Federal and State Income Taxes (Tables)

3 Months Ended

Mar. 31, 2015

Income Tax Disclosure [Abstract]

Reconciliation of income (loss) to income tax expense

	Three Months Ended March 31,
	2015			2014
Amount:
Federal statutory tax	$	39,717		$	40,768
Tax exempt revenue	(2,246		)	(1,991		)
Effect of state income taxes, net of federal benefit	2,615			2,870
Utilization of tax credits:
Low-income housing tax credit, net of amortization	(757		)	(991		)
Other tax credits	(521		)	(381		)
Bank-owned life insurance	(804		)	(768		)
Charitable contributions to BOKF Foundation	—			(427		)
Other, net	380			357
Total	$	38,384		$	39,437

	Three Months Ended March 31,
	2015		2014
Percent of pretax income:
Federal statutory tax	35.0	%	35.0	%
Tax exempt revenue	(2.0	)	(1.7	)
Effect of state income taxes, net of federal benefit	2.3		2.5
Utilization of tax credits:
Low-income housing tax credit, net of amortization	(0.7	)	(0.9	)
Other tax credits	(0.5	)	(0.3	)
Bank-owned life insurance	(0.7	)	(0.7	)
Charitable contributions to BOKF Foundation	—		(0.4	)
Other, net	0.4		0.4
Total	33.8	%	33.9	%