Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019		Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 137,780	$ 115,155	$ 248,045		$ 220,502
Other comprehensive income (loss) before income taxes:
Net change in unrealized gain (loss)	135,417	(33,117)	228,156		(130,523)
Reclassification adjustments included in earnings:
Loss (gain) on available for sale securities, net	(1,029)	762	(1,105)		1,052
Other comprehensive income (loss) before income taxes	134,388	(32,355)	227,051		(129,471)
Federal and state income taxes	32,288	(8,241)	55,897	[1]	(33,049)	[1]
Other comprehensive income (loss), net of income taxes	102,100	(24,114)	171,154		(96,422)
Comprehensive income	239,880	91,041	419,199		124,080
Comprehensive income attributable to non-controlling interests	217	783	(130)		568
Comprehensive income attributable to BOK Financial Corp. shareholders	$ 239,663	$ 90,258	$ 419,329		$ 123,512

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