Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator: [Abstract]:
Net income attributable to BOK Financial Corp. shareholders	$ 618,121	$ 435,030	$ 500,758
Less: Earnings allocated to participating securities	4,299	2,612	3,227
Numerator for basic earnings per share - income available to common shareholders	613,822	432,418	497,531
Effect of reallocating undistributed earnings of participating securities	0	0	0
Numerator for diluted earnings per share - income available to common shareholders	$ 613,822	$ 432,418	$ 497,531
Denominator: [Abstract]
Weighted average shares outstanding	69,071,511	70,259,553	71,250,081
Less: Participating securities included in weighted average shares outstanding (in shares)	479,591	418,576	462,381
Denominator for basic earnings per common share (in shares)	68,591,920	69,840,977	70,787,700
Dilutive effect of employee stock compensation plans (in shares)	2,402	3,195	14,912
Denominator for diluted earnings per common share (in shares)	68,594,322	69,844,172	70,802,612
Basic (in dollars per share)	$ 8.95	$ 6.19	$ 7.03
Diluted earnings per share (per share)	$ 8.95	$ 6.19	$ 7.03