Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 65,213	$ 69,021	$ 202,550	$ 199,042
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	(327)	(244)	(306)	(136)
Net unrealized gains (losses) on other securities	16,891	(24,062)	2,754	49,967
Pension loss amortization	283	223	1,095	669
Other comprehensive income (loss), net of tax	16,847	(24,083)	3,543	50,500
Comprehensive income	82,060	44,938	206,093	249,542
Non-controlling interest expense	601	836	2,530	13
Comprehensive income attributable to Commerce Bancshares, Inc	$ 81,459	$ 44,102	$ 203,563	$ 249,529