Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 110,265	$ 105,347
Other comprehensive income (loss) before income taxes:
Net change in unrealized gain (loss)	92,739	(97,406)
Reclassification adjustments included in earnings:
Loss (gain) on available for sale securities, net	(76)	290
Other comprehensive income (loss) before income taxes	92,663	(97,116)
Federal and state income taxes	23,609	(24,808)	[1]
Other comprehensive income (loss), net of income taxes	69,054	(72,308)
Comprehensive income	179,319	33,039
Comprehensive income attributable to non-controlling interests	(347)	(215)
Comprehensive income attributable to BOK Financial Corp. shareholders	$ 179,666	$ 33,254

[1] Calculated using a 25 percent blended federal and state statutory tax rate.