Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 75,323	$ 65,900	$ 137,337	$ 130,021
Other comprehensive income (loss)
Net unrealized gains (losses) on securities for which a portion of an other-than-temporary impairment has been recorded in earnings	149	(58)	21	108
Net unrealized gains (losses) on other securities	(43,483)	43,650	(14,137)	74,029
Pension loss amortization	406	223	812	446
Other comprehensive income (loss), net of tax	(42,928)	43,815	(13,304)	74,583
Comprehensive income	32,395	109,715	124,033	204,604
Non-controlling interest expense	970	(631)	1,929	(823)
Comprehensive income attributable to Commerce Bancshares, Inc	$ 31,425	$ 110,346	$ 122,104	$ 205,427