Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net income per consolidated statements of income		$ 147,365	$ 160,025	$ 150,460
Adjustments to reconcile net income to net cash provided by operating activities:
Credit loss expense, net	[1]	(24,448)	45,047	10,839
Depreciation and amortization		45,813	41,325	39,420
Net amortization of securities		20,310	13,247	7,789
Gains on sales of loans, net		(70,954)	(94,986)	(27,301)
Compensation expense, long-term incentive plan		5,601	5,197	4,787
Deferred income tax provision		20,115	(19,800)	(3,880)
Proceeds from sales of LHFS		2,357,108	2,627,122	1,431,003
Purchases and originations of LHFS		(2,171,605)	(2,668,642)	(1,480,752)
Originations of MSR		(28,125)	(29,805)	(16,711)
Earnings on bank-owned life insurance		(4,853)	(5,099)	(5,592)
Net change in other assets		42,400	(49,653)	(30,729)
Net change in other liabilities		19,645	13,669	13,276
Other operating activities, net		(9,601)	27,699	23,838
Net cash from operating activities		348,771	65,346	116,447
Investing Activities
Proceeds from maturities, prepayments and calls of securities held to maturity		197,091	201,888	173,385
Proceeds from maturities, prepayments and calls of securities available for sale		835,200	680,294	425,260
Purchases of securities available for sale		(2,150,935)	(1,051,014)	(177,739)
Net proceeds from bank-owned life insurance		1,772	3,280	4,140
Net change in federal funds sold and securities purchased under reverse repurchase agreements		50	(50)	830
Net change in member bank stock		(1,220)	269	262
Net change in loans		(197,800)	(1,027,924)	(480,295)
Proceeds from sales of PPP loans		353,287
Purchases of premises and equipment		(27,360)	(22,577)	(17,327)
Proceeds from sales of premises and equipment		961	2,803	3,248
Proceeds from sales of other real estate		5,064	17,343	11,182
Purchases of software		(3,836)	(8,252)	(13,412)
Investments in tax credit and other partnerships		(17,288)	(5,844)	(3,426)
Purchase of insurance book of business			(3,097)	(347)
Net cash used in business acquisition			(4,834)
Net cash from investing activities		(1,005,014)	(1,217,715)	(74,239)
Financing Activities
Net change in deposits		1,038,396	2,803,207	(118,854)
Net change in federal funds purchased and securities sold under repurchase agreements		74,058	(91,501)	205,549
Net change in other borrowings		(19,189)	473	493
Payments under finance lease obligations		(1,434)	(1,715)	(1,964)
Proceeds from subordinated notes			122,900
Common stock dividends		(58,085)	(58,769)	(59,804)
Repurchase and retirement of common stock		(61,799)	(27,538)	(56,615)
Shares withheld to pay taxes, long-term incentive plan		(1,379)	(1,100)	(1,658)
Net cash from financing activities		970,568	2,745,957	(32,853)
Net change in cash and cash equivalents		314,325	1,593,588	9,355
Cash and cash equivalents at beginning of year		1,952,504	358,916	349,561
Cash and cash equivalents at end of year		$ 2,266,829	$ 1,952,504	$ 358,916

[1] Effective January 1, 2020, Trustmark adopted FASB ASU 2016-13 using the modified retrospective approach. Therefore, prior period balances are presented under legacy GAAP and may not be comparable to current period presentation.