Fair Value Measurements, Measured On Recurring Basis Significant Unobservable Inputs (Details) (Fair Value, Inputs, Level 3 [Member], USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Balance at beginning of period	$ 10,445,000	$ 38,847,000	$ 17,805,000	$ 40,702,000
Transfer to Level 3 from Level 2	0	0	0	0
Purchases and capital calls	0	0	0	0
Redemptions and distributions	0	0	(7,487,000)	(98,000)
Other comprehensive gain (loss)	(252,000)	2,193,000	110,000	436,000
Balance at end of period	10,193,000	39,671,000	10,193,000	39,671,000
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member] | Mortgage banking revenue [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member] | Gain (loss) on assets [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0	0	0	0
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member] | Loss on available for sale securities, net [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		(235,000)
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member] | Other-than-temporary impairment losses [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings		(1,369,000)		(1,369,000)
Available-for-sale Securities [Member] | Municipal and other tax-exempt securities [Member] | Charitable Contributions to BOKF Foundation [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Other debt securities [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Balance at beginning of period	4,231,000	5,193,000	4,712,000	5,399,000
Transfer to Level 3 from Level 2	0	0	0	0
Purchases and capital calls	0	0	0	0
Redemptions and distributions	0	(500,000)	(500,000)	(500,000)
Other comprehensive gain (loss)	(81,000)	19,000	(62,000)	(187,000)
Balance at end of period	4,150,000	4,712,000	4,150,000	4,712,000
Available-for-sale Securities [Member] | Other debt securities [Member] | Mortgage banking revenue [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Other debt securities [Member] | Gain (loss) on assets [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0	0	0	0
Available-for-sale Securities [Member] | Other debt securities [Member] | Loss on available for sale securities, net [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Other debt securities [Member] | Other-than-temporary impairment losses [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings		0		0
Available-for-sale Securities [Member] | Other debt securities [Member] | Charitable Contributions to BOKF Foundation [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Balance at beginning of period	0	2,247,000	4,207,000	2,161,000
Transfer to Level 3 from Level 2	0	0	0
Purchases and capital calls	0	0	0	0
Redemptions and distributions	0	0	0	0
Other comprehensive gain (loss)	0	1,960,000	(1,787,000)	2,046,000
Balance at end of period	0	4,207,000	0	4,207,000
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member] | Mortgage banking revenue [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member] | Gain (loss) on assets [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0	0	0	0
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member] | Loss on available for sale securities, net [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member] | Other-than-temporary impairment losses [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings		0		0
Available-for-sale Securities [Member] | Equity securities and mutual funds [Member] | Charitable Contributions to BOKF Foundation [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		(2,420,000)
Residential Mortgage Loans Held for Sale [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Balance at beginning of period	0		0
Transfer to Level 3 from Level 2	7,764,000		7,764,000
Purchases and capital calls	0		0
Redemptions and distributions	0		0
Other comprehensive gain (loss)	0		0
Balance at end of period	7,376,000		7,376,000
Residential Mortgage Loans Held for Sale [Member] | Mortgage banking revenue [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	(388,000)		(388,000)
Residential Mortgage Loans Held for Sale [Member] | Gain (loss) on assets [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Residential Mortgage Loans Held for Sale [Member] | Loss on available for sale securities, net [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Residential Mortgage Loans Held for Sale [Member] | Charitable Contributions to BOKF Foundation [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Other Assets [Member] | Private equity funds [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Balance at beginning of period	27,833,000	28,379,000	27,341,000	28,169,000
Transfer to Level 3 from Level 2	0	0	0	0
Purchases and capital calls	505,000	567,000	930,000	1,207,000
Redemptions and distributions	(1,994,000)	(1,589,000)	(5,175,000)	(3,424,000)
Other comprehensive gain (loss)	0	0	0	0
Balance at end of period	27,118,000	27,799,000	27,118,000	27,799,000
Other Assets [Member] | Private equity funds [Member] | Mortgage banking revenue [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Other Assets [Member] | Private equity funds [Member] | Gain (loss) on assets [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	774,000	442,000	4,022,000	1,847,000
Other Assets [Member] | Private equity funds [Member] | Loss on available for sale securities, net [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	0		0
Other Assets [Member] | Private equity funds [Member] | Other-than-temporary impairment losses [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings		0		0
Other Assets [Member] | Private equity funds [Member] | Charitable Contributions to BOKF Foundation [Member]
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward]
Gain (loss) recognized in earnings	$ 0		$ 0