Federal and State Income Taxes (Tables)

6 Months Ended

Jun. 30, 2014

Income Tax Disclosure [Abstract]

Reconciliation of income (loss) to income tax expense

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2014			2013			2014			2013
Amount:
Federal statutory tax	$	39,886		$	42,459		$	79,976		$	90,113
Tax exempt revenue	(2,099		)	(1,803		)	(4,090		)	(3,545		)
Effect of state income taxes, net of federal benefit	2,457			3,122			5,327			6,500
Utilization of tax credits	(2,836		)	(1,826		)	(5,466		)	(3,548		)
Bank-owned life insurance	(784		)	(993		)	(1,552		)	(1,878		)
Charitable contributions to BOKF Foundation	—			—			(427		)	—
Other, net	606			464			963			877
Total	$	37,230		$	41,423		$	74,731		$	88,519

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2014		2013		2014		2013
Percent of pretax income:
Federal statutory tax	35	%	35	%	35	%	35	%
Tax exempt revenue	(2	)	(1	)	(2	)	(1	)
Effect of state income taxes, net of federal benefit	3		3		3		2
Utilization of tax credits	(2	)	(2	)	(2	)	(1	)
Bank-owned life insurance	(1	)	(1	)	(1	)	(1	)
Charitable contributions to BOKF Foundation	—		—		—		—
Other, net	—		—		—		—
Total	33	%	34	%	33	%	34	%