Parent Company Only Financial Statements Parent Company Only Financial Statements, Condensed Income Statements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Income Statements, Captions [Line Items]
Interest expense	$ 180,722	$ 61,896	$ 160,556
Other operating expense	1,164,480	1,177,708	1,164,308
Other gains (losses), net	123	63,742	6,046
Federal and state income taxes	139,864	179,775	128,793
Net income attributable to BOK Financial Corp. shareholders	520,273	618,121	435,030
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Total revenue	273,142	492,665	205,097
Interest expense	6,490	10,535	13,944
Other operating expense	3,005	2,914	2,697
Total expense	9,495	13,449	16,641
Net income before taxes, other losses, net, and equity in undistributed income of subsidiaries	263,647	479,216	188,456
Other gains (losses), net	(4,279)	(3,415)	1,465
Net income before taxes and equity in undistributed income of subsidiaries	259,368	475,801	189,921
Federal and state income taxes	(1,776)	(4,202)	(4,502)
Net income before equity in undistributed income of subsidiaries	261,144	480,003	194,423
Equity in undistributed income of bank subsidiaries	300,330	126,380	276,217
Equity in undistributed income of non-bank subsidiaries	(41,201)	11,738	(35,610)
Net income attributable to BOK Financial Corp. shareholders	520,273	618,121	435,030
Parent Company [Member] | Dividends, interest and fees received from bank susidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total revenue	228,689	483,868	179,140
Parent Company [Member] | Dividends, interest and fees received from non-bank subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total revenue	43,281	8,030	25,050
Parent Company [Member] | Other revenue [Member]
Condensed Income Statements, Captions [Line Items]
Total revenue	$ 1,172	$ 767	$ 907