these exchange-traded derivative instruments are recorded as noninterest income in mortgage banking, net and are offset by changes in the fair value of the MSR. The impact of this strategy resulted in a net negative ineffectiveness of $ 1.1 million and $ 1.8 million for the three months ended March 31, 2024 and 2023, respectively. As part of Trustmark’s risk management strategy in the mortgage banking area, derivative instruments such as forward sales contracts are utilized. Trustmark’s obligations under forward sales contracts consist of commitments to deliver mortgage loans, originated and/or purchased, in the secondary market at a future date. Changes in the fair value of these derivative instruments are recorded as noninterest income in mortgage banking, net and are offset by changes in the fair value of LHFS. Trustmark’s off-balance sheet obligations under these derivative instruments totaled $ 128.5 million at March 31, 2024 , with a negative valuation adjustment of $ 208 thousand, compared to $ 109.5 million, with a negative valuation adjustment of $ 994 thousand, at December 31, 2023. Trustmark also utilizes derivative instruments such as interest rate lock commitments in its mortgage banking area. Interest rate lock commitments are residential mortgage loan commitments with customers, which guarantee a specified interest rate for a specified time period. Changes in the fair value of these derivative instruments are recorded as noninterest income in mortgage banking, net and are offset by the changes in the fair value of forward sales contracts. Trustmark’s off-balance sheet obligations under these derivative instruments totaled $ 88.5 million at March 31, 2024 , with a positive valuation adjustment of $ 1.2 million, compared to $ 61.9 million, with a positive valuation adjustment of $ 845 thousand, at December 31, 2023. Trustmark offers certain derivatives products directly to qualified commercial lending clients seeking to manage their interest rate risk. Trustmark economically hedges interest rate swap transactions executed with commercial lending clients by entering into offsetting interest rate swap transactions with institutional derivatives market participants. Derivatives transactions executed as part of this program are not designated as qualifying hedging relationships and are, therefore, carried at fair value with the change in fair value recorded as noninterest income in bank card and other fees. Because these derivatives have mirror-image contractual terms, in addition to collateral provisions which mitigate the impact of non-performance risk, the changes in fair value are expected to substantially offset. The offsetting interest rate swap transactions are either cleared through the Chicago Mercantile Exchange for clearable transactions or booked directly with institutional derivatives market participants for non-clearable transactions. The Chicago Mercantile Exchange rules legally characterize variation margin collateral payments made or received for centrally cleared interest rate swaps as settlements rather than collateral. As a result, centrally cleared interest rate swaps included in other assets and other liabilities are presented on a net basis in the accompanying consolidated balance sheets. At March 31, 2024 , Trustmark had interest rate swaps with an aggregate notional amount of $ 1.470 billion related to this program, compared to $ 1.500 billion at December 31, 2023. Credit-risk-related Contingent Features Trustmark has agreements with its financial institution counterparties that contain provisions where if Trustmark defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then Trustmark could also be declared in default on its derivatives obligations. At March 31, 2024 , there was no termination value of i nterest rate swaps in a liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements compared to $ 1.4 million at December 31, 2023. At March 31, 2024 and December 31, 2023 , Trustmark had posted collateral of $ 40 thousand and $ 2.0 million, respectively, against its obligations because of negotiated thresholds and minimum transfer amounts under these agreements. If Trustmark had breached any of these triggering provisions at March 31, 2024, it could have been required to settle its obligations under the agreements at the termination value. Credit risk participation agreements arise when Trustmark contracts with other financial institutions, as a guarantor or beneficiary, to share credit risk associated with certain interest rate swaps. These agreements provide for reimbursement of losses resulting from a third-party default on the underlying swap. At March 31, 2024 , Trustmark had entered into seven risk p articipation agreements as a beneficiary with aggregate notional amounts of $ 44.9 million compared to six risk participation agreements as a beneficiary with an aggregate notional amount of $ 40.1 million at December 31, 2023. At March 31, 2024 and December 31, 2023 , Trustmark had entered into thirty-five risk participation agreements as a guarantor with aggregate notional amounts of $ 304.1 million and $ 304.7 million, respectively. The aggregate fair values of these risk participation agreements were immaterial at both March 31, 2024 and December 31, 2023. Tabular Disclosures The following tables disclose the fair value of derivative instruments in Trustmark’s consolidated balance sheets at March 31, 2024 and December 31, 2023 as well as the effect of these derivative instruments on Trustmark’s results of operations for the periods presented ($ in thousands): March 31, 2024 December 31, 2023 Derivatives in hedging relationships: Interest rate contracts: Interest rate swaps included in other assets (1) $ 49 $ 1,182 Interest rate floors included in other assets 1,591 1,689 Interest rate swaps included in other liabilities (1) 2,442 267 Derivatives not designated as hedging instruments: Interest rate contracts: Exchange traded purchased options included in other assets $ 17 $ 180 OTC written options (rate locks) included in other assets 1,157 845 Futures contracts included in other assets 1,135 7,505 Interest rate swaps included in other assets (1) 13,000 11,910 Credit risk participation agreements included in other assets 4 5 Forward contracts included in other liabilities 208 994 Exchange traded written options included in other liabilities 102 21 Interest rate swaps included in other liabilities (1) 38,019 34,255 Credit risk participation agreements included in other liabilities 32 63 (1) In accordance with GAAP, the variation margin collateral payments made or received for interest rate swaps that are centrally cleared are legally characterized as settled. As a result, the centrally cleared interest rate swaps included in other assets and other liabilities are presented on a net basis in the accompanying consolidated balance sheets. Three Months Ended March 31, 2024 2023 Derivatives in hedging relationships: Amount of gain (loss) reclassified from accumulated other $ ( 4,820 ) $ ( 2,931 ) Derivatives not designated as hedging instruments: Amount of gain (loss) recognized in mortgage banking, net $ ( 5,126 ) $ 2,455 Amount of gain (loss) recognized in bank card and other fees ( 56 ) ( 10 ) The following table discloses the amount included in other comprehensive income (loss), net of tax, for derivative instruments designated as cash flow hedges for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Derivatives in cash flow hedging relationship Amount of gain (loss) recognized in other comprehensive $ ( 11,970 ) $ 4,702 Trustmark’s interest rate swap derivative instruments are subject to master netting agreements, and therefore, eligible for offsetting in the consolidated balance sheets. Trustmark has elected to not offset any derivative instruments in its consolidated balance sheets. Information about financial instruments that are eligible for offset in the consolidated balance sheets as of March 31, 2024 and December 31, 2023 is presented in the following tables ($ in thousands): Offsetting of Derivative Assets As of March 31, 2024 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 14,640 $ — $ 14,640 $ ( 3,746 ) $ ( 2,500 ) $ 8,394 Offsetting of Derivative Liabilities As of March 31, 2024 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 40,461 $ — $ 40,461 $ ( 3,746 ) $ ( 40 ) $ 36,675 Offsetting of Derivative Assets As of December 31, 2023 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 14,781 $ — $ 14,781 $ ( 4,339 ) $ — $ 10,442 Offsetting of Derivative Liabilities As of December 31, 2023 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 34,522 $ — $ 34,522 $ ( 4,339 ) $ ( 2,040 ) $ 28,143

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
Segment Information	Note 18 – Segment Information Trustmark’s management reporting structure includes three segments: General Banking, Wealth Management and Insurance. For a complete overview of Trustmark’s operating segments, see Note 20 – Segment Information included in Part II. Item 8. – Financial Statements and Supplementary Data, of Trustmark’s 2023 Annual Report. The accounting policies of each reportable segment are the same as those of Trustmark except for its internal allocations. Noninterest expenses for back-office operations support are allocated to segments based on estimated uses of those services. Trustmark measures the net interest income of its business segments with a process that assigns cost of funds or earnings credit on a matched-term basis. This process, called “funds transfer pricing”, charges an appropriate cost of funds to assets held by a business unit, or credits the business unit for potential earnings for carrying liabilities. The net of these charges and credits flows through to the General Banking Segment, which contains the management team responsible for determining TNB’s funding and interest rate risk strategies. The following table discloses financial information by reportable segment for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 General Banking Net interest income $ 131,517 $ 136,159 Provision for credit losses 7,348 934 Noninterest income 30,398 28,359 Noninterest expense 111,708 109,590 Income before income taxes 42,859 53,994 Income taxes 6,309 7,924 General banking net income $ 36,550 $ 46,070 Selected Financial Information Total assets $ 18,093,454 $ 18,578,910 Depreciation and amortization $ 8,367 $ 7,443 Wealth Management Net interest income $ 1,316 $ 1,439 Provision for credit losses 168 68 Noninterest income 8,957 8,719 Noninterest expense 7,991 8,034 Income before income taxes 2,114 2,056 Income taxes 523 513 Wealth management net income $ 1,591 $ 1,543 Selected Financial Information Total assets $ 178,165 $ 207,414 Depreciation and amortization $ 62 $ 69 Insurance Net interest income $ ( 3 ) $ ( 3 ) Noninterest income 15,994 14,299 Noninterest expense 11,447 10,703 Income before income taxes 4,544 3,593 Income taxes 1,150 906 Insurance net income $ 3,394 $ 2,687 Selected Financial Information Total assets $ 104,993 $ 90,854 Depreciation and amortization $ 134 $ 154 Consolidated Net interest income $ 132,830 $ 137,595 Provision for credit losses 7,516 1,002 Noninterest income 55,349 51,377 Noninterest expense 131,146 128,327 Income before income taxes 49,517 59,643 Income taxes 7,982 9,343 Consolidated net income $ 41,535 $ 50,300 Selected Financial Information Total assets $ 18,376,612 $ 18,877,178 Depreciation and amortization $ 8,563 $ 7,666

Accounting Policies Recently Ad

Accounting Policies Recently Adopted and Pending Accounting Pronouncements	3 Months Ended
	Mar. 31, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
Accounting Policies Recently Adopted and Pending Accounting Pronouncements	Note 19 – Accounting Policies Recently Adopted and Pending Accounting Pronouncements Accounting Policies Recently Adopted Except for the changes detailed below, Trustmark has consistently applied its accounting policies to all periods presented in the accompanying consolidated financial statements. ASU 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” Issued in November 2023, ASU 2023-07 is intended to improve disclosures about a public entity’s reportable segments and address requests from investors and other allocators of capital for additional, more detailed information about a reportable segment’s expenses. The amendments of ASU 2023-07 require a public entity to disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker (CODM) and included within each reported measure of segment profit or loss, and an amount for other segment items by reportable segment and a description of its composition. The other segment items category is the difference between segment revenue less the significant expenses disclosed and each reported measure of segment profit or loss. ASU 2023-07 also requires a public entity to provide all annual disclosures about a reportable segment’s profit or loss and assets currently required under FASB ASC Topic 280 in interim periods. The amendments of ASU 2023-07 clarify that if the CODM uses more than one measure of a segment's profit or loss in assessing segment performance and deciding how to allocate resources, a public entity may report one or more of those additional measures of segment profit. However, at least one of the reported segment profit or loss measures (or the single reported measure if only one is disclosed) should be the measure that is most consistent with the measurement principles used in measuring the corresponding amounts in the public entity's consolidated financial statements. ASU 2023-07 requires a public entity to disclose the title and position of the CODM, together with an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. In addition, ASU 2023-07 requires that a public entity with a single reportable segment provide all the disclosures required by the amendments of ASU 2023-07 and all existing segment disclosures in FASB ASC Topic 280. The amendments of ASU 2023-07 are effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments in ASU 2023-07 should be applied retrospectively to all periods presented on the financial statements. Upon implementation, the segment expense categories and amounts disclosed in the prior periods should be based on the significant segment expense categories identified and disclosed in the period of adoption. Trustmark has adopted the amendments of ASU 2023-07 related to annual disclosure requirements effective January 1, 2024 , and will present any newly required annual disclosures in its Annual Report of Form 10-K for the year ending December 31, 2024. Trustmark intends to adopt the amendments of ASU 2023-07 related to interim disclosure requirements effective January 1, 2025, and will present any newly required interim disclosures beginning with its Quarterly Report on Form 10-Q for the period ending March 31, 2025. Adoption of ASU 2023-07 is no t expected to have a material impact to Trustmark’s consolidated financial statements or results of operations. Pending Accounting Pronouncements ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” Issued in December 2023, ASU 2023-09 is intended to improve the disclosures for income taxes to address requests from investors, lenders, creditors and other allocators of capital (collectively, "investors") that use the financial statements to make capital allocation decisions. During the FASB's 2021 agenda consultation process and other stakeholder outreach, investors highlighted that the current system of income tax disclosures does not provide enough information to understand the tax provision for an entity that operates in multiple jurisdictions. Investors currently rely on the rate reconciliation table and other disclosures, including total income taxes paid in the statement of cash flows, to evaluate income tax risks and opportunities. The amendments in ASU 2023-09 will require consistent categories and greater disaggregation of information in the rate reconciliation disclosure as well as disclosure of income taxes paid disaggregated by jurisdiction. The amendments of ASU 2023-09 are effective for annual periods beginning after December 15, 2024, and early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. Trustmark intends to adopt the amendments of ASU 2023-09 effective January 1, 2025 , and will include the required disclosures in its Annual Report on Form 10-K for the year ending December 31, 2025. Trustmark is currently evaluating the changes to disclosures required by ASU 2023-09; however, adoption of ASU 2023-09 is no t expected to have a material impact to Trustmark’s consolidated financial statements or results of operations.

Accounting Policies Recently _2

Accounting Policies Recently Adopted and Pending Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Securities Available for Sale	Securities Available for Sale Quarterly, Trustmark evaluates if any security has a fair value less than its amortized cost. Once these securities are identified, in order to determine whether a decline in fair value resulted from a credit loss or other factors, Trustmark performs further analysis. If Trustmark determines that a credit loss exists, the credit portion of the allowance is measured using a discounted cash flow (DCF) analysis using the effective interest rate as of the security’s purchase date. The amount of credit loss recorded by Trustmark is limited to the amount by which the amortized cost exceeds the fair value. The DCF analysis utilizes contractual maturities, as well as third-party credit ratings and cumulative default rates published annually by Moody’s Investor Service (Moody’s). At both March 31, 2024 and December 31, 2023 , the results of the analysis did not identify any securities that warranted DCF analysis, and no credit loss was recognized on any of the securities available for sale. Accrued interest receivable is excluded from the estimate of credit losses for securities available for sale. At both March 31, 2024 and December 31, 2023 , accrued interest receivable totaled $ 3.7 million for securities available for sale and was reported in other assets on the accompanying consolidated balance sheet.
Securities Held to Maturity	Securities Held to Maturity At both March 31, 2024 and December 31, 2023 , the potential for credit loss exposure for Trustmark's securities held to maturity was $ 340 thousand and consisted of municipal securities. After applying appropriate probability of default (PD) and loss given default (LGD) assumptions, the total amount of current expected credit losses was deemed immaterial. Therefore, no reserve was recorded at March 31, 2024 and December 31, 2023. Accrued interest receivable is excluded from the estimate of credit losses for securities held to maturity. At March 31, 2024 , accrued interest receivable totaled $ 2.7 million for securities held to maturity compared to $ 2.6 million at December 31, 2023 and was reported in other assets on the accompanying consolidated balance sheet. At both March 31, 2024 and December 31, 2023, Trustmark had no securities held to maturity that were past due 30 days or more as to principal or interest payments. Trustmark had no securities held to maturity classified as nonaccrual at March 31, 2024 and December 31, 2023 .
Allowance for Credit Losses, LHFI (ACL)	ACL on LHFI Trustmark’s ACL methodology for LHFI is based upon guidance within the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Subtopic 326-20 as well as applicable regulatory guidance. The ACL is a valuation account that is deducted from the loans’ amortized cost basis to present the net amount expected to be collected on the loans. Credit quality within the LHFI portfolio is continuously monitored by Management and is reflected within the ACL for LHFI. The ACL is an estimate of expected losses inherent within Trustmark’s existing LHFI portfolio. The ACL for LHFI is adjusted through the PCL, LHFI and reduced by the charge off of loan amounts, net of recoveries. The methodology for estimating the amount of expected credit losses reported in the ACL has two basic components: a collective, or pooled, component for estimated expected credit losses for pools of loans that share similar risk characteristics, and an asset-specific component involving individual loans that do not share risk characteristics with other loans and the measurement of expected credit losses for such individual loans. In estimating the ACL for the collective component, loans are segregated into loan pools based on loan product types and similar risk characteristics. The loans secured by real estate and other loans secured by real estate portfolio segments include loans for both commercial and residential properties. The underwriting process for these loans includes analysis of the financial position and strength of both the borrower and guarantor, experience with similar projects in the past, market demand and prospects for successful completion of the proposed project within the established budget and schedule, values of underlying collateral, availability of permanent financing, maximum loan-to-value ratios, minimum equity requirements, acceptable amortization periods and minimum debt service coverage requirements, based on property type. The borrower’s financial strength and capacity to repay their obligations remain the primary focus of underwriting. Financial strength is evaluated based upon analytical tools that consider historical and projected cash flows and performance in addition to analysis of the proposed project for income-producing properties. Additional support offered by guarantors is also considered. Ultimate repayment of these loans is sensitive to interest rate changes, general economic conditions, liquidity and availability of long-term financing. The commercial and industrial LHFI portfolio segment includes loans within Trustmark’s geographic markets made to many types of businesses for various purposes, such as short-term working capital loans that are usually secured by accounts receivable and inventory and term financing for equipment and fixed asset purchases that are secured by those assets. Trustmark’s credit underwriting process for commercial and industrial loans includes analysis of historical and projected cash flows and performance, evaluation of financial strength of both borrowers and guarantors as reflected in current and detailed financial information and evaluation of underlying collateral to support the credit. The consumer LHFI portfolio segment is comprised of loans that are centrally underwritten based on the borrower's credit bureau score as well as an evaluation of the borrower’s repayment capacity, credit, and collateral. Property appraisals are obtained to assist in evaluating collateral. Loan-to-value and debt-to-income ratios, loan amount, and lien position are also considered in assessing whether to originate a loan. These borrowers are particularly susceptible to downturns in economic trends such as conditions that negatively affect housing prices and demand and levels of unemployment. The state and other political subdivision LHFI and the other commercial LHFI and leases portfolio segments primarily consist of loans to non-depository financial institutions, such as mortgage companies, finance companies and other financial intermediaries, loans to state and political subdivisions, and loans to non-profit and charitable organizations. These loans are underwritten based on the specific nature or purpose of the loan and underlying collateral with special consideration given to the specific source of repayment for the loan. The lease segment primarily consists of commercial equipment finance leases. Trustmark’s credit underwriting process for equipment finance leases includes analysis of historical and projected cash flows and performance, evaluation of financial strength of both borrowers and guarantors as reflected in current and detailed financial information and evaluation of underlying collateral to support the credit. During the first quarter of 2024 as part of Trustmark's ongoing model monitoring procedures the annual loss driver analysis was performed. The analysis resulted in changes in the loss drivers for all discounted cash-flow models along with changes in the loss drivers for the equipment and finance loans and leases model. These changes were a result of updating Trustmark's peer group and incorporating data through 2022 which led to more intuitive loss drivers. All models were validated by a third party before implementation. The following table provides a description of each of Trustmark’s portfolio segments, loan classes, loan pools and the ACL methodology and loss drivers at March 31, 2024: Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Loans secured by real estate Construction, land 1-4 family residential DCF National HPI, National Unemployment Lots and development DCF National HPI, National Unemployment Unimproved land DCF National HPI, National Unemployment All other consumer DCF National HPI, National Unemployment Other secured by 1-4 Consumer 1-4 family - 1st liens DCF National HPI, National Unemployment All other consumer DCF National HPI, National Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Secured by nonfarm, Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - office DCF National CRE Price Index, Southern Unemployment Nonowner-occupied- Retail DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - senior DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Other real estate secured Nonresidential nonowner DCF National CRE Price Index, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Other loans secured by Other construction Other construction DCF National CRE Price Index, National Unemployment, BBB 7-10 US CBI Secured by 1-4 family Trustmark mortgage WARM Southern Unemployment Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Commercial and Commercial and Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance loans WARM Southern Unemployment, National GDP Credit cards WARM Trustmark call report data Consumer loans Consumer loans Credit cards WARM Trustmark call report data Overdrafts Loss Rate Trustmark historical data All other consumer DCF National HPI, National Unemployment State and other political State and other political Obligations of state and DCF Moody's Bond Default Study Other commercial loans and leases Other commercial loans and leases Other loans DCF BBB 7-10 US CBI, Southern Unemployment Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance leases WARM Southern Unemployment, National GDP The following table provides a description of each of Trustmark’s portfolio segments, loan classes, loan pools and the ACL methodology and loss drivers at December 31, 2023: Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Loans secured by real estate Construction, land 1-4 family residential DCF Prime Rate, National GDP Lots and development DCF Prime Rate, Southern Unemployment Unimproved land DCF Prime Rate, Southern Unemployment All other consumer DCF Southern Unemployment Other secured by 1-4 Consumer 1-4 family - 1st liens DCF Prime Rate, Southern Unemployment All other consumer DCF Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Secured by nonfarm, Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - office DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied- Retail DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - senior DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Other real estate secured Nonresidential nonowner DCF Southern Vacancy Rate, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Other loans secured by Other construction Other construction DCF Prime Rate, National Unemployment Secured by 1-4 family Trustmark mortgage WARM Southern Unemployment Commercial and Commercial and Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance loans WARM Southern Unemployment, Southern GDP Credit cards WARM Trustmark call report data Consumer loans Consumer loans Credit cards WARM Trustmark call report data Overdrafts Loss Rate Trustmark historical data All other consumer DCF Southern Unemployment State and other political State and other political Obligations of state and DCF Moody's Bond Default Study Other commercial loans and leases Other commercial loans and leases Other loans DCF Prime Rate, Southern Unemployment Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance leases WARM Southern Unemployment, Southern GDP In general, Trustmark utilizes a DCF method to estimate the quantitative portion of the ACL for loan pools. The DCF model consists of two key components, a loss driver analysis (LDA) and a cash flow analysis. For loan pools utilizing the DCF methodology, multiple assumptions are in place, depending on the loan pool. A reasonable and supportable forecast is utilized for each loan pool by developing a LDA for each loan class. The LDA uses charge off data from Federal Financial Institutions Examination Council (FFIEC) reports to construct a periodic default rate (PDR). The PDR is decomposed into a PD. Regressions are run using the data for various macroeconomic variables in order to determine which ones correlate to Trustmark’s losses. These variables are then incorporated into the application to calculate a quarterly PD using a third-party baseline forecast. In addition to the PD, a LGD is derived using a method referred to as Frye Jacobs. The Frye Jacobs method is a mathematical formula that traces the relationship between LGD and PD over time and projects the LGD based on the levels of PD forecasts. This model approach is applicable to all pools within the construction, land development and other land, other secured by 1-4 family residential properties, secured by nonfarm, nonresidential properties and other real estate secured loan classes as well as consumer loans and other commercial loans. During 2022, Management elected to incorporate a methodology change related to the other construction pool. Components of this change include management utilizing an alternative LDA to support the PD and LGD assumptions necessary to apply a DCF methodology to the other construction pool. Fundamentally, this approach utilizes publicly reported default balances and leverages a generalized linear model (GLM) framework to estimate PD. Taken together, these differences allow for results to be scaled to be specific and directly applicable to the other construction segment. LGD is assumed to be a through-the-cycle constant based on the actual performance of Trustmark’s other construction segment. These assumptions are then input into the DCF model and used in conjunction with prepayment data to calculate the cash flows at the individual loan level. Previously, the other construction pool used the weighted average remaining maturity (WARM) method. Management believes this change is commensurate with the level of risk in the pool. For the commercial and industrial loans related pools, Trustmark uses its own PD and LGD data, instead of the macroeconomic variables and the Frye Jacobs method described above, to calculate the PD and LGD as there were no defensible macroeconomic variables that correlated to Trustmark’s losses. Trustmark utilizes a third-party Bond Default Study to derive the PD and LGD for the obligations of state and political subdivisions pool. Due to the lack of losses within this pool, no defensible macroeconomic factors were identified to correlate. The PD and LGD measures are used in conjunction with prepayment data as inputs into the DCF model to calculate the cash flows at the individual loan level. Contractual cash flows based on loan terms are adjusted for PD, LGD and prepayments to derive loss cash flows. These loss cash flows are discounted by the loan’s coupon rate to arrive at the discounted cash flow based quantitative loss. The prepayment studies are updated quarterly by a third-party for each applicable pool. An alternate method of estimating the ACL is used for certain loan pools due to specific characteristics of these loans. For the non-DCF pools, specifically, those using the WARM method, the remaining life is incorporated into the ACL quantitative calculation. Trustmark determined that reasonable and supportable forecasts could be made for a twelve-month period for all of its loan pools. To the extent the lives of the loans in the LHFI portfolio extend beyond this forecast period, Trustmark uses a reversion period of four quarters and reverts to the historical mean on a straight-line basis over the remaining life of the loans. The econometric models currently in production reflect segment or pool level sensitivities of PD to changes in macroeconomic variables. By measuring the relationship between defaults and changes in the economy, the quantitative reserve incorporates reasonable and supportable forecasts of future conditions that will affect the value of Trustmark’s assets, as required by FASB ASC Topic 326. Under stable forecasts, these linear regressions will reasonably predict a pool’s PD. However, due to the COVID-19 pandemic, the macroeconomic variables used for reasonable and supportable forecasting changed rapidly. At the macroeconomic levels experienced during the COVID-19 pandemic, it was not clear that the models in production would produce reasonably representative results since the models were originally estimated using data beginning in 2004 through 2019. During this period, a traditional, albeit severe, economic recession occurred. Thus, econometric models are sensitive to similar future levels of PD. In order to prevent the econometric models from extrapolating beyond reasonable boundaries of their input variables, Trustmark chose to establish an upper and lower limit process when applying the periodic forecasts. In this way, Management will not rely upon unobserved and untested relationships in the setting of the quantitative reserve. This approach applies to all input variables, including: Southern Unemployment, National Unemployment, National Gross Domestic Product (GDP), National Home Price Index (HPI), National Commercial Real Estate (CRE) Price Index and the BBB 7-10 Year US Corporate Bond Index (CBI). The upper and lower limits are based on the distribution of the macroeconomic variable by selecting extreme percentiles at the upper and lower limits of the distribution, the 1 st and 99 th percentiles, respectively. These upper and lower limits are then used to calculate the PD for the forecast time period in which the forecasted values are outside of the upper and lower limit range. Due to multiple periods having a PD or LGD at or near zero as a result of the improving macroeconomic forecasts, Management implemented PD and LGD floors to account for the risk associated with each portfolio. The PD and LGD floors are based on Trustmark’s historical loss experience and applied at a portfolio level. Qualitative factors used in the ACL methodology include the following: • Lending policies and procedures • Economic conditions and concentrations of credit • Nature and volume of the portfolio • Performance trends • External factors While all these factors are incorporated into the overall methodology, only three are currently considered active at March 31, 2024: (i) economic conditions and concentrations of credit, (ii) nature and volume of the portfolio and (iii) performance trends. Two of Trustmark’s largest loan classes are the loans secured by nonfarm, nonresidential properties and the loans secured by other real estate. Trustmark elected to create a qualitative factor specifically for these loan classes which addresses changes in the economic conditions of metropolitan areas and applies additional pool level reserves. This qualitative factor is based on third-party market data and forecast trends and is updated quarterly as information is available, by market and by loan pool. Trustmark's current quantitative methodologies do not completely incorporate changes in credit quality. As a result, Trustmark utilizes the performance trends qualitative factor. This factor is based on migration analyses, that allocates additional ACL to non-pass/delinquent loans within each pool. In this way, Management believes the ACL will directly reflect changes in risk, based on the performance of the loans within a pool, whether declining or improving. The performance trends qualitative factor is estimated by properly segmenting loan pools into risk levels by risk rating for commercial credits and delinquency status for consumer credits. A migration analysis is then performed quarterly using a third-party software and the results for each risk level are compiled to calculate the historical PD average for each loan portfolio based on risk levels. This average historical PD rate is updated annually. For the mortgage portfolio, Trustmark uses an internal report to incorporate a roll rate method for the calculation of the PD rate. In addition to the PD rate for each portfolio, Management incorporates the quantitative rate and the k value derived from the Frye-Jacobs method to calculate a loss estimate that includes both PD and LGD. The quantitative rate is used to eliminate any additional reserve that the quantitative reserve already includes. Finally, the loss estimate rate is then applied to the total balances for each risk level for each portfolio to calculate a qualitative reserve. During 2022, Management elected to activate the nature and volume of the portfolio qualitative factor as a result of a sub-pool of the secured by 1-4 family residential properties growing to a significant size along with the underlying nature being different as well. The nature and volume of the portfolio qualitative factor utilizes a WARM methodology that uses industry data for the assumptions to support the qualitative adjustment. The industry data is used to compile a PD based on credit score ranges along with using the industry data to compile an LGD. The sub-pool of credits is then aggregated into the appropriate credit score bands in which a weighted average loss rate is calculated based on the PD and LGD for each credit score range. This weighted average loss rate is then applied to the expected balance for the sub-segment of credits. This total is then used as the qualitative reserve adjustment. The external factors qualitative factor is Management’s best judgment on the loan or pool level impact of all factors that affect the portfolio that are not accounted for using any other part of the ACL methodology ( e.g. , natural disasters, changes in legislation, impacts due to technology and pandemics). Trustmark's External Factor – Pandemic ensures reserve adequacy for collectively evaluated loans most likely to be impacted by the unique economic and behavioral conditions created by the COVID-19 pandemic. Additional qualitative reserves are derived based on two principles. The first is the disconnect of economic factors to Trustmark’s modeled PD (derived from the econometric models underpinning the quantitative pooled reserves). During the pandemic, extraordinary measures by the federal government were made available to consumers and businesses, including COVID-19 loan payment concessions, direct transfer payments to households, tax deferrals, and reduced interest rates, among others. These government interventions may have extended the lag between economic conditions and default, relative to what was captured in the model development data. Because Trustmark’s econometric PD models rely on the observed relationship from the economic downturn from 2007 to 2009 in both timing and severity, Management did not expect the models to reflect these conditions. For example, while the models would predict contemporaneous unemployment peaks and loan defaults, this might not have occurred when borrowers could request payment deferrals. Thus, for the affected population, economic conditions were not fully considered as a part of Trustmark’s quantitative reserve. The second principle is the change in risk that is identified by rating changes. As a part of Trustmark’s credit review process, loans in the affected population were given more frequent screening to ensure accurate ratings were maintained through this dynamic period. Trustmark’s quantitative reserve did not directly address changes in ratings, thus a migration qualitative factor was designed to work in concert with the quantitative reserve. As discussed above, the disconnect of economic factors means that changes in rating caused by deteriorating and weak economic conditions as a result of the pandemic were not being captured in the quantitative reserve. During 2020, due to unforeseen pandemic conditions that varied from Management’s expectations, additional reserves were further dimensioned in order to appropriately reflect the risk within the portfolio related to the COVID-19 pandemic. In an effort to ensure the External Factor-Pandemic qualitative factor was reasonable and supportable, historical Trustmark loss data was leveraged to construct a framework that was quantitative in nature. To dimension the additional reserve, Management used the sensitivity of the quantitative commercial loan reserve to changes in macroeconomic conditions to apply to loans rated acceptable or better (RR 1-4). In addition, to account for the known changes in risk, a weighted average of the commercial loan portfolio loss rate, derived from the performance trends qualitative factor, was used to dimension additional reserves for downgraded credits. Loans rated acceptable with risk (RR 5) or watch (RR 6) received the additional reserves based on the average of the macroeconomic conditions and weighted-average of the commercial loan portfolio loss rate while the loans rated special mention (RR 7) and substandard (RR 8) received additional reserves based on the weighted-average described above. During 2022, Management noted that all pass rated loans (RR 5 & RR 6) related to the External Factor-Pandemic qualitative factor either did not experience significant stress related to the pandemic or had since recovered and did not expect future stresses attributed to the pandemic that could affect these loans. As a result, Management decided to accelerate the release of the additional pandemic reserves on all pass rated loans as a result of pandemic conditions resolving. During the fourth quarter of 2023, Management decided to resolve the External Factor-Pandemic qualitative factor as a result of the remaining loan balances that were identified as COVID affected loans being immaterial from both a reserve and balance perspective. The remaining loans were incorporated back into the performance qualitative factor as a result of this resolution. Further, due to this resolution there is no longer any active External Factor as of December 31, 2023.
Accounting Policies Recently Adopted	Accounting Policies Recently Adopted Except for the changes detailed below, Trustmark has consistently applied its accounting policies to all periods presented in the accompanying consolidated financial statements. ASU 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” Issued in November 2023, ASU 2023-07 is intended to improve disclosures about a public entity’s reportable segments and address requests from investors and other allocators of capital for additional, more detailed information about a reportable segment’s expenses. The amendments of ASU 2023-07 require a public entity to disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker (CODM) and included within each reported measure of segment profit or loss, and an amount for other segment items by reportable segment and a description of its composition. The other segment items category is the difference between segment revenue less the significant expenses disclosed and each reported measure of segment profit or loss. ASU 2023-07 also requires a public entity to provide all annual disclosures about a reportable segment’s profit or loss and assets currently required under FASB ASC Topic 280 in interim periods. The amendments of ASU 2023-07 clarify that if the CODM uses more than one measure of a segment's profit or loss in assessing segment performance and deciding how to allocate resources, a public entity may report one or more of those additional measures of segment profit. However, at least one of the reported segment profit or loss measures (or the single reported measure if only one is disclosed) should be the measure that is most consistent with the measurement principles used in measuring the corresponding amounts in the public entity's consolidated financial statements. ASU 2023-07 requires a public entity to disclose the title and position of the CODM, together with an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. In addition, ASU 2023-07 requires that a public entity with a single reportable segment provide all the disclosures required by the amendments of ASU 2023-07 and all existing segment disclosures in FASB ASC Topic 280. The amendments of ASU 2023-07 are effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments in ASU 2023-07 should be applied retrospectively to all periods presented on the financial statements. Upon implementation, the segment expense categories and amounts disclosed in the prior periods should be based on the significant segment expense categories identified and disclosed in the period of adoption. Trustmark has adopted the amendments of ASU 2023-07 related to annual disclosure requirements effective January 1, 2024 , and will present any newly required annual disclosures in its Annual Report of Form 10-K for the year ending December 31, 2024. Trustmark intends to adopt the amendments of ASU 2023-07 related to interim disclosure requirements effective January 1, 2025, and will present any newly required interim disclosures beginning with its Quarterly Report on Form 10-Q for the period ending March 31, 2025. Adoption of ASU 2023-07 is no t expected to have a material impact to Trustmark’s consolidated financial statements or results of operations. Pending Accounting Pronouncements ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” Issued in December 2023, ASU 2023-09 is intended to improve the disclosures for income taxes to address requests from investors, lenders, creditors and other allocators of capital (collectively, "investors") that use the financial statements to make capital allocation decisions. During the FASB's 2021 agenda consultation process and other stakeholder outreach, investors highlighted that the current system of income tax disclosures does not provide enough information to understand the tax provision for an entity that operates in multiple jurisdictions. Investors currently rely on the rate reconciliation table and other disclosures, including total income taxes paid in the statement of cash flows, to evaluate income tax risks and opportunities. The amendments in ASU 2023-09 will require consistent categories and greater disaggregation of information in the rate reconciliation disclosure as well as disclosure of income taxes paid disaggregated by jurisdiction. The amendments of ASU 2023-09 are effective for annual periods beginning after December 15, 2024, and early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. Trustmark intends to adopt the amendments of ASU 2023-09 effective January 1, 2025 , and will include the required disclosures in its Annual Report on Form 10-K for the year ending December 31, 2025. Trustmark is currently evaluating the changes to disclosures required by ASU 2023-09; however, adoption of ASU 2023-09 is no t expected to have a material impact to Trustmark’s consolidated financial statements or results of operations.

Securities Available for Sale_2

Securities Available for Sale and Held to Maturity (Tables)	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Amortized Cost and Estimated Fair Value of Available for Sale and Held to Maturity Securities	The following tables are a summary of the amortized cost and estimated fair value of securities available for sale and held to maturity at March 31, 2024 and December 31, 2023 ($ in thousands): Securities Available for Sale Securities Held to Maturity March 31, 2024 Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. Treasury securities $ 396,289 $ — $ ( 23,865 ) $ 372,424 $ 29,261 $ — $ ( 515 ) $ 28,746 U.S. Government agency 6,017 — ( 423 ) 5,594 — — — — Obligations of states and — — — — 340 — — 340 Mortgage-backed securities Residential mortgage pass- Guaranteed by GNMA 25,343 6 ( 3,117 ) 22,232 18,387 — ( 750 ) 17,637 Issued by FNMA and 1,293,149 22 ( 163,650 ) 1,129,521 461,457 46 ( 21,935 ) 439,568 Other residential mortgage- Issued or guaranteed by 85,317 — ( 6,218 ) 79,099 146,447 — ( 10,731 ) 135,716 Commercial mortgage-backed Issued or guaranteed by 94,865 — ( 1,436 ) 93,429 759,133 13 ( 48,139 ) 711,007 Total $ 1,900,980 $ 28 $ ( 198,709 ) $ 1,702,299 $ 1,415,025 $ 59 $ ( 82,070 ) $ 1,333,014 Securities Available for Sale Securities Held to Maturity December 31, 2023 Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. Treasury Securities $ 396,179 $ — $ ( 23,811 ) $ 372,368 $ 29,068 $ — $ ( 26 ) $ 29,042 U.S. Government agency 6,207 1 ( 416 ) 5,792 — — — — Obligations of states and — — — — 340 — — 340 Mortgage-backed securities Residential mortgage pass- Guaranteed by GNMA 25,744 4 ( 2,613 ) 23,135 13,005 — ( 497 ) 12,508 Issued by FNMA and 1,338,256 32 ( 161,490 ) 1,176,798 469,593 — ( 18,205 ) 451,388 Other residential mortgage- Issued or guaranteed by 92,076 — ( 6,002 ) 86,074 154,466 — ( 10,113 ) 144,353 Commercial mortgage-backed Issued or guaranteed by 100,545 — ( 1,834 ) 98,711 759,807 51 ( 41,985 ) 717,873 Total $ 1,959,007 $ 37 $ ( 196,166 ) $ 1,762,878 $ 1,426,279 $ 51 $ ( 70,826 ) $ 1,355,504
Securities Held to Maturity by Credit Rating, as Determined by Moody's	The following table presents the amortized cost of Trustmark’s securities held to maturity by credit rating, as determined by Moody’s, at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Aaa $ 1,414,685 $ 1,425,939 Not Rated (1) 340 340 Total $ 1,415,025 $ 1,426,279 (1) Not rated securities primarily consist of Mississippi municipal general obligations.
Securities with Gross Unrealized Losses, Segregated by Length of Impairment	The tables below include securities with gross unrealized losses for which an allowance for credit losses has not been recorded segregated by length of impairment at March 31, 2024 and December 31, 2023 ($ in thousands): Less than 12 Months 12 Months or More Total March 31, 2024 Estimated Gross Estimated Gross Estimated Gross U.S. Treasury securities $ 28,746 $ ( 515 ) $ 372,424 $ ( 23,865 ) $ 401,170 $ ( 24,380 ) U.S. Government agency obligations — — 5,594 ( 423 ) 5,594 ( 423 ) Mortgage-backed securities Residential mortgage pass-through Guaranteed by GNMA 14,632 ( 343 ) 24,950 ( 3,524 ) 39,582 ( 3,867 ) Issued by FNMA and FHLMC 303,034 ( 5,957 ) 1,259,726 ( 179,628 ) 1,562,760 ( 185,585 ) Other residential mortgage-backed Issued or guaranteed by FNMA, — — 214,805 ( 16,949 ) 214,805 ( 16,949 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, 1,616 ( 55 ) 800,447 ( 49,520 ) 802,063 ( 49,575 ) Total $ 348,028 $ ( 6,870 ) $ 2,677,946 $ ( 273,909 ) $ 3,025,974 $ ( 280,779 ) December 31, 2023 U.S. Treasury Securities $ 29,042 $ ( 26 ) $ 372,368 $ ( 23,811 ) $ 401,410 $ ( 23,837 ) U.S. Government agency obligations — — 5,791 ( 416 ) 5,791 ( 416 ) Mortgage-backed securities Residential mortgage pass-through Guaranteed by GNMA 9,381 ( 172 ) 25,967 ( 2,938 ) 35,348 ( 3,110 ) Issued by FNMA and FHLMC 309,466 ( 3,274 ) 1,311,865 ( 176,421 ) 1,621,331 ( 179,695 ) Other residential mortgage-backed Issued or guaranteed by FNMA, — — 230,368 ( 16,115 ) 230,368 ( 16,115 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, 1,656 ( 13 ) 812,520 ( 43,806 ) 814,176 ( 43,819 ) Total $ 349,545 $ ( 3,485 ) $ 2,758,879 $ ( 263,507 ) $ 3,108,424 $ ( 266,992 )
Contractual Maturities of Available for Sale and Held to Maturity Securities	The amortized cost and estimated fair value of securities available for sale and held to maturity at March 31, 2024, by contractual maturity, are shown below ($ in thousands). Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities Securities Amortized Estimated Amortized Estimated Due in one year or less $ 99,995 $ 98,050 $ 340 $ 340 Due after one year through five years 296,508 274,584 29,261 28,746 Due after five years through ten years 2,236 2,021 — — Due after ten years 3,567 3,363 — — 402,306 378,018 29,601 29,086 Mortgage-backed securities 1,498,674 1,324,281 1,385,424 1,303,928 Total $ 1,900,980 $ 1,702,299 $ 1,415,025 $ 1,333,014

LHFI and ACL, LHFI (Tables)

LHFI and ACL, LHFI (Tables)	3 Months Ended
	Mar. 31, 2024
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Loan Portfolio Held for Investment	At March 31, 2024 and December 31, 2023, LHFI consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Loans secured by real estate: Construction, land development and other land $ 617,008 $ 642,886 Other secured by 1-4 family residential properties 625,387 622,397 Secured by nonfarm, nonresidential properties 3,543,235 3,489,434 Other real estate secured 1,384,610 1,312,551 Other loans secured by real estate: Other construction 922,453 867,793 Secured by 1-4 family residential properties 2,266,094 2,282,318 Commercial and industrial loans 1,922,711 1,922,910 Consumer loans 159,340 165,734 State and other political subdivision loans 1,052,844 1,088,466 Other commercial loans and leases 564,261 556,035 LHFI 13,057,943 12,950,524 Less ACL 142,998 139,367 Net LHFI $ 12,914,945 $ 12,811,157
Schedule of Amortized Cost Basis of Loans on Nonaccrual Status	The following tables provide the amortized cost basis of loans on nonaccrual status and loans past due 90 days or more still accruing interest at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Nonaccrual With No ACL Total Nonaccrual Loans Past Due 90 Days or More Still Accruing Loans secured by real estate: Construction, land development and other land $ 991 $ 1,809 $ — Other secured by 1-4 family residential properties 923 6,843 919 Secured by nonfarm, nonresidential properties 917 3,049 — Other real estate secured — 134 — Other loans secured by real estate: Other construction — 13,098 — Secured by 1-4 family residential properties 4,291 48,877 3,792 Commercial and industrial loans 36 23,089 49 Consumer loans — 238 483 Other commercial loans and leases — 1,214 — Total $ 7,158 $ 98,351 $ 5,243 December 31, 2023 Nonaccrual With No ACL Total Nonaccrual Loans Past Due 90 Days or More Still Accruing Loans secured by real estate: Construction, land development and other land $ 2,020 $ 2,642 $ — Other secured by 1-4 family residential properties 946 6,518 1,238 Secured by nonfarm, nonresidential properties 20,812 23,061 54 Other real estate secured — 158 106 Other loans secured by real estate: Other construction — 62 — Secured by 1-4 family residential properties 3,235 43,815 3,740 Commercial and industrial loans 79 22,303 24 Consumer loans — 243 628 Other commercial loans and leases — 1,206 — Total $ 27,092 $ 100,008 $ 5,790
Aging Analysis of Past Due and Nonaccrual LHFI by Loan Type	The following tables provide an aging analysis of the amortized cost basis of past due LHFI (including nonaccrual LHFI) at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total LHFI Loans secured by real estate: Construction, land development and $ 354 $ 590 $ 1,011 $ 1,955 $ 615,053 $ 617,008 Other secured by 1-4 family residential 6,147 1,554 2,575 10,276 615,111 625,387 Secured by nonfarm, nonresidential 695 711 892 2,298 3,540,937 3,543,235 Other real estate secured — — — — 1,384,610 1,384,610 Other loans secured by real estate: Other construction — 13,038 — 13,038 909,415 922,453 Secured by 1-4 family residential properties 14,706 7,246 25,361 47,313 2,218,781 2,266,094 Commercial and industrial loans 12,207 446 19,018 31,671 1,891,040 1,922,711 Consumer loans 1,616 548 512 2,676 156,664 159,340 State and other political subdivision loans 972 — — 972 1,051,872 1,052,844 Other commercial loans and leases 1,522 116 37 1,675 562,586 564,261 Total $ 38,219 $ 24,249 $ 49,406 $ 111,874 $ 12,946,069 $ 13,057,943 December 31, 2023 Past Due 30-59 Days 60-89 Days 90 Days More Total Past Due Current Total LHFI Loans secured by real estate: Construction, land development and $ 93 $ 507 $ 2,362 $ 2,962 $ 639,924 $ 642,886 Other secured by 1-4 family residential 4,493 1,687 2,716 8,896 613,501 622,397 Secured by nonfarm, nonresidential 1,531 1,063 727 3,321 3,486,113 3,489,434 Other real estate secured 126 — 207 333 1,312,218 1,312,551 Other loans secured by real estate: Other construction 62 — — 62 867,731 867,793 Secured by 1-4 family residential properties 19,298 9,327 22,164 50,789 2,231,529 2,282,318 Commercial and industrial loans 11,881 484 499 12,864 1,910,046 1,922,910 Consumer loans 2,112 772 647 3,531 162,203 165,734 State and other political subdivision loans 152 — — 152 1,088,314 1,088,466 Other commercial loans and leases 1,247 58 — 1,305 554,730 556,035 Total $ 40,995 $ 13,898 $ 29,322 $ 84,215 $ 12,866,309 $ 12,950,524
Impact of Modifications Classified as Troubled Debt Restructurings	The following tables present the amortized cost of LHFI at the end of each of the periods presented of loans modified to borrowers experiencing financial difficulty disaggregated by class of loan and type of modification ($ in thousands). The percentage of the amortized cost basis of LHFI that were modified to borrowers in financial distress as compared to the amortized cost basis of each class of LHFI is also presented below: Three Months Ended March 31, 2024 Term Extension % of Total Class of Loan Loans secured by real estate: Other secured by 1-4 family residential $ 1,461 0.23 % Other loans secured by real estate: Secured by 1-4 family residential properties 813 0.04 % Total $ 2,274 0.02 % Three Months Ended March 31, 2023 Term Extension % of Total Class of Loan Loans secured by real estate: Secured by nonfarm, nonresidential $ 384 0.01 % Other loans secured by real estate: Secured by 1-4 family residential properties 492 0.02 % Total $ 876 0.01 %
Troubled debt restructurings on financial effect	The following tables detail the financial effect of the loan modifications presented above to borrowers experiencing financial difficulty for the periods presented: Three Months Ended March 31, 2024 Financial Effect Term Extension Loans secured by real estate: Other secured by 1-4 family residential properties Modified one loan and multiple lines of credit to amortize over 24 month terms. Other loans secured by real estate: Secured by 1-4 family residential properties Extended the amortization periods on six loans by a weighted-average of 2.99 years. Three Months Ended March 31, 2023 Financial Effect Term Extension Loans secured by real estate: Secured by nonfarm, nonresidential properties Renewed with an extended amortization period and lowered the monthly payment amount for the borrower. Other loans secured by real estate: Secured by 1-4 family residential properties Extended the amortization periods on four loans by a weighted-average of 14 years, which reduced the aggregate monthly payment amounts for the borrowers.
Past Due Modifications Related To Loans Held For Investment	The following tables provide details of the performance of such LHFI that have been modified during the periods presented ($ in thousands): Three Months Ended March 31, 2024 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total Loans secured by real estate: Other secured by 1-4 family residential $ — $ — $ — $ — $ 1,461 $ 1,461 Other loans secured by real estate: Secured by 1-4 family residential properties — — — — 813 813 Total $ — $ — $ — $ — $ 2,274 $ 2,274 Three Months Ended March 31, 2023 Past Due 30-59 Days 60-89 Days 90 Days Total Past Due Current Total Loans secured by real estate: Secured by nonfarm, nonresidential $ — $ — $ — $ — $ 384 $ 384 Other loans secured by real estate: Secured by 1-4 family residential properties — — — — 492 492 Total $ — $ — $ — $ — $ 876 $ 876
Schedule Of Amortized Cost Basis Of Collateral Dependent Loans by Class of Loans	The following tables present the amortized cost basis of collateral-dependent loans by class of loans and collateral type as of March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 Real Estate Vehicles Miscellaneous Total Loans secured by real estate: Construction, land development and $ 1,539 $ — $ — $ 1,539 Other secured by 1-4 family 923 — — 923 Secured by nonfarm, nonresidential 917 — — 917 Other loans secured by real estate: Other construction 13,038 — — 13,038 Secured by 1-4 family residential 4,291 — — 4,291 Commercial and industrial loans 20 36 21,154 21,210 Other commercial loans and leases — — 1,022 1,022 Total $ 20,728 $ 36 $ 22,176 $ 42,940 December 31, 2023 Real Estate Vehicles Miscellaneous Total Loans secured by real estate: Construction, land development and $ 2,020 $ — $ — $ 2,020 Other secured by 1-4 family 946 — — 946 Secured by nonfarm, nonresidential 20,812 — — 20,812 Other loans secured by real estate: Secured by 1-4 family residential 3,235 — — 3,235 Commercial and industrial loans 38 41 21,023 21,102 Other commercial loans and leases — — 967 967 Total $ 27,051 $ 41 $ 21,990 $ 49,082
Carrying Amount of Loans by Credit Quality Indicator	The tables below present the amortized cost basis of loans by credit quality indicator and class of loans based on analyses performed at March 31, 2024 and December 31, 2023 ($ in thousands): Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Commercial LHFI Loans secured by real estate: Construction, land Pass - RR 1 through RR 6 $ 98,031 $ 268,068 $ 77,825 $ 30,055 $ 10,227 $ 3,425 $ 49,281 $ 536,912 Special Mention - RR 7 — — — 354 — — — 354 Substandard - RR 8 — 265 265 1,239 18 19 — 1,806 Doubtful - RR 9 — — — — — — — — Total 98,031 268,333 78,090 31,648 10,245 3,444 49,281 539,072 Current period gross — — — — — ( 24 ) — ( 24 ) Other secured by 1-4 family Pass - RR 1 through RR 6 $ 6,379 $ 32,381 $ 28,573 $ 25,941 $ 13,447 $ 9,086 $ 7,889 $ 123,696 Special Mention - RR 7 28 — 53 44 8 — — 133 Substandard - RR 8 59 165 646 155 21 364 34 1,444 Doubtful - RR 9 — — — — — — — — Total 6,466 32,546 29,272 26,140 13,476 9,450 7,923 125,273 Current period gross — — — — — ( 12 ) — ( 12 ) Secured by nonfarm, Pass - RR 1 through RR 6 $ 167,040 $ 492,579 $ 944,333 $ 505,580 $ 574,763 $ 616,719 $ 132,679 $ 3,433,693 Special Mention - RR 7 — 4,260 19,546 — 133 24,979 — 48,918 Substandard - RR 8 4,794 1,521 1,800 27,323 10,711 13,266 1,129 60,544 Doubtful - RR 9 18 — — — — 57 — 75 Total 171,852 498,360 965,679 532,903 585,607 655,021 133,808 3,543,230 Current period gross — — — ( 2,412 ) — ( 16 ) — ( 2,428 ) Other real estate secured: Pass - RR 1 through RR 6 $ 116,981 $ 114,564 $ 539,374 $ 309,788 $ 209,292 $ 46,190 $ 8,758 $ 1,344,947 Special Mention - RR 7 — — — 64 — 35,876 — 35,940 Substandard - RR 8 99 — 3,028 — 268 31 — 3,426 Doubtful - RR 9 — 45 — — — — — 45 Total 117,080 114,609 542,402 309,852 209,560 82,097 8,758 1,384,358 Current period gross — — — — — — — — Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Commercial LHFI Other loans secured by real Other construction: Pass - RR 1 through RR 6 $ 40,364 $ 208,241 $ 494,239 $ 149,994 $ 16,177 $ — $ 340 $ 909,355 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 60 — 13,038 — — — — 13,098 Doubtful - RR 9 — — — — — — — — Total 40,424 208,241 507,277 149,994 16,177 — 340 922,453 Current period gross — — — — — — — — Commercial and industrial Pass - RR 1 through RR 6 $ 188,609 $ 459,063 $ 323,119 $ 124,545 $ 58,584 $ 70,060 $ 538,649 $ 1,762,629 Special Mention - RR 7 — 12,270 22,693 2,136 554 1,323 20,264 59,240 Substandard - RR 8 2,240 4,831 47,455 13,725 11,842 350 19,884 100,327 Doubtful - RR 9 — — 336 155 — 23 1 515 Total 190,849 476,164 393,603 140,561 70,980 71,756 578,798 1,922,711 Current period gross — ( 3 ) ( 225 ) ( 294 ) ( 8 ) ( 54 ) — ( 584 ) State and other political Pass - RR 1 through RR 6 $ 16,902 $ 122,135 $ 243,470 $ 168,190 $ 96,337 $ 401,066 $ 4,744 $ 1,052,844 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 — — — — — — — — Doubtful - RR 9 — — — — — — — — Total 16,902 122,135 243,470 168,190 96,337 401,066 4,744 1,052,844 Current period gross — — — — — — — — Other commercial loans and leases: Pass - RR 1 through RR 6 $ 44,336 $ 193,567 $ 23,760 $ 26,671 $ 18,877 $ 40,003 $ 214,044 $ 561,258 Special Mention - RR 7 — — — 120 193 — — 313 Substandard - RR 8 992 90 123 25 — — 1,460 2,690 Doubtful - RR 9 — — — — — — — — Total 45,328 193,657 23,883 26,816 19,070 40,003 215,504 564,261 Current period gross — — ( 28 ) — — ( 25 ) — ( 53 ) Total commercial $ 686,932 $ 1,914,045 $ 2,783,676 $ 1,386,104 $ 1,021,452 $ 1,262,837 $ 999,156 $ 10,054,202 Total commercial LHFI $ — $ ( 3 ) $ ( 253 ) $ ( 2,706 ) $ ( 8 ) $ ( 131 ) $ — $ ( 3,101 ) Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Consumer LHFI Loans secured by real estate: Construction, land Current $ 4,808 $ 46,918 $ 15,604 $ 5,300 $ 1,165 $ 2,497 $ 1,562 $ 77,854 Past due 30-89 days — 34 — — — 39 — 73 Past due 90 days or more — — — — — — — — Nonaccrual — — — 6 — 3 — 9 Total 4,808 46,952 15,604 5,306 1,165 2,539 1,562 77,936 Current period gross — — — — — — — — Other secured by 1-4 family Current $ 8,491 $ 24,784 $ 10,059 $ 5,482 $ 4,202 $ 10,754 $ 424,148 $ 487,920 Past due 30-89 days — 30 254 169 60 286 4,451 5,250 Past due 90 days or more — — 5 — 100 48 684 837 Nonaccrual — 7 87 46 10 586 5,371 6,107 Total 8,491 24,821 10,405 5,697 4,372 11,674 434,654 500,114 Current period gross — — ( 5 ) — — — ( 59 ) ( 64 ) Secured by nonfarm, Current $ — $ — $ — $ 5 $ — $ — $ — $ 5 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — — 5 — — — 5 Current period gross — — — — — — — — Other real estate secured: Current $ 131 $ — $ — $ — $ 75 $ 46 $ — $ 252 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total 131 — — — 75 46 — 252 Current period gross — — — — — — — — Term Loans by Origination Year 2024 2023 2022 2021 2020 Prior Revolving Loans Total As of March 31, 2024 Consumer LHFI Other loans secured by real Secured by 1-4 family Current $ 33,184 $ 249,825 $ 871,791 $ 506,872 $ 178,382 $ 355,532 $ — $ 2,195,586 Past due 30-89 days — 2,410 9,575 2,777 830 2,246 — 17,838 Past due 90 days or more — 527 1,175 1,052 127 911 — 3,792 Nonaccrual — 1,765 17,942 12,782 6,080 10,309 — 48,878 Total 33,184 254,527 900,483 523,483 185,419 368,998 — 2,266,094 Current period gross — ( 59 ) ( 315 ) ( 29 ) — ( 8 ) — ( 411 ) Consumer loans: Current $ 20,996 $ 43,982 $ 26,201 $ 8,570 $ 2,098 $ 840 $ 53,867 $ 156,554 Past due 30-89 days 348 518 288 122 1 5 784 2,066 Past due 90 days or more 19 58 66 4 8 — 328 483 Nonaccrual — 64 56 77 19 — 21 237 Total 21,363 44,622 26,611 8,773 2,126 845 55,000 159,340 Current period gross ( 1,544 ) ( 282 ) ( 122 ) ( 20 ) ( 27 ) — ( 753 ) ( 2,748 ) Total consumer LHFI $ 67,977 $ 370,922 $ 953,103 $ 543,264 $ 193,157 $ 384,102 $ 491,216 $ 3,003,741 Total consumer LHFI $ ( 1,544 ) $ ( 341 ) $ ( 442 ) $ ( 49 ) $ ( 27 ) $ ( 8 ) $ ( 812 ) $ ( 3,223 ) Total LHFI $ 754,909 $ 2,284,967 $ 3,736,779 $ 1,929,368 $ 1,214,609 $ 1,646,939 $ 1,490,372 $ 13,057,943 Total current period $ ( 1,544 ) $ ( 344 ) $ ( 695 ) $ ( 2,755 ) $ ( 35 ) $ ( 139 ) $ ( 812 ) $ ( 6,324 ) Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Commercial LHFI Loans secured by real estate: Construction, land Pass - RR 1 through RR 6 $ 359,813 $ 98,742 $ 35,095 $ 10,591 $ 2,036 $ 1,961 $ 52,351 $ 560,589 Special Mention - RR 7 — — 360 — — — — 360 Substandard - RR 8 606 336 1,512 19 — 21 — 2,494 Doubtful - RR 9 — — — — — 24 — 24 Total 360,419 99,078 36,967 10,610 2,036 2,006 52,351 563,467 Current period gross — ( 4 ) ( 10 ) — ( 228 ) — — ( 242 ) Other secured by 1-4 family Pass - RR 1 through RR 6 $ 33,072 $ 30,760 $ 29,159 $ 14,309 $ 8,084 $ 2,822 $ 10,077 $ 128,283 Special Mention - RR 7 — 82 48 10 — — — 140 Substandard - RR 8 220 625 157 22 80 306 98 1,508 Doubtful - RR 9 — — — — — — — — Total 33,292 31,467 29,364 14,341 8,164 3,128 10,175 129,931 Current period gross — — ( 24 ) — — ( 6 ) — ( 30 ) Secured by nonfarm, Pass - RR 1 through RR 6 $ 501,327 $ 919,519 $ 526,412 $ 596,240 $ 323,687 $ 369,250 $ 129,142 $ 3,365,577 Special Mention - RR 7 4,271 14,930 — 138 23,966 — — 43,305 Substandard - RR 8 6,332 1,964 47,491 10,809 8,614 5,200 48 80,458 Doubtful - RR 9 21 — — — 53 13 — 87 Total 511,951 936,413 573,903 607,187 356,320 374,463 129,190 3,489,427 Current period gross — ( 39 ) ( 82 ) — ( 19 ) ( 138 ) — ( 278 ) Other real estate secured: Pass - RR 1 through RR 6 $ 194,141 $ 447,200 $ 332,818 $ 209,757 $ 56,024 $ 11,080 $ 8,880 $ 1,259,900 Special Mention - RR 7 126 2,076 — — 35,881 — — 38,083 Substandard - RR 8 — 14,064 — 290 — 39 — 14,393 Doubtful - RR 9 42 — — — — — — 42 Total 194,309 463,340 332,818 210,047 91,905 11,119 8,880 1,312,418 Current period gross — — — — — — — — Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Commercial LHFI Other loans secured by real Other construction Pass - RR 1 through RR 6 $ 179,676 $ 518,062 $ 149,883 $ 14,062 $ — $ 6 $ 6,042 $ 867,731 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 62 — — — — — — 62 Doubtful - RR 9 — — — — — — — — Total 179,738 518,062 149,883 14,062 — 6 6,042 867,793 Current period gross ( 61 ) — ( 3,392 ) — — — — ( 3,453 ) Commercial and industrial Pass - RR 1 through RR 6 $ 497,730 $ 474,737 $ 158,659 $ 80,646 $ 31,876 $ 44,972 $ 537,527 $ 1,826,147 Special Mention - RR 7 12,570 10,141 3,149 1,381 110 — 126 27,477 Substandard - RR 8 4,797 16,872 13,909 11,958 40 80 21,528 69,184 Doubtful - RR 9 6 58 1 — — 25 12 102 Total 515,103 501,808 175,718 93,985 32,026 45,077 559,193 1,922,910 Current period gross ( 42 ) ( 1,071 ) ( 700 ) ( 138 ) ( 95 ) ( 108 ) ( 7 ) ( 2,161 ) State and other political Pass - RR 1 through RR 6 $ 152,157 $ 247,034 $ 174,812 $ 99,786 $ 32,118 $ 377,225 $ 5,334 $ 1,088,466 Special Mention - RR 7 — — — — — — — — Substandard - RR 8 — — — — — — — — Doubtful - RR 9 — — — — — — — — Total 152,157 247,034 174,812 99,786 32,118 377,225 5,334 1,088,466 Current period gross — — — — — — — — Other commercial loans and leases: Pass - RR 1 through RR 6 $ 211,402 $ 48,947 $ 30,071 $ 21,377 $ 32,837 $ 8,468 $ 201,339 $ 554,441 Special Mention - RR 7 — — — 208 — — 20 228 Substandard - RR 8 106 211 42 — — — 987 1,346 Doubtful - RR 9 — — — — — 20 — 20 Total 211,508 49,158 30,113 21,585 32,837 8,488 202,346 556,035 Current period gross ( 40 ) ( 248 ) — ( 26 ) — — — ( 314 ) Total commercial $ 2,158,477 $ 2,846,360 $ 1,503,578 $ 1,071,603 $ 555,406 $ 821,512 $ 973,511 $ 9,930,447 Total commercial LHFI $ ( 143 ) $ ( 1,362 ) $ ( 4,208 ) $ ( 164 ) $ ( 342 ) $ ( 252 ) $ ( 7 ) $ ( 6,478 ) Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Consumer LHFI Loans secured by real estate: Construction, land Current $ 44,912 $ 23,110 $ 5,973 $ 1,203 $ 1,082 $ 1,864 $ 653 $ 78,797 Past due 30-89 days — 250 — — 30 191 — 471 Past due 90 days or more — — — — — — — — Nonaccrual — — 148 — — 3 — 151 Total 44,912 23,360 6,121 1,203 1,112 2,058 653 79,419 Current period gross — — — — — — — — Other secured by 1-4 family Current $ 29,636 $ 11,366 $ 5,733 $ 4,471 $ 4,313 $ 7,674 $ 417,383 $ 480,576 Past due 30-89 days 225 68 74 4 51 220 4,292 4,934 Past due 90 days or more — 264 — — — 41 934 1,239 Nonaccrual 8 76 48 8 — 616 4,961 5,717 Total 29,869 11,774 5,855 4,483 4,364 8,551 427,570 492,466 Current period gross — ( 100 ) ( 9 ) ( 2 ) ( 10 ) ( 22 ) ( 147 ) ( 290 ) Secured by nonfarm, Current $ — $ — $ 7 $ — $ — $ — $ — $ 7 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — 7 — — — — 7 Current period gross — — — — — — — — Other real estate secured: Current $ — $ — $ — $ 78 $ — $ 55 $ — $ 133 Past due 30-89 days — — — — — — — — Past due 90 days or more — — — — — — — — Nonaccrual — — — — — — — — Total — — — 78 — 55 — 133 Current period gross — — — — — — — — Term Loans by Origination Year 2023 2022 2021 2020 2019 Prior Revolving Loans Total As of December 31, 2023 Consumer LHFI Other loans secured by real Secured by 1-4 family Current $ 258,800 $ 878,893 $ 516,324 $ 180,272 $ 98,552 $ 277,664 $ — $ 2,210,505 Past due 30-89 days 3,370 11,293 5,513 2,121 298 1,664 — 24,259 Past due 90 days or more 376 1,219 1,208 682 — 255 — 3,740 Nonaccrual 678 15,586 11,452 4,884 1,848 9,366 — 43,814 Total 263,224 906,991 534,497 187,959 100,698 288,949 — 2,282,318 Current period gross ( 64 ) ( 930 ) ( 217 ) ( 104 ) — ( 142 ) — ( 1,457 ) Consumer loans: Current $ 59,496 $ 32,767 $ 10,698 $ 2,604 $ 917 $ 294 $ 55,321 $ 162,097 Past due 30-89 days 1,274 475 134 34 5 5 839 2,766 Past due 90 days or more 64 44 3 1 — — 516 628 Nonaccrual 44 65 84 26 — — 24 243 Total 60,878 33,351 10,919 2,665 922 299 56,700 165,734 Current period gross ( 6,138 ) ( 559 ) ( 167 ) ( 43 ) ( 1 ) ( 1 ) ( 2,381 ) ( 9,290 ) Total consumer LHFI $ 398,883 $ 975,476 $ 557,399 $ 196,388 $ 107,096 $ 299,912 $ 484,923 $ 3,020,077 Total consumer LHFI $ ( 6,202 ) $ ( 1,589 ) $ ( 393 ) $ ( 149 ) $ ( 11 ) $ ( 165 ) $ ( 2,528 ) $ ( 11,037 ) Total LHFI $ 2,557,360 $ 3,821,836 $ 2,060,977 $ 1,267,991 $ 662,502 $ 1,121,424 $ 1,458,434 $ 12,950,524 Total current period $ ( 6,345 ) $ ( 2,951 ) $ ( 4,601 ) $ ( 313 ) $ ( 353 ) $ ( 417 ) $ ( 2,535 ) $ ( 17,515 )
Summary of Trustmark's Portfolio Segments, Loan Classes, Loan Pools and the ACL Methodology and Loss Drivers	The following table provides a description of each of Trustmark’s portfolio segments, loan classes, loan pools and the ACL methodology and loss drivers at March 31, 2024: Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Loans secured by real estate Construction, land 1-4 family residential DCF National HPI, National Unemployment Lots and development DCF National HPI, National Unemployment Unimproved land DCF National HPI, National Unemployment All other consumer DCF National HPI, National Unemployment Other secured by 1-4 Consumer 1-4 family - 1st liens DCF National HPI, National Unemployment All other consumer DCF National HPI, National Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Secured by nonfarm, Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - office DCF National CRE Price Index, Southern Unemployment Nonowner-occupied- Retail DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - senior DCF National CRE Price Index, Southern Unemployment Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Other real estate secured Nonresidential nonowner DCF National CRE Price Index, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National CRE Price Index Nonowner-occupied - DCF National CRE Price Index, Southern Unemployment Other loans secured by Other construction Other construction DCF National CRE Price Index, National Unemployment, BBB 7-10 US CBI Secured by 1-4 family Trustmark mortgage WARM Southern Unemployment Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Commercial and Commercial and Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance loans WARM Southern Unemployment, National GDP Credit cards WARM Trustmark call report data Consumer loans Consumer loans Credit cards WARM Trustmark call report data Overdrafts Loss Rate Trustmark historical data All other consumer DCF National HPI, National Unemployment State and other political State and other political Obligations of state and DCF Moody's Bond Default Study Other commercial loans and leases Other commercial loans and leases Other loans DCF BBB 7-10 US CBI, Southern Unemployment Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance leases WARM Southern Unemployment, National GDP The following table provides a description of each of Trustmark’s portfolio segments, loan classes, loan pools and the ACL methodology and loss drivers at December 31, 2023: Portfolio Segment Loan Class Loan Pool Methodology Loss Drivers Loans secured by real estate Construction, land 1-4 family residential DCF Prime Rate, National GDP Lots and development DCF Prime Rate, Southern Unemployment Unimproved land DCF Prime Rate, Southern Unemployment All other consumer DCF Southern Unemployment Other secured by 1-4 Consumer 1-4 family - 1st liens DCF Prime Rate, Southern Unemployment All other consumer DCF Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Secured by nonfarm, Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - office DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied- Retail DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - senior DCF Southern Vacancy Rate, Southern Unemployment Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Other real estate secured Nonresidential nonowner DCF Southern Vacancy Rate, Southern Unemployment Nonresidential owner-occupied DCF Southern Unemployment, National GDP Nonowner-occupied - DCF Southern Vacancy Rate, Southern Unemployment Other loans secured by Other construction Other construction DCF Prime Rate, National Unemployment Secured by 1-4 family Trustmark mortgage WARM Southern Unemployment Commercial and Commercial and Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance loans WARM Southern Unemployment, Southern GDP Credit cards WARM Trustmark call report data Consumer loans Consumer loans Credit cards WARM Trustmark call report data Overdrafts Loss Rate Trustmark historical data All other consumer DCF Southern Unemployment State and other political State and other political Obligations of state and DCF Moody's Bond Default Study Other commercial loans and leases Other commercial loans and leases Other loans DCF Prime Rate, Southern Unemployment Commercial and industrial - DCF Trustmark historical data Commercial and industrial - DCF Trustmark historical data Equipment finance leases WARM Southern Unemployment, Southern GDP
Change in Allowance for Loan Losses	The following tables disaggregate the ACL and the amortized cost basis of the loans by the measurement methodology used at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 ACL LHFI Individually Evaluated for Credit Loss Collectively Evaluated for Credit Loss Total Individually Evaluated for Credit Loss Collectively Evaluated for Credit Loss Total Loans secured by real estate: Construction, land development and $ 12 $ 5,731 $ 5,743 $ 1,539 615,469 $ 617,008 Other secured by 1-4 family residential — 10,554 10,554 923 624,464 625,387 Secured by nonfarm, nonresidential — 33,292 33,292 917 3,542,318 3,543,235 Other real estate secured — 9,251 9,251 — 1,384,610 1,384,610 Other loans secured by real estate: Other construction 626 11,439 12,065 13,038 909,415 922,453 Secured by 1-4 family residential — 31,946 31,946 4,291 2,261,803 2,266,094 Commercial and industrial loans 10,960 16,970 27,930 21,210 1,901,501 1,922,711 Consumer loans — 5,523 5,523 — 159,340 159,340 State and other political subdivision loans — 638 638 — 1,052,844 1,052,844 Other commercial loans and leases 1,022 5,034 6,056 1,022 563,239 564,261 Total $ 12,620 $ 130,378 $ 142,998 $ 42,940 $ 13,015,003 $ 13,057,943 December 31, 2023 ACL LHFI Individually Evaluated for Credit Loss Collectively Evaluated for Credit Loss Total Individually Evaluated for Credit Loss Collectively Evaluated for Credit Loss Total Loans secured by real estate: Construction, land development and $ — $ 17,192 $ 17,192 $ 2,020 $ 640,866 $ 642,886 Other secured by 1-4 family residential — 12,942 12,942 946 621,451 622,397 Secured by nonfarm, nonresidential — 24,043 24,043 20,812 3,468,622 3,489,434 Other real estate secured — 4,488 4,488 — 1,312,551 1,312,551 Other loans secured by real estate: Other construction — 5,758 5,758 — 867,793 867,793 Secured by 1-4 family residential — 34,794 34,794 3,235 2,279,083 2,282,318 Commercial and industrial loans 11,436 15,202 26,638 21,102 1,901,808 1,922,910 Consumer loans — 5,794 5,794 — 165,734 165,734 State and other political subdivision loans — 646 646 — 1,088,466 1,088,466 Other commercial loans and leases 967 6,105 7,072 967 555,068 556,035 Total $ 12,403 $ 126,964 $ 139,367 $ 49,082 $ 12,901,442 $ 12,950,524 Changes in the ACL, LHFI were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 139,367 $ 120,214 Loans charged-off ( 6,324 ) ( 2,996 ) Recoveries 2,247 1,777 Net (charge-offs) recoveries ( 4,077 ) ( 1,219 ) PCL, LHFI 7,708 3,244 Balance at end of period $ 142,998 $ 122,239 The following tables detail changes in the ACL, LHFI by loan class for the periods presented ($ in thousands): Three Months Ended March 31, 2024 Balance at Beginning of Period Charge-offs Recoveries PCL Balance at Loans secured by real estate: Construction, land development and other land $ 17,192 $ ( 24 ) $ 1 $ ( 11,426 ) $ 5,743 Other secured by 1-4 family residential properties 12,942 ( 76 ) 450 ( 2,762 ) 10,554 Secured by nonfarm, nonresidential properties 24,043 ( 2,428 ) 9 11,668 33,292 Other real estate secured 4,488 — — 4,763 9,251 Other loans secured by real estate: Other construction 5,758 — 17 6,290 12,065 Secured by 1-4 family residential properties 34,794 ( 411 ) 38 ( 2,475 ) 31,946 Commercial and industrial loans 26,638 ( 584 ) 198 1,678 27,930 Consumer loans 5,794 ( 2,748 ) 1,505 972 5,523 State and other political subdivision loans 646 — — ( 8 ) 638 Other commercial loans and leases 7,072 ( 53 ) 29 ( 992 ) 6,056 Total $ 139,367 $ ( 6,324 ) $ 2,247 $ 7,708 $ 142,998 Three Months Ended March 31, 2023 Balance at Beginning of Period Charge-offs Recoveries PCL Balance at Loans secured by real estate: Construction, land development and other land $ 12,828 $ ( 14 ) $ 8 $ 438 $ 13,260 Other secured by 1-4 family residential properties 12,374 ( 34 ) 47 ( 469 ) 11,918 Secured by nonfarm, nonresidential properties 19,488 ( 28 ) 96 ( 916 ) 18,640 Other real estate secured 4,743 — 3 ( 2,384 ) 2,362 Other loans secured by real estate: Other construction 15,132 — 30 ( 692 ) 14,470 Secured by 1-4 family residential properties 21,185 ( 294 ) 6 5,259 26,156 Commercial and industrial loans 23,140 ( 471 ) 270 523 23,462 Consumer loans 5,792 ( 2,155 ) 1,317 578 5,532 State and other political subdivision loans 885 — — ( 156 ) 729 Other commercial loans and leases 4,647 — — 1,063 5,710 Total $ 120,214 $ ( 2,996 ) $ 1,777 $ 3,244 $ 122,239

Mortgage Banking (Tables)

Mortgage Banking (Tables)	3 Months Ended
	Mar. 31, 2024
Mortgage Banking [Abstract]
Schedule of Activity in the Mortgage Servicing Rights	The activity in the MSR is detailed in the table below for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 131,870 $ 129,677 Origination of servicing assets 2,977 2,646 Change in fair value: Due to market changes 5,123 ( 3,972 ) Due to run-off ( 1,926 ) ( 1,145 ) Balance at end of period $ 138,044 $ 127,206
Schedule of Mortgage Loans Sold and Serviced for Others	The table below details the mortgage loans sold and serviced for others at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Federal National Mortgage Association $ 4,831,183 $ 4,826,028 Government National Mortgage Association 3,557,236 3,510,983 Federal Home Loan Mortgage Corporation 137,725 112,352 Other 27,090 28,012 Total mortgage loans sold and serviced for others $ 8,553,234 $ 8,477,375

Other Real Estate (Tables)

Other Real Estate (Tables)	3 Months Ended
	Mar. 31, 2024
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
Changes and Gains (Losses), Net on Other Real Estate	For the periods presented, changes and gains (losses), net on other real estate were as follows ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 6,867 $ 1,986 Additions 2,228 300 Disposals ( 957 ) ( 542 ) (Write-downs) recoveries ( 518 ) ( 60 ) Balance at end of period $ 7,620 $ 1,684 Gains (losses), net on the sale of other real estate included in $ ( 55 ) $ ( 77 )
Other Real Estate, by Type of Property	At March 31, 2024 and December 31, 2023, other real estate by type of property consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 1-4 family residential properties $ 3,619 $ 1,977 Nonfarm, nonresidential properties 3,946 4,835 Other real estate properties 55 55 Total other real estate $ 7,620 $ 6,867
Other Real Estate, by Geographic Location	At March 31, 2024 and December 31, 2023, other real estate by geographic location consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Alabama $ 1,050 $ 1,397 Florida 71 — Mississippi (1) 2,870 1,242 Tennessee (2) 86 — Texas 3,543 4,228 Total other real estate $ 7,620 $ 6,867 (1) Mississippi includes Central and Southern Mississippi Regions. (2) Tennessee includes Memphis, Tennessee and Northern Mississippi Regions.

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2024
Leases [Abstract]
Components of the Trustmark's Net Investment in its Sales-Type and Direct Financing Leases	The table below summarizes the components of Trustmark's net investment in its sales-type and direct financing leases for the periods presented ($ in thousands): March 31, 2024 December 31, 2023 Leases receivable $ 202,112 $ 161,319 Unearned income ( 35,463 ) ( 29,011 ) Initial direct costs 1,737 1,326 Unguaranteed lease residual 5,577 4,101 Total net investment $ 173,963 $ 137,735
Minimum Future Lease Payments for Trustmark's Leases Receivable	The table below details the minimum future lease payments for Trustmark's leases receivable at March 31, 2024 ($ in thousands): March 31, 2024 2024 (excluding the three months ended March 31, 2024) $ 24,711 2025 33,074 2026 31,972 2027 44,528 2028 28,216 Thereafter 39,611 Lease receivable $ 202,112
Components of Net Lease Cost	The following table details the components of net lease cost for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Finance leases: Amortization of right-of-use assets $ 113 $ 357 Interest on lease liabilities 38 42 Operating lease cost 1,294 1,285 Short-term lease cost 21 89 Variable lease cost 215 255 Sublease income ( 3 ) ( 3 ) Net lease cost $ 1,678 $ 2,025
Cash Payments Included in Measurement of Lease Liabilities	The following table details the cash payments included in the measurement of lease liabilities during the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Finance leases: Operating cash flows included in operating activities $ 38 $ 42 Financing cash flows included in payments under finance lease obligations 99 342 Operating leases: Operating cash flows (fixed payments) included in other operating activities, net 1,212 1,242 Operating cash flows (liability reduction) included in other operating activities, net 865 944
Balance Sheet Information and Weighted-Average Lease Terms and Discount Rates Related to Leases	The following table details balance sheet information, as well as weighted-average lease terms and discount rates, related to leases at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Finance lease right-of-use assets, net of accumulated depreciation $ 3,638 $ 3,751 Finance lease liabilities 4,234 4,334 Operating lease right-of-use assets 36,659 38,142 Operating lease liabilities 40,185 41,584 Weighted-average lease term: Finance leases 8.09 years 8.34 years Operating leases 10.00 years 10.13 years Weighted-average discount rate: Finance leases 3.61 % 3.61 % Operating leases 3.64 % 3.64 %
Future Minimum Rental Commitments Under Finance and Operating Leases	At March 31, 2024, future minimum rental commitments under finance and operating leases were as follows ($ in thousands): Finance Leases Operating Leases 2024 (excluding the three months ended March 31, 2024) $ 435 $ 3,718 2025 584 4,998 2026 589 4,846 2027 594 4,900 2028 599 4,749 Thereafter 2,086 25,452 Total minimum lease payments 4,887 48,663 Less imputed interest ( 653 ) ( 8,478 ) Lease liabilities $ 4,234 $ 40,185

Deposits (Tables)

Deposits (Tables)	3 Months Ended
	Mar. 31, 2024
Deposits [Abstract]
Deposits Summary	At March 31, 2024 and December 31, 2023, deposits consisted of the following ($ in thousands): March 31, 2024 December 31, 2023 Noninterest-bearing demand $ 3,039,652 $ 3,197,620 Interest-bearing demand 5,226,089 4,947,626 Savings 3,750,392 4,047,853 Time 3,322,424 3,376,664 Total $ 15,338,557 $ 15,569,763

Securities Sold Under Repurch_2

Securities Sold Under Repurchase Agreements (Tables)	3 Months Ended
	Mar. 31, 2024
Securities Sold under Agreements to Repurchase [Abstract]
Schedule of Securities Sold Under Repurchase Agreements	The following table presents the securities sold under repurchase agreements by collateral pledged at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Mortgage-backed securities Residential mortgage pass-through securities Issued by FNMA and FHLMC $ 39,437 $ 28,600 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 285 526 Total securities sold under repurchase agreements $ 39,722 $ 29,126

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Summary of Noninterest Income Disaggregated by Reportable Operating Segment and Revenue Stream	The following table presents noninterest income disaggregated by reportable operating segment and revenue stream for the periods presented ($ in thousands): Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Topic 606 Not Topic (1) Total Topic 606 Not Topic (1) Total General Banking Segment Service charges on deposit accounts $ 10,936 $ — $ 10,936 $ 10,315 $ — $ 10,315 Bank card and other fees 7,192 200 7,392 7,643 149 7,792 Mortgage banking, net — 8,915 8,915 — 7,639 7,639 Wealth management 189 — 189 233 — 233 Other, net 3,348 ( 382 ) 2,966 2,988 ( 608 ) 2,380 Total noninterest income $ 21,665 $ 8,733 $ 30,398 $ 21,179 $ 7,180 $ 28,359 Wealth Management Segment Service charges on deposit accounts $ 22 $ — $ 22 $ 21 $ — $ 21 Bank card and other fees 36 — 36 11 — 11 Wealth management 8,763 — 8,763 8,547 — 8,547 Other, net 42 94 136 45 95 140 Total noninterest income $ 8,863 $ 94 $ 8,957 $ 8,624 $ 95 $ 8,719 Insurance Segment Insurance commissions $ 15,464 $ — $ 15,464 $ 14,305 $ — $ 14,305 Other, net 530 — 530 ( 6 ) — ( 6 ) Total noninterest income $ 15,994 $ — $ 15,994 $ 14,299 $ — $ 14,299 Consolidated Service charges on deposit accounts $ 10,958 $ — $ 10,958 $ 10,336 $ — $ 10,336 Bank card and other fees 7,228 200 7,428 7,654 149 7,803 Mortgage banking, net — 8,915 8,915 — 7,639 7,639 Insurance commissions 15,464 — 15,464 14,305 — 14,305 Wealth management 8,952 — 8,952 8,780 — 8,780 Other, net 3,920 ( 288 ) 3,632 3,027 ( 513 ) 2,514 Total noninterest income $ 46,522 $ 8,827 $ 55,349 $ 44,102 $ 7,275 $ 51,377 (1) Noninterest income not in scope for FASB ASC Topic 606 includes customer derivatives revenue and miscellaneous credit card fee income within bank card and other fees; mortgage banking, net; amortization of tax credits, accretion of the FDIC indemnification asset, cash surrender value on various life insurance policies, earnings on Trustmark’s non-qualified deferred compensation plans, other partnership investments and rental income within other, net; and security gains (losses), net.

Defined Benefit and Other Pos_2

Defined Benefit and Other Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2024
Trustmark Capital Accumulation Plan [Member]
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost	The following table presents information regarding the net periodic benefit cost for the Continuing Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Service cost $ 10 $ 13 Interest cost 62 73 Expected return on plan assets ( 24 ) ( 26 ) Recognized net loss due to lump sum settlements — 25 Net periodic benefit cost $ 48 $ 85
Supplemental Retirement Plan [Member]
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost	The following table presents information regarding the net periodic benefit cost for Trustmark’s nonqualified supplemental retirement plans for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Service cost $ 11 $ 17 Interest cost 477 520 Amortization of prior service cost 28 28 Recognized net actuarial loss 95 77 Net periodic benefit cost $ 611 $ 642

Stock and Incentive Compensat_2

Stock and Incentive Compensation (Tables)	3 Months Ended
	Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]
Summary of Stock Plan Activity	The following table summarizes the Stock Plan activity for the period presented: Three Months Ended March 31, 2024 Performance Time-Vested Nonvested units, beginning of period 174,214 358,252 Granted 89,928 139,226 Released from restriction ( 54,973 ) ( 103,594 ) Forfeited — ( 2,334 ) Nonvested units, end of period 209,169 391,550
Compensation Expense for Awards and Units Under Stock Plan	The following table presents information regarding compensation expense for units under the Stock Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Performance units $ 462 $ 278 Time-vested units 1,776 1,437 Total compensation expense $ 2,238 $ 1,715

Contingencies (Tables)

Contingencies (Tables)	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Summary of Changes in ACL on Off-Balance Sheet Credit Exposures	Changes in the ACL on off-balance sheet credit exposures were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Balance at beginning of period $ 34,057 $ 36,838 PCL, off-balance sheet credit exposures ( 192 ) ( 2,242 ) Balance at end of period $ 33,865 $ 34,596

Earnings Per Share (EPS) (Table

Earnings Per Share (EPS) (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share [Abstract]
Weighted-Average Shares Used to Calculate Basic and Diluted EPS	The following table reflects weighted-average shares used to calculate basic and diluted EPS for the periods presented (in thousands): Three Months Ended March 31, 2024 2023 Basic shares 61,128 61,011 Dilutive shares 220 182 Diluted shares 61,348 61,193

Statements of Cash Flows (Table

Statements of Cash Flows (Tables)	3 Months Ended
	Mar. 31, 2024
Supplemental Cash Flow Information [Abstract]
Cash Flows Supplementary Disclosures	The following table reflects specific transaction amounts for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Interest expense paid on deposits and borrowings $ 98,327 $ 54,823 Noncash transfers from loans to other real estate 2,228 300

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2024
Stockholders' Equity Note [Abstract]
Table of Actual Regulatory Capital Amounts and Ratios	The following table provides Trustmark’s and TNB’s actual regulatory capital amounts and ratios under regulatory capital standards in effect at March 31, 2024 and December 31, 2023 ($ in thousands): Actual Regulatory Capital Minimum To Be Well Amount Ratio Requirement Capitalized At March 31, 2024: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,543,460 10.12 % 7.00 % n/a Trustmark National Bank 1,620,495 10.62 % 7.00 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,603,460 10.51 % 8.50 % n/a Trustmark National Bank 1,620,495 10.62 % 8.50 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,895,697 12.42 % 10.50 % n/a Trustmark National Bank 1,789,195 11.73 % 10.50 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,603,460 8.76 % 4.00 % n/a Trustmark National Bank 1,620,495 8.87 % 4.00 % 5.00 % At December 31, 2023: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,521,665 10.04 % 7.00 % n/a Trustmark National Bank 1,602,327 10.58 % 7.00 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,581,665 10.44 % 8.50 % n/a Trustmark National Bank 1,602,327 10.58 % 8.50 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,862,246 12.29 % 10.50 % n/a Trustmark National Bank 1,759,426 11.61 % 10.50 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,581,665 8.62 % 4.00 % n/a Trustmark National Bank 1,602,327 8.75 % 4.00 % 5.00 %
Net Change in Components of Accumulated Other Comprehensive Income (Loss) and the Related Tax Effects	The following table presents the net change in the components of accumulated other comprehensive income (loss) and the related tax effects allocated to each component for the periods presented ($ in thousands). Three Months Ended March 31, 2024 Three Months Ended March 31, 2023 Before Tax Tax (Expense) Net of Tax Before Tax Tax (Expense) Net of Tax Securities available for sale and transferred securities: Net unrealized holding gains (losses) arising $ ( 2,552 ) $ 638 $ ( 1,914 ) $ 30,534 $ ( 7,404 ) $ 23,130 Change in net unrealized holding loss on 3,661 ( 915 ) 2,746 3,859 ( 965 ) 2,894 Total securities available for sale 1,109 ( 277 ) 832 34,393 ( 8,369 ) 26,024 Pension and other postretirement benefit plans: Reclassification adjustments for changes Net change in prior service costs 28 ( 7 ) 21 28 ( 7 ) 21 Recognized net loss due to lump sum — — — 25 ( 6 ) 19 Change in net actuarial loss 95 ( 24 ) 71 77 ( 19 ) 58 Total pension and other postretirement 123 ( 31 ) 92 130 ( 32 ) 98 Cash flow hedge derivatives: Change in accumulated gain (loss) on effective ( 15,960 ) 3,990 ( 11,970 ) 6,269 ( 1,567 ) 4,702 Reclassification adjustment for (gain) loss realized 4,820 ( 1,205 ) 3,615 2,931 ( 733 ) 2,198 Total cash flow hedge derivatives ( 11,140 ) 2,785 ( 8,355 ) 9,200 ( 2,300 ) 6,900 Total other comprehensive income (loss) $ ( 9,908 ) $ 2,477 $ ( 7,431 ) $ 43,723 $ ( 10,701 ) $ 33,022
Summary of Changes in Balances of Accumulated Other Comprehensive Income (Loss)	The following table presents the changes in the balances of each component of accumulated other comprehensive income (loss) for the periods presented ($ in thousands). All amounts are presented net of tax. Securities for Sale Defined Cash Flow Total Balance at January 1, 2024 $ ( 204,670 ) $ ( 6,075 ) $ ( 8,978 ) $ ( 219,723 ) Other comprehensive income (loss) before reclassification 832 — ( 11,970 ) ( 11,138 ) Amounts reclassified from accumulated other — 92 3,615 3,707 Net other comprehensive income (loss) 832 92 ( 8,355 ) ( 7,431 ) Balance at March 31, 2024 $ ( 203,838 ) $ ( 5,983 ) $ ( 17,333 ) $ ( 227,154 ) Balance at January 1, 2023 $ ( 254,442 ) $ ( 5,792 ) $ ( 15,169 ) $ ( 275,403 ) Other comprehensive income (loss) before reclassification 26,024 — 4,702 30,726 Amounts reclassified from accumulated other — 98 2,198 2,296 Net other comprehensive income (loss) 26,024 98 6,900 33,022 Balance at March 31, 2023 $ ( 228,418 ) $ ( 5,694 ) $ ( 8,269 ) $ ( 242,381 )

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value Recurring Basis	The following tables summarize financial assets and financial liabilities measured at fair value on a recurring basis at March 31, 2024 and December 31, 2023, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value ($ in thousands). There were no transfers between fair value levels for the three months ended March 31, 2024 and the year ended December 31, 2023. March 31, 2024 Total Level 1 Level 2 Level 3 U.S. Treasury securities $ 372,424 $ 372,424 $ — $ — U.S. Government agency obligations 5,594 — 5,594 — Mortgage-backed securities 1,324,281 — 1,324,281 — Securities available for sale 1,702,299 372,424 1,329,875 — LHFS 172,937 — 172,937 — MSR 138,044 — — 138,044 Other assets - derivatives 16,953 1,152 14,644 1,157 Other liabilities - derivatives 40,803 102 40,701 — December 31, 2023 Total Level 1 Level 2 Level 3 U.S. Treasury securities $ 372,368 $ 372,368 $ — $ — U.S. Government agency obligations 5,792 — 5,792 — Mortgage-backed securities 1,384,718 — 1,384,718 — Securities available for sale 1,762,878 372,368 1,390,510 — LHFS 184,812 — 184,812 — MSR 131,870 — — 131,870 Other assets - derivatives 23,316 7,685 14,786 845 Other liabilities - derivatives 35,600 21 35,579 —
Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis	The changes in Level 3 assets measured at fair value on a recurring basis for the three months ended March 31, 2024 and 2023 are summarized as follows ($ in thousands): MSR Other Assets - Balance, January 1, 2024 $ 131,870 $ 845 Total net (loss) gain included in Mortgage banking, net (1) 3,197 1,047 Additions 2,977 — Sales — ( 735 ) Balance, March 31, 2024 $ 138,044 $ 1,157 The amount of total gains (losses) for the period included in earnings $ 5,123 $ 927 Balance, January 1, 2023 $ 129,677 $ 157 Total net (loss) gain included in Mortgage banking, net (1) ( 5,117 ) 1,288 Additions 2,646 — Sales — ( 105 ) Balance, March 31, 2023 $ 127,206 $ 1,340 The amount of total gains (losses) for the period included in $ ( 3,972 ) $ 531 (1) Total net (loss) gain included in Mortgage banking, net relating to the MSR includes changes in fair value due to market changes and due to run-off.
Carrying Amounts and Estimated Fair Values of Financial Instruments	The carrying amounts and estimated fair values of financial instruments at March 31, 2024 and December 31, 2023, are as follows ($ in thousands): March 31, 2024 December 31, 2023 Carrying Estimated Carrying Estimated Financial Assets: Level 2 Inputs: Cash and short-term investments $ 606,261 $ 606,261 $ 975,543 $ 975,543 Securities held to maturity 1,415,025 1,333,014 1,426,279 1,355,504 Level 3 Inputs: Net LHFI 12,914,945 12,809,237 12,811,157 12,762,505 Financial Liabilities: Level 2 Inputs: Deposits 15,338,557 15,320,852 15,569,763 15,553,417 Federal funds purchased and securities sold under 393,215 393,215 405,745 405,745 Other borrowings 482,027 482,024 483,230 483,226 Subordinated notes 123,537 110,625 123,482 108,125 Junior subordinated debt securities 61,856 47,011 61,856 48,856
Fair Value and the Contractual Principal Outstanding of the LHFS	The following table provides information about the fair value and the contractual principal outstanding of LHFS accounted for under the fair value option at March 31, 2024 and December 31, 2023 ($ in thousands): March 31, 2024 December 31, 2023 Fair value of LHFS $ 95,197 $ 105,974 LHFS contractual principal outstanding 93,598 102,994 Fair value less unpaid principal $ 1,599 $ 2,980

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments	The following tables disclose the fair value of derivative instruments in Trustmark’s consolidated balance sheets at March 31, 2024 and December 31, 2023 as well as the effect of these derivative instruments on Trustmark’s results of operations for the periods presented ($ in thousands): March 31, 2024 December 31, 2023 Derivatives in hedging relationships: Interest rate contracts: Interest rate swaps included in other assets (1) $ 49 $ 1,182 Interest rate floors included in other assets 1,591 1,689 Interest rate swaps included in other liabilities (1) 2,442 267 Derivatives not designated as hedging instruments: Interest rate contracts: Exchange traded purchased options included in other assets $ 17 $ 180 OTC written options (rate locks) included in other assets 1,157 845 Futures contracts included in other assets 1,135 7,505 Interest rate swaps included in other assets (1) 13,000 11,910 Credit risk participation agreements included in other assets 4 5 Forward contracts included in other liabilities 208 994 Exchange traded written options included in other liabilities 102 21 Interest rate swaps included in other liabilities (1) 38,019 34,255 Credit risk participation agreements included in other liabilities 32 63 (1) In accordance with GAAP, the variation margin collateral payments made or received for interest rate swaps that are centrally cleared are legally characterized as settled. As a result, the centrally cleared interest rate swaps included in other assets and other liabilities are presented on a net basis in the accompanying consolidated balance sheets.
Effects of Derivative Instruments on Statements of Operations	Three Months Ended March 31, 2024 2023 Derivatives in hedging relationships: Amount of gain (loss) reclassified from accumulated other $ ( 4,820 ) $ ( 2,931 ) Derivatives not designated as hedging instruments: Amount of gain (loss) recognized in mortgage banking, net $ ( 5,126 ) $ 2,455 Amount of gain (loss) recognized in bank card and other fees ( 56 ) ( 10 )
Schedule of Amount Included in Other Comprehensive Income for Derivative Instruments Designated as Hedges of Cash Flows	The following table discloses the amount included in other comprehensive income (loss), net of tax, for derivative instruments designated as cash flow hedges for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 Derivatives in cash flow hedging relationship Amount of gain (loss) recognized in other comprehensive $ ( 11,970 ) $ 4,702
Information about Financial Instruments that are Eligible for Offset in the Consolidated Balance Sheets	Information about financial instruments that are eligible for offset in the consolidated balance sheets as of March 31, 2024 and December 31, 2023 is presented in the following tables ($ in thousands): Offsetting of Derivative Assets As of March 31, 2024 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 14,640 $ — $ 14,640 $ ( 3,746 ) $ ( 2,500 ) $ 8,394 Offsetting of Derivative Liabilities As of March 31, 2024 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 40,461 $ — $ 40,461 $ ( 3,746 ) $ ( 40 ) $ 36,675 Offsetting of Derivative Assets As of December 31, 2023 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 14,781 $ — $ 14,781 $ ( 4,339 ) $ — $ 10,442 Offsetting of Derivative Liabilities As of December 31, 2023 Gross Amounts Not Offset in the Gross Gross Amounts Net Amounts of Financial Cash Collateral Net Amount Derivatives $ 34,522 $ — $ 34,522 $ ( 4,339 ) $ ( 2,040 ) $ 28,143

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2024
Segment Reporting [Abstract]
Schedule of Segment Information	The following table discloses financial information by reportable segment for the periods presented ($ in thousands): Three Months Ended March 31, 2024 2023 General Banking Net interest income $ 131,517 $ 136,159 Provision for credit losses 7,348 934 Noninterest income 30,398 28,359 Noninterest expense 111,708 109,590 Income before income taxes 42,859 53,994 Income taxes 6,309 7,924 General banking net income $ 36,550 $ 46,070 Selected Financial Information Total assets $ 18,093,454 $ 18,578,910 Depreciation and amortization $ 8,367 $ 7,443 Wealth Management Net interest income $ 1,316 $ 1,439 Provision for credit losses 168 68 Noninterest income 8,957 8,719 Noninterest expense 7,991 8,034 Income before income taxes 2,114 2,056 Income taxes 523 513 Wealth management net income $ 1,591 $ 1,543 Selected Financial Information Total assets $ 178,165 $ 207,414 Depreciation and amortization $ 62 $ 69 Insurance Net interest income $ ( 3 ) $ ( 3 ) Noninterest income 15,994 14,299 Noninterest expense 11,447 10,703 Income before income taxes 4,544 3,593 Income taxes 1,150 906 Insurance net income $ 3,394 $ 2,687 Selected Financial Information Total assets $ 104,993 $ 90,854 Depreciation and amortization $ 134 $ 154 Consolidated Net interest income $ 132,830 $ 137,595 Provision for credit losses 7,516 1,002 Noninterest income 55,349 51,377 Noninterest expense 131,146 128,327 Income before income taxes 49,517 59,643 Income taxes 7,982 9,343 Consolidated net income $ 41,535 $ 50,300 Selected Financial Information Total assets $ 18,376,612 $ 18,877,178 Depreciation and amortization $ 8,563 $ 7,666

Business, Basis of Financial _2

Business, Basis of Financial Statement Presentation and Principles of Consolidation - Additional Information (Details) - Fisher Brown Bottrell Insurance, Inc. [Member] - Subsequent Event [Member] $ in Millions	Apr. 23, 2024 USD ($)
Business Basis Of Financial Statement Presentation And Principles Of Consolidation [Line Items]
Proceeds from divestiture of interest in consolidated subsidiaries	$ 345
Description of transaction value represents revenue and net income	The $345.0 million transaction value represents approximately 5.9 times FBBI’s 2023 revenue and 28.0 times net income.
Proceeds from divestitures of interest in consolidated subsidiaries net of tax	$ 228

Securities Available for Sale_3

Securities Available for Sale and Held to Maturity - Amortized Cost and Estimated Fair Value of Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 1,900,980	$ 1,959,007
Securities Available for Sale, Gross Unrealized Gains	28	37
Securities Available for Sale, Gross Unrealized (Losses)	(198,709)	(196,166)
Debt Securities, Available-for-sale	1,702,299	1,762,878
Securities Held to Maturity, Amortized Cost	1,415,025	1,426,279
Securities Held to Maturity, Gross Unrealized Gains	59	51
Securities Held to Maturity, Gross Unrealized (Losses)	(82,070)	(70,826)
Securities Held to Maturity, Estimated Fair Value	1,333,014	1,355,504
U.S. Treasury Securities [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	396,289	396,179
Securities Available for Sale, Gross Unrealized Gains	0	0
Securities Available for Sale, Gross Unrealized (Losses)	(23,865)	(23,811)
Debt Securities, Available-for-sale	372,424	372,368
Securities Held to Maturity, Amortized Cost	29,261	29,068
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	(515)	(26)
Securities Held to Maturity, Estimated Fair Value	28,746	29,042
U.S. Government Agency Obligations [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	6,017	6,207
Securities Available for Sale, Gross Unrealized Gains	0	1
Securities Available for Sale, Gross Unrealized (Losses)	(423)	(416)
Debt Securities, Available-for-sale	5,594	5,792
Securities Held to Maturity, Amortized Cost	0	0
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	0	0
Securities Held to Maturity, Estimated Fair Value	0	0
Obligations of States and Political Subdivisions [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	0	0
Securities Available for Sale, Gross Unrealized Gains	0	0
Securities Available for Sale, Gross Unrealized (Losses)	0	0
Debt Securities, Available-for-sale	0	0
Securities Held to Maturity, Amortized Cost	340	340
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	0	0
Securities Held to Maturity, Estimated Fair Value	340	340
Residential Mortgage Pass-Through Securities Guaranteed by GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	25,343	25,744
Securities Available for Sale, Gross Unrealized Gains	6	4
Securities Available for Sale, Gross Unrealized (Losses)	(3,117)	(2,613)
Debt Securities, Available-for-sale	22,232	23,135
Securities Held to Maturity, Amortized Cost	18,387	13,005
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	(750)	(497)
Securities Held to Maturity, Estimated Fair Value	17,637	12,508
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	1,293,149	1,338,256
Securities Available for Sale, Gross Unrealized Gains	22	32
Securities Available for Sale, Gross Unrealized (Losses)	(163,650)	(161,490)
Debt Securities, Available-for-sale	1,129,521	1,176,798
Securities Held to Maturity, Amortized Cost	461,457	469,593
Securities Held to Maturity, Gross Unrealized Gains	46	0
Securities Held to Maturity, Gross Unrealized (Losses)	(21,935)	(18,205)
Securities Held to Maturity, Estimated Fair Value	439,568	451,388
Other Residential Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	85,317	92,076
Securities Available for Sale, Gross Unrealized Gains	0	0
Securities Available for Sale, Gross Unrealized (Losses)	(6,218)	(6,002)
Debt Securities, Available-for-sale	79,099	86,074
Securities Held to Maturity, Amortized Cost	146,447	154,466
Securities Held to Maturity, Gross Unrealized Gains	0	0
Securities Held to Maturity, Gross Unrealized (Losses)	(10,731)	(10,113)
Securities Held to Maturity, Estimated Fair Value	135,716	144,353
Commercial Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	94,865	100,545
Securities Available for Sale, Gross Unrealized Gains	0	0
Securities Available for Sale, Gross Unrealized (Losses)	(1,436)	(1,834)
Debt Securities, Available-for-sale	93,429	98,711
Securities Held to Maturity, Amortized Cost	759,133	759,807
Securities Held to Maturity, Gross Unrealized Gains	13	51
Securities Held to Maturity, Gross Unrealized (Losses)	(48,139)	(41,985)
Securities Held to Maturity, Estimated Fair Value	$ 711,007	$ 717,873

Securities Available for Sale_4

Securities Available for Sale and Held to Maturity - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Reclassification of Securities available for sale to securities held to maturity				$ 766,000,000
Net unrealized holding loss on AFS Securities at date of transfer				91,900,000
Net unrealized holding losses on AFS Securities, net of tax at date of transfer				$ 68,900,000
Net unamortized, unrealized loss on transfer of securities	$ 54,800,000		$ 57,600,000
Credit loss recognized	0		0
Potential credit loss exposure	340,000		340,000
Securities held to maturity	1,415,025,000		1,426,279,000
Gross realized losses	0	$ 0
Gross realized gains	0	$ 0
Pledged to collateralize public deposits and securities sold under repurchase agreements and for other purposes as permitted by law	2,291,000,000		2,321,000,000
Pledged securities providing additional contingency funding	0		0
30 Days or More Past Due [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities held to maturity	0		0
Securities Available for Sale [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Accrued interest receivable	3,700,000		3,700,000
Securities Held to Maturity [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Accrued interest receivable	2,700,000		2,600,000
Reserve for credit loss	0		0
Held-to-maturity nonnaccrual	$ 0		$ 0

Securities Available for Sale_5

Securities Available for Sale and Held to Maturity - Securities Held to Maturity by Credit Rating, as Determined by Moody's (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	$ 1,415,025	$ 1,426,279
Aaa [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	1,414,685	1,425,939
Not Rated [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	$ 340	$ 340

Securities Available for Sale_6

Securities Available for Sale and Held to Maturity - Securities with Gross Unrealized Losses, Segregated by Length of Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	$ 348,028	$ 349,545
Estimated Fair Value, 12 Months or More	2,677,946	2,758,879
Estimated Fair Value, Total	3,025,974	3,108,424
Gross Unrealized (Losses), Less than 12 Months	(6,870)	(3,485)
Gross Unrealized (Losses), 12 Months or More	(273,909)	(263,507)
Gross Unrealized (Losses), Total	(280,779)	(266,992)
US Treasury Securities [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	28,746	29,042
Estimated Fair Value, 12 Months or More	372,424	372,368
Estimated Fair Value, Total	401,170	401,410
Gross Unrealized (Losses), Less than 12 Months	(515)	(26)
Gross Unrealized (Losses), 12 Months or More	(23,865)	(23,811)
Gross Unrealized (Losses), Total	(24,380)	(23,837)
U.S. Government Agency Obligations [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	0	0
Estimated Fair Value, 12 Months or More	5,594	5,791
Estimated Fair Value, Total	5,594	5,791
Gross Unrealized (Losses), Less than 12 Months	0	0
Gross Unrealized (Losses), 12 Months or More	(423)	(416)
Gross Unrealized (Losses), Total	(423)	(416)
Residential Mortgage Pass-Through Securities Guaranteed by GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	14,632	9,381
Estimated Fair Value, 12 Months or More	24,950	25,967
Estimated Fair Value, Total	39,582	35,348
Gross Unrealized (Losses), Less than 12 Months	(343)	(172)
Gross Unrealized (Losses), 12 Months or More	(3,524)	(2,938)
Gross Unrealized (Losses), Total	(3,867)	(3,110)
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	303,034	309,466
Estimated Fair Value, 12 Months or More	1,259,726	1,311,865
Estimated Fair Value, Total	1,562,760	1,621,331
Gross Unrealized (Losses), Less than 12 Months	(5,957)	(3,274)
Gross Unrealized (Losses), 12 Months or More	(179,628)	(176,421)
Gross Unrealized (Losses), Total	(185,585)	(179,695)
Other Residential Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	0	0
Estimated Fair Value, 12 Months or More	214,805	230,368
Estimated Fair Value, Total	214,805	230,368
Gross Unrealized (Losses), Less than 12 Months	0	0
Gross Unrealized (Losses), 12 Months or More	(16,949)	(16,115)
Gross Unrealized (Losses), Total	(16,949)	(16,115)
Commercial Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	1,616	1,656
Estimated Fair Value, 12 Months or More	800,447	812,520
Estimated Fair Value, Total	802,063	814,176
Gross Unrealized (Losses), Less than 12 Months	(55)	(13)
Gross Unrealized (Losses), 12 Months or More	(49,520)	(43,806)
Gross Unrealized (Losses), Total	$ (49,575)	$ (43,819)

Securities Available for Sale_7

Securities Available for Sale and Held to Maturity - Contractual Maturities of Available for Sale and Held to Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Securities Available for Sale, Amortized Cost [Abstract]
Due in one year or less	$ 99,995
Due after one year through five years	296,508
Due after five years through ten years	2,236
Due after ten years	3,567
Total amortized cost, before mortgage-backed securities	402,306
Mortgage-backed securities	1,498,674
Securities Available for Sale, Amortized Cost	1,900,980	$ 1,959,007
Securities Available for Sale, Estimated Fair Value [Abstract]
Due in one year or less	98,050
Due after one year through five years	274,584
Due after five years through ten years	2,021
Due after ten years	3,363
Total fair value, before mortgage-backed securities	378,018
Mortgage-backed securities	1,324,281
Total	1,702,299	1,762,878
Securities Held to Maturity, Amortized Cost [Abstract]
Due in one year or less	340
Due after one year through five years	29,261
Due after five years through ten years	0
Due after ten years	0
Total amortized cost, before mortgage-backed securities	29,601
Mortgage-backed securities	1,385,424
Securities Held to Maturity, Amortized Cost	1,415,025	1,426,279
Securities Held to Maturity, Estimated Fair Value [Abstract]
Due in one year or less	340
Due after one year through five years	28,746
Due after five years through ten years	0
Due after ten years	0
Total fair value, before mortgage-backed securities	29,086
Mortgage-backed securities	1,303,928
Total	$ 1,333,014	$ 1,355,504

LHFI and ACL, LHFI - Loan Portf

LHFI and ACL, LHFI - Loan Portfolio Held for Investment (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Loan Portfolio [Abstract]
Total LHFI	$ 13,057,943	$ 12,950,524
Less ACL, LHFI	142,998	139,367	$ 122,239	$ 120,214
Net LHFI	12,914,945	12,811,157
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	617,008	642,886
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	625,387	622,397
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	2,266,094	2,282,318
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	1,384,610	1,312,551
Other Construction [Member] | Other Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	922,453	867,793
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	3,543,235	3,489,434
Less ACL, LHFI	33,292	24,043	18,640	19,488
Commercial and Industrial Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	1,922,711	1,922,910
Less ACL, LHFI	27,930	26,638	23,462	23,140
Consumer Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	159,340	165,734
Less ACL, LHFI	5,523	5,794	5,532	5,792
State and Other Political Subdivision Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	1,052,844	1,088,466
Less ACL, LHFI	638	646	729	885
Other Commercial Loans and Leases [Member]
Loan Portfolio [Abstract]
Total LHFI	564,261	556,035
Less ACL, LHFI	$ 6,056	$ 7,072	$ 5,710	$ 4,647

LHFI and ACL, LHFI - Additional

LHFI and ACL, LHFI - Additional Information (Details 1) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) Region	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Accrued interest receivable | $	$ 70.3	$ 71
Maximum concentration of loan as a percentage of total LHFI	10%
Key market regions | Region	5

LHFI and ACL, LHFI - Schedule o

LHFI and ACL, LHFI - Schedule of Amortized Cost Basis of Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	$ 7,158	$ 27,092
Total Nonaccrual	98,351	100,008
Loans Past Due 90 Days or More Still Accruing	5,243	5,790
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	991	2,020
Total Nonaccrual	1,809	2,642
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	923	946
Total Nonaccrual	6,843	6,518
Loans Past Due 90 Days or More Still Accruing	919	1,238
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	917	20,812
Total Nonaccrual	3,049	23,061
Loans Past Due 90 Days or More Still Accruing		54
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL		0
Total Nonaccrual	134	158
Loans Past Due 90 Days or More Still Accruing		106
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	0
Total Nonaccrual	13,098	62
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	4,291	3,235
Total Nonaccrual	48,877	43,815
Loans Past Due 90 Days or More Still Accruing	3,792	3,740
Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL	36	79
Total Nonaccrual	23,089	22,303
Loans Past Due 90 Days or More Still Accruing	49	24
Consumer Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Total Nonaccrual	238	243
Loans Past Due 90 Days or More Still Accruing	483	628
Other Commercial Loans and Leases [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Nonaccrual With No ACL		0
Total Nonaccrual	$ 1,214	$ 1,206

LHFI and ACL, LHFI - Aging Anal

LHFI and ACL, LHFI - Aging Analysis of Past Due and Nonaccrual LHFI by Loan Type (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	$ 13,057,943	$ 12,950,524
Total LHFI	13,057,943	12,950,524
30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	38,219	40,995
Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	24,249	13,898
Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	49,406	29,322
Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	111,874	84,215
Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	12,946,069	12,866,309
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	617,008	642,886
Total LHFI	617,008	642,886
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	354	93
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	590	507
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,011	2,362
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,955	2,962
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	615,053	639,924
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	625,387	622,397
Total LHFI	625,387	622,397
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	6,147	4,493
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,554	1,687
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,575	2,716
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	10,276	8,896
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	615,111	613,501
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,266,094	2,282,318
Total LHFI	2,266,094	2,282,318
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	14,706	19,298
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	7,246	9,327
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	25,361	22,164
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	47,313	50,789
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,218,781	2,231,529
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	3,543,235	3,489,434
Total LHFI	3,543,235	3,489,434
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	695	1,531
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	711	1,063
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	892	727
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,298	3,321
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	3,540,937	3,486,113
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,384,610	1,312,551
Total LHFI	1,384,610	1,312,551
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	126
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	207
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	333
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,384,610	1,312,218
Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,922,711	1,922,910
Total LHFI	1,922,711	1,922,910
Commercial and Industrial Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	12,207	11,881
Commercial and Industrial Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	446	484
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	19,018	499
Commercial and Industrial Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	31,671	12,864
Commercial and Industrial Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,891,040	1,910,046
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Total LHFI	922,453	867,793
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	62
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	13,038	0
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	13,038	62
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	909,415	867,731
Consumer Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	159,340	165,734
Total LHFI	159,340	165,734
Consumer Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,616	2,112
Consumer Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	548	772
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	512	647
Consumer Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,676	3,531
Consumer Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	156,664	162,203
State and Other Political Subdivision Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,052,844	1,088,466
Total LHFI	1,052,844	1,088,466
State and Other Political Subdivision Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	972	152
State and Other Political Subdivision Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
State and Other Political Subdivision Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
State and Other Political Subdivision Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	972	152
State and Other Political Subdivision Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,051,872	1,088,314
Other Commercial Loans and Leases [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	564,261	556,035
Total LHFI	564,261	556,035
Other Commercial Loans and Leases [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,522	1,247
Other Commercial Loans and Leases [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	116	58
Other Commercial Loans and Leases [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	37	0
Other Commercial Loans and Leases [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,675	1,305
Other Commercial Loans and Leases [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	$ 562,586	$ 554,730

LHFI and ACL, LHFI - Impact of

LHFI and ACL, LHFI - Impact of Modifications Classified as Troubled Debt Restructurings (Details) - Troubled Debt Restructurings [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable Modifications [Line Items]
Amortized Cost Basis	$ 2,274	$ 876
Post-Modification Outstanding Recorded Investment	$ 2,274	$ 876
% of Total Class of Loan	0.02%	0.01%
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Amortized Cost Basis	$ 1,461
Post-Modification Outstanding Recorded Investment	$ 1,461
% of Total Class of Loan	0.23%
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Amortized Cost Basis		$ 384
Post-Modification Outstanding Recorded Investment		$ 384
% of Total Class of Loan		0.01%
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Amortized Cost Basis	$ 813	$ 492
Post-Modification Outstanding Recorded Investment	$ 813	$ 492
% of Total Class of Loan	0.04%	0.02%

LHFI and ACL, LHFI - Troubled d

LHFI and ACL, LHFI - Troubled debt restructurings on financial effect (Details) - Troubled Debt Restructurings [Member]	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Term Extension - Financial Effect		Renewed with an extended amortization period and lowered the monthly payment amount for the borrower.
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Term Extension - Financial Effect	Extended the amortization periods on six loans by a weighted-average of 2.99 years.	Extended the amortization periods on four loans by a weighted-average of 14 years, which reduced the aggregate monthly payment amounts for the borrowers.
Weighted average amortization period	2 years 11 months 26 days	14 years
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Term Extension - Financial Effect	Modified one loan and multiple lines of credit to amortize over 24 month terms.

LHFI and ACL, LHFI - Past Due M

LHFI and ACL, LHFI - Past Due Modifications Related To Loans Held For Investment (Details) - Troubled Debt Restructurings [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable Modifications [Line Items]
Total	$ 2,274	$ 876
30 Days or More Past Due [Member]
Financing Receivable Modifications [Line Items]
Total	0	0
Past Due 60 to 89 Days [Member]
Financing Receivable Modifications [Line Items]
Total	0	0
Past Due
Financing Receivable Modifications [Line Items]
Total	0	0
Current Loans
Financing Receivable Modifications [Line Items]
Total	2,274	876
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Total	1,461
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Modifications [Line Items]
Total	0
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Modifications [Line Items]
Total	0
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due
Financing Receivable Modifications [Line Items]
Total	0
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Modifications [Line Items]
Total	1,461
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Total		384
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Modifications [Line Items]
Total		0
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Modifications [Line Items]
Total		0
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due
Financing Receivable Modifications [Line Items]
Total		0
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Modifications [Line Items]
Total		384
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Total	813	492
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Modifications [Line Items]
Total	0	0
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Modifications [Line Items]
Total		0
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due
Financing Receivable Modifications [Line Items]
Total	0	0
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Modifications [Line Items]
Total	$ 813	$ 492

LHFI and ACL, LHFI - Schedule_2

LHFI and ACL, LHFI - Schedule of Amortized Cost Basis of Collateral-Dependent Loans by Class of Loans and Collateral Type (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	$ 42,940	$ 49,082
Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	20,728	27,051
Vehicles [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	36	41
Miscellaneous [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	22,176	21,990
Construction, Land Development and Other Land [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	1,539	2,020
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	1,539	2,020
Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	923	946
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	923	946
Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	917	20,812
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	917	20,812
Other Construction Financing Receivable [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	13,038
Other Construction Financing Receivable [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	13,038
Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	4,291	3,235
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	4,291	3,235
Commercial and Industrial Loans [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	21,210	21,102
Commercial and Industrial Loans [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	20	38
Commercial and Industrial Loans [Member] | Vehicles [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	36	41
Commercial and Industrial Loans [Member] | Miscellaneous [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	21,154	21,023
Other Commercial Loans and Leases [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	1,022	967
Other Commercial Loans and Leases [Member] | Miscellaneous [Member]
Financing Receivable Impaired [Line Items]
Collateral-Dependent Loans	$ 1,022	$ 967

LHFI and ACL, LHFI - Addition_2

LHFI and ACL, LHFI - Additional Information (Details 2) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) KeyRatio	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable Recorded Investment [Line Items]
Number of days used as baseline in evaluating collateral documentation exceptions for loan policy	90 days
Number of key quality ratios | KeyRatio	6
Exposure for commercial non accrual loans to be reviewed on individual basis	$ 500
LHFS past due 90 days or more	$ 56,500		$ 51,200
Percentage of outstanding principal to be repurchased under GNMA optional repurchase program	100%
Exposure for Modified Commercial Accrual Loans Deemed To Be Reviewed On Individual Basis	$ 500
Financing Receivable [Abstract]
PCL	7,708	$ 3,244
Troubled Debt Restructurings [Member]
Financing Receivable Recorded Investment [Line Items]
Amortized Cost Basis	2,274	876
Secured by Nonfarm, Nonresidential Properties [Member] | Other Real Estate Secured [Member]
Financing Receivable [Abstract]
PCL		3,300
Other Commercial Loans and Leases Financing Receivable [Member]
Financing Receivable [Abstract]
PCL	(992)	$ 1,063
Minimum [Member]
Financing Receivable [Abstract]
Credit amount used as baseline in evaluating loan policy	$ 100

LHFI and ACL, LHFI - Summary of

LHFI and ACL, LHFI - Summary of Amortized Cost Basis of Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	$ 754,909	$ 2,557,360
Term Loans by Origination Year, Before Latest Fiscal Year	2,284,967	3,821,836
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	3,736,779	2,060,977
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	1,929,368	1,267,991
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	1,214,609	662,502
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	1,646,939	1,121,424
Financing Receivable, Revolving Loans	1,490,372	1,458,434
Total LHFI	13,057,943	12,950,524
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year	(1,544)	(6,345)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(344)	(2,951)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(695)	(4,601)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(2,755)	(313)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year	(35)	(353)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(139)	(417)
Financing Receivable, Revolving, Current Period Gross Charge-Offs	(812)	(2,535)
Total LHFI, Current Period Gross Charge-Offs	(6,324)	(17,515)
Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	49,406	29,322
Commercial and Industrial Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	1,922,711	1,922,910
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	19,018	499
State and Other Political Subdivision Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	1,052,844	1,088,466
State and Other Political Subdivision Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	0	0
Other Commercial Loans and Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	564,261	556,035
Other Commercial Loans and Leases [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	37	0
Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	159,340	165,734
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	512	647
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	617,008	642,886
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	625,387	622,397
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	1,384,610	1,312,551
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	3,543,235	3,489,434
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	892	727
Other Loans Secured by Real Estate [Member] | Other Construction [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	922,453	867,793
Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Total LHFI	2,266,094	2,282,318
Commercial LHFI [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	686,932	2,158,477
Term Loans by Origination Year, Before Latest Fiscal Year	1,914,045	2,846,360
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	2,783,676	1,503,578
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	1,386,104	1,071,603
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	1,021,452	555,406
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	1,262,837	821,512
Financing Receivable, Revolving Loans	999,156	973,511
Total LHFI	10,054,202	9,930,447
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year		(143)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(3)	(1,362)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(253)	(4,208)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(2,706)	(164)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year	(8)	(342)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(131)	(252)
Financing Receivable, Revolving, Current Period Gross Charge-Offs		(7)
Total LHFI, Current Period Gross Charge-Offs	(3,101)	(6,478)
Commercial LHFI [Member] | Commercial and Industrial Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	190,849	515,103
Term Loans by Origination Year, Before Latest Fiscal Year	476,164	501,808
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	393,603	175,718
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	140,561	93,985
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	70,980	32,026
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	71,756	45,077
Financing Receivable, Revolving Loans	578,798	559,193
Total LHFI	1,922,711	1,922,910
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year		(42)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(3)	(1,071)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(225)	(700)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(294)	(138)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year	(8)	(95)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(54)	(108)
Financing Receivable, Revolving, Current Period Gross Charge-Offs		(7)
Total LHFI, Current Period Gross Charge-Offs	(584)	(2,161)
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	188,609	497,730
Term Loans by Origination Year, Before Latest Fiscal Year	459,063	474,737
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	323,119	158,659
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	124,545	80,646
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	58,584	31,876
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	70,060	44,972
Financing Receivable, Revolving Loans	538,649	537,527
Total LHFI	1,762,629	1,826,147
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		12,570
Term Loans by Origination Year, Before Latest Fiscal Year	12,270	10,141
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	22,693	3,149
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	2,136	1,381
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	554	110
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	1,323
Financing Receivable, Revolving Loans	20,264	126
Total LHFI	59,240	27,477
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	2,240	4,797
Term Loans by Origination Year, Before Latest Fiscal Year	4,831	16,872
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	47,455	13,909
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	13,725	11,958
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	11,842	40
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	350	80
Financing Receivable, Revolving Loans	19,884	21,528
Total LHFI	100,327	69,184
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Doubtful - RR 9 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		6
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	336	1
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	155
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	23	25
Financing Receivable, Revolving Loans	1	12
Total LHFI	515	102
Commercial LHFI [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	16,902	152,157
Term Loans by Origination Year, Before Latest Fiscal Year	122,135	247,034
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	243,470	174,812
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	168,190	99,786
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	96,337	32,118
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	401,066	377,225
Financing Receivable, Revolving Loans	4,744	5,334
Total LHFI	1,052,844	1,088,466
Commercial LHFI [Member] | State and Other Political Subdivision Loans [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	16,902	152,157
Term Loans by Origination Year, Before Latest Fiscal Year	122,135	247,034
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	243,470	174,812
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	168,190	99,786
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	96,337	32,118
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	401,066	377,225
Financing Receivable, Revolving Loans	4,744	5,334
Total LHFI	1,052,844	1,088,466
Commercial LHFI [Member] | Other Commercial Loans and Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	45,328	211,508
Term Loans by Origination Year, Before Latest Fiscal Year	193,657	49,158
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	23,883	30,113
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	26,816	21,585
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	19,070	32,837
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	40,003	8,488
Financing Receivable, Revolving Loans	215,504	202,346
Total LHFI	564,261	556,035
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year		(40)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year		(248)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(28)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year		(26)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(25)
Total LHFI, Current Period Gross Charge-Offs	(53)	(314)
Commercial LHFI [Member] | Other Commercial Loans and Leases [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	44,336	211,402
Term Loans by Origination Year, Before Latest Fiscal Year	193,567	48,947
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	23,760	30,071
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	26,671	21,377
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	18,877	32,837
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	40,003	8,468
Financing Receivable, Revolving Loans	214,044	201,339
Total LHFI	561,258	554,441
Commercial LHFI [Member] | Other Commercial Loans and Leases [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	120	208
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	193
Financing Receivable, Revolving Loans		20
Total LHFI	313	228
Commercial LHFI [Member] | Other Commercial Loans and Leases [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	992	106
Term Loans by Origination Year, Before Latest Fiscal Year	90	211
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	123	42
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	25
Financing Receivable, Revolving Loans	1,460	987
Total LHFI	2,690	1,346
Commercial LHFI [Member] | Other Commercial Loans and Leases [Member] | Doubtful - RR 9 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year		20
Total LHFI		20
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	98,031	360,419
Term Loans by Origination Year, Before Latest Fiscal Year	268,333	99,078
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	78,090	36,967
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	31,648	10,610
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	10,245	2,036
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	3,444	2,006
Financing Receivable, Revolving Loans	49,281	52,351
Total LHFI	539,072	563,467
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year		(4)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year		(10)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year		(228)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(24)
Total LHFI, Current Period Gross Charge-Offs	(24)	(242)
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	98,031	359,813
Term Loans by Origination Year, Before Latest Fiscal Year	268,068	98,742
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	77,825	35,095
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	30,055	10,591
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	10,227	2,036
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	3,425	1,961
Financing Receivable, Revolving Loans	49,281	52,351
Total LHFI	536,912	560,589
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Two Years Before Latest Fiscal Year		360
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	354
Total LHFI	354	360
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		606
Term Loans by Origination Year, Before Latest Fiscal Year	265	336
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	265	1,512
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	1,239	19
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	18
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	19	21
Total LHFI	1,806	2,494
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Doubtful - RR 9 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year		24
Total LHFI		24
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	6,466	33,292
Term Loans by Origination Year, Before Latest Fiscal Year	32,546	31,467
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	29,272	29,364
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	26,140	14,341
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	13,476	8,164
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	9,450	3,128
Financing Receivable, Revolving Loans	7,923	10,175
Total LHFI	125,273	129,931
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year		(24)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(12)	(6)
Total LHFI, Current Period Gross Charge-Offs	(12)	(30)
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	6,379	33,072
Term Loans by Origination Year, Before Latest Fiscal Year	32,381	30,760
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	28,573	29,159
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	25,941	14,309
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	13,447	8,084
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	9,086	2,822
Financing Receivable, Revolving Loans	7,889	10,077
Total LHFI	123,696	128,283
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	28
Term Loans by Origination Year, Before Latest Fiscal Year		82
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	53	48
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	44
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	8
Total LHFI	133	140
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	59	220
Term Loans by Origination Year, Before Latest Fiscal Year	165	625
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	646	157
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	155	22
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	21	80
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	364	306
Financing Receivable, Revolving Loans	34	98
Total LHFI	1,444	1,508
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	117,080	194,309
Term Loans by Origination Year, Before Latest Fiscal Year	114,609	463,340
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	542,402	332,818
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	309,852	210,047
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	209,560	91,905
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	82,097	11,119
Financing Receivable, Revolving Loans	8,758	8,880
Total LHFI	1,384,358	1,312,418
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	116,981	194,141
Term Loans by Origination Year, Before Latest Fiscal Year	114,564	447,200
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	539,374	332,818
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	309,788	209,757
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	209,292	56,024
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	46,190	11,080
Financing Receivable, Revolving Loans	8,758	8,880
Total LHFI	1,344,947	1,259,900
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		126
Term Loans by Origination Year, Before Latest Fiscal Year		2,076
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	64
Term Loans by Origination Year, Four Years Before Latest Fiscal Year		35,881
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	35,876
Total LHFI	35,940	38,083
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	99
Term Loans by Origination Year, Before Latest Fiscal Year		14,064
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	3,028
Term Loans by Origination Year, Three Years Before Latest Fiscal Year		290
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	268
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	31	39
Total LHFI	3,426	14,393
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Doubtful - RR 9 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		42
Term Loans by Origination Year, Before Latest Fiscal Year	45
Total LHFI	45	42
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	171,852	511,951
Term Loans by Origination Year, Before Latest Fiscal Year	498,360	936,413
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	965,679	573,903
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	532,903	607,187
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	585,607	356,320
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	655,021	374,463
Financing Receivable, Revolving Loans	133,808	129,190
Total LHFI	3,543,230	3,489,427
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year		(39)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year		(82)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(2,412)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year		(19)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(16)	(138)
Total LHFI, Current Period Gross Charge-Offs	(2,428)	(278)
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	167,040	501,327
Term Loans by Origination Year, Before Latest Fiscal Year	492,579	919,519
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	944,333	526,412
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	505,580	596,240
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	574,763	323,687
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	616,719	369,250
Financing Receivable, Revolving Loans	132,679	129,142
Total LHFI	3,433,693	3,365,577
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Special Mention - RR 7 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		4,271
Term Loans by Origination Year, Before Latest Fiscal Year	4,260	14,930
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	19,546
Term Loans by Origination Year, Three Years Before Latest Fiscal Year		138
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	133	23,966
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	24,979
Total LHFI	48,918	43,305
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	4,794	6,332
Term Loans by Origination Year, Before Latest Fiscal Year	1,521	1,964
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	1,800	47,491
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	27,323	10,809
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	10,711	8,614
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	13,266	5,200
Financing Receivable, Revolving Loans	1,129	48
Total LHFI	60,544	80,458
Commercial LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Doubtful - RR 9 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	18	21
Term Loans by Origination Year, Four Years Before Latest Fiscal Year		53
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	57	13
Total LHFI	75	87
Commercial LHFI [Member] | Other Loans Secured by Real Estate [Member] | Other Construction [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	40,424	179,738
Term Loans by Origination Year, Before Latest Fiscal Year	208,241	518,062
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	507,277	149,883
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	149,994	14,062
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	16,177
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year		6
Financing Receivable, Revolving Loans	340	6,042
Total LHFI	922,453	867,793
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year		(61)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year		(3,392)
Total LHFI, Current Period Gross Charge-Offs		(3,453)
Commercial LHFI [Member] | Other Loans Secured by Real Estate [Member] | Other Construction [Member] | Pass - RR 1 through RR 6 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	40,364	179,676
Term Loans by Origination Year, Before Latest Fiscal Year	208,241	518,062
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	494,239	149,883
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	149,994	14,062
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	16,177
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year		6
Financing Receivable, Revolving Loans	340	6,042
Total LHFI	909,355	867,731
Commercial LHFI [Member] | Other Loans Secured by Real Estate [Member] | Other Construction [Member] | Substandard - RR 8 [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	60	62
Term Loans by Origination Year, Before Latest Fiscal Year
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	13,038
Term Loans by Origination Year, Three Years Before Latest Fiscal Year
Term Loans by Origination Year, Four Years Before Latest Fiscal Year
Financing Receivable, Revolving Loans
Total LHFI	13,098	62
Consumer LHFI [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	67,977	398,883
Term Loans by Origination Year, Before Latest Fiscal Year	370,922	975,476
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	953,103	557,399
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	543,264	196,388
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	193,157	107,096
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	384,102	299,912
Financing Receivable, Revolving Loans	491,216	484,923
Total LHFI	3,003,741	3,020,077
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year	(1,544)	(6,202)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(341)	(1,589)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(442)	(393)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(49)	(149)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year	(27)	(11)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(8)	(165)
Financing Receivable, Revolving, Current Period Gross Charge-Offs	(812)	(2,528)
Total LHFI, Current Period Gross Charge-Offs	(3,223)	(11,037)
Consumer LHFI [Member] | Consumer Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	21,363	60,878
Term Loans by Origination Year, Before Latest Fiscal Year	44,622	33,351
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	26,611	10,919
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	8,773	2,665
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	2,126	922
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	845	299
Financing Receivable, Revolving Loans	55,000	56,700
Total LHFI	159,340	165,734
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year	(1,544)	(6,138)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(282)	(559)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(122)	(167)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(20)	(43)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year	(27)	(1)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year		(1)
Financing Receivable, Revolving, Current Period Gross Charge-Offs	(753)	(2,381)
Total LHFI, Current Period Gross Charge-Offs	(2,748)	(9,290)
Consumer LHFI [Member] | Consumer Loans [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	20,996	59,496
Term Loans by Origination Year, Before Latest Fiscal Year	43,982	32,767
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	26,201	10,698
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	8,570	2,604
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	2,098	917
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	840	294
Financing Receivable, Revolving Loans	53,867	55,321
Total LHFI	156,554	162,097
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 30-89 Days [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	348	1,274
Term Loans by Origination Year, Before Latest Fiscal Year	518	475
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	288	134
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	122	34
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	1	5
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	5	5
Financing Receivable, Revolving Loans	784	839
Total LHFI	2,066	2,766
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	19	64
Term Loans by Origination Year, Before Latest Fiscal Year	58	44
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	66	3
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	4	1
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	8
Financing Receivable, Revolving Loans	328	516
Total LHFI	483	628
Consumer LHFI [Member] | Consumer Loans [Member] | Nonaccrual [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		44
Term Loans by Origination Year, Before Latest Fiscal Year	64	65
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	56	84
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	77	26
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	19
Financing Receivable, Revolving Loans	21	24
Total LHFI	237	243
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	4,808	44,912
Term Loans by Origination Year, Before Latest Fiscal Year	46,952	23,360
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	15,604	6,121
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5,306	1,203
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	1,165	1,112
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	2,539	2,058
Financing Receivable, Revolving Loans	1,562	653
Total LHFI	77,936	79,419
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	4,808	44,912
Term Loans by Origination Year, Before Latest Fiscal Year	46,918	23,110
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	15,604	5,973
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5,300	1,203
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	1,165	1,082
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	2,497	1,864
Financing Receivable, Revolving Loans	1,562	653
Total LHFI	77,854	78,797
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Past Due 30-89 Days [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Before Latest Fiscal Year	34	250
Term Loans by Origination Year, Four Years Before Latest Fiscal Year		30
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	39	191
Total LHFI	73	471
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Nonaccrual [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Two Years Before Latest Fiscal Year		148
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	6
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	3	3
Total LHFI	9	151
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	8,491	29,869
Term Loans by Origination Year, Before Latest Fiscal Year	24,821	11,774
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	10,405	5,855
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5,697	4,483
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	4,372	4,364
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	11,674	8,551
Financing Receivable, Revolving Loans	434,654	427,570
Total LHFI	500,114	492,466
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year		(100)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(5)	(9)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year		(2)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Four Years Before Latest Fiscal Year		(10)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year		(22)
Financing Receivable, Revolving, Current Period Gross Charge-Offs	(59)	(147)
Total LHFI, Current Period Gross Charge-Offs	(64)	(290)
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	8,491	29,636
Term Loans by Origination Year, Before Latest Fiscal Year	24,784	11,366
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	10,059	5,733
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5,482	4,471
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	4,202	4,313
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	10,754	7,674
Financing Receivable, Revolving Loans	424,148	417,383
Total LHFI	487,920	480,576
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Past Due 30-89 Days [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		225
Term Loans by Origination Year, Before Latest Fiscal Year	30	68
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	254	74
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	169	4
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	60	51
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	286	220
Financing Receivable, Revolving Loans	4,451	4,292
Total LHFI	5,250	4,934
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Before Latest Fiscal Year		264
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	5
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	100
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	48	41
Financing Receivable, Revolving Loans	684	934
Total LHFI	837	1,239
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Nonaccrual [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		8
Term Loans by Origination Year, Before Latest Fiscal Year	7	76
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	87	48
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	46	8
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	10
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	586	616
Financing Receivable, Revolving Loans	5,371	4,961
Total LHFI	6,107	5,717
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	131
Term Loans by Origination Year, Three Years Before Latest Fiscal Year		78
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	75
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	46	55
Total LHFI	252	133
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	131
Term Loans by Origination Year, Three Years Before Latest Fiscal Year		78
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	75
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	46	55
Total LHFI	252	133
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Two Years Before Latest Fiscal Year		7
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5
Total LHFI	5	7
Consumer LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Two Years Before Latest Fiscal Year		7
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	5
Total LHFI	5	7
Consumer LHFI [Member] | Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	33,184	263,224
Term Loans by Origination Year, Before Latest Fiscal Year	254,527	906,991
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	900,483	534,497
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	523,483	187,959
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	185,419	100,698
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	368,998	288,949
Total LHFI	2,266,094	2,282,318
Term Loans by Origination Year, Current Period Gross Charge-Offs, Current Fiscal Year		(64)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Before Latest Fiscal Year	(59)	(930)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Two Years Before Latest Fiscal Year	(315)	(217)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Three Years Before Latest Fiscal Year	(29)	(104)
Term Loans by Origination Year, Current Period Gross Charge-Offs, Five or More Years Before Latest Fiscal Year	(8)	(142)
Total LHFI, Current Period Gross Charge-Offs	(411)	(1,457)
Consumer LHFI [Member] | Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Current [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year	33,184	258,800
Term Loans by Origination Year, Before Latest Fiscal Year	249,825	878,893
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	871,791	516,324
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	506,872	180,272
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	178,382	98,552
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	355,532	277,664
Total LHFI	2,195,586	2,210,505
Consumer LHFI [Member] | Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Past Due 30-89 Days [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		3,370
Term Loans by Origination Year, Before Latest Fiscal Year	2,410	11,293
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	9,575	5,513
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	2,777	2,121
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	830	298
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	2,246	1,664
Total LHFI	17,838	24,259
Consumer LHFI [Member] | Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Past Due 90 Days or More [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		376
Term Loans by Origination Year, Before Latest Fiscal Year	527	1,219
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	1,175	1,208
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	1,052	682
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	127
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	911	255
Total LHFI	3,792	3,740
Consumer LHFI [Member] | Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Nonaccrual [Member]
Financing Receivable Recorded Investment [Line Items]
Term Loans by Origination Year, Current Fiscal Year		678
Term Loans by Origination Year, Before Latest Fiscal Year	1,765	15,586
Term Loans by Origination Year, Two Years Before Latest Fiscal Year	17,942	11,452
Term Loans by Origination Year, Three Years Before Latest Fiscal Year	12,782	4,884
Term Loans by Origination Year, Four Years Before Latest Fiscal Year	6,080	1,848
Term Loans by Origination Year, Five or More Years Before Latest Fiscal Year	10,309	9,366
Total LHFI	$ 48,878	$ 43,814

LHFI and ACL, LHFI - Summary _2

LHFI and ACL, LHFI - Summary of Trustmark's Portfolio Segments, Loan Classes, Loan Pools and the ACL Methodology and Loss Drivers (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | 1 -4 Family Residential Construction [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Prime Rate, National GDP
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Lots and Development [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Prime Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Unimproved Land [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Prime Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | All Other Consumer [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Southern Unemployment
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | All Other Consumer [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Southern Unemployment
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Consumer 1-4 Family - 1st Liens [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Prime Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Nonresidential Owner- Occupied [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Southern Unemployment, National CRE Price Index	Southern Unemployment, National GDP
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonresidential Owner- Occupied [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Southern Unemployment, National CRE Price Index	Southern Unemployment, National GDP
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied - Hotel/Motel [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied - Office [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied- Retail [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied- Senior Living/ Nursing Homes [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-occupied - All Other [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonresidential Owner- Occupied [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Southern Unemployment, National CRE Price Index	Southern Unemployment, National GDP
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonowner-occupied - All Other [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonresidential Nonowner- Occupied - Apartments [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, Southern Unemployment	Southern Vacancy Rate, Southern Unemployment
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Commercial and Industrial - Non-Working Capital [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Trustmark historical data	Trustmark historical data
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Commercial and Industrial - Working Capital [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Trustmark historical data	Trustmark historical data
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Equipment Finance Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	WARM	WARM
Loss Drivers	Southern Unemployment, National GDP	Southern Unemployment, Southern GDP
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Credit Cards [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	WARM	WARM
Loss Drivers	Trustmark call report data	Trustmark call report data
Other Loans Secured by Real Estate [Member] | Other Construction [Member] | Other Construction [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National CRE Price Index, National Unemployment, BBB 7-10 US CBI	Prime Rate, National Unemployment
Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Trustmark Mortgage [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	WARM	WARM
Loss Drivers	Southern Unemployment	Southern Unemployment
Consumer Loans [Member] | Consumer Loans [Member] | All Other Consumer [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	National HPI, National Unemployment	Southern Unemployment
Consumer Loans [Member] | Consumer Loans [Member] | Credit Cards [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	WARM	WARM
Loss Drivers	Trustmark call report data	Trustmark call report data
Consumer Loans [Member] | Consumer Loans [Member] | Overdrafts [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	Loss Rate	Loss Rate
Loss Drivers	Trustmark historical data	Trustmark historical data
State and Other Political Subdivision Loans [Member] | State and Other Political Subdivision Loans [Member] | Obligations of State and Political Subdivisions [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Moody's Bond Default Study	Moody's Bond Default Study
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Commercial and Industrial - Non-Working Capital [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Trustmark historical data	Trustmark historical data
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Commercial and Industrial - Working Capital [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	Trustmark historical data	Trustmark historical data
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Equipment Finance Leases [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	WARM	WARM
Loss Drivers	Southern Unemployment, National GDP	Southern Unemployment, Southern GDP
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Other Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Methodology	DCF	DCF
Loss Drivers	BBB 7-10 US CBI, Southern Unemployment	Prime Rate, Southern Unemployment

LHFI and ACL, LHFI - Summary _3

LHFI and ACL, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	$ 12,620	$ 12,403
Individually Evaluated for Credit Loss	42,940	49,082
Collectively Evaluated for Credit Loss	130,378	126,964
Collectively Evaluated for Credit Loss	13,015,003	12,901,442
Total LHFI	13,057,943	12,950,524
Total	142,998	139,367	$ 122,239	$ 120,214
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	10,960	11,436
Individually Evaluated for Credit Loss	21,210	21,102
Collectively Evaluated for Credit Loss	16,970	15,202
Collectively Evaluated for Credit Loss	1,901,501	1,901,808
Total LHFI	1,922,711	1,922,910
Total	27,930	26,638	23,462	23,140
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively Evaluated for Credit Loss	5,523	5,794
Collectively Evaluated for Credit Loss	159,340	165,734
Total LHFI	159,340	165,734
Total	5,523	5,794	5,532	5,792
State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	0
Individually Evaluated for Credit Loss	0	0
Collectively Evaluated for Credit Loss	638	646
Collectively Evaluated for Credit Loss	1,052,844	1,088,466
Total LHFI	1,052,844	1,088,466
Total	638	646	729	885
Other Commercial Loans and Leases [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	1,022	967
Individually Evaluated for Credit Loss	1,022	967
Collectively Evaluated for Credit Loss	5,034	6,105
Collectively Evaluated for Credit Loss	563,239	555,068
Total LHFI	564,261	556,035
Total	6,056	7,072	5,710	4,647
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	12	0
Individually Evaluated for Credit Loss	1,539	2,020
Collectively Evaluated for Credit Loss	5,731	17,192
Collectively Evaluated for Credit Loss	615,469	640,866
Total LHFI	617,008	642,886
Total	5,743	17,192	13,260	12,828
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	923	946
Collectively Evaluated for Credit Loss	10,554	12,942
Collectively Evaluated for Credit Loss	624,464	621,451
Total LHFI	625,387	622,397
Total	10,554	12,942	11,918	12,374
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	917	20,812
Collectively Evaluated for Credit Loss	33,292	24,043
Collectively Evaluated for Credit Loss	3,542,318	3,468,622
Total LHFI	3,543,235	3,489,434
Total	33,292	24,043	18,640	19,488
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	0
Collectively Evaluated for Credit Loss	9,251	4,488
Collectively Evaluated for Credit Loss	1,384,610	1,312,551
Total LHFI	1,384,610	1,312,551
Total	9,251	4,488	2,362	4,743
Other Loans Secured by Real Estate [Member] | Other Construction [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	626	0
Individually Evaluated for Credit Loss	13,038	0
Collectively Evaluated for Credit Loss	11,439	5,758
Collectively Evaluated for Credit Loss	909,415	867,793
Total LHFI	922,453	867,793
Total	12,065	5,758	14,470	15,132
Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	4,291	3,235
Collectively Evaluated for Credit Loss	31,946	34,794
Collectively Evaluated for Credit Loss	2,261,803	2,279,083
Total LHFI	2,266,094	2,282,318
Total	$ 31,946	$ 34,794	$ 26,156	$ 21,185

LHFI and ACL, LHFI - Change in

LHFI and ACL, LHFI - Change in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 139,367	$ 120,214
Loans charged-off	(6,324)	(2,996)
Recoveries	2,247	1,777
Net (charge-offs) recoveries	(4,077)	(1,219)
Provision for credit losses (PCL), LHFI	7,708	3,244
Balance at end of period	142,998	122,239
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	26,638	23,140
Loans charged-off	(584)	(471)
Recoveries	198	270
Provision for credit losses (PCL), LHFI	1,678	523
Balance at end of period	27,930	23,462
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	5,794	5,792
Loans charged-off	(2,748)	(2,155)
Recoveries	1,505	1,317
Provision for credit losses (PCL), LHFI	972	578
Balance at end of period	5,523	5,532
State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	646	885
Loans charged-off	0
Recoveries	0
Provision for credit losses (PCL), LHFI	(8)	(156)
Balance at end of period	638	729
Other Commercial Loans and Leases [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	7,072	4,647
Loans charged-off	(53)	0
Recoveries	29	0
Provision for credit losses (PCL), LHFI	(992)	1,063
Balance at end of period	6,056	5,710
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	17,192	12,828
Loans charged-off	(24)	(14)
Recoveries	1	8
Provision for credit losses (PCL), LHFI	(11,426)	438
Balance at end of period	5,743	13,260
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	12,942	12,374
Loans charged-off	(76)	(34)
Recoveries	450	47
Provision for credit losses (PCL), LHFI	(2,762)	(469)
Balance at end of period	10,554	11,918
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	24,043	19,488
Loans charged-off	(2,428)	(28)
Recoveries	9	96
Provision for credit losses (PCL), LHFI	11,668	(916)
Balance at end of period	33,292	18,640
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	4,488	4,743
Loans charged-off	0	0
Recoveries	0	3
Provision for credit losses (PCL), LHFI	4,763	(2,384)
Balance at end of period	9,251	2,362
Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	34,794	21,185
Loans charged-off	(411)	(294)
Recoveries	38	6
Provision for credit losses (PCL), LHFI	(2,475)	5,259
Balance at end of period	31,946	26,156
Other Loans Secured by Real Estate [Member] | Other Construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	5,758	15,132
Loans charged-off	0	0
Recoveries	17	30
Provision for credit losses (PCL), LHFI	6,290	(692)
Balance at end of period	$ 12,065	$ 14,470

Mortgage Banking - Schedule of

Mortgage Banking - Schedule of Activity in the Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Mortgage servicing rights [Abstract]
Balance at beginning of period	$ 131,870	$ 129,677
Origination of servicing assets	2,977	2,646
Change in fair value [Abstract]
Due to market changes	$ 5,123	$ (3,972)
Servicing Asset, Fair Value, Change in Fair Value, Valuation Input, Statement of Income or Comprehensive Income [Extensible Enumeration]	Mortgage Banking Income	Mortgage Banking Income
Due to run-off	$ (1,926)	$ (1,145)
Balance at end of period	$ 138,044	$ 127,206

Mortgage Banking - Additional I

Mortgage Banking - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) CPR	Mar. 31, 2023 USD ($) CPR
Mortgage servicing rights [Abstract]
Assumed average prepayment speed | CPR	8	8
Average discount rate	10.08%	10.08%
Residential mortgage loans sold	$ 258,300	$ 213,800
Period of putback response	60 days
Reserve for mortgage loan servicing putback expenses	$ 500	500
Gains on sale of mortgage banking	$ 5,000	$ 3,800

Mortgage Banking - Schedule o_2

Mortgage Banking - Schedule of Mortgage Loans Sold and Serviced for Others (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	$ 8,553,234	$ 8,477,375
Federal National Mortgage Association [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	4,831,183	4,826,028
Government National Mortgage Association [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	3,557,236	3,510,983
Federal Home Loan Mortgage Corporation [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	137,725	112,352
Other [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	$ 27,090	$ 28,012

Other Real Estate - Changes and

Other Real Estate - Changes and Gains (Losses), Net on Other Real Estate (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Balance at beginning of period	$ 6,867	$ 1,986
Additions	2,228	300
Disposals	(957)	(542)
(Write-downs) recoveries	(518)	(60)
Balance at end of period	7,620	1,684
Gains (losses), net on the sale of other real estate included in other real estate expense	$ (55)	$ (77)

Other Real Estate - Other Real

Other Real Estate - Other Real Estate, by Type of Property (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Other real estate [Line Items]
Total other real estate	$ 7,620	$ 6,867	$ 1,684	$ 1,986
1 - 4 Family Residential Properties [Member]
Other real estate [Line Items]
Total other real estate	3,619	1,977
Nonfarm, Nonresidential Properties [Member]
Other real estate [Line Items]
Total other real estate	3,946	4,835
Other Real Estate Properties [Member]
Other real estate [Line Items]
Total other real estate	$ 55	$ 55

Other Real Estate - Other Rea_2

Other Real Estate - Other Real Estate, by Geographic Location (Details) - USD ($)		Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Other Real Estate by Geographic Location [Line Items]
Total other real estate		$ 7,620,000	$ 6,867,000	$ 1,684,000	$ 1,986,000
Alabama [Member]
Other Real Estate by Geographic Location [Line Items]
Total other real estate		1,050,000	1,397,000
Florida [Member]
Other Real Estate by Geographic Location [Line Items]
Total other real estate		71,000	0
Mississippi [Member]
Other Real Estate by Geographic Location [Line Items]
Total other real estate	[1]	2,870,000	1,242,000
Tennessee [Member]
Other Real Estate by Geographic Location [Line Items]
Total other real estate	[2]	86,000	0
Texas [Member]
Other Real Estate by Geographic Location [Line Items]
Total other real estate		$ 3,543,000	$ 4,228,000
[1] Mississippi includes Central and Southern Mississippi Regions. Tennessee includes Memphis, Tennessee and Northern Mississippi Regions.

Other Real Estate - Additional

Other Real Estate - Additional information (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Foreclosed residential real estate properties recorded as a result of obtaining physical possession of property	$ 3.6	$ 2
Consumer mortgage loans and that formal foreclosure proceedings are in process	$ 9.8	$ 6.4

Leases - Additional Information

Leases - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Lessee, Lease, Description [Line Items]
Interest Income from its Sales-Type and Direct Financing Leases	$ 2.4
Minimum [Member]
Lessee, Lease, Description [Line Items]
Remaining Lease Term	2 years
Maximum [Member]
Lessee, Lease, Description [Line Items]
Remaining Lease Term	9 years

Leases - Components of the Trus

Leases - Components of the Trustmark's Net Investment in its Sales-Type and Direct Financing Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Leases receivable	$ 202,112	$ 161,319
Unearned income	(35,463)	(29,011)
Initial direct costs	1,737	1,326
Unguaranteed lease residual	5,577	4,101
Total net investment	$ 173,963	$ 137,735

Leases - Minimum Future Lease P

Leases - Minimum Future Lease Payments for Trustmark's Leases Receivable (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Sales-Type and Direct Financing Leases, Payment to be Received, Fiscal Year Maturity [Abstract]
2024 (excluding the three months ended March 31, 2024)	$ 24,711
2025	33,074
2026	31,972
2027	44,528
2028	28,216
Thereafter	39,611
Lease receivable	$ 202,112

Leases - Components of Net Leas

Leases - Components of Net Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Finance leases:
Amortization of right-of-use assets	$ 113	$ 357
Interest on lease liabilities	38	42
Operating lease cost	1,294	1,285
Short-term lease cost	21	89
Variable lease cost	215	255
Sublease income	(3)	(3)
Net lease cost	$ 1,678	$ 2,025

Leases - Cash Payments Included

Leases - Cash Payments Included in Measurement of Lease Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Finance leases:
Operating cash flows included in operating activities	$ 38	$ 42
Financing cash flows included in payments under finance lease obligations	99	342
Operating leases:
Operating cash flows (fixed payments) included in other operating activities, net	1,212	1,242
Operating cash flows (liability reduction) included in other operating activities, net	$ 865	$ 944

Leases - Balance Sheet Informat

Leases - Balance Sheet Information and Weighted-Average Lease Terms and Discount Rates Related to Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Finance lease right-of-use assets, net of accumulated depreciation	$ 3,638	$ 3,751
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Finance lease liabilities	$ 4,234	$ 4,334
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Borrowings	Other Borrowings
Operating lease right-of-use assets	$ 36,659	$ 38,142
Operating lease liabilities	$ 40,185	$ 41,584
Weighted-average lease term:
Finance leases	8 years 1 month 2 days	8 years 4 months 2 days
Operating leases	10 years	10 years 1 month 17 days
Weighted-average discount rate:
Finance leases	3.61%	3.61%
Operating leases	3.64%	3.64%

Leases - Future Minimum Rental

Leases - Future Minimum Rental Commitments Under Finance and Operating Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Finance leases, 2024 (excluding the three months ended March 31, 2024)	$ 435
Finance leases, 2025	584
Finance leases, 2026	589
Finance leases, 2027	594
Finance leases, 2028	599
Finance Lease Thereafter	2,086
Finance leases, total minimum lease payments	4,887
Finance leases, imputed interest	(653)
Finance lease liabilities	4,234	$ 4,334
Operating leases, 2024 (excluding the three months ended March 31, 2024)	3,718
Operating leases 2025	4,998
Operating leases, 2026	4,846
Operating leases, 2027	4,900
Operating leases, 2028	4,749
Operating leases, Thereafter	25,452
Operating leases, total minimum lease payments	48,663
Operating leases, imputed interest	(8,478)
Operating lease liabilities	$ 40,185	$ 41,584

Deposits - Deposits Summary (De

Deposits - Deposits Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Deposits [Abstract]
Noninterest-bearing demand	$ 3,039,652	$ 3,197,620
Interest-bearing demand	5,226,089	4,947,626
Savings	3,750,392	4,047,853
Time	3,322,424	3,376,664
Total deposits	$ 15,338,557	$ 15,569,763

Securities Sold Under Repurch_3

Securities Sold Under Repurchase Agreement - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Disclosure [Abstract]
Securities sold under repurchase agreements, secured by securities carrying amount	$ 59.4	$ 61.6

Securities Sold Under Repurch_4

Securities Sold Under Repurchase Agreements - Schedule of Securities Sold Under Repurchase Agreements (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Securities sold under repurchase agreements by collateral pledged
Total securities sold under repurchase agreements	$ 39,722	$ 29,126
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member]
Securities sold under repurchase agreements by collateral pledged
Total securities sold under repurchase agreements	39,437	28,600
Other Residential Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]
Securities sold under repurchase agreements by collateral pledged
Total securities sold under repurchase agreements	$ 285	$ 526

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Other real estate sales, net gains (losses)	$ (55)	$ (78)

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Summary of Noninterest Income Disaggregated by Reportable Operating Segment and Revenue Stream (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		$ 10,958	$ 10,336
Bank card and other fees		7,428	7,803
Mortgage banking, net		8,915	7,639
Insurance commissions		15,464	14,305
Wealth management		8,952	8,780
Other, net		3,632	2,514
Total Noninterest Income		55,349	51,377
Topic 606 [Member]
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		10,958	10,336
Bank card and other fees		7,228	7,654
Insurance commissions		15,464	14,305
Wealth management		8,952	8,780
Other, net		3,920	3,027
Total Noninterest Income		46,522	44,102
Not Topic 606 [Member
Revenue From Contract With Customer [Line Items]
Bank card and other fees	[1]	200	149
Mortgage banking, net	[1]	8,915	7,639
Other, net	[1]	(288)	(513)
Total Noninterest Income	[1]	8,827	7,275
General Banking Segment [Member]
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		10,936	10,315
Bank card and other fees		7,392	7,792
Mortgage banking, net		8,915	7,639
Wealth management		189	233
Other, net		2,966	2,380
Total Noninterest Income		30,398	28,359
General Banking Segment [Member] | Topic 606 [Member]
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		10,936	10,315
Bank card and other fees		7,192	7,643
Wealth management		189	233
Other, net		3,348	2,988
Total Noninterest Income		21,665	21,179
General Banking Segment [Member] | Not Topic 606 [Member
Revenue From Contract With Customer [Line Items]
Bank card and other fees	[1]	200	149
Mortgage banking, net	[1]	8,915	7,639
Other, net	[1]	(382)	(608)
Total Noninterest Income	[1]	8,733	7,180
Wealth Management Segment [Member]
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		22	21
Bank card and other fees		36	11
Wealth management		8,763	8,547
Other, net		136	140
Total Noninterest Income		8,957	8,719
Wealth Management Segment [Member] | Topic 606 [Member]
Revenue From Contract With Customer [Line Items]
Service charges on deposit accounts		22	21
Bank card and other fees		36	11
Wealth management		8,763	8,547
Other, net		42	45
Total Noninterest Income		8,863	8,624
Wealth Management Segment [Member] | Not Topic 606 [Member
Revenue From Contract With Customer [Line Items]
Other, net	[1]	94	95
Total Noninterest Income	[1]	94	95
Insurance Segment [Member]
Revenue From Contract With Customer [Line Items]
Insurance commissions		15,464	14,305
Other, net		530	(6)
Total Noninterest Income		15,994	14,299
Insurance Segment [Member] | Topic 606 [Member]
Revenue From Contract With Customer [Line Items]
Insurance commissions		15,464	14,305
Other, net		530	(6)
Total Noninterest Income		15,994	14,299
Insurance Segment [Member] | Not Topic 606 [Member
Revenue From Contract With Customer [Line Items]
Total Noninterest Income	[1]	$ 0	$ 0
[1] Noninterest income not in scope for FASB ASC Topic 606 includes customer derivatives revenue and miscellaneous credit card fee income within bank card and other fees; mortgage banking, net; amortization of tax credits, accretion of the FDIC indemnification asset, cash surrender value on various life insurance policies, earnings on Trustmark’s non-qualified deferred compensation plans, other partnership investments and rental income within other, net; and security gains (losses), net.

Defined Benefit and Other Pos_3

Defined Benefit and Other Postretirement Benefits - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Trustmark Capital Accumulation Plan [Member] | Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions [Member]
Net periodic benefit cost [Abstract]
Service cost	$ 10	$ 13
Interest cost	62	73
Expected return on plan assets	(24)	(26)
Recognized net loss due to lump sum settlements	0	25
Net periodic benefit cost	48	85
Supplemental Retirement Plan [Member]
Net periodic benefit cost [Abstract]
Service cost	11	17
Interest cost	477	520
Amortization of prior service cost	28	28
Recognized net actuarial loss	95	77
Net periodic benefit cost	$ 611	$ 642

Defined Benefit and Other Pos_4

Defined Benefit and Other Postretirement Benefits - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Trustmark Capital Accumulation Plan [Member] | Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Trustmark's minimum required contribution to the Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions	$ 132

Stock and Incentive Compensat_3

Stock and Incentive Compensation - Additional Information (Details)	3 Months Ended
	Mar. 31, 2024
Performance Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total shareholder return, performance measure	100%
Time Based Award [Member] | Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Time Based Award [Member] | Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	1 year

Stock and Incentive Compensat_4

Stock and Incentive Compensation - Summary of Stock Plan Activity (Details) - Stock and Incentive Compensation Plan [Member]	3 Months Ended
	Mar. 31, 2024 shares
Performance Units [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	174,214
Granted (in shares)	89,928
Released from restriction (in shares)	(54,973)
Forfeited (in shares)	0
Nonvested shares, end of period (in shares)	209,169
Time-Vested Awards [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	358,252
Granted (in shares)	139,226
Released from restriction (in shares)	(103,594)
Forfeited (in shares)	(2,334)
Nonvested shares, end of period (in shares)	391,550

Stock and Incentive Compensat_5

Stock and Incentive Compensation - Compensation Expense for Awards and Units Under Stock Plan (Details) - Stock and Incentive Compensation Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Compensation expense [Abstract]
Recognized compensation expense	$ 2,238	$ 1,715
Performance Units [Member]
Compensation expense [Abstract]
Recognized compensation expense	462	278
Time-Vested Units [Member]
Compensation expense [Abstract]
Recognized compensation expense	$ 1,776	$ 1,437

Contingencies - Additional Info

Contingencies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Loss Contingencies [Line Items]
Unused commitments to extend credit	$ 4,792	$ 5,424
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Potential exposure to credit loss in the event of nonperformance	$ 139.5	137.3
Letters of credit, maturity term - maximum	3 years
Collateral held, fair value	$ 33.1	$ 31.3

Contingencies - Summary of Chan

Contingencies - Summary of Changes in ACL on Off-Balance Sheet Credit Exposures (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Balance at beginning of period	$ 34,057	$ 36,838
PCL, off-balance sheet credit exposures	(192)	(2,242)
Balance at end of period	$ 33,865	$ 34,596

Earnings Per Share (EPS) - Weig

Earnings Per Share (EPS) - Weighted-Average Shares Used to Calculate Basic and Diluted EPS (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Basic shares	61,128,000	61,011,000
Dilutive shares	220,000	182,000
Diluted shares	61,348,000	61,193,000

Earnings Per Share (EPS) - Addi

Earnings Per Share (EPS) - Additional Information (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Weighted-average antidilutive stock awards (in shares)	0	0

Statements of Cash Flows - Cash

Statements of Cash Flows - Cash Flows Supplementary Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of cash flows specific transaction amounts [Abstract]
Interest expense paid on deposits and borrowings	$ 98,327	$ 54,823
Noncash transfers from loans to other real estate	$ 2,228	$ 300

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Details) - USD ($)	Mar. 31, 2024	Dec. 05, 2023	Dec. 06, 2022
Stockholders Equity [Line items]
Capital conservation buffer rate	2.50%
Stock Repurchase Program 3 [Member]
Stockholders Equity [Line items]
Amount of stock authorized for repurchase		$ 50,000	$ 50,000

Shareholders' Equity - Table of

Shareholders' Equity - Table of Actual Regulatory Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Trustmark Corporation [Member] | Common Equity Tier 1 Capital (to Risk Weighted Assets) [Member]
Common Equity Tier One Risk Based Capital [Abstract]
Actual Regulatory Capital Amount	$ 1,543,460	$ 1,521,665
Actual Regulatory Capital Ratio	10.12%	10.04%
Minimum Regulatory Capital Required Ratio	7%	7%
Minimum Regulatory Provision to be Well-Capitalized Ratio
Trustmark Corporation [Member] | Tier 1 Capital (to Risk Weighted Assets) [Member]
Tier 1 Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,603,460	$ 1,581,665
Actual Regulatory Capital Ratio	10.51%	10.44%
Minimum Regulatory Capital Required Ratio	8.50%	8.50%
Minimum Regulatory Provision to be Well-Capitalized Ratio
Trustmark Corporation [Member] | Total Capital (to Risk Weighted Assets) [Member]
Total Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,895,697	$ 1,862,246
Actual Regulatory Capital Ratio	12.42%	12.29%
Minimum Regulatory Capital Required Ratio	10.50%	10.50%
Minimum Regulatory Provision to be Well-Capitalized Ratio
Trustmark Corporation [Member] | Tier 1 Leverage (to Average Assets) [Member]
Tier 1 Leverage (to Average Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,603,460	$ 1,581,665
Actual Regulatory Capital Ratio	8.76%	8.62%
Minimum Regulatory Capital Required Ratio	4%	4%
Minimum Regulatory Provision to be Well-Capitalized Ratio
Trustmark National Bank [Member] | Common Equity Tier 1 Capital (to Risk Weighted Assets) [Member]
Common Equity Tier One Risk Based Capital [Abstract]
Actual Regulatory Capital Amount	$ 1,620,495	$ 1,602,327
Actual Regulatory Capital Ratio	10.62%	10.58%
Minimum Regulatory Capital Required Ratio	7%	7%
Minimum Regulatory Provision to be Well-Capitalized Ratio	6.50%	6.50%
Trustmark National Bank [Member] | Tier 1 Capital (to Risk Weighted Assets) [Member]
Tier 1 Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,620,495	$ 1,602,327
Actual Regulatory Capital Ratio	10.62%	10.58%
Minimum Regulatory Capital Required Ratio	8.50%	8.50%
Minimum Regulatory Provision to be Well-Capitalized Ratio	8%	8%
Trustmark National Bank [Member] | Total Capital (to Risk Weighted Assets) [Member]
Total Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,789,195	$ 1,759,426
Actual Regulatory Capital Ratio	11.73%	11.61%
Minimum Regulatory Capital Required Ratio	10.50%	10.50%
Minimum Regulatory Provision to be Well-Capitalized Ratio	10%	10%
Trustmark National Bank [Member] | Tier 1 Leverage (to Average Assets) [Member]
Tier 1 Leverage (to Average Assets) [Abstract]
Actual Regulatory Capital Amount	$ 1,620,495	$ 1,602,327
Actual Regulatory Capital Ratio	8.87%	8.75%
Minimum Regulatory Capital Required Ratio	4%	4%
Minimum Regulatory Provision to be Well-Capitalized Ratio	5%	5%

Shareholders' Equity - Net Chan

Shareholders' Equity - Net Change in Components of Accumulated Other Comprehensive Income (Loss) and the Related Tax Effects (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax amount	$ (9,908)	$ 43,723
Other Comprehensive Income (Loss), Tax, Total	2,477	(10,701)
Other comprehensive income (loss), before reclassifications, net of tax amount	(11,138)	30,726
Reclassification from accumulated other comprehensive income, current period, net of tax amount	(3,707)	(2,296)
Other comprehensive income (loss), net of tax amount	(7,431)	33,022
Securities Available for Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before reclassifications, before tax amount	(2,552)	30,534
Other comprehensive income (loss), change in net unrealized holding loss on securities transferred to held to maturity, before tax amount	3,661	3,859
Other comprehensive income (loss), before tax amount	1,109	34,393
Other comprehensive income (loss), before reclassifications, tax (expense) benefit	638	(7,404)
Other comprehensive income (loss), change in net unrealized holding loss on securities transferred to held to maturity, tax (expense) benefit	(915)	(965)
Other Comprehensive Income (Loss), Tax, Total	(277)	(8,369)
Other comprehensive income (loss), before reclassifications, net of tax amount	(1,914)	23,130
Other comprehensive income (loss), change in net unrealized holding loss on securities transferred to held to maturity, net of tax amount	2,746	2,894
Other comprehensive income (loss), net of tax amount	832	26,024
Net Change in Prior Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from accumulated other comprehensive income, current period, before tax amount	28	28
Reclassification from accumulated other comprehensive income, current period, tax (expense) benefit	(7)	(7)
Reclassification from accumulated other comprehensive income, current period, net of tax amount	21	21
Recognized Net Loss Due to Lump Sum Settlements [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from accumulated other comprehensive income, current period, before tax amount	0	25
Reclassification from accumulated other comprehensive income, current period, tax (expense) benefit	0	(6)
Reclassification from accumulated other comprehensive income, current period, net of tax amount	0	19
Change in Net Actuarial Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from accumulated other comprehensive income, current period, before tax amount	95	77
Reclassification from accumulated other comprehensive income, current period, tax (expense) benefit	(24)	(19)
Reclassification from accumulated other comprehensive income, current period, net of tax amount	71	58
Pension and Other Postretirement Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from accumulated other comprehensive income, current period, before tax amount	123	130
Reclassification from accumulated other comprehensive income, current period, tax (expense) benefit	(31)	(32)
Reclassification from accumulated other comprehensive income, current period, net of tax amount	92	98
Cash Flow Hedge Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before reclassifications, before tax amount	(15,960)	6,269
Reclassification from accumulated other comprehensive income, current period, before tax amount	4,820	2,931
Other comprehensive income (loss), before tax amount	(11,140)	9,200
Other comprehensive income (loss), before reclassifications, tax (expense) benefit	3,990	(1,567)
Reclassification from accumulated other comprehensive income, current period, tax (expense) benefit	(1,205)	(733)
Other Comprehensive Income (Loss), Tax, Total	2,785	(2,300)
Other comprehensive income (loss), before reclassifications, net of tax amount	(11,970)	4,702
Reclassification from accumulated other comprehensive income, current period, net of tax amount	3,615	2,198
Other comprehensive income (loss), net of tax amount	$ (8,355)	$ 6,900

Shareholders' Equity - Changes

Shareholders' Equity - Changes in Balances of Component of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 1,661,847	$ 1,492,268
Other comprehensive income (loss) before reclassification	(11,138)	30,726
Amounts reclassified from accumulated other comprehensive income (loss)	3,707	2,296
Other comprehensive income (loss), net of tax amount	(7,431)	33,022
Balance	1,682,599	1,562,099
Securities Available for Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(204,670)	(254,442)
Other comprehensive income (loss) before reclassification	832	26,024
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income (loss), net of tax amount	832	26,024
Balance	(203,838)	(228,418)
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(6,075)	(5,792)
Other comprehensive income (loss) before reclassification	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	92	98
Other comprehensive income (loss), net of tax amount	92	98
Balance	(5,983)	(5,694)
Cash Flow Hedge Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(8,978)	(15,169)
Other comprehensive income (loss) before reclassification	(11,970)	4,702
Amounts reclassified from accumulated other comprehensive income (loss)	3,615	2,198
Other comprehensive income (loss), net of tax amount	(8,355)	6,900
Balance	(17,333)	(8,269)
Accumulated Other Comprehensive (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(219,723)	(275,403)
Balance	$ (227,154)	$ (242,381)

Fair Value - Financial Assets a

Fair Value - Financial Assets and Liabilities Measured at Fair Value Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 1,702,299	$ 1,762,878
Loans held for sale (LHFS)	172,937	184,812
Mortgage servicing rights (MSR)	138,044	131,870	$ 127,206	$ 129,677
U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	372,424	372,368
U.S. Government Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	5,594	5,792
Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,702,299	1,762,878
Loans held for sale (LHFS)	172,937	184,812
Mortgage servicing rights (MSR)	138,044	131,870
Other assets - derivatives	16,953	23,316
Other liabilities - derivatives	$ 40,803	$ 35,600
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets	Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Recurring Basis [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 372,424	$ 372,368
Recurring Basis [Member] | U.S. Government Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	5,594	5,792
Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,324,281	1,384,718
Level 1 [Member] | Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	372,424	372,368
Loans held for sale (LHFS)	0	0
Mortgage servicing rights (MSR)	0	0
Other assets - derivatives	1,152	7,685
Other liabilities - derivatives	102	21
Level 1 [Member] | Recurring Basis [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	372,424	372,368
Level 1 [Member] | Recurring Basis [Member] | U.S. Government Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Level 1 [Member] | Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Level 2 [Member] | Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,329,875	1,390,510
Loans held for sale (LHFS)	172,937	184,812
Mortgage servicing rights (MSR)	0	0
Other assets - derivatives	14,644	14,786
Other liabilities - derivatives	40,701	35,579
Level 2 [Member] | Recurring Basis [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Level 2 [Member] | Recurring Basis [Member] | U.S. Government Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	5,594	5,792
Level 2 [Member] | Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,324,281	1,384,718
Level 3 [Member] | Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Loans held for sale (LHFS)	0	0
Mortgage servicing rights (MSR)	138,044	131,870
Other assets - derivatives	1,157	845
Other liabilities - derivatives	0	0
Level 3 [Member] | Recurring Basis [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Level 3 [Member] | Recurring Basis [Member] | U.S. Government Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Level 3 [Member] | Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 0	$ 0

Fair Value - Changes in Level 3

Fair Value - Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Mortgage Banking Income	Mortgage Banking Income
MSR [Member] | Recurring Basis [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		$ 131,870	$ 129,677
Total net (loss) gain included in Mortgage banking, net	[1]	3,197	(5,117)
Additions		2,977	2,646
Sales		0	0
Ending Balance		138,044	127,206
The amount of total gains (losses) for the period included in earnings that are attributable to the change in unrealized gains or losses still held, end of period		5,123	(3,972)
Other Assets - Derivatives [Member] | Recurring Basis [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		845	157
Total net (loss) gain included in Mortgage banking, net		1,047	1,288
Additions		0	0
Sales		(735)	(105)
Ending Balance		1,157	1,340
The amount of total gains (losses) for the period included in earnings that are attributable to the change in unrealized gains or losses still held, end of period		$ 927	$ 531
[1] Total net (loss) gain included in Mortgage banking, net relating to the MSR includes changes in fair value due to market changes and due to run-off.

Fair Value - Additional Informa

Fair Value - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Outstanding balances in collateral dependent related to allowance for credit losses	$ 42,900		$ 49,100
Collateral dependent related to allowance for credit losses	12,600		12,400
Foreclosed assets remeasured after initial recognition	194	$ 430
Write-downs of allowance for foreclosed assets after initial recognition	34	20
Noninterest gain (loss) Mortgage banking, net for changes in fair value of LHFS	(1,500)	944
Interest and fees on fair value option LHFS	1,700	$ 1,500
Serviced GNMA loans eligible for repurchase	$ 77,700		$ 78,800

Fair Value - Carrying Amounts a

Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	$ 1,415,025	$ 1,426,279
Deposits	15,338,557	15,569,763
Federal funds purchased and securities sold under repurchase agreements	393,215	405,745
Other borrowings	482,027	483,230
Subordinated notes	123,537	123,482
Junior subordinated debt securities	61,856	61,856
Level 2 [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and short-term investments	606,261	975,543
Securities held to maturity	1,415,025	1,426,279
Deposits	15,338,557	15,569,763
Federal funds purchased and securities sold under repurchase agreements	393,215	405,745
Other borrowings	482,027	483,230
Subordinated notes	123,537	123,482
Junior subordinated debt securities	61,856	61,856
Level 2 [Member] | Estimate Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and short-term investments	606,261	975,543
Securities held to maturity	1,333,014	1,355,504
Deposits	15,320,852	15,553,417
Federal funds purchased and securities sold under repurchase agreements	393,215	405,745
Other borrowings	482,024	483,226
Subordinated notes	110,625	108,125
Junior subordinated debt securities	47,011	48,856
Level 3 [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	12,914,945	12,811,157
Level 3 [Member] | Estimate Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	$ 12,809,237	$ 12,762,505

Fair Value - Fair Value and the

Fair Value - Fair Value and the Contractual Principal Outstanding of the LHFS (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair value and the contractual principal outstanding of the LHFS [Abstract]
Fair value of LHFS	$ 95,197	$ 105,974
LHFS contractual principal outstanding	93,598	102,994
Fair value less unpaid principal	$ 1,599	$ 2,980

Derivative Financial Instrume_3

Derivative Financial Instruments - Additional Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) Contract	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) Contract
Designated as Hedging Instrument [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total excluded components of earnings recognition	$ 85,000	$ 9,000
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	1,225,000,000		$ 1,125,000,000
Interest and fees on LHFS and LHFI reclassified as a reduction over twelve months	15,500,000
Designated as Hedging Instrument [Member] | Interest Rate Floor [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	$ 1,225,000,000		$ 1,125,000,000
Derivatives not Designated as Hedging Instruments [Member] | Beneficiary [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements | Contract	7		6
Aggregate notional amount of credit risk participation agreements	$ 44,900,000		$ 40,100,000
Derivatives not Designated as Hedging Instruments [Member] | Guarantor [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of risk participation agreements | Contract	35		35
Aggregate notional amount of credit risk participation agreements	$ 304,100,000		$ 304,700,000
Derivatives not Designated as Hedging Instruments [Member] | Mortgage Servicing Rights Hedge [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	301,000,000		285,000,000
Net (negative) positive ineffectiveness on MSR fair value	(1,100,000)	$ (1,800,000)
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	1,470,000,000		1,500,000,000
Termination value of derivatives	0		1,400,000
Collateral Posted	40,000		2,000,000
Derivatives not Designated as Hedging Instruments [Member] | Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	128,500,000		109,500,000
Valuation adjustment	(208,000,000)		(994,000)
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Lock Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	88,500,000		61,900,000
Valuation adjustment	$ 1,200,000		$ 845,000

Derivative Financial Instrume_4

Derivative Financial Instruments - Fair Value of Derivative Instruments (Details) - USD ($) $ in Thousands		Mar. 31, 2024	Dec. 31, 2023
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		$ 14,640	$ 14,781
Fair value of derivative liability		40,461	34,522
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	[1]	49	1,182
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	[1]	2,442	267
Designated as Hedging Instrument [Member] | Interest Rate Floor [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		1,591	1,689
Derivatives not Designated as Hedging Instruments [Member] | Credit Risk Participation Agreement [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		4	5
Derivatives not Designated as Hedging Instruments [Member] | Credit Risk Participation Agreement [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability		32	63
Derivatives not Designated as Hedging Instruments [Member] | Future Contracts [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		1,135	7,505
Derivatives not Designated as Hedging Instruments [Member] | Forward Contracts [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability		208	994
Derivatives not Designated as Hedging Instruments [Member] | Exchange Traded Purchased Options [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		17	180
Derivatives not Designated as Hedging Instruments [Member] | OTC Written Options (Rate Locks) [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset		1,157	845
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	[1]	13,000	11,910
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	[1]	38,019	34,255
Derivatives not Designated as Hedging Instruments [Member] | Exchange Traded Written Options [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability		$ 102	$ 21
[1] In accordance with GAAP, the variation margin collateral payments made or received for interest rate swaps that are centrally cleared are legally characterized as settled. As a result, the centrally cleared interest rate swaps included in other assets and other liabilities are presented on a net basis in the accompanying consolidated balance sheets.

Derivative Financial Instrume_5

Derivative Financial Instruments - Effects of Derivative Instruments on Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivatives, Fair Value [Line Items]
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest and Fee Income, Loan and Lease, Held-in-Portfolio	Interest and Fee Income, Loan and Lease, Held-in-Portfolio
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) reclassified from accumulated other comprehensive income (loss) and recognized in interest and fees on LHFS & LHFI	$ (4,820)	$ (2,931)
Derivatives not Designated as Hedging Instruments [Member] | Mortgage Banking, Net [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in mortgage banking, net	(5,126)	2,455
Derivatives not Designated as Hedging Instruments [Member] | Bank Card and Other Fees [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in bank card and other fees	$ (56)	$ (10)

Derivative Financial Instrume_6

Derivative Financial Instruments - Schedule of Amount Included in Other Comprehensive Income (Loss) for Derivative Instruments Designated as Hedges of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in other comprehensive income (loss), net of tax	$ (3,615)	$ (2,198)
Derivatives in Hedging Relationships [Member]
Derivatives, Fair Value [Line Items]
Amount of gain (loss) recognized in other comprehensive income (loss), net of tax	$ (11,970)	$ 4,702

Derivative Financial Instrume_7

Derivative Financial Instruments - Information about Financial Instruments that are Eligible for Offset in the Consolidated Balance Sheets (Details) - Interest Rate Swap [Member] - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Offsetting Derivative Assets
Gross Amounts of Recognized Assets, Offsetting of Derivative Assets	$ 14,640	$ 14,781
Gross Amounts Offset in the Statement of Financial Position, Offsetting of Derivative Assets	0	0
Net Amounts of Assets presented in the Statement of Financial Position, Offsetting of Derivative Assets	14,640	14,781
Financial Instruments, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Assets	(3,746)	(4,339)
Cash Collateral Received, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Assets	(2,500)	0
Net Amount, Offsetting of Derivative Assets	8,394	10,442
Offsetting Derivative Liabilities
Gross Amounts of Recognized Liabilities, Offsetting of Derivative Liabilities	40,461	34,522
Gross Amounts Offset in the Statement of Financial Position, Offsetting of Derivative Liabilities	0	0
Net Amounts of Liabilities presented in the Statement of Financial Position, Offsetting of Derivative Liabilities	40,461	34,522
Financial Instruments, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Liabilities	(3,746)	(4,339)
Cash Collateral Posted, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Liabilities	(40)	(2,040)
Net Amount, Offsetting of Derivative Liabilities	$ 36,675	$ 28,143

Segment Information - Additiona

Segment Information - Additional Information (Details)	3 Months Ended
	Mar. 31, 2024 Segment
Segment Reporting [Abstract]
Number of segments in which the business operates	3

Segment Information - Schedule

Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Net interest income	$ 132,830	$ 137,595
Provision for credit losses	7,516	1,002
Noninterest income	55,349	51,377
Noninterest expense	131,146	128,327
Income Before Income Taxes	49,517	59,643
Income taxes	7,982	9,343
Net Income	41,535	50,300
Selected Financial Information
Total assets	18,376,612	18,877,178	$ 18,722,189
Depreciation and amortization	8,563	7,666
General Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	131,517	136,159
Provision for credit losses	7,348	934
Noninterest income	30,398	28,359
Noninterest expense	111,708	109,590
Income Before Income Taxes	42,859	53,994
Income taxes	6,309	7,924
Net Income	36,550	46,070
Selected Financial Information
Total assets	18,093,454	18,578,910
Depreciation and amortization	8,367	7,443
Wealth Management [Member]
Segment Reporting Information [Line Items]
Net interest income	1,316	1,439
Provision for credit losses	168	68
Noninterest income	8,957	8,719
Noninterest expense	7,991	8,034
Income Before Income Taxes	2,114	2,056
Income taxes	523	513
Net Income	1,591	1,543
Selected Financial Information
Total assets	178,165	207,414
Depreciation and amortization	62	69
Insurance [Member]
Segment Reporting Information [Line Items]
Net interest income	(3)	(3)
Noninterest income	15,994	14,299
Noninterest expense	11,447	10,703
Income Before Income Taxes	4,544	3,593
Income taxes	1,150	906
Net Income	3,394	2,687
Selected Financial Information
Total assets	104,993	90,854
Depreciation and amortization	$ 134	$ 154

Accounting Policies Recently _3

Accounting Policies Recently Adopted and Pending Accounting Pronouncements - Additional Information (Details)	Mar. 31, 2024
Accounting Standards Update 2023-07 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2024
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
Accounting Standards Update 2023-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2025
Change in accounting principle, accounting standards update, immaterial effect [true false]	true