Consolidated Statements Of Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
INTEREST INCOME
Interest and fees on loans		$ 570,549	$ 612,072	$ 663,338
Interest on loans held for sale		880	860	1,209
Interest on investment securities		236,278	216,793	237,487
Interest on federal funds sold and short-term securities purchased under agreements to resell		4	3	55
Interest on Long-Term Securities Purchased Under Agreements To Resell		37,377	40,647	15,898
Interest on deposits with banks		3,202	2,273	6,698
Total interest income		848,290	872,648	924,685
INTEREST EXPENSE
Savings, interest checking and money market		7,509	17,851	39,712
Certificates of deposit of less than $100,000		1,158	4,897	6,368
Certificates of deposit of $100,000 and over		2,577	12,948	26,945
Interest on federal funds purchased and securities sold under agreements to repurchase		1,646	6,091	29,415
Interest on other borrowings		(24)	1,014	952
Total interest expense		12,866	42,801	103,392
Net interest income		835,424	829,847	821,293
Provision for loan losses		(66,326)	137,190	50,438
Net interest income after provision for loan losses		901,750	692,657	770,855
NON-INTEREST INCOME
Bank card transaction fees		167,891	151,797	167,879
Trust fees		188,227	160,637	155,628
Deposit account charges and other fees		97,217	93,227	95,983
Capital market fees		15,943	14,582	8,146
Consumer brokerage		18,362	15,095	15,804
Loan fees and sales		29,720	26,684	15,767
Other		43,033	43,845	65,496
Total non-interest income		560,393	505,867	524,703
INVESTMENT SECURITIES GAINS (LOSSES), NET
Investment securities gains (losses), net	[1]	30,059	11,032	3,626
NON-INTEREST EXPENSE
Salaries and employee benefits		525,248	512,987	492,927
Net occupancy		48,185	46,645	47,157
Equipment		18,089	18,839	19,061
Supplies and communication		17,118	17,419	20,394
Data processing and software		101,792	95,325	92,899
Marketing		21,856	19,734	21,914
Other		73,613	57,429	73,046
Total non-interest expense		805,901	768,378	767,398
Income before income taxes		686,301	441,178	531,786
Less income taxes		145,711	87,293	109,074
Net income		540,590	353,885	422,712
Less non-controlling interest expense (income)		9,825	(172)	1,481
NET INCOME ATTRIBUTABLE TO COMMERCE BANCSHARES, INC.		530,765	354,057	421,231
Preferred stock dividends		0	11,966	9,000
Net Income (Loss) Available to Common Stockholders, Basic		$ 530,765	$ 342,091	$ 412,231
Net income per common share - basic (in dollars per share)		$ 4.32	$ 2.77	$ 3.25
Net income per common share - diluted (in dollars per share)		$ 4.31	$ 2.77	$ 3.25

[1] Available for sale debt securities, equity securities, and other securities.