Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Numerator: [Abstract]:
Net income attributable to BOK Financial Corp. shareholders	$ 316,609	$ 351,191	$ 285,875
Less: Earnings allocated to participating securities	3,388	2,541	2,214
Numerator for basic earnings per share - income available to common shareholders	313,221	348,650	283,661
Effect of reallocating undistributed earnings of participating securities	7	6	6
Numerator for diluted earnings per share - income available to common shareholders	$ 313,228	$ 348,656	$ 283,667
Denominator: [Abstract]
Weighted average shares outstanding	68,719,069	68,221,013	68,313,898
Less: Participating securities included in weighted average shares outstanding (in shares)	730,172	536,970	526,222
Denominator for basic earnings per common share (in shares)	67,988,897	67,684,043	67,787,676
Dilutive effect of employee stock compensation plans (in shares)	216,622	280,897	251,087
Denominator for diluted earnings per common share (in shares)	68,205,519	67,964,940	68,038,763
Basic earnings per share (per share)	$ 4.61	$ 5.15	$ 4.18
Diluted earnings per share (per share)	$ 4.59	$ 5.13	$ 4.17
Excludes employee stock options with exercise prices greater than current market price.	0	224,653	769,041