Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 69,150	$ 65,213	$ 204,480	$ 202,550
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	46	(327)	(352)	(306)
Net unrealized gains (losses) on other securities	(13,747)	16,891	87,887	2,754
Pension loss amortization	359	283	1,077	1,095
Other comprehensive income (loss), net of tax	(13,342)	16,847	88,612	3,543
Comprehensive income	55,808	82,060	293,092	206,093
Non-controlling interest expense (income)	605	601	668	2,530
Comprehensive income attributable to Commerce Bancshares, Inc	$ 55,203	$ 81,459	$ 292,424	$ 203,563