Trustmark (TRMK) 10-Q 8 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 30, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	TRUSTMARK CORP
Entity Central Index Key	36,146
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		67,729,434
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Trading Symbol	TRMK

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Assets
Cash and due from banks (noninterest-bearing)		$ 379,590	$ 327,706
Federal funds sold and securities purchased under reverse repurchase agreements		500	500
Securities available for sale (at fair value)		2,365,554	2,356,682
Securities held to maturity (fair value: $1,154,415-2017; $1,157,046-2016)		1,156,067	1,158,643
Loans held for sale (LHFS)		174,090	175,927
Loans held for investment (LHFI)	[1]	8,004,657	7,851,213
Less allowance for loan losses, LHFI		72,445	71,265
Net LHFI		7,932,212	7,779,948
Acquired loans		218,242	272,247
Less allowance for loan losses, acquired loans		10,006	11,397
Net acquired loans		208,236	260,850
Net LHFI and acquired loans		8,140,448	8,040,798
Premises and equipment, net		183,311	184,987
Mortgage servicing rights		82,758	80,239
Goodwill		366,156	366,156
Identifiable intangible assets		19,117	20,680
Other real estate		55,968	62,051
Other assets		566,802	577,964
Total Assets		13,490,361	13,352,333
Deposits:
Noninterest-bearing		3,209,727	2,973,238
Interest-bearing		6,894,745	7,082,774
Total deposits		10,104,472	10,056,012
Federal funds purchased and securities sold under repurchase agreements		524,335	539,817
Short-term borrowings		864,690	769,778
Long-term FHLB advances		250,994	251,049
Junior subordinated debt securities		61,856	61,856
Other liabilities		146,053	153,613
Total Liabilities		11,952,400	11,832,125
Shareholders' Equity
Common stock, no par value: Authorized: 250,000,000 shares Issued and outstanding: 67,729,434 shares - 2017; 67,628,618 shares - 2016		14,112	14,091
Capital surplus		365,951	366,563
Retained earnings		1,200,903	1,185,352
Accumulated other comprehensive loss, net of tax		(43,005)	(45,798)
Total Shareholders' Equity		1,537,961	1,520,208
Total Liabilities and Shareholders' Equity		$ 13,490,361	$ 13,352,333
[1]	During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized.

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets
Securities held to maturity, fair value	$ 1,154,415	$ 1,157,046
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)	67,729,434	67,628,618
Common stock, outstanding (in shares)	67,729,434	67,628,618

Consolidated Statements of Inco

Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Interest Income
Interest and fees on LHFS & LHFI	$ 79,407	$ 72,286
Interest and fees on acquired loans	5,189	7,022
Interest on securities:
Taxable	19,197	20,086
Tax exempt	845	973
Interest on federal funds sold and securities purchased under reverse repurchase agreements	1	1
Other interest income	267	230
Total Interest Income	104,906	100,598
Interest Expense
Interest on deposits	3,945	3,038
Interest on federal funds purchased and securities sold under repurchase agreements	698	431
Other interest expense	2,673	2,389
Total Interest Expense	7,316	5,858
Net Interest Income	97,590	94,740
Provision for loan losses, LHFI	2,762	2,243
Provision for loan losses, acquired loans	(1,605)	1,309
Net Interest Income After Provision for Loan Losses	96,433	91,188
Noninterest Income
Service charges on deposit accounts	10,832	11,081
Bank card and other fees	6,500	6,918
Mortgage banking, net	10,185	8,699
Insurance commissions	9,212	8,593
Wealth management	7,413	7,407
Other, net	1,891	888
Security losses, net	0	(310)
Total Noninterest Income	46,033	43,276
Noninterest Expense
Salaries and employee benefits	57,302	57,201
Services and fees	15,332	14,475
Net occupancy - premises	6,238	6,188
Equipment expense	5,998	6,094
Other real estate expense	1,759	181
FDIC assessment expense	2,640	2,811
Other expense	12,788	11,994
Total Noninterest Expense	102,057	98,944
Income Before Income Taxes	40,409	35,520
Income taxes	9,161	8,517
Net Income	$ 31,248	$ 27,003
Earnings Per Share
Basic	$ 0.46	$ 0.40
Diluted	0.46	0.40
Dividends Per Share	$ 0.23	$ 0.23

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income per consolidated statements of income	$ 31,248	$ 27,003
Unrealized gains on available for sale securities and transferred securities:
Unrealized holding gains arising during the period	1,411	21,825
Less: adjustment for net losses realized in net income	0	191
Change in net unrealized holding loss on securities transferred to held to maturity	761	1,682
Pension and other postretirement benefit plans:
Net change in prior service costs	39	38
Recognized net loss due to lump sum settlement	0	261
Change in net actuarial loss	486	545
Derivatives:
Change in the accumulated gain (loss) on effective cash flow hedge derivatives	35	(820)
Less: adjustment for loss realized in net income	61	99
Other comprehensive income, net of tax	2,793	23,821
Comprehensive income	$ 34,041	$ 50,824

Consolidated Condensed Statemen

Consolidated Condensed Statements of Changes in Shareholders' Equity (Unaudited) $ in Thousands	USD ($)
Balance at Dec. 31, 2015	$ 1,473,057
Statement Of Stockholders Equity [Abstract]
Net income per consolidated statements of income	27,003
Other comprehensive income, net of tax	23,821
Common stock dividends paid	(15,640)
Common stock issued-net, long-term incentive plan	(799)
Excess tax expense from stock-based compensation arrangements	(147)
Compensation expense, long-term incentive plan	961
Balance at Mar. 31, 2016	1,508,256
Balance at Dec. 31, 2016	1,520,208
Statement Of Stockholders Equity [Abstract]
Net income per consolidated statements of income	31,248
Other comprehensive income, net of tax	2,793
Common stock dividends paid	(15,697)
Common stock issued-net, long-term incentive plan	(1,543)
Compensation expense, long-term incentive plan	952
Balance at Mar. 31, 2017	$ 1,537,961

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating Activities
Net income per consolidated statements of income	$ 31,248	$ 27,003
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses, net	1,157	3,552
Depreciation and amortization	9,031	8,721
Net amortization of securities	2,612	2,087
Securities losses, net	0	310
Gains on sales of loans, net	(3,550)	(2,591)
Deferred income tax provision	3,900	125
Proceeds from sales of loans held for sale	263,614	238,007
Purchases and originations of loans held for sale	(263,232)	(267,422)
Originations of mortgage servicing rights	(3,440)	(3,072)
Earnings on bank-owned life insurance	(1,227)	(1,226)
Net decrease (increase) in other assets	6,375	(3,511)
Net decrease in other liabilities	(6,693)	(7,185)
Other operating activities, net	90	7,730
Net cash provided by operating activities	39,885	2,528
Investing Activities
Proceeds from maturities, prepayments and calls of securities held to maturity	43,854	72,168
Proceeds from maturities, prepayments and calls of securities available for sale	119,742	99,722
Proceeds from sales of securities available for sale	0	24,693
Purchases of securities held to maturity	(40,556)	(50,031)
Purchases of securities available for sale	(128,430)	(113,654)
Net proceeds from bank-owned life insurance	0	604
Net decrease in federal funds sold and securities purchased under reverse repurchase agreements	0	250
Net (increase) decrease in member bank stock	(144)	8,280
Net increase in loans	(102,573)	(153,989)
Purchases of premises and equipment	(6,319)	(2,814)
Proceeds from sales of premises and equipment	5,050	0
Proceeds from sales of other real estate	6,856	10,328
Purchases of software	(1,065)	(1,565)
Investments in tax credit and other partnerships	(17)	(46)
Net cash used in investing activities	(103,602)	(106,054)
Financing Activities
Net increase in deposits	48,460	45,413
Net (decrease) increase in federal funds purchased and securities sold under repurchase agreements	(15,482)	25,394
Net increase (decrease) in short-term borrowings	99,879	(65)
Payments on long-term FHLB advances	(16)	(30)
Common stock dividends	(15,697)	(15,640)
Shares withheld to pay taxes	(1,543)	(799)
Net cash provided by financing activities	115,601	54,273
Increase (decrease) in cash and cash equivalents	51,884	(49,253)
Cash and cash equivalents at beginning of period	327,706	277,751
Cash and cash equivalents at end of period	$ 379,590	$ 228,498

Business, Basis of Financial St

Business, Basis of Financial Statement Presentation and Principles of Consolidation	3 Months Ended
	Mar. 31, 2017
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 193 offices at March 31, 2017 in Alabama, 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 2016 Annual Report on Form 10-K. 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 2017 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.

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2017
Business Combinations [Abstract]
Business Combinations	Note 2 – Business Combinations On April 7, 2017, Trustmark Corporation completed its merger with RB Bancorporation. RB Bancorporation, with assets of $201.2 million as of March 31, 2017, was the holding company for Reliance Bank, which had seven offices serving the Huntsville, Alabama metropolitan service area (MSA). Reliance Bank was merged into Trustmark National Bank simultaneously with the merger of Trustmark and RB Bancorporation. Under the terms of the Merger Agreement dated November 14, 2016, Trustmark paid $22.00 in cash for each share of RB Bancorporation common stock outstanding, which represented total consideration for RB Bancorporation common shareholders of approximately $23.7 million. Trustmark will incur approximately $3.0 million of one-time expenses related to the merger with RB Bancorporation. T he estimated fair values of RB Bancorporation’s assets and liabilities are currently being determined and will be subject to refinement as additional information relative to the closing date fair values become available through the measurement period, which is not to exceed one year from the acquisition date of April 7, 2017. The merger with RB Bancorporation was consistent with Trustmark’s strategic plan to selectively expand the Trustmark franchise and enhance the Trustmark franchise in north Alabama.

Securities Available for Sale a

Securities Available for Sale and Held to Maturity	3 Months Ended
	Mar. 31, 2017
Investments Debt And Equity Securities [Abstract]
Securities Available for Sale and Held to Maturity	Note 3 – 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, 2017 and December 31, 2016 ($ in thousands): Securities Available for Sale Securities Held to Maturity March 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value U.S. Government agency obligations Issued by U.S. Government agencies $ 53,700 $ 376 $ (829 ) $ 53,247 $ — $ — $ — $ — Issued by U.S. Government sponsored agencies 256 18 — 274 3,658 223 — 3,881 Obligations of states and political subdivisions 107,930 2,001 (36 ) 109,895 46,273 1,619 (12 ) 47,880 Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,281 286 (900 ) 42,667 14,977 261 (66 ) 15,172 Issued by FNMA and FHLMC 738,408 1,877 (7,071 ) 733,214 118,733 264 (936 ) 118,061 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,205,842 5,353 (8,476 ) 1,202,719 771,296 2,961 (6,271 ) 767,986 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 223,338 1,197 (997 ) 223,538 201,130 1,420 (1,115 ) 201,435 Total $ 2,372,755 $ 11,108 $ (18,309 ) $ 2,365,554 $ 1,156,067 $ 6,748 $ (8,400 ) $ 1,154,415 December 31, 2016 U.S. Government agency obligations Issued by U.S. Government agencies $ 56,272 $ 416 $ (925 ) $ 55,763 $ — $ — $ — $ — Issued by U.S. Government sponsored agencies 257 19 — 276 3,647 355 — 4,002 Obligations of states and political subdivisions 113,541 1,945 (113 ) 115,373 46,303 1,476 (27 ) 47,752 Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,222 340 (776 ) 42,786 15,478 280 (52 ) 15,706 Issued by FNMA and FHLMC 638,809 1,773 (9,498 ) 631,084 81,299 223 (1,084 ) 80,438 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,271,198 5,865 (9,112 ) 1,267,951 803,474 3,208 (6,519 ) 800,163 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 242,869 1,766 (1,186 ) 243,449 208,442 1,758 (1,215 ) 208,985 Total $ 2,366,168 $ 12,124 $ (21,610 ) $ 2,356,682 $ 1,158,643 $ 7,300 $ (8,897 ) $ 1,157,046 During 2013, Trustmark reclassified approximately $1.099 billion of securities available for sale to securities held to maturity. The securities were transferred at fair value, which became the cost basis for the securities held to maturity. At the date of transfer, the net unrealized holding loss on the available for sale securities totaled approximately $46.6 million ($28.8 million, net of tax). The net unrealized holding loss is 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 the transfer. At March 31, 2017, the net unamortized, unrealized loss on the transferred securities included in accumulated other comprehensive loss in the accompanying balance sheet totaled approximately $23.0 million ($14.2 million, net of tax). Temporarily Impaired Securities The tables below include securities with gross unrealized losses segregated by length of impairment at March 31, 2017 and December 31, 2016 ($ in thousands): Less than 12 Months 12 Months or More Total March 31, 2017 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses U.S. Government agency obligations Issued by U.S. Government agencies $ 6,941 $ (102 ) $ 34,020 $ (727 ) $ 40,961 $ (829 ) Obligations of states and political subdivisions 9,551 (44 ) 652 (4 ) 10,203 (48 ) Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 42,618 (964 ) 212 (2 ) 42,830 (966 ) Issued by FNMA and FHLMC 598,901 (8,006 ) 46 (1 ) 598,947 (8,007 ) Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,067,305 (11,926 ) 72,596 (2,821 ) 1,139,901 (14,747 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 185,475 (2,111 ) 1,081 (1 ) 186,556 (2,112 ) Total $ 1,910,791 $ (23,153 ) $ 108,607 $ (3,556 ) $ 2,019,398 $ (26,709 ) December 31, 2016 U.S. Government agency obligations Issued by U.S. Government agencies $ 9,420 $ (142 ) $ 33,248 $ (783 ) $ 42,668 $ (925 ) Obligations of states and political subdivisions 20,539 (135 ) 654 (5 ) 21,193 (140 ) Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,615 (822 ) 222 (6 ) 43,837 (828 ) Issued by FNMA and FHLMC 588,352 (10,582 ) — — 588,352 (10,582 ) Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,127,501 (12,722 ) 76,196 (2,909 ) 1,203,697 (15,631 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 244,050 (2,311 ) 4,655 (90 ) 248,705 (2,401 ) Total $ 2,033,477 $ (26,714 ) $ 114,975 $ (3,793 ) $ 2,148,452 $ (30,507 ) 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. Because 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 maturity, Trustmark does not consider these investments to be other-than-temporarily impaired at March 31, 2017. There were no other-than-temporary impairments for the three months ended March 31, 2017 and 2016. Security Gains and Losses Gains and losses as a result of calls and dispositions of securities, as well as any associated proceeds, were as follows for the periods presented ($ in thousands): Three Months Ended March 31, Available for Sale 2017 2016 Proceeds from calls and sales of securities $ — $ 24,693 Gross realized gains — 32 Gross realized (losses) — (342 ) Realized gains and losses are determined using the specific identification method and are included in noninterest income as security losses, net. Securities Pledged Securities with a carrying value of $1.990 billion and $1.999 billion at March 31, 2017 and December 31, 2016, respectively, were pledged to collateralize public deposits and securities sold under repurchase agreements and for other purposes as permitted by law. At both March 31, 2017 and December 31, 2016, none of these securities were pledged under the Federal Reserve Discount Window program to provide additional contingency funding capacity. Contractual Maturities The amortized cost and estimated fair value of securities available for sale and held to maturity at March 31, 2017, by contractual maturity, are shown below ($ 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 Available for Sale Securities Held to Maturity Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 31,880 $ 32,032 $ 145 $ 145 Due after one year through five years 85,618 87,786 36,380 37,765 Due after five years through ten years 6,881 6,880 13,406 13,851 Due after ten years 37,507 36,718 — — 161,886 163,416 49,931 51,761 Mortgage-backed securities 2,210,869 2,202,138 1,106,136 1,102,654 Total $ 2,372,755 $ 2,365,554 $ 1,156,067 $ 1,154,415

Loans Held for Investment (LHFI

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI	3 Months Ended
	Mar. 31, 2017
Accounts Notes Loans And Financing Receivable Gross Allowance And Net [Abstract]
Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI	Note 4 – Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI At March 31, 2017 and December 31, 2016, LHFI consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 859,927 $ 831,437 Secured by 1-4 family residential properties 1,656,837 1,660,043 Secured by nonfarm, nonresidential properties 2,064,352 2,034,176 Other real estate secured 399,636 318,148 Commercial and industrial loans 1,540,783 1,528,434 Consumer loans 166,314 170,562 State and other political subdivision loans 910,493 917,515 Other loans 406,315 390,898 LHFI (1) 8,004,657 7,851,213 Less allowance for loan losses, LHFI 72,445 71,265 Net LHFI $ 7,932,212 $ 7,779,948 (1) During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized. 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, 2017, 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 At March 31, 2017 and December 31, 2016, the carrying amounts of nonaccrual LHFI were $61.3 million and $49.2 million, respectively. Included in these amounts were $12.4 million and $14.4 million, respectively, of nonaccrual LHFI classified as troubled debt restructurings (TDRs). No material interest income was recognized in the income statement on nonaccrual LHFI for each of the periods ended March 31, 2017 and 2016. The following table details nonaccrual LHFI by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 2,856 $ 3,323 Secured by 1-4 family residential properties 20,537 20,329 Secured by nonfarm, nonresidential properties 11,492 8,482 Other real estate secured 191 402 Commercial and industrial loans 25,410 15,824 Consumer loans 325 300 State and other political subdivision loans — — Other loans 496 574 Total nonaccrual LHFI $ 61,307 $ 49,234 The following tables provide an aging analysis of past due and nonaccrual LHFI by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Past Due 30-59 Days 60-89 Days 90 Days or (1) Total Nonaccrual Current Loans Total LHFI Loans secured by real estate: Construction, land development and other land $ 504 $ 35 $ 217 $ 756 $ 2,856 $ 856,315 $ 859,927 Secured by 1-4 family residential properties 5,738 1,814 612 8,164 20,537 1,628,136 1,656,837 Secured by nonfarm, nonresidential properties 626 214 — 840 11,492 2,052,020 2,064,352 Other real estate secured 61 — 228 289 191 399,156 399,636 Commercial and industrial loans 813 51 12 876 25,410 1,514,497 1,540,783 Consumer loans 1,495 194 238 1,927 325 164,062 166,314 State and other political subdivision loans — — — — — 910,493 910,493 Other loans 1 40 — 41 496 405,778 406,315 Total $ 9,238 $ 2,348 $ 1,307 $ 12,893 $ 61,307 $ 7,930,457 $ 8,004,657 (1) Past due 90 days or more but still accruing interest. December 31, 2016 Past Due 30-59 Days 60-89 Days 90 Days or (1) Total Nonaccrual Current Loans Total LHFI Loans secured by real estate: Construction, land development and other land $ 248 $ 37 $ 54 $ 339 $ 3,323 $ 827,775 $ 831,437 Secured by 1-4 family residential properties 5,308 2,434 1,436 9,178 20,329 1,630,536 1,660,043 Secured by nonfarm, nonresidential properties 606 100 — 706 8,482 2,024,988 2,034,176 Other real estate secured 179 — — 179 402 317,567 318,148 Commercial and industrial loans 571 213 — 784 15,824 1,511,826 1,528,434 Consumer loans 1,561 330 341 2,232 300 168,030 170,562 State and other political subdivision loans 1,035 — — 1,035 — 916,480 917,515 Other loans 178 53 — 231 574 390,093 390,898 Total $ 9,686 $ 3,167 $ 1,831 $ 14,684 $ 49,234 $ 7,787,295 $ 7,851,213 (1) Past due 90 days or more but still accruing interest. Impaired LHFI As of January 1, 2017, Trustmark modified its presentation of individually evaluated impaired LHFI in the accompanying notes to the consolidated financial statements to include all commercial nonaccrual LHFI of $500 thousand or more, which are specifically reviewed for impairment and deemed impaired, and all LHFI classified as TDRs in accordance with FASB ASC Topic 310-10-50-20. Previously, Trustmark presented all nonaccrual LHFI and LHFI classified as TDRs as impaired loans. Nonaccrual LHFI includes both individually evaluated impaired LHFI as well as smaller balance homogeneous loans that are collectively evaluated for impairment. As a result of this change in presentation, these smaller balance homogeneous nonaccrual LHFI are included within the LHFI collectively evaluated for impairment category. All prior period information has been reclassified to conform to the current period presentation. Trustmark’s individually evaluated impaired LHFI are primarily collateral dependent loans. 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. Once this estimated net realizable value has been determined, the value used in the impairment assessment is updated. At the time a LHFI that has been individually evaluated for impairment is deemed to be impaired, the full difference between book value and the most likely estimate of the collateral’s net realizable value is charged off. As subsequent events dictate and estimated net realizable values decline, required reserves may be established or further adjustments recorded. No material interest income was recognized in the income statement on impaired LHFI for each of the periods ended March 31, 2017 and 2016. At March 31, 2017 and December 31, 2016, individually evaluated impaired LHFI consisted of the following ($ in thousands): March 31, 2017 LHFI Unpaid Principal Balance With No Related Allowance Recorded With an Allowance Recorded Total Carrying Amount Related Allowance Average Recorded Investment Loans secured by real estate: Construction, land development and other land $ 4,977 $ 1,661 $ 336 $ 1,997 $ 111 $ 2,219 Secured by 1-4 family residential properties 6,351 203 4,589 4,792 1,357 4,720 Secured by nonfarm, nonresidential properties 11,512 6,438 2,753 9,191 852 7,705 Other real estate secured — — — — — — Commercial and industrial loans 23,343 13,130 9,877 23,007 1,562 18,338 Consumer loans 1 — 1 1 — 2 State and other political subdivision loans — — — — — — Other loans 95 95 — 95 — 95 Total $ 46,279 $ 21,527 $ 17,556 $ 39,083 $ 3,882 $ 33,079 December 31, 2016 LHFI Unpaid Principal Balance With No Related Allowance Recorded With an Allowance Recorded Total Carrying Amount Related Allowance Average Recorded Investment Loans secured by real estate: Construction, land development and other land $ 5,691 $ 2,260 $ 181 $ 2,441 $ 103 $ 2,943 Secured by 1-4 family residential properties 6,134 221 4,428 4,649 960 4,639 Secured by nonfarm, nonresidential properties 8,562 5,784 435 6,219 221 6,703 Other real estate secured — — — — — 500 Commercial and industrial loans 14,593 11,461 2,208 13,669 1,976 14,258 Consumer loans 2 — 2 2 — 2 State and other political subdivision loans — — — — — — Other loans 95 95 — 95 — 95 Total $ 35,077 $ 19,821 $ 7,254 $ 27,075 $ 3,260 $ 29,140 Troubled Debt Restructurings A TDR occurs when a borrower is experiencing financial difficulties, and for related economic or legal reasons, a concession is granted to the borrower that Trustmark would not otherwise consider. Whatever the form of concession that might be granted by Trustmark, Management’s objective is to enhance collectability by obtaining more cash or other value from the borrower or by increasing the probability of receipt by granting the concession than by not granting it. Other concessions may arise from court proceedings or may be imposed by law. In addition, TDRs also include those credits that are extended or renewed to a borrower who is not able to obtain funds from sources other than Trustmark at a market interest rate for new debt with similar risk. All loans whose terms have been modified in a troubled debt restructuring are evaluated for impairment under FASB ASC Topic 310. Accordingly, Trustmark measures any loss on the restructuring in accordance with that guidance. A TDR in which Trustmark receives physical possession of the borrower’s assets, regardless of whether formal foreclosure or repossession proceedings take place, is accounted for in accordance with FASB ASC Subtopic 310-40, “Troubled Debt Restructurings by Creditors.” Thus, the loan is treated as if assets have been received in satisfaction of the loan and reported as a foreclosed asset. At March 31, 2017 and December 31, 2016, Trustmark held $234 thousand and $269 thousand, respectively, of foreclosed residential real estate as a result of foreclosure or in substance repossession of consumer mortgage LHFI classified as TDRs. Consumer mortgage LHFI classified as TDRs in the process of formal foreclosure proceedings totaled $107 thousand at March 31, 2017compared to $101 thousand at December 31, 2016. A TDR may be returned to accrual status if Trustmark is reasonably assured of repayment of principal and interest under the modified terms and the borrower has demonstrated sustained performance under those terms for a period of at least six months. Otherwise, the restructured loan must remain on nonaccrual. At March 31, 2017 and 2016, LHFI classified as TDRs totaled $12.4 million and $9.2 million, respectively, and were comprised of credits with interest-only payments for an extended period of time which totaled $9.5 million and $5.7 million, respectively. The remaining TDRs at March 31, 2017 and 2016 resulted from real estate loans discharged through Chapter 7 bankruptcy that were not reaffirmed or from payment or maturity extensions. For TDRs, Trustmark had a related loan loss allowance of $382 thousand and $1.7 million at March 31, 2017 and 2016, respectively. LHFI classified as TDRs are charged down to the most likely fair value estimate less an estimated cost to sell for collateral dependent loans, which would approximate net realizable value. There were no specific charge-offs related to TDRs for the three months ended March 31, 2017 or 2016. The following tables illustrate the impact of modifications classified as TDRs as well as those TDRs modified within the last 12 months for which there was a payment default during the period for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Troubled Debt Restructurings Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Construction, land development and other land loans 1 $ 341 $ 325 — $ — $ — Loans secured by 1-4 family residential properties 7 334 338 2 71 71 Total 8 $ 675 $ 663 2 $ 71 $ 71 Three Months Ended March 31, 2017 2016 TDRs that Subsequently Defaulted Number of Contracts Recorded Investment Number of Contracts Recorded Investment Loans secured by 1-4 family residential properties 1 $ — 1 $ 17 Commercial and industrial 2 — — — Total 3 $ — 1 $ 17 Trustmark’s TDRs have resulted primarily from allowing the borrower to pay interest-only for an extended period of time rather than from forgiveness. Accordingly, as shown above, these TDRs have a similar recorded investment for both the pre-modification and post-modification disclosure. Trustmark has utilized loans 90 days or more past due to define payment default in determining TDRs that have subsequently defaulted. The following tables detail LHFI classified as TDRs by loan type at March 31, 2017 and 2016 ($ in thousands): March 31, 2017 Accruing Nonaccrual Total Loans secured by real estate: Construction, land development and other land $ — $ 642 $ 642 Secured by 1-4 family residential properties — 3,070 3,070 Secured by nonfarm, nonresidential properties — 841 841 Commercial and industrial loans — 7,845 7,845 Consumer loans — 1 1 Total TDRs $ — $ 12,399 $ 12,399 March 31, 2016 Accruing Nonaccrual Total Loans secured by real estate: Construction, land development and other land $ — $ 845 $ 845 Secured by 1-4 family residential properties 1,444 2,086 3,530 Secured by nonfarm, nonresidential properties 799 3,566 4,365 Commercial and industrial loans — 448 448 Total TDRs $ 2,243 $ 6,945 $ 9,188 Credit Quality Indicators Trustmark’s loan 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 homogenous 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 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, completeness and organization 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 insure 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 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 loan portfolio. • 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 loan portfolio. Collateral exceptions occur when certain collateral documentation is either not present, is not considered current or has expired. • 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) and Regulation O requirements. 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 adverse 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 all 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. Each commercial loan is assigned a credit risk grade that is an indication for the likelihood of default and is not a direct indication of loss at default. The loss at default aspect of the subject risk ratings is neither uniform across the nine primary commercial loan groups or constant between the geographic areas. To account for the variance in the loss at default aspects of the risk rating system, the loss expectations for each risk rating are integrated into the allowance for loan loss methodology where the calculated loss at default is allotted for each individual risk rating with respect to the individual loan group and unique geographic area. The loss at default aspect of the reserve methodology is calculated each quarter as a component of the overall reserve factor for each risk grade by loan group and geographic area. To enhance this process, loans of a certain size that are rated in one of the criticized categories are routinely reviewed to establish an expectation of loss, if any, and if such examination indicates that the level of reserve is not adequate to cover the expectation of loss, a special reserve or impairment is generally applied. The distribution of the losses is accomplished by means of a loss distribution model that assigns a loss factor to each risk rating (1 to 9) in each commercial loan pool. A factor is not applied to risk rate 10 as loans classified as Losses are charged off within the period that the loss is determined and are not carried on Trustmark’s books over quarter-end. The expected loss distribution is spread across the various risk ratings by the perceived level of risk for loss. The nine grade scale described above ranges from a negligible risk of loss to an identified loss across its breadth. The loss distribution factors are graduated through the scale on a basis proportional to the degree of risk that appears manifest in each individual rating and assumes that migration through the loan grading system will occur. 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 concentrations both on the underlying credit quality of each individual loan portfolio as well as the adherence to Trustmark’s loan policy and the loan administration process. In general, Asset Review conducts reviews of each lending area within a six to eighteen month window depending on the overall credit quality results of the individual area. 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 thirty 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 TDRs. Quarterly, the Credit Quality Review Committee reviews and modifies continuous action plans for all credits risk rated seven or worse for relationships of $100 thousand or more. In addition, a semi-annual review of significant development, commercial construction, multi-family and non-owner occupied projects is performed. The review assesses each particular project with respect to location, project valuations, progress of completion, leasing status, current financial information, rents, operating expenses, cash flow, adherence to budget and projections and other information as applicable. Summary results are reviewed by Senior and Regional Credit Officers in addition to the Chief Credit Officer with a determination as to the appropriateness of existing risk ratings and accrual status. Consumer Credits Consumer LHFI that do not meet a minimum custom credit score are reviewed quarterly by Management. The Retail Credit Review Committee reviews the volume and percentage of approvals that did not meet the minimum passing custom score by region, individual location, and officer to ensure that Trustmark continues to originate quality loans. Trustmark monitors the levels and severity of past due consumer LHFI on a daily basis through its collection activities. A detailed assessment of consumer LHFI delinquencies is performed monthly at both a product and market level by delivery channel, which incorporates the perceived level of risk at time of underwriting. Trustmark also monitors its consumer LHFI delinquency trends by comparing them to quarterly industry averages. The tables below present LHFI by loan type and credit quality indicator at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Commercial LHFI Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 790,145 $ — $ 6,567 $ 463 $ 797,175 Secured by 1-4 family residential properties 129,742 219 6,610 210 136,781 Secured by nonfarm, nonresidential properties 2,012,125 9,172 41,597 760 2,063,654 Other real estate secured 388,398 9,938 680 — 399,016 Commercial and industrial loans 1,390,084 18,807 130,806 1,086 1,540,783 Consumer loans — — — — — State and other political subdivision loans 893,139 6,450 10,904 — 910,493 Other loans 399,144 — 2,609 347 402,100 Total $ 6,002,777 $ 44,586 $ 199,773 $ 2,866 $ 6,250,002 Consumer LHFI Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual Subtotal Total LHFI Loans secured by real estate: Construction, land development and other land $ 62,185 $ 446 $ — $ 121 $ 62,752 $ 859,927 Secured by 1-4 family residential properties 1,495,639 6,638 612 17,167 1,520,056 1,656,837 Secured by nonfarm, nonresidential properties 698 — — — 698 2,064,352 Other real estate secured 620 — — — 620 399,636 Commercial and industrial loans — — — — — 1,540,783 Consumer loans 164,063 1,689 238 324 166,314 166,314 State and other political subdivision loans — — — — — 910,493 Other loans 4,175 40 — — 4,215 406,315 Total $ 1,727,380 $ 8,813 $ 850 $ 17,612 $ 1,754,655 $ 8,004,657 December 31, 2016 Commercial LHFI Pass - Categories 1-6 Special Mention - Category 7 Substandard Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 752,318 $ 9,567 $ 8,086 $ 465 $ 770,436 Secured by 1-4 family residential properties 124,615 170 6,162 129 131,076 Secured by nonfarm, nonresidential properties 1,989,554 4,394 38,913 584 2,033,445 Other real estate secured 315,829 762 890 — 317,481 Commercial and industrial loans 1,386,155 7,095 134,199 985 1,528,434 Consumer loans — — — — — State and other political subdivision loans 899,935 6,450 11,130 — 917,515 Other loans 382,890 — 2,685 350 385,925 Total $ 5,851,296 $ 28,438 $ 202,065 $ 2,513 $ 6,084,312 Consumer LHFI Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual Subtotal Total LHFI Loans secured by real estate: Construction, land development and other land $ 60,701 $ 188 $ 54 $ 58 $ 61,001 $ 831,437 Secured by 1-4 family residential properties 1,503,096 7,377 1,436 17,058 1,528,967 1,660,043 Secured by nonfarm, nonresidential properties 731 — — — 731 2,034,176 Other real estate secured 667 — — — 667 318,148 Commercial and industrial loans — — — — — 1,528,434 Consumer loans 168,031 1,891 341 299 170,562 170,562 State and other political subdivision loans — — — — — 917,515 Other loans 4,940 33 — — 4,973 390,898 Total $ 1,738,166 $ 9,489 $ 1,831 $ 17,415 $ 1,766,901 $ 7,851,213 Past Due Loans Held for Sale (LHFS) LHFS past due 90 days or more totaled $31.1 million and $28.3 million at March 31, 2017 and December 31, 2016, respectively. LHFS past due 90 days or more are serviced loans eligible for repurchase, which are fully guaranteed by the Government National Mortgage Association (GNMA). GNMA optional repurchase programs allow financial institutions to buy back individual delinquent mortgage loans that meet certain criteria from the securitized loan pool for which the institution provides servicing. At the servicer’s option and without GNMA’s prior authorization, the servicer may repurchase such a delinquent loan for an amount equal to 100 percent of the remaining principal balance of the loan. This buy-back option is considered a conditional option until the delinquency criteria are met, at which time the option becomes unconditional. When Trustmark is deemed to have regained effective control over these loans under the unconditional buy-back option, the loans can no longer be reported as sold and must be brought back onto the balance sheet as loans held for sale, regardless of whether Trustmark intends to exercise the buy-back option. These loans are reported as held for sale with the offsetting liability being reported as short-term borrowings. Trustmark did not exercise its buy-back option on any delinquent loans serviced for GNMA during the first three months of 2017 or 2016. Allowance for Loan Losses, LHFI Trustmark’s allowance for loan loss methodology for commercial LHFI is based upon regulatory guidance from its primary regulator and GAAP. The methodology segregates the commercial purpose and commercial construction LHFI portfolios into nine separate loan types (or pools) which have similar characteristics such as repayment, collateral and risk profiles. The nine basic loan pools are further segregated into Trustmark’s five key market regions, Alabama, Florida, Mississippi, Tennessee and Texas, to take into consideration the uniqueness of each market. A 10-point risk rating system is utilized for each separate loan pool to apply a reserve factor consisting of quantitative and qualitative components to determine the needed allowance by each loan type. As a result, there are 450 risk rate factors for commercial loan types. The nine separate pools are shown below: Commercial Purpose LHFI • Real Estate – Owner-Occupied • Real Estate – Non-Owner Occupied • Working Capital • Non-Working Capital • Land • Lots and Development • Political Subdivisions Commercial Construction LHFI • 1 to 4 Family • Non-1 to 4 Family The quantitative factors of the allowance methodology reflect a twelve-quarter rolling average of net charge-offs by loan type within each key market region. This allows for a greater sensitivity to current trends, such as economic changes, as well as current loss profiles and creates a more accurate depiction of historical losses. Qualitative factors used in the allowance methodology include the following: • National and regional economic trends and conditions • Impact of recent performance trends • Experience, ability and effectiveness of management • Adherence to Trustmark’s loan policies, procedures and internal controls • Collateral, financial and underwriting exception trends • Credit concentrations • Loan facility risk • Acquisitions • Catastrophe Each qualitative factor is converted to a scale ranging from 0 (No risk) to 100 (High Risk), other than the last two factors, which are applied on a dollar-for-dollar basis to ensure that the combination of such factors is proportional. The resulting ratings from the individual factors are weighted and summed to establish the weighted-average qualitative factor within each key market region. The allowance for loan loss methodology segregates the consumer LHFI portfolio into homogeneous pools of loans that contain similar structure, repayment, collateral and risk profiles. These homogeneous pools of loans are shown below: • Residential Mortgage • Direct Consumer • Junior Lien on 1-4 Family Residential Properties • Credit Cards • Overdrafts The historical loss experience for these pools is determined by calculating a 12-quarter rolling average of net charge-offs, which is applied to each pool to establish the quantitative aspect of the methodology. Where, in Management’s estimation, the calculated loss experience does not fully cover the anticipated loss for a pool, an estimate is also applied to each pool to establish the qualitative aspect of the methodology, which represents the perceived risks across the loan portfolio at the current point in time. This qualitative methodology utilizes five separate factors made up of unique components that when weighted and combined produce an estimated level of reserve for each of the loan pools. The five qualitative factors include the following: • Economic indicators • Performance trends • Management experience • Credit concentrations • Loan policy exceptions The risk measure for each factor is converted to a scale ranging from 0 (No risk) to 100 (High Risk) to ensure that the combination of such factors is proportional. The determination of the risk measurement for each qualitative factor is done for all markets combined. The resulting estimated reserve factor is then applied to each pool. The resulting ratings from the individual factors are weighted and summed to establish the weighted-average qualitative factor of a specific loan portfolio. This weighted-average qualitative factor is then applied over the five loan pools. Trustmark’s loan policy dictates the guidelines to be followed in determining when a loan is charged off. Commercial purpose loans are charged off when a determination is made that the loan is uncollectible and continuance as a bankable asset is not warranted or an impairment evaluation indicates that a value adjustment is necessary. Consumer loans secured by 1-4 family residential real estate are generally charged off or written down when the credit becomes severely delinquent and the balance exceeds the fair value of the property less costs to sell. Non-real estate consumer purpose loans, both secured and unsecured, are generally charged off in full during the month in which the loan becomes 120 days past due. Credit card loans are generally charged off in full when the loan becomes 180 days pa

Acquired Loans

Acquired Loans	3 Months Ended
	Mar. 31, 2017
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities [Abstract]
Acquired Loans	Note 5 – Acquired Loans The presentation of the acquired loans disclosures has been modified from prior filings to eliminate the segmentation of acquired noncovered loans and acquired covered loans due to the significantly reduced size of the acquired covered loan portfolio. Trustmark’s loss share agreement with the FDIC covering the acquired covered loans other than loans secured by 1-4 family residential properties expired on June 30, 2016. Trustmark’s loss share agreement with the FDIC covering the acquired covered loans secured by 1-4 family residential properties will expire in 2021. Effective July 1, 2016, all acquired covered loans excluding the acquired covered loans secured by 1-4 family residential properties were reclassified to acquired noncovered loans. The revised presentation reflects total acquired loan information in the accompanying consolidated balance sheets and tables below. All prior period information has been reclassified to conform to the current period presentation. At March 31, 2017 and December 31, 2016, acquired loans consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 17,651 $ 20,850 Secured by 1-4 family residential properties 54,721 69,540 Secured by nonfarm, nonresidential properties 92,075 103,820 Other real estate secured 16,275 19,010 Commercial and industrial loans 20,691 36,896 Consumer loans 2,664 3,365 Other loans 14,165 18,766 Acquired loans 218,242 272,247 Less allowance for loan losses, acquired loans 10,006 11,397 Net acquired loans $ 208,236 $ 260,850 The following table presents changes in the net carrying value of the acquired loans for the periods presented ($ in thousands): Acquired Impaired Acquired Not ASC 310-30 (1) Carrying value, net at January 1, 2016 $ 310,762 $ 67,657 Accretion to interest income 18,405 40 Payments received, net (111,522 ) (24,953 ) Other (2) (134 ) — Less change in allowance for loan losses, acquired loans 596 (1 ) Carrying value, net at December 31, 2016 218,107 42,743 Transfers (3) — (36,719 ) Accretion to interest income 3,673 — Payments received, net (14,645 ) (6,024 ) Other (2) (290 ) — Less change in allowance for loan losses, acquired loans 1,391 — Carrying value, net at March 31, 2017 $ 208,236 $ — (1) "Acquired Not ASC 310-30" loans consist of revolving credit agreements and commercial leases that are not in scope for FASB ASC Topic 310-30, "Loans and Debt Securities Acquired with Deteriorated Credit Quality." (2) Includes miscellaneous timing adjustments as well as acquired loan terminations through foreclosure, charge-off and other terminations. (3) During the first quarter of 2017, Trustmark transferred the remaining balance of the “Acquired Not ASC 310-30” loans to LHFI due to the discount on these loans being fully amortized. Under FASB ASC Topic 310-30, the accretable yield is the excess of expected cash flows at acquisition over the initial fair value of acquired impaired loans and is recorded as interest income over the estimated life of the loans using the effective yield method if the timing and amount of the future cash flows is reasonably estimable. The following table presents changes in the accretable yield for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Accretable yield at beginning of period $ (38,918 ) $ (52,672 ) Accretion to interest income 3,673 5,230 (Additions)/disposals (183 ) 1,067 Reclassification from nonaccretable difference (1) (1,788 ) (3,403 ) Accretable yield at end of period $ (37,216 ) $ (49,778 ) (1) Reclassifications from nonaccretable difference are due to lower loss expectations and improvements in expected cash flows. The following tables present the components of the allowance for loan losses on acquired loans for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 11,397 $ 11,992 Provision for loan losses, acquired loans (1,605 ) 1,309 Loans charged-off — (397 ) Recoveries 214 631 Net recoveries 214 234 Balance at end of period $ 10,006 $ 13,535 As discussed in Note 4 - Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI, 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 segregate the level of risk across the ten unique risk ratings. These credit quality measures are unique to commercial loans. Credit quality for consumer loans is based on individual credit scores, aging status of the loan and payment activity. The tables below present the acquired loans by loan type and credit quality indicator at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Commercial Loans Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 11,322 $ 93 $ 4,130 $ 522 $ 16,067 Secured by 1-4 family residential properties 12,649 52 3,573 52 16,326 Secured by nonfarm, nonresidential properties 73,125 — 18,389 515 92,029 Other real estate secured 12,775 — 2,536 544 15,855 Commercial and industrial loans 12,354 18 7,202 1,117 20,691 Consumer loans — — — — — Other loans 8,613 — 5,432 117 14,162 Total acquired loans $ 130,838 $ 163 $ 41,262 $ 2,867 $ 175,130 Consumer Loans Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual (1) Subtotal Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 1,469 $ 102 $ 13 $ — $ 1,584 $ 17,651 Secured by 1-4 family residential properties 36,509 1,500 386 — 38,395 54,721 Secured by nonfarm, nonresidential properties 46 — — — 46 92,075 Other real estate secured 420 — — — 420 16,275 Commercial and industrial loans — — — — — 20,691 Consumer loans 2,603 58 3 — 2,664 2,664 Other loans 3 — — — 3 14,165 Total acquired loans $ 41,050 $ 1,660 $ 402 $ — $ 43,112 $ 218,242 (1) Acquired loans not accounted for under FASB ASC Topic 310-30. December 31, 2016 Commercial Loans Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 12,148 $ 99 $ 6,469 $ 322 $ 19,038 Secured by 1-4 family residential properties 14,552 61 4,066 69 18,748 Secured by nonfarm, nonresidential properties 83,271 435 19,553 511 103,770 Other real estate secured 15,344 — 2,673 565 18,582 Commercial and industrial loans 22,024 18 13,494 1,354 36,890 Consumer loans — — — — — Other loans 12,954 — 5,649 161 18,764 Total acquired loans $ 160,293 $ 613 $ 51,904 $ 2,982 $ 215,792 Consumer Loans Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual (1) Subtotal Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 1,801 $ — $ 11 $ — $ 1,812 $ 20,850 Secured by 1-4 family residential properties 48,695 1,364 709 24 50,792 69,540 Secured by nonfarm, nonresidential properties 50 — — — 50 103,820 Other real estate secured 428 — — — 428 19,010 Commercial and industrial loans 6 — — — 6 36,896 Consumer loans 3,250 51 64 — 3,365 3,365 Other loans 2 — — — 2 18,766 Total acquired loans $ 54,232 $ 1,415 $ 784 $ 24 $ 56,455 $ 272,247 (1) Acquired loans not accounted for under FASB ASC Topic 310-30. At March 31, 2017 and December 31, 2016, there were no acquired impaired loans accounted for under FASB ASC Topic 310-30 classified as nonaccrual loans. At March 31, 2017, there were no acquired loans not accounted for under FASB ASC Topic 310-30 classified as nonaccrual loans as a result of the transfer of the remaining balance of the acquired loans not accounted for under FASB ASC Topic 310-30 to the LHFI portfolio during the first quarter of 2017. Approximately $631 thousand of acquired loans not accounted for under FASB ASC Topic 310-30 were classified as nonaccrual loans at December 31, 2016. The following tables provide an aging analysis of contractually past due and nonaccrual acquired loans by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Past Due 30-59 Days 60-89 Days 90 Days or More (1) Total Nonaccrual (2) Current Loans Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 102 $ 176 $ 1,513 $ 1,791 $ — $ 15,860 $ 17,651 Secured by 1-4 family residential properties 1,568 625 683 2,876 — 51,845 54,721 Secured by nonfarm, nonresidential properties 166 1,739 1,850 3,755 — 88,320 92,075 Other real estate secured — — 576 576 — 15,699 16,275 Commercial and industrial loans 18 — 5 23 — 20,668 20,691 Consumer loans 58 — 3 61 — 2,603 2,664 Other loans — — — — — 14,165 14,165 Total acquired loans $ 1,912 $ 2,540 $ 4,630 $ 9,082 $ — $ 209,160 $ 218,242 (1) Past due 90 days or more but still accruing interest. (2) Acquired loans not accounted for under FASB ASC Topic 310-30. December 31, 2016 Past Due 30-59 Days 60-89 Days 90 Days or More (1) Total Nonaccrual (2) Current Loans Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 321 $ 100 $ 821 $ 1,242 $ — $ 19,608 $ 20,850 Secured by 1-4 family residential properties 1,495 412 1,057 2,964 41 66,535 69,540 Secured by nonfarm, nonresidential properties 1,658 38 343 2,039 328 101,453 103,820 Other real estate secured 769 — 1,445 2,214 — 16,796 19,010 Commercial and industrial loans 60 39 — 99 262 36,535 36,896 Consumer loans 51 — 64 115 — 3,250 3,365 Other loans — — — — — 18,766 18,766 Total acquired loans $ 4,354 $ 589 $ 3,730 $ 8,673 $ 631 $ 262,943 $ 272,247 (1) Past due 90 days or more but still accruing interest. (2) Acquired loans not accounted for under FASB ASC Topic 310-30.

Mortgage Banking

Mortgage Banking	3 Months Ended
	Mar. 31, 2017
Mortgage Banking [Abstract]
Mortgage Banking	Note 6 – Mortgage Banking The activity in the mortgage servicing rights (MSR) is detailed in the table below for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 80,239 $ 74,007 Origination of servicing assets 3,440 3,072 Change in fair value: Due to market changes 1,466 (6,866 ) Due to run-off (2,387 ) (2,005 ) Balance at end of period $ 82,758 $ 68,208 During the first three months of 2017 and 2016, Trustmark sold $260.1 million and $235.4 million, respectively, of residential mortgage loans. Pretax gains on these sales were recorded to noninterest income in mortgage banking, net and totaled $3.6 million for the first three months of 2017 compared to $2.6 million for the first three months of 2016. The table below details the mortgage loans sold and serviced for others at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Federal National Mortgage Association $ 4,033,540 $ 3,992,349 Government National Mortgage Association 2,307,321 2,291,398 Federal Home Loan Mortgage Corporation 53,377 55,006 Other 30,264 32,589 Total mortgage loans sold and serviced for others $ 6,424,502 $ 6,371,342 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 Lending and Selling Representations and Warranties Framework updated in May 2014, 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. Currently, putback requests primarily relate to 2009 through 2013 vintage mortgage loans. Trustmark incurred $105 thousand of mortgage loan servicing putback expenses, included in other expense, during both the first three months of 2017 and 2016. Changes in the reserve for mortgage loan servicing putback expense for mortgage loans were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 1,130 $ 1,685 Provision for putback expenses 105 105 Gains (losses) 16 (5 ) Balance at end of period $ 1,251 $ 1,785 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, 2017
Other Real Estate And Foreclosed Assets [Abstract]
Other Real Estate	Note 7 – Other Real Estate At March 31, 2017, Trustmark’s geographic other real estate distribution was concentrated primarily in its five key market regions: Alabama, Florida, Mississippi, Tennessee and Texas. The ultimate recovery of a substantial portion of the carrying amount of other real estate is susceptible to changes in market conditions in these areas. For the periods presented, changes and gains, net on other real estate were as follows ($ in thousands): Three Months Ended March 31, 2017 2016 (1) Balance at beginning of period $ 62,051 $ 78,828 Additions 1,766 3,608 Disposals (6,385 ) (8,994 ) Write-downs (1,464 ) (1,140 ) Balance at end of period $ 55,968 $ 72,302 Gain, net on the sale of other real estate included in other real estate expense $ 470 $ 1,868 (1) The changes and gains, net on other real estate for the three months ended March 31, 2016 include covered other real estate. At March 31, 2017 and December 31, 2016, other real estate by type of property consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Construction, land development and other land properties $ 35,256 $ 36,871 1-4 family residential properties 6,818 7,926 Nonfarm, nonresidential properties 13,457 16,817 Other real estate properties 437 437 Total other real estate $ 55,968 $ 62,051 At March 31, 2017 and December 31, 2016, other real estate by geographic location consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Alabama $ 13,953 $ 15,989 Florida 21,577 22,582 Mississippi (1) 14,974 15,646 Tennessee (2) 4,706 6,183 Texas 758 1,651 Total other real estate $ 55,968 $ 62,051 (1) Mississippi includes Central and Southern Mississippi Regions (2) Tennessee includes Memphis, Tennessee and Northern Mississippi Regions

Deposits

Deposits	3 Months Ended
	Mar. 31, 2017
Deposits [Abstract]
Deposits	Note 8 – Deposits At March 31, 2017 and December 31, 2016, deposits consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Noninterest-bearing demand $ 3,209,727 $ 2,973,238 Interest-bearing demand 1,927,415 1,875,312 Savings 3,295,565 3,586,369 Time 1,671,765 1,621,093 Total $ 10,104,472 $ 10,056,012

Securities Sold Under Repurchas

Securities Sold Under Repurchase Agreements	3 Months Ended
	Mar. 31, 2017
Securities Sold Under Agreements To Repurchase [Abstract]
Securities Sold Under Repurchase Agreements	Note 9 – 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 Topic 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 $277.8 million and $284.4 million at March 31, 2017 and December 31, 2016, respectively. Trustmark’s repurchase agreements are transacted under master repurchase agreements that give Trustmark, in the event of default by the counterparty, the right of offset with the same counterparty. As of March 31, 2017, all repurchase agreements were short-term and consisted primarily of sweep repurchase arrangements, under which excess deposits are “swept” into overnight repurchase agreements with Trustmark. The following table presents the securities sold under repurchase agreements by collateral pledged at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Mortgage-backed securities Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA $ 87,525 $ 75,795 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 51,691 51,212 Total securities sold under repurchase agreements $ 139,216 $ 127,007

Defined Benefit and Other Postr

Defined Benefit and Other Postretirement Benefits	3 Months Ended
	Mar. 31, 2017
Compensation And Retirement Disclosure [Abstract]
Defined Benefit and Other Postretirement Benefits	Note 10 – Defined Benefit and Other Postretirement Benefits Qualified Pension Plans Trustmark maintained a noncontributory tax-qualified defined benefit pension plan (Trustmark Capital Accumulation Plan, the “Plan”), in which substantially all associates who began employment prior to 2007 participated. The Plan provided for retirement benefits based on the length of credited service and final average compensation, as defined in the Plan, which vested upon three years of service. Benefit accruals under the Plan were frozen in 2009, with the exception of certain associates covered through plans obtained in acquisitions that were subsequently merged into the Plan. Other than the associates covered through these acquired plans that were merged into the Plan, associates have not earned additional benefits, except for interest as required by law, since the Plan was frozen. Current and former associates who participate in the Plan retain their right to receive benefits that accrued before the Plan was frozen. As previously reported, on July 26, 2016, the Board of Directors of Trustmark authorized the termination of the Plan, effective as of December 31, 2016. To satisfy commitments made by Trustmark to associates (collectively, the “Continuing Associates”) covered through acquired plans that were merged into the Plan, the Board also approved the spin-off of the portion of the Plan associated with the accrued benefits of the Continuing Associates into a new plan titled the Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions (the “Spin-Off Plan”), effective as of December 31, 2016, immediately prior to the termination of the Plan. In order to terminate the Plan, in accordance with Internal Revenue Service (IRS) and Pension Benefit Guaranty Corporation requirements, Trustmark is required to fully fund the Plan on a termination basis and will contribute the additional assets necessary to do so. The final distributions will be made from current plan assets and a one-time pension settlement expense will be recognized when paid by Trustmark during the second quarter of 2017. Participants in the Plan will have a choice of receiving a lump sum cash payment or annuity payments under a group annuity contract purchased from an insurance carrier, subject to certain exceptions. As a result of the termination of the Plan, each participant will become fully vested in his or her accrued benefits under the Plan. The Board reserved the right to defer or revoke the termination of the Plan if circumstances change such that deferral or revocation would be warranted, but has no intent to do so at this time. The following table presents information regarding the net periodic benefit cost for the Plan and the Spin-Off Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Service cost $ 63 $ 108 Interest cost 665 830 Expected return on plan assets (108 ) (1,022 ) Recognized net loss due to lump sum settlements — 423 Recognized net actuarial loss 565 661 Net periodic benefit cost $ 1,185 $ 1,000 Since the Plan was terminated, there will be no additional contributions required in the future other than amounts necessary to facilitate the plan termination. For the plan year ending December 31, 2017, Trustmark’s minimum required contribution to the Spin-Off Plan is expected to be zero; however, Management and the Board of Directors of Trustmark will monitor the Spin-Off Plan throughout 2017 to determine any additional funding requirements by the Spin-Off 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 measurement date for the plan is December 31. As a result of mergers prior to 2014, Trustmark became the administrator of small nonqualified supplemental retirement plans, for which the plan benefits were frozen prior to the respective 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, 2017 2016 Service cost $ 35 $ 74 Interest cost 561 546 Amortization of prior service cost 63 63 Recognized net actuarial loss 222 221 Net periodic benefit cost $ 881 $ 904

Stock and Incentive Compensatio

Stock and Incentive Compensation Plans	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock and Incentive Compensation Plans	Note 11 – Stock and Incentive Compensation Plans Trustmark has granted stock and incentive compensation awards subject to the provisions of the Stock and Incentive Compensation Plan (the Stock Plan). Current outstanding and future grants of stock and incentive compensation awards 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 Awards Trustmark’s performance awards vest over three years and are granted to Trustmark’s executive and senior management teams. Performance awards granted vest based on performance goals of return on average tangible equity and total shareholder return compared to a defined peer group. Performance awards are valued utilizing a Monte Carlo simulation model to estimate fair value of the awards at the grant date. These awards are recognized using the straight-line method over the requisite service period. These awards provide for achievement shares if performance measures exceed 100%. The restricted share agreement provides for voting rights and dividend privileges. Time-Vested Awards Trustmark’s time-vested awards vest over three years and are granted to members of Trustmark’s Board of Directors as well as Trustmark’s executive and senior management teams. Time-vested awards are valued utilizing the fair value of Trustmark’s stock at the grant date. These awards are recognized on the straight-line method over the requisite service period. The following table summarizes the Stock Plan activity for the periods presented: Three Months Ended March 31, 2017 Performance Awards Time-Vested Awards Nonvested shares, beginning of period 237,136 322,056 Granted 58,406 88,224 Released from restriction (62,601 ) (83,862 ) Forfeited (2,947 ) (734 ) Nonvested shares, end of period 229,994 325,684 The following table presents information regarding compensation expense for awards under the Stock Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Performance awards $ 105 $ 100 Time-vested awards 848 861 Total compensation expense $ 953 $ 961

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2017
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. These amounts are not material to Trustmark’s financial statements. 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, 2017 and 2016, Trustmark had unused commitments to extend credit of $3.052 billion and $3.007 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, 2017 and 2016, Trustmark’s maximum exposure to credit loss in the event of nonperformance by the other party for letters of credit was $109.2 million and $114.9 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, 2017 and 2016, the fair value of collateral held was $33.7 million and $30.0 million, respectively. Legal Proceedings Trustmark’s wholly-owned subsidiary, TNB, has been named as a defendant in three lawsuits related to the collapse of the Stanford Financial Group. The first is a purported class action complaint that was filed on August 23, 2009 in the District Court of Harris County, Texas, by Peggy Roif Rotstain, Guthrie Abbott, Catherine Burnell, Steven Queyrouze, Jaime Alexis Arroyo Bornstein and Juan C. Olano (collectively, Class Plaintiffs), on behalf of themselves and all others similarly situated, naming TNB and four other financial institutions unaffiliated with Trustmark as defendants. The complaint seeks to recover (i) alleged fraudulent transfers from each of the defendants in the amount of fees and other monies received by each defendant from entities controlled by R. Allen Stanford (collectively, the Stanford Financial Group) and (ii) damages allegedly attributable to alleged conspiracies by one or more of the defendants with the Stanford Financial Group to commit fraud and/or aid and abet fraud on the asserted grounds that defendants knew or should have known the Stanford Financial Group was conducting an illegal and fraudulent scheme. Plaintiffs have demanded a jury trial. Plaintiffs did not quantify damages. In November 2009, the lawsuit was removed to federal court by certain defendants and then transferred by the United States Panel on Multidistrict Litigation to federal court in the Northern District of Texas (Dallas) where multiple Stanford related matters are being consolidated for pre-trial proceedings. In May 2010, all defendants (including TNB) filed motions to dismiss the lawsuit. In August 2010, the court authorized and approved the formation of an Official Stanford Investors Committee (OSIC) to represent the interests of Stanford investors and, under certain circumstances, to file legal actions for the benefit of Stanford investors. In December 2011, the OSIC filed a motion to intervene in this action. In September 2012, the district court referred the case to a magistrate judge for hearing and determination of certain pretrial issues. In December 2012, the court granted the OSIC’s motion to intervene, and the OSIC filed an Intervenor Complaint against one of the other defendant financial institutions. In February 2013, the OSIC filed a second Intervenor Complaint that asserts claims against TNB and the remaining defendant financial institutions. The OSIC seeks to recover: (i) alleged fraudulent transfers in the amount of the fees each of the defendants allegedly received from Stanford Financial Group, the profits each of the defendants allegedly made from Stanford Financial Group deposits, and other monies each of the defendants allegedly received from Stanford Financial Group; (ii) damages attributable to alleged conspiracies by each of the defendants with the Stanford Financial Group to commit fraud and/or aid and abet fraud and conversion on the asserted grounds that the defendants knew or should have known the Stanford Financial Group was conducting an illegal and fraudulent scheme; and (iii) punitive damages. The OSIC did not quantify damages. In July 2013, all defendants (including TNB) filed motions to dismiss the OSIC’s claims. In March 2015, the court entered an order authorizing the parties to conduct discovery regarding class certification and setting a deadline for the parties to complete briefing on class certification issues. In April 2015, the court granted in part and denied in part the defendants’ motions to dismiss the Class Plaintiffs’ claims and the OSIC’s claims. The court dismissed all of the Class Plaintiffs’ fraudulent transfer claims and dismissed certain of the OSIC’s claims. The court denied the motions by TNB and the other financial institution defendants to dismiss the OSIC’s constructive fraudulent transfer claims. On June 23, 2015, the court allowed the Class Plaintiffs to file a Second Amended Class Action Complaint (SAC), which asserted new claims against TNB and certain of the other defendants for (i) aiding, abetting and participating in a fraudulent scheme, (ii) aiding, abetting and participating in violations of the Texas Securities Act, (iii) aiding, abetting and participating in breaches of fiduciary duty, (iv) aiding, abetting and participating in conversion and (v) conspiracy. On July 14, 2015, the defendants (including TNB) filed motions to dismiss the SAC and to reconsider the court’s prior denial to dismiss the OSIC’s constructive fraudulent transfer claims against TNB and the other financial institutions that are defendants in the action. On July 27, 2016, the court denied the motion by TNB and the other financial institution defendants to dismiss the SAC and also denied the motion by TNB and the other financial institution defendants to reconsider the court’s prior denial to dismiss the OSIC’s constructive fraudulent transfer claims. On August 24, 2016, TNB filed its answer to the SAC. There has been no new activity related to the SAC. The second Stanford-related lawsuit was filed on December 14, 2009 in the District Court of Ascension Parish, Louisiana, individually by Harold Jackson, Paul Blaine, Carolyn Bass Smith, Christine Nichols, and Ronald and Ramona Hebert naming TNB (misnamed as Trust National Bank) and other individuals and entities not affiliated with Trustmark as defendants. The complaint seeks to recover the money lost by these individual plaintiffs as a result of the collapse of the Stanford Financial Group (in addition to other damages) under various theories and causes of action, including negligence, breach of contract, breach of fiduciary duty, negligent misrepresentation, detrimental reliance, conspiracy, and violation of Louisiana’s uniform fiduciary, securities, and racketeering laws. The complaint does not quantify the amount of money the plaintiffs seek to recover. In January 2010, the lawsuit was removed to federal court by certain defendants and then transferred by the United States Panel on Multidistrict Litigation to federal court in the Northern District of Texas (Dallas) where multiple Stanford related matters are being consolidated for pre-trial proceedings. On March 29, 2010, the court stayed the case. TNB filed a motion to lift the stay, which was denied on February 28, 2012. In September 2012, the district court referred the case to a magistrate judge for hearing and determination of certain pretrial issues. On April 11, 2016, Trustmark learned that a third Stanford-related lawsuit had been filed on that date in the Superior Court of Justice in Ontario, Canada, by The Toronto-Dominion Bank (“TD Bank”), naming TNB and three other financial institutions not affiliated with Trustmark as defendants. The complaint seeks a declaration specifying the degree to which each of TNB and the other defendants are liable in respect of any loss and damage for which TD Bank is found to be liable in a litigation commenced against TD Bank brought by the Joint Liquidators of Stanford International Bank Limited in the Superior Court of Justice, Commercial List in Ontario, Canada (the “Joint Liquidators’ Action”), as well as contribution and indemnity in respect of any judgment, interest and costs TD Bank is ordered to pay in the Joint Liquidators’ Action. To date, TNB has not been served in connection with this action. TNB’s relationship with the Stanford Financial Group began as a result of Trustmark’s acquisition of a Houston-based bank in August 2006, and consisted of correspondent banking and other traditional banking services in the ordinary course of business. All Stanford-related lawsuits are in pre-trial stages. TNB has been named as a defendant in two separately filed but consolidated lawsuits involving two testamentary trusts created in the will of Kathleen Killebrew Paine for her two children, Carolyn Paine Davis and W.K. Paine. TNB is named as the Trustee in both trusts. The lawsuits were filed on June 30, 2014 in the Chancery Court of the First Judicial District of Hinds County, Mississippi by Jennifer Davis Michael, Elizabeth Paine Lindigrin, Wilmer Harrison Paine, Kenneth Whitworth Paine, Robert Harvey Paine and Nathan Davis, who are all children of Mrs. Davis and Mr. Paine. The complaints alleged that the plaintiffs were vested current beneficiaries of the respective trusts; that the plaintiffs should have been entitled to be considered for distributions of trust income; and that the interests of Mrs. Davis and Mr. Paine were favored over plaintiffs’ interest in both the distribution of income and in the making of trust investments. Plaintiffs sought compensatory damages, refund of trust fees and sweep fees, punitive damages, attorneys’ fees and pre- and post-judgment interest. On March 9, 2015, the court granted TNB’s motion to add Mrs. Davis and Mr. W.K. Paine as cross-defendants. Following a bench trial that concluded on January 20, 2016, the judge ordered the parties to enter into mandatory mediation. On February 22, 2016, the mediator reported to the judge that the mediation had failed to resolve the matter. On March 30, 2017, the parties agreed to the terms of a settlement of the consolidated lawsuits. On May 4, 2017, the judge approved the settlement. The judge has advised the parties that the lawsuits will be dismissed with prejudice when settlement funds have been disbursed in accordance with the terms of the settlement, which is expected to occur during the second quarter. The terms of the settlement are not material to Trustmark’s results of operations or financial condition. Trustmark and its subsidiaries are also parties to other 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. All pending legal proceedings described above are being vigorously contested. In accordance FASB ASC Topic 450-20, “Loss Contingencies,” Trustmark will establish an accrued liability for litigation matters when those matters present loss contingencies that are both probable and reasonably estimable. At the present time, Trustmark believes, based on its evaluation and the advice of legal counsel, that a loss in any such 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, 2017
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, 2017 2016 Basic shares 67,687 67,610 Dilutive shares 159 137 Diluted shares 67,846 67,747 Weighted-average antidilutive stock awards were excluded in determining diluted EPS. The following table reflects weighted-average antidilutive stock awards for the periods presented (in thousands): Three Months Ended March 31, 2017 2016 Weighted-average antidilutive stock awards 43 —

Statements of Cash Flows

Statements of Cash Flows	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 Income taxes paid $ 778 $ 376 Interest expense paid on deposits and borrowings 7,190 4,986 Noncash transfers from loans to other real estate (1) 1,766 3,608 (1) Includes transfers from covered loans to covered other real estate. Trustmark adopted the amendments of ASU 2016-09, “Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting,” effective January 1, 2017. ASU 2016-09 included amendments which affected the presentation of the accompanying consolidated statements of cash flows. Specifically, ASU 2016-09 required that excess tax benefits from employee share-based payments to be classified as an operating activity along with other income tax cash flows, and required that cash paid by an employer when directly withholding shares for tax-withholding purposes to be classified as a financing activity. Trustmark elected to present these changes on a retrospective basis in the accompanying consolidated statements of cash flows, which resulted in $147 thousand of excess tax expense from stock-based compensation arrangements being reclassified from financing activities to other operating activities, net and $799 thousand of withholding taxes paid for shares directly withheld being reclassified from other operating activities, net to financing activities for the three months ended March 31, 2016. The adoption of ASU 2016-09 did not materially affect Trustmark’s consolidated financial statements. For additional information regarding the amendments of ASU 2016-09 and the impact to Trustmark, see Note 19 – Accounting Policies Recently Adopted and Pending Accounting Pronouncements.

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2017
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 2016 Annual Report on Form 10-K, 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 the phased in capital conservation buffer of 1.250% at March 31, 2017 and 0.625% at December 31, 2016. Accumulated other comprehensive loss, net of tax, is not included in computing regulatory capital. 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, 2017, 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, 2017. To be categorized in this manner, Trustmark and TNB maintained 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, 2017, 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, 2017 and December 31, 2016 ($ in thousands): Actual Regulatory Capital Minimum To Be Well Amount Ratio Requirement Capitalized At March 31, 2017: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,223,078 12.19 % 5.750 % n/a Trustmark National Bank 1,266,309 12.63 % 5.750 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,282,919 12.79 % 7.250 % n/a Trustmark National Bank 1,266,309 12.63 % 7.250 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,365,370 13.61 % 9.250 % n/a Trustmark National Bank 1,348,760 13.45 % 9.250 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,282,919 9.86 % 4.00 % n/a Trustmark National Bank 1,266,309 9.75 % 4.00 % 5.00 % At December 31, 2016: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,209,927 12.16 % 5.125 % n/a Trustmark National Bank 1,251,329 12.58 % 5.125 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,269,660 12.76 % 6.625 % n/a Trustmark National Bank 1,251,329 12.58 % 6.625 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,352,322 13.59 % 8.625 % n/a Trustmark National Bank 1,333,991 13.41 % 8.625 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,269,660 9.90 % 4.00 % n/a Trustmark National Bank 1,251,329 9.77 % 4.00 % 5.00 % Stock Repurchase Program On March 11, 2016, the Board of Directors of Trustmark authorized a stock repurchase program under which $100.0 million of Trustmark’s outstanding common stock may be acquired through March 31, 2019. The shares may be purchased from time to time at prevailing market prices, through open market or privately negotiated transactions, depending on market conditions. Trustmark did not repurchase any shares of its common stock during the three months ended March 31, 2017 or 2016. Other Comprehensive Income and Accumulated Other Comprehensive Loss The following table presents the components of accumulated other comprehensive loss and the related tax effects allocated to each component for the three months ended March 31, 2017 and 2016 ($ in thousands). Reclassification adjustments related to securities available for sale are included in security losses, net in the accompanying consolidated statements of income. The amortization of prior service cost, recognized net loss due to lump sum settlements and change in net actuarial loss on pension and other postretirement benefit plans 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 derivative are included in other interest expense in the accompanying consolidated statements of income. Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 Before Tax Amount Tax (Expense) Benefit Net of Tax Amount Before Tax Amount Tax (Expense) Benefit Net of Tax Amount Securities available for sale and transferred securities: Unrealized holding gains arising during the period $ 2,285 $ (874 ) $ 1,411 $ 35,343 $ (13,518 ) $ 21,825 Reclassification adjustment for net losses realized in net income — — — 310 (119 ) 191 Change in net unrealized holding loss on securities transferred to held to maturity 1,232 (471 ) 761 2,724 (1,042 ) 1,682 Total securities available for sale and transferred securities 3,517 (1,345 ) 2,172 38,377 (14,679 ) 23,698 Pension and other postretirement benefit plans: Net change in prior service costs 63 (24 ) 39 62 (24 ) 38 Recognized net loss due to lump sum settlements — — — 423 (162 ) 261 Change in net actuarial loss 787 (301 ) 486 882 (337 ) 545 Total pension and other postretirement benefit plans 850 (325 ) 525 1,367 (523 ) 844 Cash flow hedge derivatives: Change in accumulated gain (loss) on effective cash flow hedge derivatives 57 (22 ) 35 (1,328 ) 508 (820 ) Reclassification adjustment for loss realized in net income 99 (38 ) 61 160 (61 ) 99 Total cash flow hedge derivatives 156 (60 ) 96 (1,168 ) 447 (721 ) Total other comprehensive income $ 4,523 $ (1,730 ) $ 2,793 $ 38,576 $ (14,755 ) $ 23,821 The following table presents the changes in the balances of each component of accumulated other comprehensive loss for the periods presented ($ in thousands). All amounts are presented net of tax. Securities Available and Transferred Securities Defined Benefit Pension Items Cash Flow Hedge Derivatives Total Balance at January 1, 2017 $ (20,800 ) $ (24,980 ) $ (18 ) $ (45,798 ) Other comprehensive income before reclassification 2,172 — 35 2,207 Amounts reclassified from accumulated other comprehensive loss — 525 61 586 Net other comprehensive income 2,172 525 96 2,793 Balance at March 31, 2017 $ (18,628 ) $ (24,455 ) $ 78 $ (43,005 ) Balance at January 1, 2016 $ (17,394 ) $ (27,840 ) $ (160 ) $ (45,394 ) Other comprehensive income (loss) before reclassification 23,507 — (820 ) 22,687 Amounts reclassified from accumulated other comprehensive loss 191 844 99 1,134 Net other comprehensive income (loss) 23,698 844 (721 ) 23,821 Balance at March 31, 2016 $ 6,304 $ (26,996 ) $ (881 ) $ (21,573 )

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2017
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 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 as of March 31, 2017 and December 31, 2016, 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, 2017 and the year ended December 31, 2016. March 31, 2017 Total Level 1 Level 2 Level 3 U.S. Government agency obligations $ 53,521 $ — $ 53,521 $ — Obligations of states and political subdivisions 109,895 — 109,895 — Mortgage-backed securities 2,202,138 — 2,202,138 — Securities available for sale 2,365,554 — 2,365,554 — Loans held for sale 174,090 — 174,090 — Mortgage servicing rights 82,758 — — 82,758 Other assets - derivatives 4,230 521 1,564 2,145 Other liabilities - derivatives 3,676 909 2,767 — December 31, 2016 Total Level 1 Level 2 Level 3 U.S. Government agency obligations $ 56,039 $ — $ 56,039 $ — Obligations of states and political subdivisions 115,373 — 115,373 — Mortgage-backed securities 2,185,270 — 2,185,270 — Securities available for sale 2,356,682 — 2,356,682 — Loans held for sale 175,927 — 175,927 — Mortgage servicing rights 80,239 — — 80,239 Other assets - derivatives 2,518 (524 ) 2,041 1,001 Other liabilities - derivatives 412 1,174 (762 ) — The changes in Level 3 assets measured at fair value on a recurring basis for the three months ended March 31, 2017 and 2016 are summarized as follows ($ in thousands): MSR Other Assets - Derivatives Balance, January 1, 2017 $ 80,239 $ 1,001 Total net (loss) gain included in Mortgage banking, net (1) (921 ) 1,955 Additions 3,440 — Sales — (811 ) Balance, March 31, 2017 $ 82,758 $ 2,145 The amount of total gains for the period included in earnings that are attributable to the change in unrealized gains or losses still held at March 31, 2017 $ 1,466 $ 342 Balance, January 1, 2016 $ 74,007 $ 1,113 Total net (loss) gain included in Mortgage banking, net (1) (8,871 ) 3,097 Additions 3,072 — Sales — (926 ) Balance, March 31, 2016 $ 68,208 $ 3,284 The amount of total (losses) gains for the period included in earnings that are attributable to the change in unrealized gains or losses still held at March 31, 2016 $ (6,866 ) $ 398 (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, 2017, which have been measured at fair value on a nonrecurring basis, include impaired LHFI. Loans for which it is probable Trustmark will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement are considered impaired. Specific allowances for impaired LHFI are based on comparisons of the recorded carrying values of the loans to the present value of the estimated cash flows of these loans at each loan’s original effective interest rate, the fair value of the collateral or the observable market prices of the loans. Impaired LHFI are primarily collateral dependent loans and are assessed using a fair value approach. Fair value estimates for collateral dependent loans are derived from appraised values based on the current market value or as-is value of the property being appraised, normally from recently received and reviewed appraisals. 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. Appraised values are adjusted down for costs associated with asset disposal. At March 31, 2017, Trustmark had outstanding balances of $39.1 million in impaired LHFI that were individually evaluated for impairment and written down to the fair value of the underlying collateral less cost to sell based on the fair value of the collateral or other unobservable input compared to $27.1 million at December 31, 2016. These individually evaluated impaired LHFI are classified as Level 3 in the fair value hierarchy. Impaired LHFI are periodically reviewed and evaluated for additional impairment and adjusted accordingly based on the same factors identified above. 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 carried at the lower of cost or estimated fair value. 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 $10.3 million were remeasured during the first three months of 2017, requiring write-downs of $1.5 million to reach their current fair values compared to $12.2 million of foreclosed assets that were remeasured during the first three months of 2016, requiring write-downs of $1.1 million. Fair Value of Financial Instruments FASB ASC Topic 825, “Financial Instruments,” requires disclosure of the fair value of financial assets and financial liabilities, including those financial assets and financial liabilities that are not measured and reported at fair value on a recurring basis or non-recurring basis. A detailed description of the valuation methodologies used in estimating the fair value of financial instruments can be found in Note 19 – Fair Value included in Item 8 of Trustmark’s Annual Report on Form 10-K for the year ended December 31, 2016. The carrying amounts and estimated fair values of financial instruments at March 31, 2017 and December 31, 2016, are as follows ($ in thousands): March 31, 2017 December 31, 2016 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial Assets: Level 2 Inputs: Cash and short-term investments $ 380,090 $ 380,090 $ 328,206 $ 328,206 Securities held to maturity 1,156,067 1,154,415 1,158,643 1,157,046 Level 3 Inputs: Net LHFI 7,932,212 8,001,968 7,779,948 7,825,009 Net acquired loans 208,236 208,236 260,850 260,850 Financial Liabilities: Level 2 Inputs: Deposits 10,104,472 10,105,262 10,056,012 10,059,794 Short-term liabilities 1,389,025 1,389,025 1,309,595 1,309,595 Long-term FHLB advances 250,994 250,994 251,049 251,050 Junior subordinated debt securities 61,856 43,299 61,856 41,057 In cases where quoted market prices are not available, fair values are generally based on estimates using present value techniques. Trustmark’s premise in present value techniques is to represent the fair values on a basis of replacement value of the existing instrument given observed market rates on the measurement date. These techniques are significantly affected by the assumptions used, including the discount rate and estimates of future cash flows. In that regard, the derived fair value estimates for those assets or liabilities cannot necessarily be substantiated by comparison to independent markets and, in many cases, may not be realizable in immediate settlement of the instruments. The estimated fair value of financial instruments with immediate and shorter-term maturities (generally 90 days or less) is assumed to be the same as the recorded book value. All nonfinancial instruments, by definition, have been excluded from these disclosure requirements. Accordingly, the aggregate fair value amounts presented do not represent the underlying value of Trustmark. The fair values of net LHFI are estimated for portfolios of loans with similar financial characteristics. For variable rate LHFI that reprice frequently with no significant change in credit risk, fair values are based on carrying values. The fair values of certain mortgage LHFI, such as 1-4 family residential properties, are based on quoted market prices of similar loans sold in conjunction with securitization transactions, adjusted for differences in loan characteristics. The fair values of other types of LHFI are estimated by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities. The processes for estimating the fair value of net LHFI described above does not represent an exit price under FASB ASC Topic 820, “Fair Value Measurements and Disclosures,” and such an exit price could potentially produce a different fair value estimate at March 31, 2017 and December 31, 2016. 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 in noninterest income in mortgage banking, net. The changes in the fair value of the LHFS are largely offset by changes in the fair value of the derivative instruments. For the three months ended March 31, 2017 and 2016, a net gain of $3.6 million and $2.8 million, respectively, was recorded in noninterest income in mortgage banking, net for changes in the fair value of the LHFS accounted for under the fair value option. Interest and fees on LHFS and LHFI for the three months ended March 31, 2017 and 2016 included $1.1 million and $867 thousand, respectively, of interest earned on the LHFS accounted for under the fair value option. 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 the 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 $38.9 million and $43.9 million at March 31, 2017 and December 31, 2016, respectively, and are included in LHFS on the accompanying consolidated balance sheets. The following table provides information about the fair value and the contractual principal outstanding of the LHFS accounted for under the fair value option as of March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Fair value of LHFS $ 135,170 $ 132,002 LHFS contractual principal outstanding 131,632 132,047 Fair value less unpaid principal $ 3,538 $ (45 )

Derivative Financial Instrument

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Note 17 – Derivative Financial Instruments Derivatives Designated as Hedging Instruments On April 4, 2013, Trustmark entered into a forward interest rate swap contract on junior subordinated debentures with a total notional amount of $60.0 million. The interest rate swap contract was designated as a derivative instrument in a cash flow hedge under FASB ASC Topic 815, “Derivatives and Hedging,” with the objective of protecting the quarterly interest payments on Trustmark’s $60.0 million of junior subordinated debentures issued to Trustmark Preferred Capital Trust I throughout the five-year period beginning December 31, 2014 and ending December 31, 2019 from the risk of variability of those payments resulting from changes in the three-month LIBOR interest rate. Under the swap, which became effective on December 31, 2014, Trustmark will pay a fixed interest rate of 1.66% and receive a variable interest rate based on three-month LIBOR on a total notional amount of $60.0 million, with quarterly net settlements. No ineffectiveness related to the interest rate swap designated as a cash flow hedge was recognized in the consolidated statements of income for the three months ended March 31, 2017 and 2016. The accumulated net after-tax gain related to the effective cash flow hedge included in accumulated other comprehensive loss totaled $78 thousand at March 31, 2017 compared to an accumulated net after-tax loss of $17 thousand December 31, 2016. Amounts reported in accumulated other comprehensive loss related to this derivative are reclassified to other interest expense as interest payments are made on Trustmark’s variable rate junior subordinated debentures. During the next twelve months, Trustmark estimates that $178 thousand will be reclassified as an increase to other interest expense. 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 were $285.5 million at March 31, 2017 compared to $262.0 million at December 31, 2016. Changes in the fair value of these exchange-traded derivative instruments are recorded in 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 positive ineffectiveness of $2.8 million and $413 thousand for the three months ended March 31, 2017 and 2016, 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 in 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 $231.0 million at March 31, 2017, with a negative valuation adjustment of $1.2 million, compared to $195.0 million, with a positive valuation adjustment of $2.8 million, at December 31, 2016. 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 in 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 $143.5 million at March 31, 2017, with a positive valuation adjustment of $2.1 million, compared to $97.9 million, with a positive valuation adjustment of $1.0 million, as of December 31, 2016. 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 in 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. As of March 31, 2017, Trustmark had interest rate swaps with an aggregate notional amount of $336.7 million related to this program, compared to $340.2 million as of December 31, 2016. 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. As of March 31, 2017 and December 31, 2016, the termination value of interest rate swaps in a liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $711 thousand and $1.2 million, respectively. As of March 31, 2017, Trustmark had posted collateral of $100 thousand 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, 2017, 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 both March 31, 2017 and December 31, 2016, Trustmark had entered into two risk participation agreements as a beneficiary with an aggregate notional amount of $14.1 million and $14.2 million, respectively. At March 31, 2017, Trustmark had entered into five risk participation agreements as a guarantor with an aggregate notional amount of $27.9 million compared to five risk participation agreements as a guarantor with an aggregate notional amount of $28.0 million at December 31, 2016. The aggregate fair values of these risk participation agreements were immaterial at March 31, 2017 and December 31, 2016. Tabular Disclosures The following tables disclose the fair value of derivative instruments in Trustmark’s consolidated balance sheets as of March 31, 2017 and December 31, 2016 as well as the effect of these derivative instruments on Trustmark’s results of operations for the periods presented ($ in thousands): March 31, 2017 December 31, 2016 Derivatives in hedging relationships Interest rate contracts: Interest rate swaps included in other assets $ 127 $ (28 ) Derivatives not designated as hedging instruments Interest rate contracts: Futures contracts included in other assets $ 299 $ (626 ) Exchange traded purchased options included in other assets 222 102 OTC written options (rate locks) included in other assets 2,145 1,001 Interest rate swaps included in other assets 1,431 2,060 Credit risk participation agreements included in other assets 6 9 Forward contracts included in other liabilities 1,175 (2,838 ) Exchange traded written options included in other liabilities 909 1,174 Interest rate swaps included in other liabilities 1,584 2,065 Credit risk participation agreements included in other liabilities 8 11 Three Months Ended March 31, 2017 2016 Derivatives in hedging relationships Amount of loss reclassified from accumulated other comprehensive loss and recognized in other interest expense $ (99 ) $ (160 ) Derivatives not designated as hedging instruments Amount of (loss) gain recognized in mortgage banking, net $ (1,544 ) $ 7,139 Amount of loss recognized in bank card and other fees (28 ) (58 ) The following table discloses the amount included in other comprehensive income, net of tax, for derivative instruments designated as cash flow hedges for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Derivatives in cash flow hedging relationship Amount of gain (loss) recognized in other comprehensive income, net of tax $ 35 $ (820 ) 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, 2017 and December 31, 2016 is presented in the following tables ($ in thousands): Offsetting of Derivative Assets As of March 31, 2017 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets presented in the Statement of Financial Position Financial Instruments Cash Collateral Received Net Amount Derivatives $ 1,558 $ — $ 1,558 $ (182 ) $ — $ 1,376 Offsetting of Derivative Liabilities As of March 31, 2017 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Liabilities presented in the Statement of Financial Position Financial Instruments Cash Collateral Posted Net Amount Derivatives $ 1,584 $ — $ 1,584 $ (182 ) $ (100 ) $ 1,302 Offsetting of Derivative Assets As of December 31, 2016 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets presented in the Statement of Financial Position Financial Instruments Cash Collateral Received Net Amount Derivatives $ 2,032 $ — $ 2,032 $ (499 ) $ — $ 1,533 Offsetting of Derivative Liabilities As of December 31, 2016 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Liabilities presented in the Statement of Financial Position Financial Instruments Cash Collateral Posted Net Amount Derivatives $ 2,065 $ — $ 2,065 $ (499 ) $ (937 ) $ 629

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2017
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 21 – Segment Information included in Part II. Item 8. – Financial Statements and Supplementary Data, of Trustmark’s 2016 Annual Report on Form 10-K. There have been no significant changes in Trustmark’s operating segments during the periods presented. 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, 2017 2016 General Banking Net interest income $ 97,411 $ 94,442 Provision for loan losses, net 1,157 3,552 Noninterest income 29,440 27,394 Noninterest expense 87,357 85,893 Income before income taxes 38,337 32,391 Income taxes 8,369 7,319 General banking net income $ 29,968 $ 25,072 Selected Financial Information Total assets $ 13,417,229 $ 12,701,364 Depreciation and amortization $ 8,836 $ 8,485 Wealth Management Net interest income $ 129 $ 245 Noninterest income 7,377 7,288 Noninterest expense 7,201 5,891 Income before income taxes 305 1,642 Income taxes 116 628 Wealth management net income $ 189 $ 1,014 Selected Financial Information Total assets $ 7,279 $ 7,329 Depreciation and amortization $ 37 $ 44 Insurance Net interest income $ 50 $ 53 Noninterest income 9,216 8,594 Noninterest expense 7,499 7,160 Income before income taxes 1,767 1,487 Income taxes 676 570 Insurance net income $ 1,091 $ 917 Selected Financial Information Total assets $ 65,853 $ 66,503 Depreciation and amortization $ 158 $ 192 Consolidated Net interest income $ 97,590 $ 94,740 Provision for loan losses, net 1,157 3,552 Noninterest income 46,033 43,276 Noninterest expense 102,057 98,944 Income before income taxes 40,409 35,520 Income taxes 9,161 8,517 Consolidated net income $ 31,248 $ 27,003 Selected Financial Information Total assets $ 13,490,361 $ 12,775,196 Depreciation and amortization $ 9,031 $ 8,721

Accounting Policies Recently Ad

Accounting Policies Recently Adopted and Pending Accounting Pronouncements	3 Months Ended
	Mar. 31, 2017
New Accounting Pronouncements And Changes In Accounting Principles [Abstract]
Accounting Policies Recently Adopted and Pending Accounting Pronouncements	Note 19 – Accounting Policies Recently Adopted and Pending Accounting Pronouncements ASU 2017-08, “ Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities.” Issued in March 2017, ASU 2017-08 amends the amortization period for certain purchased callable debt securities held at a premium. In particular, the amendments in ASU 2017-08 require the premium to be amortized to the earliest call date. The amendments do not, however, require an accounting change for securities held at a discount; instead, the discount continues to be amortized to maturity. Notably, the amendments in this ASU more closely align the amortization period of premiums and discounts to expectations incorporated in market pricing on the underlying securities. Securities within the scope of ASU 2017-08 are purchased debt securities that have explicit, noncontingent call features that are callable at fixed prices and on preset dates. The amendments of ASU 2017-08 become effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2018. As of March 31, 2017, Trustmark’s total unamortized premium for purchased debt securities within the scope of ASU 2017-08 was immaterial. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements through its effective date; however, the adoption of ASU 2017-08 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-07, “ Compensation-Retirement Benefits (Topic 715)-Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.” Issued in March 2017, ASU 2017-07 is designed to improve guidance related to the presentation of defined benefit costs in the income statement. In particular, ASU No. 2017-07 requires that an employer report the service cost component in the same line item(s) as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations, if one is presented. If a separate line item or items are used to present the other components of net benefit cost, then that line item or items must be appropriately described. However, if a separate line item or items are not used, then the line item(s) used in the income statement to present the other components of net benefit cost must be disclosed. Additionally, ASU 2017-07 allows only the service cost component to be eligible for capitalization, when applicable. The amendments of ASU 2017-07 become effective for annual periods beginning after December 15, 2017, including interim periods within those annual periods. Management is currently evaluating the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2017-07 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-04, “ Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment.” Issued in January 2017, ASU 2017-04 simplifies the manner in which an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Step 2 measures a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount of that goodwill. In computing the implied fair value of goodwill under Step 2, an entity, prior to the amendments in ASU 2017-04, had to perform procedures to determine the fair value at the impairment testing date of its assets and liabilities, including unrecognized assets and liabilities, in accordance with the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. However, under the amendments in ASU 2017-04, an entity should (1) perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount, and (2) recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value, with the understanding that the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, ASU 2017-04 removes the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment and, if it fails such qualitative test, to perform Step 2 of the goodwill impairment test. ASU 2017-04 is effective prospectively for annual, or any interim, goodwill impairment tests in fiscal years beginning after December 15, 2019. Based on Trustmark’s annual goodwill impairment test performed as of October 1, 2016, the fair value of its reporting units exceeded the carrying value and, therefore, the related goodwill was not impaired. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements through its effective date; however, the adoption of ASU 2017-04 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-01, “Business Combinations (Topic 805) - Clarifying the Definition of a Business.” Issued in January 2017, ASU 2017-01 clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses, which determines whether goodwill should be recorded or not. The amendments in ASU No. 2017-01 provide a screen to determine when a set of assets and activities (collectively, a “set”) is not a business. The screen requires that when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. This screen reduces the number of transactions that need to be further evaluated. If, however, the screen is not met, then the amendments in ASU 07-01 require that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and remove the evaluation of whether a market participant could replace missing elements. The revised definition will result in more transactions being recorded as asset acquisitions or dispositions as opposed to business acquisitions or dispositions. The amendments of ASU 2017-01 are effective for interim and annual periods beginning after December 15, 2017. Management is currently evaluating the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2017-01 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.” Issued in August 2016, ASU 2016-15 provides guidance to reduce the diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The amendments of ASU 2016-15 provide guidance on eight specific cash flow: (i) debt prepayment or debt extinguishment costs; (ii) settlement of zero-coupon bonds; (iii) contingent consideration payments made after a business combination; (iv) proceeds from the settlement of insurance claims; (v) proceeds from the settlement of corporate-owned life insurance policies, including bank-owned life insurance policies; (vi) distributions received from equity method investees; (vii) beneficial interests in securitization transactions and (viii) separately identifiable cash flows and application of the predominance principle. The amendments of ASU 2016-15 are effective for interim and annual periods beginning after December 15, 2017. Trustmark plans to adopt the amendments of ASU 2016-15 during the first quarter of 2018. Management has evaluated the amendments of ASU 2016-15 and does not believe that adoption of this ASU will impact Trustmark’s existing presentation of the applicable cash receipts and cash payments on its consolidated statements of cash flows. ASU 2016-13, “Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” Issued in June 2016, ASU 2016-13 will add FASB ASC Topic 326, “Financial Instruments-Credit Losses” and finalizes amendments to FASB ASC Subtopic 825-15, “Financial Instruments-Credit Losses.” The amendments of ASU 2016-13 are intended to provide financial statement users with more decision-useful information related to expected credit losses on financial instruments and other commitments to extend credit by replacing the current incurred loss impairment methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to determine credit loss estimates. The amendments of ASU 2016-13 eliminate the probable initial recognition threshold and, in turn, reflect an entity’s current estimate of all expected credit losses. ASU 2016-13 does not specify the method for measuring expected credit losses, and an entity is allowed to apply methods that reasonably reflect its expectations of the credit loss estimate. Additionally, the amendments of ASU 2016-13 require that credit losses on available for sale debt securities be presented as an allowance rather than as a write-down. The amendments of ASU 2016-13 are effective for interim and annual periods beginning after December 15, 2019. Earlier application is permitted for interim and annual periods beginning after December 15, 2018. Trustmark plans to adopt the amendments of ASU 2016-13 during the first quarter of 2020. Trustmark has established a steering committee which includes the appropriate members of Management to evaluate the impact this ASU will have on Trustmark’s financial position, results of operations and financial statement disclosures and determine the most appropriate method of implementing the amendments in this ASU as well as any resources needed to implement the amendments. The steering committee is currently evaluating various third-party vendors to determine the most appropriate product for Trustmark and the level of assistance that will be required for implementation. ASU 2016-09, “Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting.” Issued in March 2016, ASU 2016-09 seeks to reduce complexity in accounting standards by simplifying several aspects of the accounting for share-based payment transactions. The amendments of ASU 2016-09 include: (i) requiring all excess tax benefits and tax deficiencies to be recognized as income tax expense or benefit in the income statement; (ii) requiring excess tax benefits to be classified along with other income tax cash flows as an operating activity on the statement of cash flow; (iii) allowing an entity to make an entity-wide accounting policy election to either estimate the number of awards that expect to vest or account for forfeitures when they occur; (iv) change the threshold to qualify for equity classification to permit withholding up to the maximum statutory tax rates in the applicable jurisdictions; and (v) requiring that cash paid by an employer when directly withholding shares for tax-withholding purposes to be classified as a financing activity on the statement of cash flows. The amendments of ASU 2016-09 became effective for Trustmark on January 1, 2017 and did not have a material impact on Trustmark’s consolidated financial statements. Trustmark has made an entity-wide accounting policy election to account for forfeitures of stock awards as they occur. Changes as required by the amendments of ASU 2016-09 are presented in the accompanying consolidated statements of cash flows. ASU 2016-02, “Leases (Topic 842).” Issued in February 2016, ASU 2016-02 was issued by the FASB to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and by disclosing key information about leasing arrangements. ASU 2016-02 will, among other things, require lessees to recognize a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. ASU 2016-02 does not significantly change lease accounting requirements applicable to lessors; however, the ASU contains some targeted improvements that are intended to align, where necessary, lessor accounting with the lessee accounting model and with the updated revenue recognition guidance issued in 2014. The amendments of ASU 2016-02 are effective for interim and annual periods beginning after December 15, 2018. Trustmark plans to adopt the amendments of ASU 2016-02 beginning in the first quarter of 2019. At adoption, Trustmark will recognize a lease asset and a corresponding lease liability on its consolidated balance sheet for its total lease obligation measured on a discounted basis. As of December 31, 2016, all leases in which Trustmark was the lessee were classified as operating leases and the total outstanding lease obligation was $58.0 million, or 0.4% of total assets. Trustmark does not anticipant any material impact to its consolidated statements of income as a result of the adoption of this ASU. Trustmark has an immaterial amount of leases in which it is the lessor. Based on Management’s evaluation to date, Trustmark does not expect the amendments of ASU 2016-02 to have any material impact to these leases or the related income. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2016-02 is not expected to have a material impact on Trustmark’s consolidated financial statements. ASU 2016-01, “Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (An Amendment of the FASB Accounting Standards Codification).” Issued in January 2016, ASU 2016-01 is intended to enhance the reporting model for financial instruments to provide users of financial statements with improved decision-making information. The amendments of ASU 2016-01 include: (i) requiring equity investments, except those accounted for under the equity method of accounting or those that result in the consolidation of an investee, to be measured at fair value with changes in fair value recognized in net income; (ii) requiring a qualitative assessment to identify impairment of equity investments without readily determinable fair values; (iii) eliminating the requirement to disclose the method and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost on the balance sheet; (iv) requiring the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (v) requiring an entity that has elected the fair value option to measure the fair value of a liability to present separately in other comprehensive income the portion of the change in the fair value resulting from a change in the instrument-specific credit risk; (vi) requiring separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements and (vii) clarifying that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available for sale securities in combination with the entity’s other deferred tax assets. The amendments of ASU 2016-01 are effective for interim and annual periods beginning after December 15, 2017. Trustmark plans to adopt the amendments of ASU 2016-01 during the first quarter of 2018. Management has evaluated the impact this ASU will have on Trustmark’s consolidated financial statements. Through this evaluation, Management has determined that the principal areas impacted by the amendments of ASU 2016-01 will be Trustmark’s investment in member bank stock, which are equity securities that do not have readily determinable fair values, and various fair value related disclosures. See Note 1 – Significant Accounting Policies, “Federal Home Loan Bank (FHLB) and Federal Reserve Bank of Atlanta Stock” included in Item 8 of Trustmark’s Annual Report on Form 10-K for information regarding Trustmark’s investment in member bank stock. The adoption of ASU 2016-01 is not expected to have a material impact on Trustmark’s consolidated financial statements. ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” Issued in May 2014, ASU 2014-09 will add FASB ASC Topic 606, “Revenue from Contracts with Customers,” and will supersede revenue recognition requirements in FASB ASC Topic 605, “Revenue Recognition,” as well as certain cost guidance in FASB ASC Topic 605-35, “Revenue Recognition – Construction-Type and Production-Type Contracts.” ASU 2014-09 provides a framework for revenue recognition that replaces the existing industry and transaction specific requirements under the existing standards. ASU 2014-09 requires an entity to apply a five-step model to determine when to recognize revenue and at what amount. The model specifies that revenue should be recognized when (or as) an entity transfers control of goods or services to a customer at the amount in which the entity expects to be entitled. Depending on whether certain criteria are met, revenue should be recognized either over time, in a manner that depicts the entity’s performance, or at a point in time, when control of the goods or services are transferred to the customer. ASU 2014-09 provides that an entity should apply the following steps: (1) identify the contract(s) with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when, or as, the entity satisfies a performance obligation. In addition, the existing requirements for the recognition of a gain or loss on the transfer of non-financial assets that are not in a contract with a customer are amended to be consistent with the guidance on recognition and measurement in ASU 2014-09. The amendments of ASU 2014-09 may be applied either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying ASU 2014-09 recognized at the date of initial application. If the transition method of application is elected, the entity should also provide the additional disclosures in reporting periods that include the date of initial application of (1) the amount by which each financial statement line item is affected in the current reporting period, as compared to the guidance that was in effect before the change, and (2) an explanation of the reasons for significant changes. ASU 2015-14, “Revenue from Contracts with Customers (Topic 606)-Deferral of the Effective Date,” issued in August 2015, defers the effective date of ASU 2014-09 by one year. ASU 2015-14 provides that the amendments of ASU 2014-09 become effective for interim and annual periods beginning after December 15, 2017. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. All subsequently issued ASUs which provide additional guidance and clarifications to various aspects of FASB ASC Topic 606 will become effective when the amendments of ASU 2014-09 become effective. Trustmark plans to adopt these amendments during the first quarter of 2018. Management is continuing to evaluate the impact ASU 2014-09 will have on Trustmark’s consolidated financial statements as well as the most appropriate transition method of application. Based on this evaluation to date, Management has determined that the majority of the revenues earned by Trustmark are not within the scope of ASU 2014-09. Management also believes that for most revenue streams within the scope of ASU 2014-09, the amendments will not change the timing of when the revenue is recognized. Management will continue to evaluate the impact the adoption of ASU 2014-09 will have on Trustmark’s consolidated financial statements, focusing on noninterest income sources within the scope of ASU 2014-09 as well as new disclosures required by these amendments; however, the adoption of ASU 2014-09 is not expected to have a material impact on Trustmark’s consolidated financial statements.

Accounting Policies Recently 27

Accounting Policies Recently Adopted and Pending Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Accounting Policies Recently Adopted and Pending Accounting Pronouncements	ASU 2017-08, “ Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities.” Issued in March 2017, ASU 2017-08 amends the amortization period for certain purchased callable debt securities held at a premium. In particular, the amendments in ASU 2017-08 require the premium to be amortized to the earliest call date. The amendments do not, however, require an accounting change for securities held at a discount; instead, the discount continues to be amortized to maturity. Notably, the amendments in this ASU more closely align the amortization period of premiums and discounts to expectations incorporated in market pricing on the underlying securities. Securities within the scope of ASU 2017-08 are purchased debt securities that have explicit, noncontingent call features that are callable at fixed prices and on preset dates. The amendments of ASU 2017-08 become effective for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2018. As of March 31, 2017, Trustmark’s total unamortized premium for purchased debt securities within the scope of ASU 2017-08 was immaterial. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements through its effective date; however, the adoption of ASU 2017-08 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-07, “ Compensation-Retirement Benefits (Topic 715)-Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.” Issued in March 2017, ASU 2017-07 is designed to improve guidance related to the presentation of defined benefit costs in the income statement. In particular, ASU No. 2017-07 requires that an employer report the service cost component in the same line item(s) as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations, if one is presented. If a separate line item or items are used to present the other components of net benefit cost, then that line item or items must be appropriately described. However, if a separate line item or items are not used, then the line item(s) used in the income statement to present the other components of net benefit cost must be disclosed. Additionally, ASU 2017-07 allows only the service cost component to be eligible for capitalization, when applicable. The amendments of ASU 2017-07 become effective for annual periods beginning after December 15, 2017, including interim periods within those annual periods. Management is currently evaluating the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2017-07 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-04, “ Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment.” Issued in January 2017, ASU 2017-04 simplifies the manner in which an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Step 2 measures a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount of that goodwill. In computing the implied fair value of goodwill under Step 2, an entity, prior to the amendments in ASU 2017-04, had to perform procedures to determine the fair value at the impairment testing date of its assets and liabilities, including unrecognized assets and liabilities, in accordance with the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. However, under the amendments in ASU 2017-04, an entity should (1) perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount, and (2) recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value, with the understanding that the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, ASU 2017-04 removes the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment and, if it fails such qualitative test, to perform Step 2 of the goodwill impairment test. ASU 2017-04 is effective prospectively for annual, or any interim, goodwill impairment tests in fiscal years beginning after December 15, 2019. Based on Trustmark’s annual goodwill impairment test performed as of October 1, 2016, the fair value of its reporting units exceeded the carrying value and, therefore, the related goodwill was not impaired. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements through its effective date; however, the adoption of ASU 2017-04 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2017-01, “Business Combinations (Topic 805) - Clarifying the Definition of a Business.” Issued in January 2017, ASU 2017-01 clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses, which determines whether goodwill should be recorded or not. The amendments in ASU No. 2017-01 provide a screen to determine when a set of assets and activities (collectively, a “set”) is not a business. The screen requires that when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. This screen reduces the number of transactions that need to be further evaluated. If, however, the screen is not met, then the amendments in ASU 07-01 require that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and remove the evaluation of whether a market participant could replace missing elements. The revised definition will result in more transactions being recorded as asset acquisitions or dispositions as opposed to business acquisitions or dispositions. The amendments of ASU 2017-01 are effective for interim and annual periods beginning after December 15, 2017. Management is currently evaluating the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2017-01 is not expected to have a material impact Trustmark’s consolidated financial statements. ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.” Issued in August 2016, ASU 2016-15 provides guidance to reduce the diversity in practice of how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The amendments of ASU 2016-15 provide guidance on eight specific cash flow: (i) debt prepayment or debt extinguishment costs; (ii) settlement of zero-coupon bonds; (iii) contingent consideration payments made after a business combination; (iv) proceeds from the settlement of insurance claims; (v) proceeds from the settlement of corporate-owned life insurance policies, including bank-owned life insurance policies; (vi) distributions received from equity method investees; (vii) beneficial interests in securitization transactions and (viii) separately identifiable cash flows and application of the predominance principle. The amendments of ASU 2016-15 are effective for interim and annual periods beginning after December 15, 2017. Trustmark plans to adopt the amendments of ASU 2016-15 during the first quarter of 2018. Management has evaluated the amendments of ASU 2016-15 and does not believe that adoption of this ASU will impact Trustmark’s existing presentation of the applicable cash receipts and cash payments on its consolidated statements of cash flows. ASU 2016-13, “Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” Issued in June 2016, ASU 2016-13 will add FASB ASC Topic 326, “Financial Instruments-Credit Losses” and finalizes amendments to FASB ASC Subtopic 825-15, “Financial Instruments-Credit Losses.” The amendments of ASU 2016-13 are intended to provide financial statement users with more decision-useful information related to expected credit losses on financial instruments and other commitments to extend credit by replacing the current incurred loss impairment methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to determine credit loss estimates. The amendments of ASU 2016-13 eliminate the probable initial recognition threshold and, in turn, reflect an entity’s current estimate of all expected credit losses. ASU 2016-13 does not specify the method for measuring expected credit losses, and an entity is allowed to apply methods that reasonably reflect its expectations of the credit loss estimate. Additionally, the amendments of ASU 2016-13 require that credit losses on available for sale debt securities be presented as an allowance rather than as a write-down. The amendments of ASU 2016-13 are effective for interim and annual periods beginning after December 15, 2019. Earlier application is permitted for interim and annual periods beginning after December 15, 2018. Trustmark plans to adopt the amendments of ASU 2016-13 during the first quarter of 2020. Trustmark has established a steering committee which includes the appropriate members of Management to evaluate the impact this ASU will have on Trustmark’s financial position, results of operations and financial statement disclosures and determine the most appropriate method of implementing the amendments in this ASU as well as any resources needed to implement the amendments. The steering committee is currently evaluating various third-party vendors to determine the most appropriate product for Trustmark and the level of assistance that will be required for implementation. ASU 2016-09, “Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting.” Issued in March 2016, ASU 2016-09 seeks to reduce complexity in accounting standards by simplifying several aspects of the accounting for share-based payment transactions. The amendments of ASU 2016-09 include: (i) requiring all excess tax benefits and tax deficiencies to be recognized as income tax expense or benefit in the income statement; (ii) requiring excess tax benefits to be classified along with other income tax cash flows as an operating activity on the statement of cash flow; (iii) allowing an entity to make an entity-wide accounting policy election to either estimate the number of awards that expect to vest or account for forfeitures when they occur; (iv) change the threshold to qualify for equity classification to permit withholding up to the maximum statutory tax rates in the applicable jurisdictions; and (v) requiring that cash paid by an employer when directly withholding shares for tax-withholding purposes to be classified as a financing activity on the statement of cash flows. The amendments of ASU 2016-09 became effective for Trustmark on January 1, 2017 and did not have a material impact on Trustmark’s consolidated financial statements. Trustmark has made an entity-wide accounting policy election to account for forfeitures of stock awards as they occur. Changes as required by the amendments of ASU 2016-09 are presented in the accompanying consolidated statements of cash flows. ASU 2016-02, “Leases (Topic 842).” Issued in February 2016, ASU 2016-02 was issued by the FASB to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and by disclosing key information about leasing arrangements. ASU 2016-02 will, among other things, require lessees to recognize a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. ASU 2016-02 does not significantly change lease accounting requirements applicable to lessors; however, the ASU contains some targeted improvements that are intended to align, where necessary, lessor accounting with the lessee accounting model and with the updated revenue recognition guidance issued in 2014. The amendments of ASU 2016-02 are effective for interim and annual periods beginning after December 15, 2018. Trustmark plans to adopt the amendments of ASU 2016-02 beginning in the first quarter of 2019. At adoption, Trustmark will recognize a lease asset and a corresponding lease liability on its consolidated balance sheet for its total lease obligation measured on a discounted basis. As of December 31, 2016, all leases in which Trustmark was the lessee were classified as operating leases and the total outstanding lease obligation was $58.0 million, or 0.4% of total assets. Trustmark does not anticipant any material impact to its consolidated statements of income as a result of the adoption of this ASU. Trustmark has an immaterial amount of leases in which it is the lessor. Based on Management’s evaluation to date, Trustmark does not expect the amendments of ASU 2016-02 to have any material impact to these leases or the related income. Management will continue to evaluate the impact this ASU will have on Trustmark’s consolidated financial statements; however, the adoption of ASU 2016-02 is not expected to have a material impact on Trustmark’s consolidated financial statements. ASU 2016-01, “Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (An Amendment of the FASB Accounting Standards Codification).” Issued in January 2016, ASU 2016-01 is intended to enhance the reporting model for financial instruments to provide users of financial statements with improved decision-making information. The amendments of ASU 2016-01 include: (i) requiring equity investments, except those accounted for under the equity method of accounting or those that result in the consolidation of an investee, to be measured at fair value with changes in fair value recognized in net income; (ii) requiring a qualitative assessment to identify impairment of equity investments without readily determinable fair values; (iii) eliminating the requirement to disclose the method and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost on the balance sheet; (iv) requiring the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (v) requiring an entity that has elected the fair value option to measure the fair value of a liability to present separately in other comprehensive income the portion of the change in the fair value resulting from a change in the instrument-specific credit risk; (vi) requiring separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements and (vii) clarifying that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available for sale securities in combination with the entity’s other deferred tax assets. The amendments of ASU 2016-01 are effective for interim and annual periods beginning after December 15, 2017. Trustmark plans to adopt the amendments of ASU 2016-01 during the first quarter of 2018. Management has evaluated the impact this ASU will have on Trustmark’s consolidated financial statements. Through this evaluation, Management has determined that the principal areas impacted by the amendments of ASU 2016-01 will be Trustmark’s investment in member bank stock, which are equity securities that do not have readily determinable fair values, and various fair value related disclosures. See Note 1 – Significant Accounting Policies, “Federal Home Loan Bank (FHLB) and Federal Reserve Bank of Atlanta Stock” included in Item 8 of Trustmark’s Annual Report on Form 10-K for information regarding Trustmark’s investment in member bank stock. The adoption of ASU 2016-01 is not expected to have a material impact on Trustmark’s consolidated financial statements. ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).” Issued in May 2014, ASU 2014-09 will add FASB ASC Topic 606, “Revenue from Contracts with Customers,” and will supersede revenue recognition requirements in FASB ASC Topic 605, “Revenue Recognition,” as well as certain cost guidance in FASB ASC Topic 605-35, “Revenue Recognition – Construction-Type and Production-Type Contracts.” ASU 2014-09 provides a framework for revenue recognition that replaces the existing industry and transaction specific requirements under the existing standards. ASU 2014-09 requires an entity to apply a five-step model to determine when to recognize revenue and at what amount. The model specifies that revenue should be recognized when (or as) an entity transfers control of goods or services to a customer at the amount in which the entity expects to be entitled. Depending on whether certain criteria are met, revenue should be recognized either over time, in a manner that depicts the entity’s performance, or at a point in time, when control of the goods or services are transferred to the customer. ASU 2014-09 provides that an entity should apply the following steps: (1) identify the contract(s) with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when, or as, the entity satisfies a performance obligation. In addition, the existing requirements for the recognition of a gain or loss on the transfer of non-financial assets that are not in a contract with a customer are amended to be consistent with the guidance on recognition and measurement in ASU 2014-09. The amendments of ASU 2014-09 may be applied either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying ASU 2014-09 recognized at the date of initial application. If the transition method of application is elected, the entity should also provide the additional disclosures in reporting periods that include the date of initial application of (1) the amount by which each financial statement line item is affected in the current reporting period, as compared to the guidance that was in effect before the change, and (2) an explanation of the reasons for significant changes. ASU 2015-14, “Revenue from Contracts with Customers (Topic 606)-Deferral of the Effective Date,” issued in August 2015, defers the effective date of ASU 2014-09 by one year. ASU 2015-14 provides that the amendments of ASU 2014-09 become effective for interim and annual periods beginning after December 15, 2017. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. All subsequently issued ASUs which provide additional guidance and clarifications to various aspects of FASB ASC Topic 606 will become effective when the amendments of ASU 2014-09 become effective. Trustmark plans to adopt these amendments during the first quarter of 2018. Management is continuing to evaluate the impact ASU 2014-09 will have on Trustmark’s consolidated financial statements as well as the most appropriate transition method of application. Based on this evaluation to date, Management has determined that the majority of the revenues earned by Trustmark are not within the scope of ASU 2014-09. Management also believes that for most revenue streams within the scope of ASU 2014-09, the amendments will not change the timing of when the revenue is recognized. Management will continue to evaluate the impact the adoption of ASU 2014-09 will have on Trustmark’s consolidated financial statements, focusing on noninterest income sources within the scope of ASU 2014-09 as well as new disclosures required by these amendments; however, the adoption of ASU 2014-09 is not expected to have a material impact on Trustmark’s consolidated financial statements.

Securities Available for Sale28

Securities Available for Sale and Held to Maturity (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 and December 31, 2016 ($ in thousands): Securities Available for Sale Securities Held to Maturity March 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value U.S. Government agency obligations Issued by U.S. Government agencies $ 53,700 $ 376 $ (829 ) $ 53,247 $ — $ — $ — $ — Issued by U.S. Government sponsored agencies 256 18 — 274 3,658 223 — 3,881 Obligations of states and political subdivisions 107,930 2,001 (36 ) 109,895 46,273 1,619 (12 ) 47,880 Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,281 286 (900 ) 42,667 14,977 261 (66 ) 15,172 Issued by FNMA and FHLMC 738,408 1,877 (7,071 ) 733,214 118,733 264 (936 ) 118,061 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,205,842 5,353 (8,476 ) 1,202,719 771,296 2,961 (6,271 ) 767,986 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 223,338 1,197 (997 ) 223,538 201,130 1,420 (1,115 ) 201,435 Total $ 2,372,755 $ 11,108 $ (18,309 ) $ 2,365,554 $ 1,156,067 $ 6,748 $ (8,400 ) $ 1,154,415 December 31, 2016 U.S. Government agency obligations Issued by U.S. Government agencies $ 56,272 $ 416 $ (925 ) $ 55,763 $ — $ — $ — $ — Issued by U.S. Government sponsored agencies 257 19 — 276 3,647 355 — 4,002 Obligations of states and political subdivisions 113,541 1,945 (113 ) 115,373 46,303 1,476 (27 ) 47,752 Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,222 340 (776 ) 42,786 15,478 280 (52 ) 15,706 Issued by FNMA and FHLMC 638,809 1,773 (9,498 ) 631,084 81,299 223 (1,084 ) 80,438 Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,271,198 5,865 (9,112 ) 1,267,951 803,474 3,208 (6,519 ) 800,163 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 242,869 1,766 (1,186 ) 243,449 208,442 1,758 (1,215 ) 208,985 Total $ 2,366,168 $ 12,124 $ (21,610 ) $ 2,356,682 $ 1,158,643 $ 7,300 $ (8,897 ) $ 1,157,046
Securities with Gross Unrealized Losses, Segregated by Length of Impairment	The tables below include securities with gross unrealized losses segregated by length of impairment at March 31, 2017 and December 31, 2016 ($ in thousands): Less than 12 Months 12 Months or More Total March 31, 2017 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses U.S. Government agency obligations Issued by U.S. Government agencies $ 6,941 $ (102 ) $ 34,020 $ (727 ) $ 40,961 $ (829 ) Obligations of states and political subdivisions 9,551 (44 ) 652 (4 ) 10,203 (48 ) Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 42,618 (964 ) 212 (2 ) 42,830 (966 ) Issued by FNMA and FHLMC 598,901 (8,006 ) 46 (1 ) 598,947 (8,007 ) Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,067,305 (11,926 ) 72,596 (2,821 ) 1,139,901 (14,747 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 185,475 (2,111 ) 1,081 (1 ) 186,556 (2,112 ) Total $ 1,910,791 $ (23,153 ) $ 108,607 $ (3,556 ) $ 2,019,398 $ (26,709 ) December 31, 2016 U.S. Government agency obligations Issued by U.S. Government agencies $ 9,420 $ (142 ) $ 33,248 $ (783 ) $ 42,668 $ (925 ) Obligations of states and political subdivisions 20,539 (135 ) 654 (5 ) 21,193 (140 ) Mortgage-backed securities Residential mortgage pass-through securities Guaranteed by GNMA 43,615 (822 ) 222 (6 ) 43,837 (828 ) Issued by FNMA and FHLMC 588,352 (10,582 ) — — 588,352 (10,582 ) Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 1,127,501 (12,722 ) 76,196 (2,909 ) 1,203,697 (15,631 ) Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 244,050 (2,311 ) 4,655 (90 ) 248,705 (2,401 ) Total $ 2,033,477 $ (26,714 ) $ 114,975 $ (3,793 ) $ 2,148,452 $ (30,507 )
Gains and Losses as a Result of Calls and Disposition of Securities	Gains and losses as a result of calls and dispositions of securities, as well as any associated proceeds, were as follows for the periods presented ($ in thousands): Three Months Ended March 31, Available for Sale 2017 2016 Proceeds from calls and sales of securities $ — $ 24,693 Gross realized gains — 32 Gross realized (losses) — (342 )
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, 2017, 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 Available for Sale Securities Held to Maturity Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 31,880 $ 32,032 $ 145 $ 145 Due after one year through five years 85,618 87,786 36,380 37,765 Due after five years through ten years 6,881 6,880 13,406 13,851 Due after ten years 37,507 36,718 — — 161,886 163,416 49,931 51,761 Mortgage-backed securities 2,210,869 2,202,138 1,106,136 1,102,654 Total $ 2,372,755 $ 2,365,554 $ 1,156,067 $ 1,154,415

Loans Held for Investment (LH29

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI (Tables)	3 Months Ended
	Mar. 31, 2017
Accounts Notes Loans And Financing Receivable Gross Allowance And Net [Abstract]
Loan Portfolio Held for Investment	At March 31, 2017 and December 31, 2016, LHFI consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 859,927 $ 831,437 Secured by 1-4 family residential properties 1,656,837 1,660,043 Secured by nonfarm, nonresidential properties 2,064,352 2,034,176 Other real estate secured 399,636 318,148 Commercial and industrial loans 1,540,783 1,528,434 Consumer loans 166,314 170,562 State and other political subdivision loans 910,493 917,515 Other loans 406,315 390,898 LHFI (1) 8,004,657 7,851,213 Less allowance for loan losses, LHFI 72,445 71,265 Net LHFI $ 7,932,212 $ 7,779,948 (1) During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized.
Nonaccrual LHFI by Loan Type	The following table details nonaccrual LHFI by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 2,856 $ 3,323 Secured by 1-4 family residential properties 20,537 20,329 Secured by nonfarm, nonresidential properties 11,492 8,482 Other real estate secured 191 402 Commercial and industrial loans 25,410 15,824 Consumer loans 325 300 State and other political subdivision loans — — Other loans 496 574 Total nonaccrual LHFI $ 61,307 $ 49,234
Aging Analysis of Past Due Loans and Nonaccrual Loans	The following tables provide an aging analysis of past due and nonaccrual LHFI by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Past Due 30-59 Days 60-89 Days 90 Days or (1) Total Nonaccrual Current Loans Total LHFI Loans secured by real estate: Construction, land development and other land $ 504 $ 35 $ 217 $ 756 $ 2,856 $ 856,315 $ 859,927 Secured by 1-4 family residential properties 5,738 1,814 612 8,164 20,537 1,628,136 1,656,837 Secured by nonfarm, nonresidential properties 626 214 — 840 11,492 2,052,020 2,064,352 Other real estate secured 61 — 228 289 191 399,156 399,636 Commercial and industrial loans 813 51 12 876 25,410 1,514,497 1,540,783 Consumer loans 1,495 194 238 1,927 325 164,062 166,314 State and other political subdivision loans — — — — — 910,493 910,493 Other loans 1 40 — 41 496 405,778 406,315 Total $ 9,238 $ 2,348 $ 1,307 $ 12,893 $ 61,307 $ 7,930,457 $ 8,004,657 (1) Past due 90 days or more but still accruing interest. December 31, 2016 Past Due 30-59 Days 60-89 Days 90 Days or (1) Total Nonaccrual Current Loans Total LHFI Loans secured by real estate: Construction, land development and other land $ 248 $ 37 $ 54 $ 339 $ 3,323 $ 827,775 $ 831,437 Secured by 1-4 family residential properties 5,308 2,434 1,436 9,178 20,329 1,630,536 1,660,043 Secured by nonfarm, nonresidential properties 606 100 — 706 8,482 2,024,988 2,034,176 Other real estate secured 179 — — 179 402 317,567 318,148 Commercial and industrial loans 571 213 — 784 15,824 1,511,826 1,528,434 Consumer loans 1,561 330 341 2,232 300 168,030 170,562 State and other political subdivision loans 1,035 — — 1,035 — 916,480 917,515 Other loans 178 53 — 231 574 390,093 390,898 Total $ 9,686 $ 3,167 $ 1,831 $ 14,684 $ 49,234 $ 7,787,295 $ 7,851,213 (1) Past due 90 days or more but still accruing interest.
Impaired Financing Receivables	At March 31, 2017 and December 31, 2016, individually evaluated impaired LHFI consisted of the following ($ in thousands): March 31, 2017 LHFI Unpaid Principal Balance With No Related Allowance Recorded With an Allowance Recorded Total Carrying Amount Related Allowance Average Recorded Investment Loans secured by real estate: Construction, land development and other land $ 4,977 $ 1,661 $ 336 $ 1,997 $ 111 $ 2,219 Secured by 1-4 family residential properties 6,351 203 4,589 4,792 1,357 4,720 Secured by nonfarm, nonresidential properties 11,512 6,438 2,753 9,191 852 7,705 Other real estate secured — — — — — — Commercial and industrial loans 23,343 13,130 9,877 23,007 1,562 18,338 Consumer loans 1 — 1 1 — 2 State and other political subdivision loans — — — — — — Other loans 95 95 — 95 — 95 Total $ 46,279 $ 21,527 $ 17,556 $ 39,083 $ 3,882 $ 33,079 December 31, 2016 LHFI Unpaid Principal Balance With No Related Allowance Recorded With an Allowance Recorded Total Carrying Amount Related Allowance Average Recorded Investment Loans secured by real estate: Construction, land development and other land $ 5,691 $ 2,260 $ 181 $ 2,441 $ 103 $ 2,943 Secured by 1-4 family residential properties 6,134 221 4,428 4,649 960 4,639 Secured by nonfarm, nonresidential properties 8,562 5,784 435 6,219 221 6,703 Other real estate secured — — — — — 500 Commercial and industrial loans 14,593 11,461 2,208 13,669 1,976 14,258 Consumer loans 2 — 2 2 — 2 State and other political subdivision loans — — — — — — Other loans 95 95 — 95 — 95 Total $ 35,077 $ 19,821 $ 7,254 $ 27,075 $ 3,260 $ 29,140
Impact of Modifications Classified as Troubled Debt Restructurings	The following tables illustrate the impact of modifications classified as TDRs as well as those TDRs modified within the last 12 months for which there was a payment default during the period for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Troubled Debt Restructurings Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Construction, land development and other land loans 1 $ 341 $ 325 — $ — $ — Loans secured by 1-4 family residential properties 7 334 338 2 71 71 Total 8 $ 675 $ 663 2 $ 71 $ 71
Troubled Debt Restructuring Subsequently Defaulted	Three Months Ended March 31, 2017 2016 TDRs that Subsequently Defaulted Number of Contracts Recorded Investment Number of Contracts Recorded Investment Loans secured by 1-4 family residential properties 1 $ — 1 $ 17 Commercial and industrial 2 — — — Total 3 $ — 1 $ 17
Troubled Debt Restructuring Related to Loans Held for Investment by Loan Type	The following tables detail LHFI classified as TDRs by loan type at March 31, 2017 and 2016 ($ in thousands): March 31, 2017 Accruing Nonaccrual Total Loans secured by real estate: Construction, land development and other land $ — $ 642 $ 642 Secured by 1-4 family residential properties — 3,070 3,070 Secured by nonfarm, nonresidential properties — 841 841 Commercial and industrial loans — 7,845 7,845 Consumer loans — 1 1 Total TDRs $ — $ 12,399 $ 12,399 March 31, 2016 Accruing Nonaccrual Total Loans secured by real estate: Construction, land development and other land $ — $ 845 $ 845 Secured by 1-4 family residential properties 1,444 2,086 3,530 Secured by nonfarm, nonresidential properties 799 3,566 4,365 Commercial and industrial loans — 448 448 Total TDRs $ 2,243 $ 6,945 $ 9,188
Carrying Amount of Loans by Credit Quality Indicator	The tables below present LHFI by loan type and credit quality indicator at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Commercial LHFI Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 790,145 $ — $ 6,567 $ 463 $ 797,175 Secured by 1-4 family residential properties 129,742 219 6,610 210 136,781 Secured by nonfarm, nonresidential properties 2,012,125 9,172 41,597 760 2,063,654 Other real estate secured 388,398 9,938 680 — 399,016 Commercial and industrial loans 1,390,084 18,807 130,806 1,086 1,540,783 Consumer loans — — — — — State and other political subdivision loans 893,139 6,450 10,904 — 910,493 Other loans 399,144 — 2,609 347 402,100 Total $ 6,002,777 $ 44,586 $ 199,773 $ 2,866 $ 6,250,002 Consumer LHFI Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual Subtotal Total LHFI Loans secured by real estate: Construction, land development and other land $ 62,185 $ 446 $ — $ 121 $ 62,752 $ 859,927 Secured by 1-4 family residential properties 1,495,639 6,638 612 17,167 1,520,056 1,656,837 Secured by nonfarm, nonresidential properties 698 — — — 698 2,064,352 Other real estate secured 620 — — — 620 399,636 Commercial and industrial loans — — — — — 1,540,783 Consumer loans 164,063 1,689 238 324 166,314 166,314 State and other political subdivision loans — — — — — 910,493 Other loans 4,175 40 — — 4,215 406,315 Total $ 1,727,380 $ 8,813 $ 850 $ 17,612 $ 1,754,655 $ 8,004,657 December 31, 2016 Commercial LHFI Pass - Categories 1-6 Special Mention - Category 7 Substandard Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 752,318 $ 9,567 $ 8,086 $ 465 $ 770,436 Secured by 1-4 family residential properties 124,615 170 6,162 129 131,076 Secured by nonfarm, nonresidential properties 1,989,554 4,394 38,913 584 2,033,445 Other real estate secured 315,829 762 890 — 317,481 Commercial and industrial loans 1,386,155 7,095 134,199 985 1,528,434 Consumer loans — — — — — State and other political subdivision loans 899,935 6,450 11,130 — 917,515 Other loans 382,890 — 2,685 350 385,925 Total $ 5,851,296 $ 28,438 $ 202,065 $ 2,513 $ 6,084,312 Consumer LHFI Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual Subtotal Total LHFI Loans secured by real estate: Construction, land development and other land $ 60,701 $ 188 $ 54 $ 58 $ 61,001 $ 831,437 Secured by 1-4 family residential properties 1,503,096 7,377 1,436 17,058 1,528,967 1,660,043 Secured by nonfarm, nonresidential properties 731 — — — 731 2,034,176 Other real estate secured 667 — — — 667 318,148 Commercial and industrial loans — — — — — 1,528,434 Consumer loans 168,031 1,891 341 299 170,562 170,562 State and other political subdivision loans — — — — — 917,515 Other loans 4,940 33 — — 4,973 390,898 Total $ 1,738,166 $ 9,489 $ 1,831 $ 17,415 $ 1,766,901 $ 7,851,213
Change in Allowance for Loan Losses	The following tables detail the balance in the allowance for loan losses, LHFI allocated to each loan type segmented by the impairment evaluation methodology used at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Individually Collectively Total Loans secured by real estate: Construction, land development and other land $ 111 $ 8,415 $ 8,526 Secured by 1-4 family residential properties 1,357 9,430 10,787 Secured by nonfarm, nonresidential properties 852 21,056 21,908 Other real estate secured — 3,139 3,139 Commercial and industrial loans 1,562 20,089 21,651 Consumer loans — 3,192 3,192 State and other political subdivision loans — 848 848 Other loans — 2,394 2,394 Total allowance for loan losses, LHFI $ 3,882 $ 68,563 $ 72,445 December 31, 2016 Individually Collectively Total Loans secured by real estate: Construction, land development and other land loans $ 103 $ 8,982 $ 9,085 Secured by 1-4 family residential properties 960 9,387 10,347 Secured by nonfarm, nonresidential properties 221 20,746 20,967 Other real estate secured — 2,263 2,263 Commercial and industrial loans 1,976 20,035 22,011 Consumer loans — 3,241 3,241 State and other political subdivision loans — 859 859 Other loans — 2,492 2,492 Total allowance for loan losses, LHFI $ 3,260 $ 68,005 $ 71,265 Changes in the allowance for loan losses, LHFI were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 71,265 $ 67,619 Loans charged-off (4,202 ) (3,363 ) Recoveries 2,620 3,169 Net charge-offs (1,582 ) (194 ) Provision for loan losses, LHFI 2,762 2,243 Balance at end of period $ 72,445 $ 69,668 The following tables detail changes in the allowance for loan losses, LHFI by loan type for the periods ended March 31, 2017 and 2016 ($ in thousands): 2017 Balance January 1, Charge-offs Recoveries Provision for Loan Losses Balance March 31, Loans secured by real estate: Construction, land development and other land $ 9,085 $ (58 ) $ 303 $ (804 ) $ 8,526 Secured by 1-4 family residential properties 10,347 (241 ) 152 529 10,787 Secured by nonfarm, nonresidential properties 20,967 — 182 759 21,908 Other real estate secured 2,263 — 20 856 3,139 Commercial and industrial loans 22,011 (1,984 ) 488 1,136 21,651 Consumer loans 3,241 (745 ) 480 216 3,192 State and other political subdivision loans 859 — — (11 ) 848 Other loans 2,492 (1,174 ) 995 81 2,394 Total allowance for loan losses, LHFI $ 71,265 $ (4,202 ) $ 2,620 $ 2,762 $ 72,445 2016 Balance January 1, Charge-offs Recoveries Provision for Loan Losses Balance March 31, Loans secured by real estate: Construction, land development and other land loans $ 11,587 $ — $ 492 $ (1,937 ) $ 10,142 Secured by 1-4 family residential properties 10,678 (692 ) 457 30 10,473 Secured by nonfarm, nonresidential properties 21,563 (27 ) 119 2,052 23,707 Other real estate secured 2,467 — 1 (395 ) 2,073 Commercial and industrial loans 15,815 (770 ) 123 2,481 17,649 Consumer loans 2,879 (484 ) 1,010 (601 ) 2,804 State and other political subdivision loans 809 — — 7 816 Other loans 1,821 (1,390 ) 967 606 2,004 Total allowance for loan losses, LHFI $ 67,619 $ (3,363 ) $ 3,169 $ 2,243 $ 69,668
Summary Of LHFI Evaluated For Impairment	The following tables detail LHFI by loan type related to each balance in the allowance for loan losses, LHFI segregated by the impairment evaluation methodology used at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 LHFI Evaluated for Impairment Individually Collectively Total Loans secured by real estate: Construction, land development and other land $ 1,997 $ 857,930 $ 859,927 Secured by 1-4 family residential properties 4,792 1,652,045 1,656,837 Secured by nonfarm, nonresidential properties 9,191 2,055,161 2,064,352 Other real estate secured — 399,636 399,636 Commercial and industrial loans 23,007 1,517,776 1,540,783 Consumer loans 1 166,313 166,314 State and other political subdivision loans — 910,493 910,493 Other loans 95 406,220 406,315 Total $ 39,083 $ 7,965,574 $ 8,004,657 December 31, 2016 LHFI Evaluated for Impairment Individually Collectively Total Loans secured by real estate: Construction, land development and other land $ 2,441 $ 828,996 $ 831,437 Secured by 1-4 family residential properties 4,649 1,655,394 1,660,043 Secured by nonfarm, nonresidential properties 6,219 2,027,957 2,034,176 Other real estate secured — 318,148 318,148 Commercial and industrial loans 13,669 1,514,765 1,528,434 Consumer loans 2 170,560 170,562 State and other political subdivision loans — 917,515 917,515 Other loans 95 390,803 390,898 Total $ 27,075 $ 7,824,138 $ 7,851,213

Acquired Loans (Tables)

Acquired Loans (Tables)	3 Months Ended
	Mar. 31, 2017
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities [Abstract]
Schedule of Acquired Loans	At March 31, 2017 and December 31, 2016, acquired loans consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Loans secured by real estate: Construction, land development and other land $ 17,651 $ 20,850 Secured by 1-4 family residential properties 54,721 69,540 Secured by nonfarm, nonresidential properties 92,075 103,820 Other real estate secured 16,275 19,010 Commercial and industrial loans 20,691 36,896 Consumer loans 2,664 3,365 Other loans 14,165 18,766 Acquired loans 218,242 272,247 Less allowance for loan losses, acquired loans 10,006 11,397 Net acquired loans $ 208,236 $ 260,850
Changes in the Carrying Value of Acquired Loans	The following table presents changes in the net carrying value of the acquired loans for the periods presented ($ in thousands): Acquired Impaired Acquired Not ASC 310-30 (1) Carrying value, net at January 1, 2016 $ 310,762 $ 67,657 Accretion to interest income 18,405 40 Payments received, net (111,522 ) (24,953 ) Other (2) (134 ) — Less change in allowance for loan losses, acquired loans 596 (1 ) Carrying value, net at December 31, 2016 218,107 42,743 Transfers (3) — (36,719 ) Accretion to interest income 3,673 — Payments received, net (14,645 ) (6,024 ) Other (2) (290 ) — Less change in allowance for loan losses, acquired loans 1,391 — Carrying value, net at March 31, 2017 $ 208,236 $ — (1) "Acquired Not ASC 310-30" loans consist of revolving credit agreements and commercial leases that are not in scope for FASB ASC Topic 310-30, "Loans and Debt Securities Acquired with Deteriorated Credit Quality." (2) Includes miscellaneous timing adjustments as well as acquired loan terminations through foreclosure, charge-off and other terminations. (3) During the first quarter of 2017, Trustmark transferred the remaining balance of the “Acquired Not ASC 310-30” loans to LHFI due to the discount on these loans being fully amortized.
Changes in Accretable Yield of Acquired Loans	The following table presents changes in the accretable yield for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Accretable yield at beginning of period $ (38,918 ) $ (52,672 ) Accretion to interest income 3,673 5,230 (Additions)/disposals (183 ) 1,067 Reclassification from nonaccretable difference (1) (1,788 ) (3,403 ) Accretable yield at end of period $ (37,216 ) $ (49,778 ) (1) Reclassifications from nonaccretable difference are due to lower loss expectations and improvements in expected cash flows.
Components of the Allowance for Loan Losses on Acquired Loans	The following tables present the components of the allowance for loan losses on acquired loans for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 11,397 $ 11,992 Provision for loan losses, acquired loans (1,605 ) 1,309 Loans charged-off — (397 ) Recoveries 214 631 Net recoveries 214 234 Balance at end of period $ 10,006 $ 13,535
Acquired Loans by Loan Type and Credit Quality Indicator	The tables below present the acquired loans by loan type and credit quality indicator at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Commercial Loans Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 11,322 $ 93 $ 4,130 $ 522 $ 16,067 Secured by 1-4 family residential properties 12,649 52 3,573 52 16,326 Secured by nonfarm, nonresidential properties 73,125 — 18,389 515 92,029 Other real estate secured 12,775 — 2,536 544 15,855 Commercial and industrial loans 12,354 18 7,202 1,117 20,691 Consumer loans — — — — — Other loans 8,613 — 5,432 117 14,162 Total acquired loans $ 130,838 $ 163 $ 41,262 $ 2,867 $ 175,130 Consumer Loans Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual (1) Subtotal Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 1,469 $ 102 $ 13 $ — $ 1,584 $ 17,651 Secured by 1-4 family residential properties 36,509 1,500 386 — 38,395 54,721 Secured by nonfarm, nonresidential properties 46 — — — 46 92,075 Other real estate secured 420 — — — 420 16,275 Commercial and industrial loans — — — — — 20,691 Consumer loans 2,603 58 3 — 2,664 2,664 Other loans 3 — — — 3 14,165 Total acquired loans $ 41,050 $ 1,660 $ 402 $ — $ 43,112 $ 218,242 (1) Acquired loans not accounted for under FASB ASC Topic 310-30. December 31, 2016 Commercial Loans Pass - Categories 1-6 Special Mention - Category 7 Substandard - Category 8 Doubtful - Category 9 Subtotal Loans secured by real estate: Construction, land development and other land $ 12,148 $ 99 $ 6,469 $ 322 $ 19,038 Secured by 1-4 family residential properties 14,552 61 4,066 69 18,748 Secured by nonfarm, nonresidential properties 83,271 435 19,553 511 103,770 Other real estate secured 15,344 — 2,673 565 18,582 Commercial and industrial loans 22,024 18 13,494 1,354 36,890 Consumer loans — — — — — Other loans 12,954 — 5,649 161 18,764 Total acquired loans $ 160,293 $ 613 $ 51,904 $ 2,982 $ 215,792 Consumer Loans Current Past Due 30-89 Days Past Due 90 Days or More Nonaccrual (1) Subtotal Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 1,801 $ — $ 11 $ — $ 1,812 $ 20,850 Secured by 1-4 family residential properties 48,695 1,364 709 24 50,792 69,540 Secured by nonfarm, nonresidential properties 50 — — — 50 103,820 Other real estate secured 428 — — — 428 19,010 Commercial and industrial loans 6 — — — 6 36,896 Consumer loans 3,250 51 64 — 3,365 3,365 Other loans 2 — — — 2 18,766 Total acquired loans $ 54,232 $ 1,415 $ 784 $ 24 $ 56,455 $ 272,247 (1) Acquired loans not accounted for under FASB ASC Topic 310-30.
Aging Analysis of Past Due and Nonaccrual Acquired Loans, by Class	The following tables provide an aging analysis of contractually past due and nonaccrual acquired loans by loan type at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 Past Due 30-59 Days 60-89 Days 90 Days or More (1) Total Nonaccrual (2) Current Loans Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 102 $ 176 $ 1,513 $ 1,791 $ — $ 15,860 $ 17,651 Secured by 1-4 family residential properties 1,568 625 683 2,876 — 51,845 54,721 Secured by nonfarm, nonresidential properties 166 1,739 1,850 3,755 — 88,320 92,075 Other real estate secured — — 576 576 — 15,699 16,275 Commercial and industrial loans 18 — 5 23 — 20,668 20,691 Consumer loans 58 — 3 61 — 2,603 2,664 Other loans — — — — — 14,165 14,165 Total acquired loans $ 1,912 $ 2,540 $ 4,630 $ 9,082 $ — $ 209,160 $ 218,242 (1) Past due 90 days or more but still accruing interest. (2) Acquired loans not accounted for under FASB ASC Topic 310-30. December 31, 2016 Past Due 30-59 Days 60-89 Days 90 Days or More (1) Total Nonaccrual (2) Current Loans Total Acquired Loans Loans secured by real estate: Construction, land development and other land $ 321 $ 100 $ 821 $ 1,242 $ — $ 19,608 $ 20,850 Secured by 1-4 family residential properties 1,495 412 1,057 2,964 41 66,535 69,540 Secured by nonfarm, nonresidential properties 1,658 38 343 2,039 328 101,453 103,820 Other real estate secured 769 — 1,445 2,214 — 16,796 19,010 Commercial and industrial loans 60 39 — 99 262 36,535 36,896 Consumer loans 51 — 64 115 — 3,250 3,365 Other loans — — — — — 18,766 18,766 Total acquired loans $ 4,354 $ 589 $ 3,730 $ 8,673 $ 631 $ 262,943 $ 272,247 (1) Past due 90 days or more but still accruing interest. (2) Acquired loans not accounted for under FASB ASC Topic 310-30.

Mortgage Banking (Tables)

Mortgage Banking (Tables)	3 Months Ended
	Mar. 31, 2017
Mortgage Banking [Abstract]
Schedule of Activity in the Mortgage Servicing Rights	The activity in the mortgage servicing rights (MSR) is detailed in the table below for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 80,239 $ 74,007 Origination of servicing assets 3,440 3,072 Change in fair value: Due to market changes 1,466 (6,866 ) Due to run-off (2,387 ) (2,005 ) Balance at end of period $ 82,758 $ 68,208
Schedule of Mortgage Loans Sold and Serviced for Others	The table below details the mortgage loans sold and serviced for others at March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Federal National Mortgage Association $ 4,033,540 $ 3,992,349 Government National Mortgage Association 2,307,321 2,291,398 Federal Home Loan Mortgage Corporation 53,377 55,006 Other 30,264 32,589 Total mortgage loans sold and serviced for others $ 6,424,502 $ 6,371,342
Changes in the Reserve for Mortgage Loan Servicing Putback Expense	Changes in the reserve for mortgage loan servicing putback expense for mortgage loans were as follows for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Balance at beginning of period $ 1,130 $ 1,685 Provision for putback expenses 105 105 Gains (losses) 16 (5 ) Balance at end of period $ 1,251 $ 1,785

Other Real Estate (Tables)

Other Real Estate (Tables)	3 Months Ended
	Mar. 31, 2017
Other Real Estate And Foreclosed Assets [Abstract]
Changes and Gains, Net on Other Real Estate	For the periods presented, changes and gains, net on other real estate were as follows ($ in thousands): Three Months Ended March 31, 2017 2016 (1) Balance at beginning of period $ 62,051 $ 78,828 Additions 1,766 3,608 Disposals (6,385 ) (8,994 ) Write-downs (1,464 ) (1,140 ) Balance at end of period $ 55,968 $ 72,302 Gain, net on the sale of other real estate included in other real estate expense $ 470 $ 1,868 (1) The changes and gains, net on other real estate for the three months ended March 31, 2016 include covered other real estate.
Other Real Estate, By Type of Property	At March 31, 2017 and December 31, 2016, other real estate by type of property consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Construction, land development and other land properties $ 35,256 $ 36,871 1-4 family residential properties 6,818 7,926 Nonfarm, nonresidential properties 13,457 16,817 Other real estate properties 437 437 Total other real estate $ 55,968 $ 62,051
Other Real Estate, By Geographic Location	At March 31, 2017 and December 31, 2016, other real estate by geographic location consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Alabama $ 13,953 $ 15,989 Florida 21,577 22,582 Mississippi (1) 14,974 15,646 Tennessee (2) 4,706 6,183 Texas 758 1,651 Total other real estate $ 55,968 $ 62,051 (1) Mississippi includes Central and Southern Mississippi Regions (2) Tennessee includes Memphis, Tennessee and Northern Mississippi Regions

Deposits (Tables)

Deposits (Tables)	3 Months Ended
	Mar. 31, 2017
Deposits [Abstract]
Deposits Summary	At March 31, 2017 and December 31, 2016, deposits consisted of the following ($ in thousands): March 31, 2017 December 31, 2016 Noninterest-bearing demand $ 3,209,727 $ 2,973,238 Interest-bearing demand 1,927,415 1,875,312 Savings 3,295,565 3,586,369 Time 1,671,765 1,621,093 Total $ 10,104,472 $ 10,056,012

Securities Sold Under Repurch34

Securities Sold Under Repurchase Agreements (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Mortgage-backed securities Other residential mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA $ 87,525 $ 75,795 Commercial mortgage-backed securities Issued or guaranteed by FNMA, FHLMC or GNMA 51,691 51,212 Total securities sold under repurchase agreements $ 139,216 $ 127,007

Defined Benefit and Other Pos35

Defined Benefit and Other Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2017
Trustmark Capital Accumulation Plan [Member]
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost for Plan and Spin-Off Plan	The following table presents information regarding the net periodic benefit cost for the Plan and the Spin-Off Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Service cost $ 63 $ 108 Interest cost 665 830 Expected return on plan assets (108 ) (1,022 ) Recognized net loss due to lump sum settlements — 423 Recognized net actuarial loss 565 661 Net periodic benefit cost $ 1,185 $ 1,000
Supplemental Retirement Plan [Member]
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Benefit Cost for Plan and Spin-Off Plan	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, 2017 2016 Service cost $ 35 $ 74 Interest cost 561 546 Amortization of prior service cost 63 63 Recognized net actuarial loss 222 221 Net periodic benefit cost $ 881 $ 904

Stock and Incentive Compensat36

Stock and Incentive Compensation Plans (Tables)	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Plan Activity	The following table summarizes the Stock Plan activity for the periods presented: Three Months Ended March 31, 2017 Performance Awards Time-Vested Awards Nonvested shares, beginning of period 237,136 322,056 Granted 58,406 88,224 Released from restriction (62,601 ) (83,862 ) Forfeited (2,947 ) (734 ) Nonvested shares, end of period 229,994 325,684
Compensation Expense for Awards Under Stock Plan	The following table presents information regarding compensation expense for awards under the Stock Plan for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Performance awards $ 105 $ 100 Time-vested awards 848 861 Total compensation expense $ 953 $ 961

Earnings Per Share (EPS) (Table

Earnings Per Share (EPS) (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 Basic shares 67,687 67,610 Dilutive shares 159 137 Diluted shares 67,846 67,747
Weighted-Average Antidilutive Stock Awards Excluded from Determining Diluted EPS	Weighted-average antidilutive stock awards were excluded in determining diluted EPS. The following table reflects weighted-average antidilutive stock awards for the periods presented (in thousands): Three Months Ended March 31, 2017 2016 Weighted-average antidilutive stock awards 43 —

Statements of Cash Flows (Table

Statements of Cash Flows (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 Income taxes paid $ 778 $ 376 Interest expense paid on deposits and borrowings 7,190 4,986 Noncash transfers from loans to other real estate (1) 1,766 3,608 (1) Includes transfers from covered loans to covered other real estate.

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 and December 31, 2016 ($ in thousands): Actual Regulatory Capital Minimum To Be Well Amount Ratio Requirement Capitalized At March 31, 2017: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,223,078 12.19 % 5.750 % n/a Trustmark National Bank 1,266,309 12.63 % 5.750 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,282,919 12.79 % 7.250 % n/a Trustmark National Bank 1,266,309 12.63 % 7.250 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,365,370 13.61 % 9.250 % n/a Trustmark National Bank 1,348,760 13.45 % 9.250 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,282,919 9.86 % 4.00 % n/a Trustmark National Bank 1,266,309 9.75 % 4.00 % 5.00 % At December 31, 2016: Common Equity Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,209,927 12.16 % 5.125 % n/a Trustmark National Bank 1,251,329 12.58 % 5.125 % 6.50 % Tier 1 Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,269,660 12.76 % 6.625 % n/a Trustmark National Bank 1,251,329 12.58 % 6.625 % 8.00 % Total Capital (to Risk Weighted Assets) Trustmark Corporation $ 1,352,322 13.59 % 8.625 % n/a Trustmark National Bank 1,333,991 13.41 % 8.625 % 10.00 % Tier 1 Leverage (to Average Assets) Trustmark Corporation $ 1,269,660 9.90 % 4.00 % n/a Trustmark National Bank 1,251,329 9.77 % 4.00 % 5.00 %
Components of Accumulated Other Comprehensive Income (Loss) and the Related Tax Effects	Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 Before Tax Amount Tax (Expense) Benefit Net of Tax Amount Before Tax Amount Tax (Expense) Benefit Net of Tax Amount Securities available for sale and transferred securities: Unrealized holding gains arising during the period $ 2,285 $ (874 ) $ 1,411 $ 35,343 $ (13,518 ) $ 21,825 Reclassification adjustment for net losses realized in net income — — — 310 (119 ) 191 Change in net unrealized holding loss on securities transferred to held to maturity 1,232 (471 ) 761 2,724 (1,042 ) 1,682 Total securities available for sale and transferred securities 3,517 (1,345 ) 2,172 38,377 (14,679 ) 23,698 Pension and other postretirement benefit plans: Net change in prior service costs 63 (24 ) 39 62 (24 ) 38 Recognized net loss due to lump sum settlements — — — 423 (162 ) 261 Change in net actuarial loss 787 (301 ) 486 882 (337 ) 545 Total pension and other postretirement benefit plans 850 (325 ) 525 1,367 (523 ) 844 Cash flow hedge derivatives: Change in accumulated gain (loss) on effective cash flow hedge derivatives 57 (22 ) 35 (1,328 ) 508 (820 ) Reclassification adjustment for loss realized in net income 99 (38 ) 61 160 (61 ) 99 Total cash flow hedge derivatives 156 (60 ) 96 (1,168 ) 447 (721 ) Total other comprehensive income $ 4,523 $ (1,730 ) $ 2,793 $ 38,576 $ (14,755 ) $ 23,821
Components of Reclassifications Out of Accumulated Other Comprehensive Income (Loss)	The following table presents the changes in the balances of each component of accumulated other comprehensive loss for the periods presented ($ in thousands). All amounts are presented net of tax. Securities Available and Transferred Securities Defined Benefit Pension Items Cash Flow Hedge Derivatives Total Balance at January 1, 2017 $ (20,800 ) $ (24,980 ) $ (18 ) $ (45,798 ) Other comprehensive income before reclassification 2,172 — 35 2,207 Amounts reclassified from accumulated other comprehensive loss — 525 61 586 Net other comprehensive income 2,172 525 96 2,793 Balance at March 31, 2017 $ (18,628 ) $ (24,455 ) $ 78 $ (43,005 ) Balance at January 1, 2016 $ (17,394 ) $ (27,840 ) $ (160 ) $ (45,394 ) Other comprehensive income (loss) before reclassification 23,507 — (820 ) 22,687 Amounts reclassified from accumulated other comprehensive loss 191 844 99 1,134 Net other comprehensive income (loss) 23,698 844 (721 ) 23,821 Balance at March 31, 2016 $ 6,304 $ (26,996 ) $ (881 ) $ (21,573 )

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2017
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 as of March 31, 2017 and December 31, 2016, 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, 2017 and the year ended December 31, 2016. March 31, 2017 Total Level 1 Level 2 Level 3 U.S. Government agency obligations $ 53,521 $ — $ 53,521 $ — Obligations of states and political subdivisions 109,895 — 109,895 — Mortgage-backed securities 2,202,138 — 2,202,138 — Securities available for sale 2,365,554 — 2,365,554 — Loans held for sale 174,090 — 174,090 — Mortgage servicing rights 82,758 — — 82,758 Other assets - derivatives 4,230 521 1,564 2,145 Other liabilities - derivatives 3,676 909 2,767 — December 31, 2016 Total Level 1 Level 2 Level 3 U.S. Government agency obligations $ 56,039 $ — $ 56,039 $ — Obligations of states and political subdivisions 115,373 — 115,373 — Mortgage-backed securities 2,185,270 — 2,185,270 — Securities available for sale 2,356,682 — 2,356,682 — Loans held for sale 175,927 — 175,927 — Mortgage servicing rights 80,239 — — 80,239 Other assets - derivatives 2,518 (524 ) 2,041 1,001 Other liabilities - derivatives 412 1,174 (762 ) —
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, 2017 and 2016 are summarized as follows ($ in thousands): MSR Other Assets - Derivatives Balance, January 1, 2017 $ 80,239 $ 1,001 Total net (loss) gain included in Mortgage banking, net (1) (921 ) 1,955 Additions 3,440 — Sales — (811 ) Balance, March 31, 2017 $ 82,758 $ 2,145 The amount of total gains for the period included in earnings that are attributable to the change in unrealized gains or losses still held at March 31, 2017 $ 1,466 $ 342 Balance, January 1, 2016 $ 74,007 $ 1,113 Total net (loss) gain included in Mortgage banking, net (1) (8,871 ) 3,097 Additions 3,072 — Sales — (926 ) Balance, March 31, 2016 $ 68,208 $ 3,284 The amount of total (losses) gains for the period included in earnings that are attributable to the change in unrealized gains or losses still held at March 31, 2016 $ (6,866 ) $ 398 (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, 2017 and December 31, 2016, are as follows ($ in thousands): March 31, 2017 December 31, 2016 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial Assets: Level 2 Inputs: Cash and short-term investments $ 380,090 $ 380,090 $ 328,206 $ 328,206 Securities held to maturity 1,156,067 1,154,415 1,158,643 1,157,046 Level 3 Inputs: Net LHFI 7,932,212 8,001,968 7,779,948 7,825,009 Net acquired loans 208,236 208,236 260,850 260,850 Financial Liabilities: Level 2 Inputs: Deposits 10,104,472 10,105,262 10,056,012 10,059,794 Short-term liabilities 1,389,025 1,389,025 1,309,595 1,309,595 Long-term FHLB advances 250,994 250,994 251,049 251,050 Junior subordinated debt securities 61,856 43,299 61,856 41,057
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 the LHFS accounted for under the fair value option as of March 31, 2017 and December 31, 2016 ($ in thousands): March 31, 2017 December 31, 2016 Fair value of LHFS $ 135,170 $ 132,002 LHFS contractual principal outstanding 131,632 132,047 Fair value less unpaid principal $ 3,538 $ (45 )

Derivative Financial Instrume41

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2017
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 as of March 31, 2017 and December 31, 2016 as well as the effect of these derivative instruments on Trustmark’s results of operations for the periods presented ($ in thousands): March 31, 2017 December 31, 2016 Derivatives in hedging relationships Interest rate contracts: Interest rate swaps included in other assets $ 127 $ (28 ) Derivatives not designated as hedging instruments Interest rate contracts: Futures contracts included in other assets $ 299 $ (626 ) Exchange traded purchased options included in other assets 222 102 OTC written options (rate locks) included in other assets 2,145 1,001 Interest rate swaps included in other assets 1,431 2,060 Credit risk participation agreements included in other assets 6 9 Forward contracts included in other liabilities 1,175 (2,838 ) Exchange traded written options included in other liabilities 909 1,174 Interest rate swaps included in other liabilities 1,584 2,065 Credit risk participation agreements included in other liabilities 8 11
Effects of Derivative Instruments on Statements of Operations	Three Months Ended March 31, 2017 2016 Derivatives in hedging relationships Amount of loss reclassified from accumulated other comprehensive loss and recognized in other interest expense $ (99 ) $ (160 ) Derivatives not designated as hedging instruments Amount of (loss) gain recognized in mortgage banking, net $ (1,544 ) $ 7,139 Amount of loss recognized in bank card and other fees (28 ) (58 )
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, net of tax, for derivative instruments designated as cash flow hedges for the periods presented ($ in thousands): Three Months Ended March 31, 2017 2016 Derivatives in cash flow hedging relationship Amount of gain (loss) recognized in other comprehensive income, net of tax $ 35 $ (820 )
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, 2017 and December 31, 2016 is presented in the following tables ($ in thousands): Offsetting of Derivative Assets As of March 31, 2017 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets presented in the Statement of Financial Position Financial Instruments Cash Collateral Received Net Amount Derivatives $ 1,558 $ — $ 1,558 $ (182 ) $ — $ 1,376 Offsetting of Derivative Liabilities As of March 31, 2017 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Liabilities presented in the Statement of Financial Position Financial Instruments Cash Collateral Posted Net Amount Derivatives $ 1,584 $ — $ 1,584 $ (182 ) $ (100 ) $ 1,302 Offsetting of Derivative Assets As of December 31, 2016 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets presented in the Statement of Financial Position Financial Instruments Cash Collateral Received Net Amount Derivatives $ 2,032 $ — $ 2,032 $ (499 ) $ — $ 1,533 Offsetting of Derivative Liabilities As of December 31, 2016 Gross Amounts Not Offset in the Statement of Financial Position Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Liabilities presented in the Statement of Financial Position Financial Instruments Cash Collateral Posted Net Amount Derivatives $ 2,065 $ — $ 2,065 $ (499 ) $ (937 ) $ 629

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2017
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, 2017 2016 General Banking Net interest income $ 97,411 $ 94,442 Provision for loan losses, net 1,157 3,552 Noninterest income 29,440 27,394 Noninterest expense 87,357 85,893 Income before income taxes 38,337 32,391 Income taxes 8,369 7,319 General banking net income $ 29,968 $ 25,072 Selected Financial Information Total assets $ 13,417,229 $ 12,701,364 Depreciation and amortization $ 8,836 $ 8,485 Wealth Management Net interest income $ 129 $ 245 Noninterest income 7,377 7,288 Noninterest expense 7,201 5,891 Income before income taxes 305 1,642 Income taxes 116 628 Wealth management net income $ 189 $ 1,014 Selected Financial Information Total assets $ 7,279 $ 7,329 Depreciation and amortization $ 37 $ 44 Insurance Net interest income $ 50 $ 53 Noninterest income 9,216 8,594 Noninterest expense 7,499 7,160 Income before income taxes 1,767 1,487 Income taxes 676 570 Insurance net income $ 1,091 $ 917 Selected Financial Information Total assets $ 65,853 $ 66,503 Depreciation and amortization $ 158 $ 192 Consolidated Net interest income $ 97,590 $ 94,740 Provision for loan losses, net 1,157 3,552 Noninterest income 46,033 43,276 Noninterest expense 102,057 98,944 Income before income taxes 40,409 35,520 Income taxes 9,161 8,517 Consolidated net income $ 31,248 $ 27,003 Selected Financial Information Total assets $ 13,490,361 $ 12,775,196 Depreciation and amortization $ 9,031 $ 8,721

Business, Basis of Financial 43

Business, Basis of Financial Statement Presentation and Principles of Consolidation (Details)	Mar. 31, 2017Office
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of offices	193

Business Combinations - Additio

Business Combinations - Additional Information (Details) - RB Bancorporation [Member] $ / shares in Units, $ in Millions	Apr. 07, 2017USD ($)Office	Mar. 31, 2017USD ($)	Nov. 14, 2016$ / shares
Business Acquisition [Line Items]
Assets		$ 201.2
Business acquisition, share price | $ / shares			$ 22
Subsequent Event [Member]
Business Acquisition [Line Items]
Number of offices | Office	7
Business acquisition agreement date	Nov. 14, 2016
Total consideration	$ 23.7
One-time expenses related to the merger to be incurred	$ 3
Fair value measurement period from acquisition date, maximum	1 year

Securities Available for Sale45

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, 2017	Dec. 31, 2016
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 2,372,755	$ 2,366,168
Securities Available for Sale, Gross Unrealized Gains	11,108	12,124
Securities Available for Sale, Gross Unrealized (Losses)	(18,309)	(21,610)
Securities Available for Sale, Estimated Fair Value	2,365,554	2,356,682
Securities Held to Maturity, Amortized Cost	1,156,067	1,158,643
Securities Held to Maturity, Gross Unrealized Gains	6,748	7,300
Securities Held to Maturity, Gross Unrealized (Losses)	(8,400)	(8,897)
Securities Held to Maturity, Estimated Fair Value	1,154,415	1,157,046
U.S. Government Agency Obligations Issued by U.S. Government Agencies [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	53,700	56,272
Securities Available for Sale, Gross Unrealized Gains	376	416
Securities Available for Sale, Gross Unrealized (Losses)	(829)	(925)
Securities Available for Sale, Estimated Fair Value	53,247	55,763
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
U.S. Government Agency Obligations Issued by U.S. Government Sponsored Agencies [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Securities Available for Sale, Amortized Cost	256	257
Securities Available for Sale, Gross Unrealized Gains	18	19
Securities Available for Sale, Gross Unrealized (Losses)	0	0
Securities Available for Sale, Estimated Fair Value	274	276
Securities Held to Maturity, Amortized Cost	3,658	3,647
Securities Held to Maturity, Gross Unrealized Gains	223	355
Securities Held to Maturity, Gross Unrealized (Losses)	0	0
Securities Held to Maturity, Estimated Fair Value	3,881	4,002
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	107,930	113,541
Securities Available for Sale, Gross Unrealized Gains	2,001	1,945
Securities Available for Sale, Gross Unrealized (Losses)	(36)	(113)
Securities Available for Sale, Estimated Fair Value	109,895	115,373
Securities Held to Maturity, Amortized Cost	46,273	46,303
Securities Held to Maturity, Gross Unrealized Gains	1,619	1,476
Securities Held to Maturity, Gross Unrealized (Losses)	(12)	(27)
Securities Held to Maturity, Estimated Fair Value	47,880	47,752
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	43,281	43,222
Securities Available for Sale, Gross Unrealized Gains	286	340
Securities Available for Sale, Gross Unrealized (Losses)	(900)	(776)
Securities Available for Sale, Estimated Fair Value	42,667	42,786
Securities Held to Maturity, Amortized Cost	14,977	15,478
Securities Held to Maturity, Gross Unrealized Gains	261	280
Securities Held to Maturity, Gross Unrealized (Losses)	(66)	(52)
Securities Held to Maturity, Estimated Fair Value	15,172	15,706
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	738,408	638,809
Securities Available for Sale, Gross Unrealized Gains	1,877	1,773
Securities Available for Sale, Gross Unrealized (Losses)	(7,071)	(9,498)
Securities Available for Sale, Estimated Fair Value	733,214	631,084
Securities Held to Maturity, Amortized Cost	118,733	81,299
Securities Held to Maturity, Gross Unrealized Gains	264	223
Securities Held to Maturity, Gross Unrealized (Losses)	(936)	(1,084)
Securities Held to Maturity, Estimated Fair Value	118,061	80,438
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	1,205,842	1,271,198
Securities Available for Sale, Gross Unrealized Gains	5,353	5,865
Securities Available for Sale, Gross Unrealized (Losses)	(8,476)	(9,112)
Securities Available for Sale, Estimated Fair Value	1,202,719	1,267,951
Securities Held to Maturity, Amortized Cost	771,296	803,474
Securities Held to Maturity, Gross Unrealized Gains	2,961	3,208
Securities Held to Maturity, Gross Unrealized (Losses)	(6,271)	(6,519)
Securities Held to Maturity, Estimated Fair Value	767,986	800,163
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	223,338	242,869
Securities Available for Sale, Gross Unrealized Gains	1,197	1,766
Securities Available for Sale, Gross Unrealized (Losses)	(997)	(1,186)
Securities Available for Sale, Estimated Fair Value	223,538	243,449
Securities Held to Maturity, Amortized Cost	201,130	208,442
Securities Held to Maturity, Gross Unrealized Gains	1,420	1,758
Securities Held to Maturity, Gross Unrealized (Losses)	(1,115)	(1,215)
Securities Held to Maturity, Estimated Fair Value	$ 201,435	$ 208,985

Securities Available for Sale46

Securities Available for Sale and Held to Maturity - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]
Reclassification of Securities available for sale to securities held to maturity				$ 1,099,000,000
Net unrealized holding loss on AFS Securities at date of transfer				46,600,000
Net unrealized holding losses on AFS Securities, net of tax at date of transfer				$ 28,800,000
Net unamortized, unrealized loss on transfer of securities	$ 23,000,000
Net unamortized, unrealized loss on transfer of securities, net of tax	14,200,000
Other-than-temporary impairments	0	$ 0
Pledged to collateralize public deposits and securities sold under repurchase agreements and for other purposes as permitted by law	1,990,000,000		$ 1,999,000,000
Pledged securities providing additional contingency funding	$ 0		$ 0

Securities Available for Sale47

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, 2017	Dec. 31, 2016
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	$ 1,910,791	$ 2,033,477
Estimated Fair Value, 12 Months or More	108,607	114,975
Estimated Fair Value, Total	2,019,398	2,148,452
Gross Unrealized (Losses), Less than 12 Months	(23,153)	(26,714)
Gross Unrealized (Losses), 12 Months or More	(3,556)	(3,793)
Gross Unrealized (Losses), Total	(26,709)	(30,507)
U.S. Government Agency Obligations Issued by U.S. Government Agencies [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	6,941	9,420
Estimated Fair Value, 12 Months or More	34,020	33,248
Estimated Fair Value, Total	40,961	42,668
Gross Unrealized (Losses), Less than 12 Months	(102)	(142)
Gross Unrealized (Losses), 12 Months or More	(727)	(783)
Gross Unrealized (Losses), Total	(829)	(925)
Obligations of States and Political Subdivisions [Member]
Schedule of Available For Sale and Held to Maturity Securities [Line Items]
Estimated Fair Value, Less than 12 Months	9,551	20,539
Estimated Fair Value, 12 Months or More	652	654
Estimated Fair Value, Total	10,203	21,193
Gross Unrealized (Losses), Less than 12 Months	(44)	(135)
Gross Unrealized (Losses), 12 Months or More	(4)	(5)
Gross Unrealized (Losses), Total	(48)	(140)
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	42,618	43,615
Estimated Fair Value, 12 Months or More	212	222
Estimated Fair Value, Total	42,830	43,837
Gross Unrealized (Losses), Less than 12 Months	(964)	(822)
Gross Unrealized (Losses), 12 Months or More	(2)	(6)
Gross Unrealized (Losses), Total	(966)	(828)
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	598,901	588,352
Estimated Fair Value, 12 Months or More	46	0
Estimated Fair Value, Total	598,947	588,352
Gross Unrealized (Losses), Less than 12 Months	(8,006)	(10,582)
Gross Unrealized (Losses), 12 Months or More	(1)	0
Gross Unrealized (Losses), Total	(8,007)	(10,582)
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	1,067,305	1,127,501
Estimated Fair Value, 12 Months or More	72,596	76,196
Estimated Fair Value, Total	1,139,901	1,203,697
Gross Unrealized (Losses), Less than 12 Months	(11,926)	(12,722)
Gross Unrealized (Losses), 12 Months or More	(2,821)	(2,909)
Gross Unrealized (Losses), Total	(14,747)	(15,631)
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	185,475	244,050
Estimated Fair Value, 12 Months or More	1,081	4,655
Estimated Fair Value, Total	186,556	248,705
Gross Unrealized (Losses), Less than 12 Months	(2,111)	(2,311)
Gross Unrealized (Losses), 12 Months or More	(1)	(90)
Gross Unrealized (Losses), Total	$ (2,112)	$ (2,401)

Securities Available for Sale48

Securities Available for Sale and Held to Maturity - Gains and Losses as a Result of Calls and Disposition of Securities (Details) - Available for Sale [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Gains (losses) on Investments [Abstract]
Proceeds from calls and sales of securities	$ 0	$ 24,693
Gross realized gains	0	32
Gross realized (losses)	$ 0	$ (342)

Securities Available for Sale49

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, 2017	Dec. 31, 2016
Securities Available for Sale, Amortized Cost [Abstract]
Due in one year or less	$ 31,880
Due after one year through five years	85,618
Due after five years through ten years	6,881
Due after ten years	37,507
Total amortized cost, before mortgage-backed securities	161,886
Mortgage-backed securities	2,210,869
Total	2,372,755
Securities Available for Sale, Estimated Fair Value [Abstract]
Due in one year or less	32,032
Due after one year through five years	87,786
Due after five years through ten years	6,880
Due after ten years	36,718
Total fair value, before mortgage-backed securities	163,416
Mortgage-backed securities	2,202,138
Total	2,365,554	$ 2,356,682
Securities Held to Maturity, Amortized Cost [Abstract]
Due in one year or less	145
Due after one year through five years	36,380
Due after five years through ten years	13,406
Due after ten years	0
Total amortized cost, before mortgage-backed securities	49,931
Mortgage-backed securities	1,106,136
Securities Held to Maturity, Amortized Cost	1,156,067	1,158,643
Securities Held to Maturity, Estimated Fair Value [Abstract]
Due in one year or less	145
Due after one year through five years	37,765
Due after five years through ten years	13,851
Due after ten years	0
Total fair value, before mortgage-backed securities	51,761
Mortgage-backed securities	1,102,654
Total	$ 1,154,415	$ 1,157,046

Loans Held for Investment (LH50

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Loan Portfolio Held for Investment (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Loan Portfolio [Abstract]
Total LHFI	[1]	$ 8,004,657	$ 7,851,213
Less allowance for loan losses, LHFI		72,445	71,265
Net LHFI		7,932,212	7,779,948
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI		859,927	831,437
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI		1,656,837	1,660,043
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI		399,636	318,148
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI		2,064,352	2,034,176
Commercial and Industrial Loans [Member]
Loan Portfolio [Abstract]
Total LHFI		1,540,783	1,528,434
Consumer Loans [Member]
Loan Portfolio [Abstract]
Total LHFI		166,314	170,562
State and Other Political Subdivision Loans [Member]
Loan Portfolio [Abstract]
Total LHFI		910,493	917,515
Other Loans [Member]
Loan Portfolio [Abstract]
Total LHFI		$ 406,315	$ 390,898
[1]	During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized.

Loans Held for Investment (LH51

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Loan Portfolio Held for Investment (Parenthetical) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
Accounts Notes Loans And Financing Receivable Gross Allowance And Net [Abstract]
Reclassification of acquired loans	$ 36.7

Loans Held for Investment (LH52

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Additional Information (Details 1)	3 Months Ended
	Mar. 31, 2017USD ($)Region	Mar. 31, 2016USD ($)	Jan. 01, 2017USD ($)	Dec. 31, 2016USD ($)
Financing Receivable Impaired [Line Items]
Maximum concentration of loan as a percentage of total LHFI	10.00%
Key market regions | Region	5
Carrying amounts of nonaccrual LHFI considered for impairment analysis	$ 61,300,000			$ 49,200,000
Nonaccrual	61,307,000			49,234,000
Minimum loan amount for loan to be specifically reviewed for impairment and deemed impaired			$ 500,000
Amount held by company of foreclosure or in substance repossession of consumer mortgage LHFI classified as TDRs	234,000			269,000
TDRs Classified as Consumer mortgage LHFI in the process of formal disclosure	107,000			101,000
LHFI Classified as TDRs	12,400,000	$ 9,200,000
LHFI classified as TDRs from credits with interest only payments	9,500,000	5,700,000
Financing receivable, related allowance	382,000	1,700,000
Financing receivable, related charge-offs	0	0
Troubled Debt Restructurings [Member]
Financing Receivable Impaired [Line Items]
Nonaccrual	$ 12,399,000	$ 6,945,000		$ 14,400,000

Loans Held for Investment (LH53

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Nonaccrual LHFI by Loan Type (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loan Portfolio [Abstract]
Total nonaccrual LHFI	$ 61,307	$ 49,234
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	2,856	3,323
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	20,537	20,329
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	11,492	8,482
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	191	402
Commercial and Industrial Loans [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	25,410	15,824
Consumer Loans [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	325	300
Other Loans [Member]
Loan Portfolio [Abstract]
Total nonaccrual LHFI	$ 496	$ 574

Loans Held for Investment (LH54

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Aging Analysis of Past Due Loans and Nonaccrual Loans, Excluding Covered Loans by Loan Type (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		$ 12,893	$ 14,684
Nonaccrual		61,307	49,234
Current Loans		7,930,457	7,787,295
Total LHFI	[1]	8,004,657	7,851,213
Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		9,238	9,686
Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		2,348	3,167
Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	1,307	1,831
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		756	339
Nonaccrual		2,856	3,323
Current Loans		856,315	827,775
Total LHFI		859,927	831,437
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		504	248
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		35	37
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	217	54
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		8,164	9,178
Nonaccrual		20,537	20,329
Current Loans		1,628,136	1,630,536
Total LHFI		1,656,837	1,660,043
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		5,738	5,308
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		1,814	2,434
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	612	1,436
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		840	706
Nonaccrual		11,492	8,482
Current Loans		2,052,020	2,024,988
Total LHFI		2,064,352	2,034,176
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		626	606
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		214	100
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		289	179
Nonaccrual		191	402
Current Loans		399,156	317,567
Total LHFI		399,636	318,148
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		61	179
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	228
Commercial and Industrial Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		876	784
Nonaccrual		25,410	15,824
Current Loans		1,514,497	1,511,826
Total LHFI		1,540,783	1,528,434
Commercial and Industrial Loans [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		813	571
Commercial and Industrial Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		51	213
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	12
Consumer Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		1,927	2,232
Nonaccrual		325	300
Current Loans		164,062	168,030
Total LHFI		166,314	170,562
Consumer Loans [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		1,495	1,561
Consumer Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		194	330
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	[2]	238	341
State and Other Political Subdivision Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due			1,035
Current Loans		910,493	916,480
Total LHFI		910,493	917,515
State and Other Political Subdivision Loans [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due			1,035
Other Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		41	231
Nonaccrual		496	574
Current Loans		405,778	390,093
Total LHFI		406,315	390,898
Other Loans [Member] | Past Due 30 to 59 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		1	178
Other Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due		$ 40	$ 53
[1]	During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized.
[2]	Past due 90 days or more but still accruing interest.

Loans Held for Investment (LH55

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	$ 46,279	$ 35,077
Total LHFI With No Related Allowance Recorded	21,527	19,821
Total LHFI With an Allowance Recorded	17,556	7,254
Total LHFI Carrying Amount	39,083	27,075
Related Allowance	3,882	3,260
Average Recorded Investment	33,079	29,140
Commercial and Industrial Loans [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	23,343	14,593
Total LHFI With No Related Allowance Recorded	13,130	11,461
Total LHFI With an Allowance Recorded	9,877	2,208
Total LHFI Carrying Amount	23,007	13,669
Related Allowance	1,562	1,976
Average Recorded Investment	18,338	14,258
Consumer Loans [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	1	2
Total LHFI With No Related Allowance Recorded	0	0
Total LHFI With an Allowance Recorded	1	2
Total LHFI Carrying Amount	1	2
Related Allowance	0	0
Average Recorded Investment	2	2
State and Other Political Subdivision Loans [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	0	0
Total LHFI With No Related Allowance Recorded	0	0
Total LHFI With an Allowance Recorded	0	0
Total LHFI Carrying Amount	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Other Loans [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	95	95
Total LHFI With No Related Allowance Recorded	95	95
Total LHFI With an Allowance Recorded	0	0
Total LHFI Carrying Amount	95	95
Related Allowance	0	0
Average Recorded Investment	95	95
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	4,977	5,691
Total LHFI With No Related Allowance Recorded	1,661	2,260
Total LHFI With an Allowance Recorded	336	181
Total LHFI Carrying Amount	1,997	2,441
Related Allowance	111	103
Average Recorded Investment	2,219	2,943
Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	6,351	6,134
Total LHFI With No Related Allowance Recorded	203	221
Total LHFI With an Allowance Recorded	4,589	4,428
Total LHFI Carrying Amount	4,792	4,649
Related Allowance	1,357	960
Average Recorded Investment	4,720	4,639
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	11,512	8,562
Total LHFI With No Related Allowance Recorded	6,438	5,784
Total LHFI With an Allowance Recorded	2,753	435
Total LHFI Carrying Amount	9,191	6,219
Related Allowance	852	221
Average Recorded Investment	7,705	6,703
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Loan and Lease Receivables, Impaired [Abstract]
Total LHFI Unpaid Principal Balance	0	0
Total LHFI With No Related Allowance Recorded	0	0
Total LHFI With an Allowance Recorded	0	0
Total LHFI Carrying Amount	0	0
Related Allowance	0	0
Average Recorded Investment	$ 0	$ 500

Loans Held for Investment (LH56

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Impact of Modifications Classified as Troubled Debt Restructurings (Details) - Troubled Debt Restructurings [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)Contract	Mar. 31, 2016USD ($)Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	8	2
Pre-Modification Outstanding Recorded Investment	$ 675	$ 71
Post-Modification Outstanding Recorded Investment	$ 663	$ 71
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	7	2
Pre-Modification Outstanding Recorded Investment	$ 334	$ 71
Post-Modification Outstanding Recorded Investment	$ 338	$ 71
Construction, Land Development and Other Land Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1
Pre-Modification Outstanding Recorded Investment	$ 341
Post-Modification Outstanding Recorded Investment	$ 325

Loans Held for Investment (LH57

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings that Subsequently Defaulted [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)Contract	Mar. 31, 2016USD ($)Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	3	1
Recorded Investment | $	$ 0	$ 17
Commercial and Industrial [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	2	0
Recorded Investment | $	$ 0	$ 0
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1	1
Recorded Investment | $	$ 0	$ 17

Loans Held for Investment (LH58

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Related to Loans Held for Investment, Excluding Covered Loans, by Loan Type (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Financing Receivable Modifications [Line Items]
Nonaccrual	$ 61,307	$ 49,234
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	2,856	3,323
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	20,537	20,329
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	11,492	8,482
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	25,410	15,824
Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	325	300
Troubled Debt Restructurings [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		$ 2,243
Nonaccrual	12,399	$ 14,400	6,945
Total	12,399		9,188
Troubled Debt Restructurings [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		0
Nonaccrual	642		845
Total	642		845
Troubled Debt Restructurings [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		1,444
Nonaccrual	3,070		2,086
Total	3,070		3,530
Troubled Debt Restructurings [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		799
Nonaccrual	841		3,566
Total	841		4,365
Troubled Debt Restructurings [Member] | Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		0
Nonaccrual	7,845		448
Total	7,845		$ 448
Troubled Debt Restructurings [Member] | Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Accruing	0
Nonaccrual	1
Total	$ 1

Loans Held for Investment (LH59

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Additional Information (Details 2)	3 Months Ended
	Mar. 31, 2017USD ($)KeyRatioLoanPoolCreditRiskGrade	Dec. 31, 2016USD ($)
Financing Receivable, Recorded Investment, Aging [Abstract]
Number of days used as baseline in evaluating collateral documentation exceptions for loan policy	90 days
Number of key quality ratios | KeyRatio	6
LHFS past due 90 days or more	$ 31,100,000	$ 28,300,000
Percentage of outstanding principal to be repurchased under GNMA optional repurchase program	100.00%
Financing Receivable [Abstract]
Number of primary commercial loan groups | LoanPool	9
Number of individual credit risk grades | CreditRiskGrade	10
Minimum [Member]
Financing Receivable [Abstract]
Period to conduct asset review	6 months
Credit amount used as baseline in evaluating loan policy	$ 100,000
Maximum [Member]
Financing Receivable [Abstract]
Period to conduct asset review	18 months

Loans Held for Investment (LH60

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Summary of LHFI by Loan Type and Credit Quality Indicator (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Financing Receivable [Abstract]
Current		$ 7,930,457	$ 7,787,295
Financing Receivable, Recorded Investment, Past Due		12,893	14,684
Nonaccrual		61,307	49,234
Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	1,307	1,831
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Current		856,315	827,775
Financing Receivable, Recorded Investment, Past Due		756	339
Nonaccrual		2,856	3,323
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	217	54
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Current		1,628,136	1,630,536
Financing Receivable, Recorded Investment, Past Due		8,164	9,178
Nonaccrual		20,537	20,329
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	612	1,436
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Current		2,052,020	2,024,988
Financing Receivable, Recorded Investment, Past Due		840	706
Nonaccrual		11,492	8,482
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Current		399,156	317,567
Financing Receivable, Recorded Investment, Past Due		289	179
Nonaccrual		191	402
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	228
Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Current		1,514,497	1,511,826
Financing Receivable, Recorded Investment, Past Due		876	784
Nonaccrual		25,410	15,824
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	12
Consumer Loans [Member]
Financing Receivable [Abstract]
Current		164,062	168,030
Financing Receivable, Recorded Investment, Past Due		1,927	2,232
Nonaccrual		325	300
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due	[1]	238	341
State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Current		910,493	916,480
Financing Receivable, Recorded Investment, Past Due			1,035
Other Loans [Member]
Financing Receivable [Abstract]
Current		405,778	390,093
Financing Receivable, Recorded Investment, Past Due		41	231
Nonaccrual		496	574
Commercial LHFI [Member]
Financing Receivable [Abstract]
Financing receivable commercial		6,250,002	6,084,312
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		797,175	770,436
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		136,781	131,076
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		2,063,654	2,033,445
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		399,016	317,481
Commercial LHFI [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		1,540,783	1,528,434
Commercial LHFI [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		910,493	917,515
Commercial LHFI [Member] | Other Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		402,100	385,925
Commercial LHFI [Member] | Pass [Member]
Financing Receivable [Abstract]
Financing receivable commercial		6,002,777	5,851,296
Commercial LHFI [Member] | Pass [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		790,145	752,318
Commercial LHFI [Member] | Pass [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		129,742	124,615
Commercial LHFI [Member] | Pass [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		2,012,125	1,989,554
Commercial LHFI [Member] | Pass [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		388,398	315,829
Commercial LHFI [Member] | Pass [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		1,390,084	1,386,155
Commercial LHFI [Member] | Pass [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		893,139	899,935
Commercial LHFI [Member] | Pass [Member] | Other Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		399,144	382,890
Commercial LHFI [Member] | Special Mention [Member]
Financing Receivable [Abstract]
Financing receivable commercial		44,586	28,438
Commercial LHFI [Member] | Special Mention [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial			9,567
Commercial LHFI [Member] | Special Mention [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		219	170
Commercial LHFI [Member] | Special Mention [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		9,172	4,394
Commercial LHFI [Member] | Special Mention [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		9,938	762
Commercial LHFI [Member] | Special Mention [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		18,807	7,095
Commercial LHFI [Member] | Special Mention [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		6,450	6,450
Commercial LHFI [Member] | Substandard [Member]
Financing Receivable [Abstract]
Financing receivable commercial		199,773	202,065
Commercial LHFI [Member] | Substandard [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		6,567	8,086
Commercial LHFI [Member] | Substandard [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		6,610	6,162
Commercial LHFI [Member] | Substandard [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		41,597	38,913
Commercial LHFI [Member] | Substandard [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		680	890
Commercial LHFI [Member] | Substandard [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		130,806	134,199
Commercial LHFI [Member] | Substandard [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		10,904	11,130
Commercial LHFI [Member] | Substandard [Member] | Other Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		2,609	2,685
Commercial LHFI [Member] | Doubtful [Member]
Financing Receivable [Abstract]
Financing receivable commercial		2,866	2,513
Commercial LHFI [Member] | Doubtful [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		463	465
Commercial LHFI [Member] | Doubtful [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		210	129
Commercial LHFI [Member] | Doubtful [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		760	584
Commercial LHFI [Member] | Doubtful [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		1,086	985
Commercial LHFI [Member] | Doubtful [Member] | Other Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		347	350
Consumer LHFI [Member]
Financing Receivable [Abstract]
Financing receivable commercial		8,004,657	7,851,213
Current		1,727,380	1,738,166
Nonaccrual		17,612	17,415
Subtotal		1,754,655	1,766,901
Consumer LHFI [Member] | Past Due 30-89 Days [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		8,813	9,489
Consumer LHFI [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		850	1,831
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		859,927	831,437
Current		62,185	60,701
Nonaccrual		121	58
Subtotal		62,752	61,001
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		446	188
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due			54
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		1,656,837	1,660,043
Current		1,495,639	1,503,096
Nonaccrual		17,167	17,058
Subtotal		1,520,056	1,528,967
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		6,638	7,377
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		612	1,436
Consumer LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		2,064,352	2,034,176
Current		698	731
Subtotal		698	731
Consumer LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable [Abstract]
Financing receivable commercial		399,636	318,148
Current		620	667
Subtotal		620	667
Consumer LHFI [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		1,540,783	1,528,434
Consumer LHFI [Member] | Consumer Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		166,314	170,562
Current		164,063	168,031
Nonaccrual		324	299
Subtotal		166,314	170,562
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 30-89 Days [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		1,689	1,891
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		238	341
Consumer LHFI [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		910,493	917,515
Consumer LHFI [Member] | Other Loans [Member]
Financing Receivable [Abstract]
Financing receivable commercial		406,315	390,898
Current		4,175	4,940
Subtotal		4,215	4,973
Consumer LHFI [Member] | Other Loans [Member] | Past Due 30-89 Days [Member]
Financing Receivable [Abstract]
Financing Receivable, Recorded Investment, Past Due		$ 40	$ 33
[1]	Past due 90 days or more but still accruing interest.

Loans Held for Investment (LH61

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Additional Information (Details 3)	3 Months Ended
	Mar. 31, 2017LoanFactorScale
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Number of loan types for commercial portfolio | Loan	9
Number of risk rate factors for commercial loans | Factor	450
Minimum score for qualitative risk factor | Scale	0
Maximum score for qualitative risk factor | Scale	100
Number of loan types for consumer portfolio | Loan	5
Number of unique qualitative factors used to analyze consumer loans | Factor	5

Loans Held for Investment (LH62

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Total	$ 72,445	$ 71,265
Allowance for Loan Losses, LHFI [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	3,882	3,260
Collectively	68,563	68,005
Total	72,445	71,265	$ 69,668	$ 67,619
Allowance for Loan Losses, LHFI [Member] | Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	1,562	1,976
Collectively	20,089	20,035
Total	21,651	22,011	17,649	15,815
Allowance for Loan Losses, LHFI [Member] | Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively	3,192	3,241
Total	3,192	3,241	2,804	2,879
Allowance for Loan Losses, LHFI [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually		0
Collectively	848	859
Total	848	859	816	809
Allowance for Loan Losses, LHFI [Member] | Other Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively	2,394	2,492
Total	2,394	2,492	2,004	1,821
Allowance for Loan Losses, LHFI [Member] | Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	111	103
Collectively	8,415	8,982
Total	8,526	9,085	10,142	11,587
Allowance for Loan Losses, LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	1,357	960
Collectively	9,430	9,387
Total	10,787	10,347	10,473	10,678
Allowance for Loan Losses, LHFI [Member] | Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	852	221
Collectively	21,056	20,746
Total	21,908	20,967	23,707	21,563
Allowance for Loan Losses, LHFI [Member] | Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively	3,139	2,263
Total	$ 3,139	$ 2,263	$ 2,073	$ 2,467

Loans Held for Investment (LH63

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Summary of Loan Type Related to Each Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		$ 39,100	$ 27,100
Total LHFI	[1]	8,004,657	7,851,213
Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		39,083	27,075
LHFI, Collectively Evaluated For Impairment		7,965,574	7,824,138
Total LHFI		8,004,657	7,851,213
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		859,927	831,437
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		1,997	2,441
LHFI, Collectively Evaluated For Impairment		857,930	828,996
Total LHFI		859,927	831,437
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		1,656,837	1,660,043
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		4,792	4,649
LHFI, Collectively Evaluated For Impairment		1,652,045	1,655,394
Total LHFI		1,656,837	1,660,043
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		2,064,352	2,034,176
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		9,191	6,219
LHFI, Collectively Evaluated For Impairment		2,055,161	2,027,957
Total LHFI		2,064,352	2,034,176
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		399,636	318,148
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Collectively Evaluated For Impairment		399,636	318,148
Total LHFI		399,636	318,148
Commercial and Industrial Loans [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		1,540,783	1,528,434
Commercial and Industrial Loans [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		23,007	13,669
LHFI, Collectively Evaluated For Impairment		1,517,776	1,514,765
Total LHFI		1,540,783	1,528,434
Consumer Loans [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		166,314	170,562
Consumer Loans [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		1	2
LHFI, Collectively Evaluated For Impairment		166,313	170,560
Total LHFI		166,314	170,562
State and Other Political Subdivision Loans [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		910,493	917,515
State and Other Political Subdivision Loans [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Collectively Evaluated For Impairment		910,493	917,515
Total LHFI		910,493	917,515
Other Loans [Member]
Loans and Leases Receivable, Other Information [Abstract]
Total LHFI		406,315	390,898
Other Loans [Member] | Allowance for Loan Losses, LHFI [Member]
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment		95	95
LHFI, Collectively Evaluated For Impairment		406,220	390,803
Total LHFI		$ 406,315	$ 390,898
[1]	During the first quarter of 2017, Trustmark reclassified $36.7 million of acquired loans not accounted for under Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 310-30, “Loans and Debt Securities Acquired with Deteriorated Credit Quality” to LHFI due to the discount on these loans being fully amortized.

Loans Held for Investment (LH64

Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Change in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 71,265
Provision for loan losses, LHFI	2,762	$ 2,243
Balance at end of period	72,445
Allowance for Loan Losses, LHFI [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	71,265	67,619
Loans charged-off	(4,202)	(3,363)
Recoveries	2,620	3,169
Net charge-offs	(1,582)	(194)
Provision for loan losses, LHFI	2,762	2,243
Balance at end of period	72,445	69,668
Allowance for Loan Losses, LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	9,085	11,587
Loans charged-off	(58)
Recoveries	303	492
Provision for loan losses, LHFI	(804)	(1,937)
Balance at end of period	8,526	10,142
Allowance for Loan Losses, LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	10,347	10,678
Loans charged-off	(241)	(692)
Recoveries	152	457
Provision for loan losses, LHFI	529	30
Balance at end of period	10,787	10,473
Allowance for Loan Losses, LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	20,967	21,563
Loans charged-off		(27)
Recoveries	182	119
Provision for loan losses, LHFI	759	2,052
Balance at end of period	21,908	23,707
Allowance for Loan Losses, LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	2,263	2,467
Recoveries	20	1
Provision for loan losses, LHFI	856	(395)
Balance at end of period	3,139	2,073
Allowance for Loan Losses, LHFI [Member] | Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	22,011	15,815
Loans charged-off	(1,984)	(770)
Recoveries	488	123
Provision for loan losses, LHFI	1,136	2,481
Balance at end of period	21,651	17,649
Allowance for Loan Losses, LHFI [Member] | Consumer Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	3,241	2,879
Loans charged-off	(745)	(484)
Recoveries	480	1,010
Provision for loan losses, LHFI	216	(601)
Balance at end of period	3,192	2,804
Allowance for Loan Losses, LHFI [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	859	809
Provision for loan losses, LHFI	(11)	7
Balance at end of period	848	816
Allowance for Loan Losses, LHFI [Member] | Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	2,492	1,821
Loans charged-off	(1,174)	(1,390)
Recoveries	995	967
Provision for loan losses, LHFI	81	606
Balance at end of period	$ 2,394	$ 2,004

Acquired Loans - Schedule of Ac

Acquired Loans - Schedule of Acquired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	$ 218,242	$ 272,247
Less allowance for loan losses, acquired loans	10,006	11,397	$ 13,535	$ 11,992
Net acquired loans	208,236	260,850
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	17,651	20,850
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	54,721	69,540
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	92,075	103,820
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	16,275	19,010
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	20,691	36,896
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	2,664	3,365
Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	$ 14,165	$ 18,766

Acquired Loans - Changes in the

Acquired Loans - Changes in the Carrying Value of Acquired Loans (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Carrying value of acquired loans [Abstract]
Carrying value, net, beginning		$ 260,850
Accretion to interest income		3,673	$ 5,230
Carrying value, net, ending		208,236		$ 260,850
Acquired Not ASC 310-30 [Member]
Carrying value of acquired loans [Abstract]
Carrying value, net, beginning	[1]	42,743	67,657	67,657
Accretion to interest income	[1]	0		40
Payments received, net	[1]	(6,024)		(24,953)
Other	[1],[2]	0		0
Less change in allowance for loan losses, acquired loans	[1]	0		(1)
Carrying value, net, ending	[1]	0		42,743
Transfers	[1],[3]	(36,719)
Acquired Impaired [Member]
Carrying value of acquired loans [Abstract]
Carrying value, net, beginning		218,107	$ 310,762	310,762
Accretion to interest income		3,673		18,405
Payments received, net		(14,645)		(111,522)
Other	[2]	(290)		(134)
Less change in allowance for loan losses, acquired loans		1,391		596
Carrying value, net, ending		208,236		$ 218,107
Transfers	[3]	$ 0
[1]	"Acquired Not ASC 310-30" loans consist of revolving credit agreements and commercial leases that are not in scope for FASB ASC Topic 310-30, "Loans and Debt Securities Acquired with Deteriorated Credit Quality."
[2]	Includes miscellaneous timing adjustments as well as acquired loan terminations through foreclosure, charge-off and other terminations.
[3]	During the first quarter of 2017, Trustmark transferred the remaining balance of the “Acquired Not ASC 310-30” loans to LHFI due to the discount on these loans being fully amortized.

Acquired Loans - Changes in Acc

Acquired Loans - Changes in Accretable Yield of Acquired Loans (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Change in accretable difference on acquired loans [Abstract]
Accretable yield at beginning of period		$ (38,918)	$ (52,672)	$ (52,672)
Accretion to interest income		3,673	5,230
(Additions)/disposals		(183)	1,067
Reclassification from nonaccretable difference	[1]	(1,788)	(3,403)
Accretable yield at end of period		$ (37,216)	$ (49,778)	$ (38,918)
[1]	Reclassifications from nonaccretable difference are due to lower loss expectations and improvements in expected cash flows.

Acquired Loans - Components of

Acquired Loans - Components of the Allowance for Loan Losses on Acquired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 11,397	$ 11,992
Provision for loan losses, acquired loans	(1,605)	1,309
Loans charged-off		(397)
Recoveries	214	631
Net recoveries	214	234
Balance at end of period	$ 10,006	$ 13,535

Acquired Loans - Additional Inf

Acquired Loans - Additional Information (Details)	3 Months Ended
	Mar. 31, 2017USD ($)CreditRiskGrade	Dec. 31, 2016USD ($)
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities [Abstract]
Number of individual credit risk grades | CreditRiskGrade	10
Nonaccrual loans not accounted for under FASB ASC Topic 310 30 | $	$ 0	$ 631,000

Acquired Loans - Acquired Loans

Acquired Loans - Acquired Loans by Loan Type and Credit Quality Indicator (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		$ 208,236	$ 260,850
Acquired Loans, Aging [Abstract]
Current		209,160	262,943
Acquired Loans, Past Due		9,082	8,673
Nonaccrual	[1]	0	631
Total Acquired Loans		218,242	272,247
Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	4,630	3,730
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		15,860	19,608
Acquired Loans, Past Due		1,791	1,242
Nonaccrual	[1]	0	0
Total Acquired Loans		17,651	20,850
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	1,513	821
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		51,845	66,535
Acquired Loans, Past Due		2,876	2,964
Nonaccrual	[1]	0	41
Total Acquired Loans		54,721	69,540
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	683	1,057
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		88,320	101,453
Acquired Loans, Past Due		3,755	2,039
Nonaccrual	[1]	0	328
Total Acquired Loans		92,075	103,820
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	1,850	343
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		15,699	16,796
Acquired Loans, Past Due		576	2,214
Nonaccrual	[1]	0	0
Total Acquired Loans		16,275	19,010
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	576	1,445
Commercial and Industrial Loans [Member]
Acquired Loans, Aging [Abstract]
Current		20,668	36,535
Acquired Loans, Past Due		23	99
Nonaccrual	[1]	0	262
Total Acquired Loans		20,691	36,896
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	5	0
Consumer Loans [Member]
Acquired Loans, Aging [Abstract]
Current		2,603	3,250
Acquired Loans, Past Due		61	115
Nonaccrual	[1]	0	0
Total Acquired Loans		2,664	3,365
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	3	64
Other Loans [Member]
Acquired Loans, Aging [Abstract]
Current		14,165	18,766
Acquired Loans, Past Due		0	0
Nonaccrual	[1]	0	0
Total Acquired Loans		14,165	18,766
Other Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	0	0
Commercial LHFI [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		175,130	215,792
Commercial LHFI [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		130,838	160,293
Commercial LHFI [Member] | Special Mention [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		163	613
Commercial LHFI [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		41,262	51,904
Commercial LHFI [Member] | Doubtful [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		2,867	2,982
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		16,067	19,038
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		11,322	12,148
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Special Mention [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		93	99
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		4,130	6,469
Commercial LHFI [Member] | Construction, Land Development and Other Land [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		522	322
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		16,326	18,748
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		12,649	14,552
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Special Mention [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		52	61
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		3,573	4,066
Commercial LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		52	69
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		92,029	103,770
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		73,125	83,271
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Special Mention [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans			435
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		18,389	19,553
Commercial LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		515	511
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		15,855	18,582
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Pass [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		12,775	15,344
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Substandard [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		2,536	2,673
Commercial LHFI [Member] | Other Real Estate Secured [Member] | Doubtful [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		544	565
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		20,691	36,890
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		12,354	22,024
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Special Mention [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		18	18
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		7,202	13,494
Commercial LHFI [Member] | Commercial and Industrial Loans [Member] | Doubtful [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		1,117	1,354
Commercial LHFI [Member] | Other Loans [Member] | Commercial Loan [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		14,162	18,764
Commercial LHFI [Member] | Other Loans [Member] | Pass [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		8,613	12,954
Commercial LHFI [Member] | Other Loans [Member] | Substandard [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		5,432	5,649
Commercial LHFI [Member] | Other Loans [Member] | Doubtful [Member]
Acquired Loans, Commercial Loans [Abstract]
Acquired loans		117	161
Consumer LHFI [Member]
Acquired Loans, Aging [Abstract]
Current		41,050	54,232
Nonaccrual	[1]		24
Subtotal		43,112	56,455
Total Acquired Loans		218,242	272,247
Consumer LHFI [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,660	1,415
Consumer LHFI [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		402	784
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		1,469	1,801
Subtotal		1,584	1,812
Total Acquired Loans		17,651	20,850
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		102
Consumer LHFI [Member] | Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		13	11
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		36,509	48,695
Nonaccrual	[1]		24
Subtotal		38,395	50,792
Total Acquired Loans		54,721	69,540
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,500	1,364
Consumer LHFI [Member] | Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		386	709
Consumer LHFI [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		46	50
Subtotal		46	50
Total Acquired Loans		92,075	103,820
Consumer LHFI [Member] | Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Current		420	428
Subtotal		420	428
Total Acquired Loans		16,275	19,010
Consumer LHFI [Member] | Commercial and Industrial Loans [Member]
Acquired Loans, Aging [Abstract]
Current			6
Subtotal			6
Total Acquired Loans		20,691	36,896
Consumer LHFI [Member] | Consumer Loans [Member]
Acquired Loans, Aging [Abstract]
Current		2,603	3,250
Subtotal		2,664	3,365
Total Acquired Loans		2,664	3,365
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 30-89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		58	51
Consumer LHFI [Member] | Consumer Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		3	64
Consumer LHFI [Member] | Other Loans [Member]
Acquired Loans, Aging [Abstract]
Current		3	2
Subtotal		3	2
Total Acquired Loans		$ 14,165	$ 18,766
[1]	Acquired loans not accounted for under FASB ASC Topic 310-30.
[2]	Past due 90 days or more but still accruing interest.

Acquired Loans - Aging Analysis

Acquired Loans - Aging Analysis of Past Due and Nonaccrual Acquired Loans, by Class (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		$ 9,082	$ 8,673
Nonaccrual	[1]	0	631
Current		209,160	262,943
Acquired Loans		218,242	272,247
Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,912	4,354
Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		2,540	589
Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	4,630	3,730
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,791	1,242
Nonaccrual	[1]	0	0
Current		15,860	19,608
Acquired Loans		17,651	20,850
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		102	321
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		176	100
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	1,513	821
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		2,876	2,964
Nonaccrual	[1]	0	41
Current		51,845	66,535
Acquired Loans		54,721	69,540
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,568	1,495
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		625	412
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	683	1,057
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		3,755	2,039
Nonaccrual	[1]	0	328
Current		88,320	101,453
Acquired Loans		92,075	103,820
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		166	1,658
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		1,739	38
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	1,850	343
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		576	2,214
Nonaccrual	[1]	0	0
Current		15,699	16,796
Acquired Loans		16,275	19,010
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	769
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	0
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	576	1,445
Commercial and Industrial Loans [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		23	99
Nonaccrual	[1]	0	262
Current		20,668	36,535
Acquired Loans		20,691	36,896
Commercial and Industrial Loans [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		18	60
Commercial and Industrial Loans [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	39
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	5	0
Consumer Loans [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		61	115
Nonaccrual	[1]	0	0
Current		2,603	3,250
Acquired Loans		2,664	3,365
Consumer Loans [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		58	51
Consumer Loans [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	0
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	3	64
Other Loans [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	0
Nonaccrual	[1]	0	0
Current		14,165	18,766
Acquired Loans		14,165	18,766
Other Loans [Member] | Past Due 30 to 59 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	0
Other Loans [Member] | Past Due 60 to 89 Days [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due		0	0
Other Loans [Member] | Past Due 90 Days or More [Member]
Acquired Loans, Aging [Abstract]
Acquired Loans, Past Due	[2]	$ 0	$ 0
[1]	Acquired loans not accounted for under FASB ASC Topic 310-30.
[2]	Past due 90 days or more but still accruing interest.

Mortgage Banking - Schedule of

Mortgage Banking - Schedule of Activity in the Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Mortgage servicing rights [Abstract]
Balance at beginning of period	$ 80,239	$ 74,007
Origination of servicing assets	3,440	3,072
Change in fair value [Abstract]
Due to market changes	1,466	(6,866)
Due to run-off	(2,387)	(2,005)
Balance at end of period	$ 82,758	$ 68,208

Mortgage Banking - Additional I

Mortgage Banking - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Mortgage servicing rights [Abstract]
Residential mortgage loans sold	$ 260,100	$ 235,400
Gains on sales of residential mortgage loans, before tax	$ 3,600	2,600
Period of putback response	60 days
Mortgage loan servicing putback expenses	$ 105	$ 105

Mortgage Banking - Schedule o74

Mortgage Banking - Schedule of Mortgage Loans Sold and Serviced for Others (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	$ 6,424,502	$ 6,371,342
Federal National Mortgage Association [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	4,033,540	3,992,349
Government National Mortgage Association [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	2,307,321	2,291,398
Federal Home Loan Mortgage Corporation [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	53,377	55,006
Other [Member]
Mortgage Loans On Real Estate [Line Items]
Total mortgage loans sold and serviced for others	$ 30,264	$ 32,589

Mortgage Banking - Changes in t

Mortgage Banking - Changes in the Reserve for Mortgage Loan Servicing Putback Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Schedule of changes in the reserve for mortgage loan [Abstract]
Balance at beginning of period	$ 1,130	$ 1,685
Provision for putback expenses	105	105
Gains (losses)	16	(5)
Balance at end of period	$ 1,251	$ 1,785

Other Real Estate - Changes and

Other Real Estate - Changes and Gains, Net on Other Real Estate (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	[1]
Reconciliation Of Carrying Amount Of Real Estate Investments Roll Forward
Balance at beginning of period	$ 62,051	$ 78,828
Additions	1,766	3,608
Disposals	(6,385)	(8,994)
Write-downs	(1,464)	(1,140)
Balance at end of period	55,968	72,302
Gain, net on the sale of other real estate included in other real estate expense	$ 470	$ 1,868
[1]	The changes and gains, net on other real estate for the three months ended March 31, 2016 include covered other real estate.

Other Real Estate - Other Real

Other Real Estate - Other Real Estate, By Type of Property (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	[1]	Dec. 31, 2015	[1]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	$ 55,968	$ 62,051	$ 72,302		$ 78,828
Construction, Land Development And Other Land Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	35,256	36,871
1 - 4 Family Residential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	6,818	7,926
Nonfarm, Nonresidential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	13,457	16,817
Other Real Estate Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	$ 437	$ 437
[1]	The changes and gains, net on other real estate for the three months ended March 31, 2016 include covered other real estate.

Other Real Estate - Other Rea78

Other Real Estate - Other Real Estate, By Geographic Location (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	[1]	Dec. 31, 2015	[1]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 55,968	$ 62,051	$ 72,302		$ 78,828
Alabama [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		13,953	15,989
Florida [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		21,577	22,582
Mississippi [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[2]	14,974	15,646
Tennessee [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[3]	4,706	6,183
Texas [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 758	$ 1,651
[1]	The changes and gains, net on other real estate for the three months ended March 31, 2016 include covered other real estate.
[2]	Mississippi includes Central and Southern Mississippi Regions
[3]	Tennessee includes Memphis, Tennessee and Northern Mississippi Regions

Deposits - Deposits Summary (De

Deposits - Deposits Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Deposits [Abstract]
Noninterest-bearing demand	$ 3,209,727	$ 2,973,238
Interest-bearing demand	1,927,415	1,875,312
Savings	3,295,565	3,586,369
Time	1,671,765	1,621,093
Total deposits	$ 10,104,472	$ 10,056,012

Securities Sold Under Repurch80

Securities Sold Under Repurchase Agreement - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Securities sold under repurchase agreements, secured by securities carrying amount	$ 277.8	$ 284.4

Securities Sold Under Repurch81

Securities Sold Under Repurchase Agreements (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Securities sold under repurchase agreements by collateral pledged
Total securities sold under repurchase agreements	$ 139,216	$ 127,007
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	87,525	75,795
Commercial 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	$ 51,691	$ 51,212

Defined Benefit and Other Pos82

Defined Benefit and Other Postretirement Benefits - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2017
Trustmark Capital Accumulation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Years of service required to vest	3 years
Spin-Off Plan [Member] | Scenario 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		$ 0

Defined Benefit and Other Pos83

Defined Benefit and Other Postretirement Benefits - Net Periodic Benefit Cost for Plan and Spin-Off plan (Details) - Trustmark Capital Accumulation Plan [Member] - Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net periodic benefit cost [Abstract]
Service cost	$ 63	$ 108
Interest cost	665	830
Expected return on plan assets	(108)	(1,022)
Recognized net loss due to lump sum settlements	0	423
Recognized net actuarial loss	565	661
Net periodic benefit cost	$ 1,185	$ 1,000

Defined Benefit and Other Pos84

Defined Benefit and Other Postretirement Benefits - Net Periodic Benefit Cost (Details) - Supplemental Retirement Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net periodic benefit cost [Abstract]
Service cost	$ 35	$ 74
Interest cost	561	546
Amortization of prior service cost	63	63
Recognized net actuarial loss	222	221
Net periodic benefit cost	$ 881	$ 904

Stock and Incentive Compensat85

Stock and Incentive Compensation Plans (Details)	3 Months Ended
	Mar. 31, 2017
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Return on average tangible equity, performance measure	100.00%
Performance Based Award [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Time-Vested Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years

Stock and Incentive Compensat86

Stock and Incentive Compensation Plans - Summary of Stock Plan Activity (Details) - Stock and Incentive Compensation Plan [Member]	3 Months Ended
	Mar. 31, 2017shares
Performance Based Award [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	237,136
Granted (in shares)	58,406
Released from restriction (in shares)	(62,601)
Forfeited (in shares)	(2,947)
Nonvested shares, end of period (in shares)	229,994
Time-Vested Awards [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	322,056
Granted (in shares)	88,224
Released from restriction (in shares)	(83,862)
Forfeited (in shares)	(734)
Nonvested shares, end of period (in shares)	325,684

Stock and Incentive Compensat87

Stock and Incentive Compensation Plans - Compensation Expense for Awards Under Stock Plan (Details) - Stock and Incentive Compensation Plan [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total compensation expense	$ 953	$ 961
Performance Based Award [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total compensation expense	105	100
Time-Vested Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total compensation expense	$ 848	$ 861

Contingencies - Additional Info

Contingencies - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)Lawsuit	Mar. 31, 2016USD ($)
Loss Contingencies [Line Items]
Unused commitments to extend credit	$ 3,052	$ 3,007
Pending or Threatened Litigation, Stanford Financial Group [Member]
Legal Proceedings [Abstract]
Lawsuits naming entity as defendant, number | Lawsuit	3
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Letters of credit, maturity term - maximum	3 years
Collateral held, fair value	$ 33.7	30
Standby Letters of Credit [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Potential exposure to credit loss in the event of nonperformance	$ 109.2	$ 114.9

Earnings Per Share (EPS) - Weig

Earnings Per Share (EPS) - Weighted-Average Shares Used to Calculate Basic and Diluted EPS (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Basic shares (in shares)	67,687	67,610
Dilutive shares (in shares)	159	137
Diluted shares (in shares)	67,846	67,747

Earnings Per Share (EPS) - We90

Earnings Per Share (EPS) - Weighted-Average Antidilutive Stock Awards Excluded from Determining Diluted EPS (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Weighted-average antidilutive stock awards	43	0

Statements of Cash Flows (Detai

Statements of Cash Flows (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Statement of cash flows specific transaction amounts [Abstract]
Income taxes paid		$ 778	$ 376
Interest expense paid on deposits and borrowings		7,190	4,986
Noncash transfers from loans to other real estate	[1]	$ 1,766	$ 3,608
[1]	Includes transfers from covered loans to covered other real estate.

Statements of Cash Flows - Addi

Statements of Cash Flows - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Excess tax expense from stock-based compensation arrangements being reclassified from financing activities to other operating activities, net		$ 147
Taxes paid for shares directly withheld being reclassified from other operating activities, net to financing activities	$ 1,543	$ 799

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Mar. 11, 2016
Stockholders Equity [Line items]
Capital conservation buffer rate	1.25%		0.625%
Stock Repurchase Program
Stockholders Equity [Line items]
Amount of stock authorized for repurchase				$ 100
Repurchase shares of common stock	0	0

Shareholders' Equity - Table of

Shareholders' Equity - Table of Actual Regulatory Capital Amounts and Ratios (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
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		$ 1,223,078	$ 1,209,927
Actual Regulatory Capital Ratio		12.19%	12.16%
Minimum Regulatory Capital Required Ratio		5.75%	5.125%
Minimum Regulatory Provision to be Well-Capitalized Ratio	[1]
Trustmark Corporation [Member] | Tier 1 Capital (to Risk Weighted Assets) [Member]
Tier 1 Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount		$ 1,282,919	$ 1,269,660
Actual Regulatory Capital Ratio		12.79%	12.76%
Minimum Regulatory Capital Required Ratio		7.25%	6.625%
Minimum Regulatory Provision to be Well-Capitalized Ratio	[1]
Trustmark Corporation [Member] | Total Capital (to Risk Weighted Assets) [Member]
Total Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount		$ 1,365,370	$ 1,352,322
Actual Regulatory Capital Ratio		13.61%	13.59%
Minimum Regulatory Capital Required Ratio		9.25%	8.625%
Minimum Regulatory Provision to be Well-Capitalized Ratio	[1]
Trustmark Corporation [Member] | Tier 1 Leverage (to Average Assets) [Member]
Tier 1 Leverage (to Average Assets) [Abstract]
Actual Regulatory Capital Amount		$ 1,282,919	$ 1,269,660
Actual Regulatory Capital Ratio		9.86%	9.90%
Minimum Regulatory Capital Required Ratio		4.00%	4.00%
Minimum Regulatory Provision to be Well-Capitalized Ratio	[1]
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		$ 1,266,309	$ 1,251,329
Actual Regulatory Capital Ratio		12.63%	12.58%
Minimum Regulatory Capital Required Ratio		5.75%	5.125%
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		$ 1,266,309	$ 1,251,329
Actual Regulatory Capital Ratio		12.63%	12.58%
Minimum Regulatory Capital Required Ratio		7.25%	6.625%
Minimum Regulatory Provision to be Well-Capitalized Ratio		8.00%	8.00%
Trustmark National Bank [Member] | Total Capital (to Risk Weighted Assets) [Member]
Total Capital (to Risk Weighted Assets) [Abstract]
Actual Regulatory Capital Amount		$ 1,348,760	$ 1,333,991
Actual Regulatory Capital Ratio		13.45%	13.41%
Minimum Regulatory Capital Required Ratio		9.25%	8.625%
Minimum Regulatory Provision to be Well-Capitalized Ratio		10.00%	10.00%
Trustmark National Bank [Member] | Tier 1 Leverage (to Average Assets) [Member]
Tier 1 Leverage (to Average Assets) [Abstract]
Actual Regulatory Capital Amount		$ 1,266,309	$ 1,251,329
Actual Regulatory Capital Ratio		9.75%	9.77%
Minimum Regulatory Capital Required Ratio		4.00%	4.00%
Minimum Regulatory Provision to be Well-Capitalized Ratio		5.00%	5.00%
[1]	n/a

Shareholders' Equity - Componen

Shareholders' Equity - Components of Accumulated Other Comprehensive Income (Loss) and the Related Tax Effects (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Securities available for sale and transferred securities, Before tax amount [Abstract]
Unrealized holding (losses) gains arising during the period, Before tax amount	$ 2,285	$ 35,343
Reclassification adjustment for net losses (gains) realized in net income, Before tax amount	0	310
Change in net unrealized holding loss on securities transferred to held to maturity, Before tax amount	1,232	2,724
Total securities available for sale and transferred securities, Before tax amount	3,517	38,377
Securities available for sale and transferred securities, Tax (expense) benefit [Abstract]
Unrealized holding (losses) gains arising during the period, Tax (expense) benefit	(874)	(13,518)
Reclassification adjustment for net gains realized in net income, Tax (expense) benefit	0	(119)
Change in net unrealized holding loss on securities transferred to held to maturity, Tax (expense) benefit	(471)	(1,042)
Total securities available for sale and transferred securities, Tax (expense) benefit	(1,345)	(14,679)
Securities available for sale and transferred securities, Net of tax amount [Abstract]
Unrealized holding (losses) gains arising during the period, net of tax amount	1,411	21,825
Reclassification adjustment for net losses (gains) realized in net income, net of tax amount	0	191
Change in net unrealized holding loss on securities transferred to held to maturity	761	1,682
Total securities available for sale and transferred securities, net of tax amount	2,172	23,698
Pension and other postretirement benefit plans, Before tax amount [Abstract]
Net change in prior service costs, before tax amount	63	62
Recognized net loss due to lump sum settlements, before tax amount	0	423
Change in net actuarial loss, before tax amount	787	882
Total pension and other postretirement benefit plans, before tax amount	850	1,367
Pension and other postretirement benefit plans, Tax (expense) benefit [Abstract]
Net change in prior service costs, tax (expense) benefit	(24)	(24)
Recognized net loss due to lump sum settlements, tax (expense) benefit	0	(162)
Change in net actuarial loss, tax (expense) benefit	(301)	(337)
Total pension and other postretirement benefit plans, tax (expense) benefit	325	523
Pension and other postretirement benefit plans, Net of tax amount [Abstract]
Net change in prior service costs, net of tax amount	39	38
Recognized net loss due to lump sum settlements, net of tax amount	0	261
Change in net actuarial loss, net of tax amount	486	545
Total pension and other postretirement benefit plans, net of tax amount	525	844
Cash flow hedge derivatives, Before tax amount [Abstract]
Change in accumulated gain (loss) on effective cash flow hedge derivatives, before tax amount	57	(1,328)
Reclassification adjustment for loss realized in net income, before tax amount	99	160
Total cash flow hedge derivatives, before tax benefit	156	(1,168)
Total other comprehensive income (loss), Before tax amount	4,523	38,576
Cash flow hedge derivatives, Tax (expense) benefit [Abstract]
Change in accumulated gain (loss) on effective cash flow hedge derivatives , tax (expense) benefit	(22)	508
Reclassification adjustment for loss realized in net income, tax (expense) benefit	(38)	(61)
Total cash flow hedge derivatives, tax (expense) benefit	60	(447)
Total other comprehensive income (loss), Tax expense (benefit)	(1,730)	(14,755)
Cash flow hedge derivatives, Net of tax amount [Abstract]
Change in accumulated gain (loss) on effective cash flow hedge derivatives, net of tax amount	35	(820)
Reclassification adjustment for loss realized in net income, net of tax amount	61	99
Total cash flow hedge derivatives, net of tax amount	96	(721)
Total other comprehensive income (loss), net of tax amount	$ 2,793	$ 23,821

Shareholders' Equity - Changes

Shareholders' Equity - Changes in Balances of Component of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 1,520,208	$ 1,473,057
Other comprehensive income (loss) before reclassification	2,207	22,687
Amounts reclassified from accumulated other comprehensive loss	586	1,134
Total other comprehensive income (loss), net of tax amount	2,793	23,821
Balance	1,537,961	1,508,256
Securities Available for Sale and Transferred Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(20,800)	(17,394)
Other comprehensive income (loss) before reclassification	2,172	23,507
Amounts reclassified from accumulated other comprehensive loss		191
Total other comprehensive income (loss), net of tax amount	2,172	23,698
Balance	(18,628)	6,304
Defined Benefit Pension Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(24,980)	(27,840)
Amounts reclassified from accumulated other comprehensive loss	525	844
Total other comprehensive income (loss), net of tax amount	525	844
Balance	(24,455)	(26,996)
Cash Flow Hedge Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(18)	(160)
Other comprehensive income (loss) before reclassification	35	(820)
Amounts reclassified from accumulated other comprehensive loss	61	99
Total other comprehensive income (loss), net of tax amount	96	(721)
Balance	78	(881)
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(45,798)	(45,394)
Balance	$ (43,005)	$ (21,573)

Fair Value - Financial Assets a

Fair Value - Financial Assets and Liabilities Measured at Fair Value Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 2,365,554	$ 2,356,682
Loans held for sale	174,090	175,927
Mortgage servicing rights	82,758	80,239	$ 68,208	$ 74,007
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	109,895	115,373
Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,365,554	2,356,682
Loans held for sale	174,090	175,927
Mortgage servicing rights	82,758	80,239
Other assets - derivatives	4,230	2,518
Other liabilities - derivatives	3,676	412
Recurring Basis [Member] | US Treasury and Government [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	53,521	56,039
Recurring Basis [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	109,895	115,373
Recurring Basis [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,202,138	2,185,270
Level 1 [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	0	0
Mortgage servicing rights	0	0
Other assets - derivatives	521	(524)
Other liabilities - derivatives	909	1,174
Level 1 [Member] | Recurring Basis [Member] | US Treasury and Government [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] | Obligations of States and Political Subdivisions [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	2,365,554	2,356,682
Loans held for sale	174,090	175,927
Mortgage servicing rights	0	0
Other assets - derivatives	1,564	2,041
Other liabilities - derivatives	2,767	(762)
Level 2 [Member] | Recurring Basis [Member] | US Treasury and Government [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	53,521	56,039
Level 2 [Member] | Recurring Basis [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	109,895	115,373
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	2,202,138	2,185,270
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	0	0
Mortgage servicing rights	82,758	80,239
Other assets - derivatives	2,145	1,001
Other liabilities - derivatives	0	0
Level 3 [Member] | Recurring Basis [Member] | US Treasury and Government [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] | Obligations of States and Political Subdivisions [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) - Recurring Basis [Member] - Level 3 [Member] - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
MSR [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		$ 80,239	$ 74,007
Total net (loss) gain included in Mortgage banking, net	[1]	(921)	(8,871)
Additions		3,440	3,072
Sales		0	0
Ending Balance		82,758	68,208
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		1,466	(6,866)
Other Assets - Derivatives [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		1,001	1,113
Total net (loss) gain included in Mortgage banking, net	[1]	1,955	3,097
Additions		0	0
Sales		(811)	(926)
Ending Balance		2,145	3,284
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		$ 342	$ 398
[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) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)Region	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Nonfinancial Assets and Liabilities [Abstract]
Outstanding balances in impaired loans	$ 39,100		$ 27,100
Key market regions | Region	5
Foreclosed assets re-measured after initial recognition	$ 10,300	$ 12,200
Write-downs of allowance for foreclosed assets after initial recognition	1,500	1,100
Noninterest gain in Mortgage banking, net for changes in fair value of LHFS	3,600	2,800
Interest earned on LHFS included in Interest and fees on LHFS and LHFI	1,100	$ 867
GNMA optional repurchase loans	$ 38,900		$ 43,900
Maximum [Member]
Nonfinancial Assets and Liabilities [Abstract]
Estimated fair value of financial instruments with immediate and shorter-term maturities	90 days

Fair Value - Carrying Amounts a

Fair Value - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	$ 1,156,067	$ 1,158,643
Net LHFI	7,932,212	7,779,948
Acquired loans	208,236	260,850
Deposits	10,104,472	10,056,012
Long-term FHLB advances	250,994	251,049
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	380,090	328,206
Securities held to maturity	1,156,067	1,158,643
Deposits	10,104,472	10,056,012
Short-term liabilities	1,389,025	1,309,595
Long-term FHLB advances	250,994	251,049
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	380,090	328,206
Securities held to maturity	1,154,415	1,157,046
Deposits	10,105,262	10,059,794
Short-term liabilities	1,389,025	1,309,595
Long-term FHLB advances	250,994	251,050
Junior subordinated debt securities	43,299	41,057
Level 3 [Member] | Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	7,932,212	7,779,948
Acquired loans	208,236	260,850
Level 3 [Member] | Estimate Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net LHFI	8,001,968	7,825,009
Acquired loans	$ 208,236	$ 260,850

Fair Value - Fair Value and the

Fair Value - Fair Value and the Contractual Principal Outstanding of the LHFS (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair value and the contractual principal outstanding of the LHFS [Abstract]
Fair value of LHFS	$ 135,170	$ 132,002
LHFS contractual principal outstanding	131,632	132,047
Fair value less unpaid principal	$ 3,538	$ (45)

Derivative Financial Instrum102

Derivative Financial Instruments - Additional Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2017USD ($)Contract	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)Contract	Apr. 04, 2013USD ($)
Designated as Hedging Instrument [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Accumulated net, after tax (loss) gain included in other comprehensive loss	$ 35,000	$ (820,000)
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Period for which cash flow hedges will be used to hedge quarterly interest payments	5 years
Derivative inception date	Dec. 31, 2014
Derivative maturity date	Dec. 31, 2019
Description of variable rate basis for derivative	three-month LIBOR
Ineffectiveness related to interest rate swap designated as a cash flow hedge	$ 0	0
Accumulated net, after tax (loss) gain included in other comprehensive loss	$ 78,000		$ (17,000)
The period over which OCI will be reclassified as interest expense	12 months
Estimated amount to be reclassified as an increase to interest expense	$ 178,000
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Junior Subordinated Debentures [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount				$ 60,000,000
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Three-month LIBOR [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Swap fixed interest rate to be paid	1.66%
Derivatives not Designated as Hedging Instruments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	$ 285,500,000		$ 262,000,000
Net positive ineffectiveness on MSR fair value	$ 2,800,000	$ 413,000
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	2		2
Aggregate notional amount of credit risk participation agreements	$ 14,100,000		$ 14,200,000
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	5		5
Aggregate notional amount of credit risk participation agreements	$ 27,900,000		$ 28,000,000
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total notional amount	336,700,000		340,200,000
Termination value of derivatives	711,000		1,200,000
Collateral Posted	100,000
Derivatives not Designated as Hedging Instruments [Member] | Forward Contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet obligations	231,000,000		195,000,000
Valuation adjustment	(1,200,000)		2,800,000
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	143,500,000		97,900,000
Valuation adjustment	$ 2,100,000		$ 1,000,000

Derivative Financial Instrum103

Derivative Financial Instruments - Fair Value of Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	$ 1,558	$ 2,032
Fair value of derivative liability	1,584	2,065
Derivatives in Hedging Relationships [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	127	(28)
Derivatives not Designated as Hedging Instruments [Member] | Future Contracts [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	299	(626)
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	6	9
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	8	11
Derivatives not Designated as Hedging Instruments [Member] | Forward Contracts [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	1,175	(2,838)
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	1,431	2,060
Derivatives not Designated as Hedging Instruments [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	1,584	2,065
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	222	102
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	2,145	1,001
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	$ 909	$ 1,174

Derivative Financial Instrum104

Derivative Financial Instruments - Effects of Derivative Instruments on Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivatives in Hedging Relationships [Member] | Accumulated Other Comprehensive Loss and Other Interest Expense [Member]
Derivatives, Fair Value [Line Items]
Amount of loss reclassified from accumulated other comprehensive loss and recognized in other interest expense	$ (99)	$ (160)
Derivatives not Designated as Hedging Instruments [Member] | Mortgage Banking, Net [Member]
Derivatives, Fair Value [Line Items]
Amount of (loss) gain recognized in mortgage banking, net	(1,544)	7,139
Derivatives not Designated as Hedging Instruments [Member] | Bank Card and Other Fees [Member]
Derivatives, Fair Value [Line Items]
Amount of loss recognized in bank card and other fees	$ (28)	$ (58)

Derivative Financial Instrum105

Derivative Financial Instruments - Schedule of Amount Included in Other Comprehensive Income for Derivative Instruments Designated as Hedges of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivatives in Hedging Relationships [Member]
Derivatives in cash flow hedging relationship
Amount of gain (loss) recognized in other comprehensive income, net of tax	$ 35	$ (820)

Derivative Financial Instrum106

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, 2017	Dec. 31, 2016
Offsetting Derivative Assets
Gross Amounts of Recognized Assets, Offsetting of Derivative Assets	$ 1,558	$ 2,032
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	1,558	2,032
Financial Instruments, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Assets	(182)	(499)
Cash Collateral Received, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Assets	0	0
Net Amount, Offsetting of Derivative Assets	1,376	1,533
Offsetting Derivative Liabilities
Gross Amounts of Recognized Liabilities, Offsetting of Derivative Liabilities	1,584	2,065
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	1,584	2,065
Financial Instruments, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Liabilities	(182)	(499)
Cash Collateral Posted, Gross Amounts Not Offset in the Statement of Financial Position, Offsetting of Derivative Liabilities	(100)	(937)
Net Amount, Offsetting of Derivative Liabilities	$ 1,302	$ 629

Segment Information - Additiona

Segment Information - Additional Information (Details)	3 Months Ended
	Mar. 31, 2017Segment
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, 2017	Mar. 31, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net interest income	$ 97,590	$ 94,740
Provision for loan losses, net	1,157	3,552
Noninterest income	46,033	43,276
Noninterest expense	102,057	98,944
Income Before Income Taxes	40,409	35,520
Income taxes	9,161	8,517
Net Income	31,248	27,003
Selected Financial Information
Total assets	13,490,361	12,775,196	$ 13,352,333
Depreciation and amortization	9,031	8,721
General Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	97,411	94,442
Provision for loan losses, net	1,157	3,552
Noninterest income	29,440	27,394
Noninterest expense	87,357	85,893
Income Before Income Taxes	38,337	32,391
Income taxes	8,369	7,319
Net Income	29,968	25,072
Selected Financial Information
Total assets	13,417,229	12,701,364
Depreciation and amortization	8,836	8,485
Wealth Management [Member]
Segment Reporting Information [Line Items]
Net interest income	129	245
Noninterest income	7,377	7,288
Noninterest expense	7,201	5,891
Income Before Income Taxes	305	1,642
Income taxes	116	628
Net Income	189	1,014
Selected Financial Information
Total assets	7,279	7,329
Depreciation and amortization	37	44
Insurance [Member]
Segment Reporting Information [Line Items]
Net interest income	50	53
Noninterest income	9,216	8,594
Noninterest expense	7,499	7,160
Income Before Income Taxes	1,767	1,487
Income taxes	676	570
Net Income	1,091	917
Selected Financial Information
Total assets	65,853	66,503
Depreciation and amortization	$ 158	$ 192