Other Borrowings (Details) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Other Borrowings [Line Items]
Balance	$ 3,069,690,000		$ 3,053,854,000		$ 2,769,748,000
Average balance	3,719,768,000		3,104,724,000		2,678,641,000
Weighted Average Interest Rate During Period	0.40%		0.65%		1.17%
US Agency Securities [Member]
Repurchase Agreements, Security Sold/Maturity [Abstract]
Amortized Cost	1,085,893,000		1,213,593,000
Market Value	1,075,821,000		1,242,314,000
Repurchase Liability	813,624,000	[1]	877,382,000	[1]
Average Rate (in hundredths)	0.05%		0.07%
US Agency Securities [Member] | Overnight [Member]
Repurchase Agreements, Security Sold/Maturity [Abstract]
Amortized Cost	1,085,893,000		1,213,593,000
Market Value	1,075,821,000		1,242,314,000
Repurchase Liability	813,624,000	[1]	877,382,000	[1]
Average Rate (in hundredths)	0.05%		0.07%
US Agency Securities [Member] | Long-term [Member]
Repurchase Agreements, Security Sold/Maturity [Abstract]
Amortized Cost	0		0
Market Value	0		0
Repurchase Liability	0	[1]	0	[1]
Average Rate (in hundredths)	0.00%		0.00%
Parent Company and other non-bank subsidiaries [Member]
Other Borrowings [Line Items]
Balance	0		10,500,000		0
Average balance	326,000		394,000		7,093,000
Weighted Average Interest Rate During Period	0.00%		1.11%		6.42%
Other borrowings, Maturities [Abstract]
2014	0
2015	0
2016	0
2017	0
2018	0
Thereafter	0
Senior Unsecured Revolving Credit Facility [Abstract]
Senior unsecured revolving credit facility, revolving period	364
Parent Company and other non-bank subsidiaries [Member] | Senior Unsecured Revolving Credit Facility [Member]
Other Borrowings [Line Items]
Balance	0		0
Other borrowings, Other Disclosures [Abstract]
Maturity date	Jun. 05, 2014
Senior Unsecured Revolving Credit Facility [Abstract]
Senior unsecured revolving credit facility, borrowing capacity	100,000,000
Senior unsecured revolving credit facility, interest rate description	defined base rate minus 1.25% or LIBOR plus 1.00% based upon the Company’s option
Senior unsecured revolving credit facility, Term loan, interest rate description	defined base rate minus 1.25% or LIBOR plus 1.25%
Senior unsecured revolving credit facility, unused capacity, commitment fee percentage	0.20%
Parent Company and other non-bank subsidiaries [Member] | Trust Preferred Debt [Member]
Other Borrowings [Line Items]
Balance					0
Weighted Average Interest Rate					0.00%
Average balance					7,093,000
Weighted Average Interest Rate During Period					6.42%
Maximum Outstanding At Any Month End					8,763,000
Parent Company and other non-bank subsidiaries [Member] | Other Borrowings [Member]
Other Borrowings [Line Items]
Balance	0		10,500,000		0
Weighted Average Interest Rate	0.00%		1.50%		0.00%
Average balance	326,000		394,000		0
Weighted Average Interest Rate During Period	0.00%		1.11%		0.00%
Maximum Outstanding At Any Month End	0		10,500,000		0
Subsidiary Bank [Member]
Other Borrowings [Line Items]
Balance	3,069,690,000		3,043,354,000		2,769,748,000
Average balance	3,719,442,000		3,104,330,000		2,671,548,000
Weighted Average Interest Rate During Period	0.41%		0.65%		1.06%
Other borrowings, Maturities [Abstract]
2014	2,705,823,000
2015	122,032,000
2016	525,000
2017	226,820,000
2018	575,000
Thereafter	13,915,000
Subsidiary Bank [Member] | Funds Purchased [Member]
Other Borrowings [Line Items]
Balance	868,081,000		1,167,416,000		1,063,318,000
Weighted Average Interest Rate	0.04%		0.05%		0.03%
Average balance	866,062,000		1,512,711,000		1,046,114,000
Weighted Average Interest Rate During Period	0.10%		0.14%		0.07%
Maximum Outstanding At Any Month End	997,536,000		1,810,793,000		1,706,893,000
Other borrowings, Other Disclosures [Abstract]
Number of days to maturity, minimum	1 day
Number of days to maturity, maximum	90 days
Subsidiary Bank [Member] | Repurchase Agreements [Member]
Other Borrowings [Line Items]
Balance	813,454,000		887,030,000		1,233,064,000
Weighted Average Interest Rate	0.05%		0.07%		0.09%
Average balance	811,996,000		1,072,650,000		1,096,615,000
Weighted Average Interest Rate During Period	0.06%		0.09%		0.12%
Maximum Outstanding At Any Month End	881,033,000		1,272,151,000		1,393,237,000
Other borrowings, Other Disclosures [Abstract]
Number of days to maturity, maximum	90 days
Accrued interest payable	0		0
Subsidiary Bank [Member] | Other Borrowings [Member]
Other Borrowings [Line Items]
Balance	1,040,353,000		641,275,000		74,485,000
Average balance	1,693,667,000		155,270,000		130,029,000
Weighted Average Interest Rate During Period	0.27%
Subsidiary Bank [Member] | Federal Home Loan Bank Advances [Member]
Other Borrowings [Line Items]
Balance	1,005,650,000		604,897,000		4,837,000
Weighted Average Interest Rate	0.19%		0.23%		0.27%
Average balance	1,661,424,000		104,925,000		45,110,000
Weighted Average Interest Rate During Period	0.20%		0.31%		0.38%
Maximum Outstanding At Any Month End	2,451,197,000		604,897,000		201,674,000
Other borrowings, Other Disclosures [Abstract]
Federal Home Loan Banks, Letters of credit issued to secure public funds	297,000,000
Unused credit available pursuant to the FHLB's collateral policies	2,300,000,000
Subsidiary Bank [Member] | GNMA Repurchase Liability [Member]
Other Borrowings [Line Items]
Balance	18,113,000		20,046,000		53,082,000
Weighted Average Interest Rate	5.50%		5.44%		6.18%
Average balance	15,741,000		33,768,000		56,142,000
Weighted Average Interest Rate During Period	5.43%		5.41%		5.79%
Maximum Outstanding At Any Month End	21,055,000		47,840,000		118,595,000
Subsidiary Bank [Member] | Other [Member]
Other Borrowings [Line Items]
Balance	16,590,000		16,332,000		16,566,000
Weighted Average Interest Rate	2.35%		5.10%		5.10%
Average balance	16,502,000		16,577,000		28,777,000
Weighted Average Interest Rate During Period	2.54%		2.91%		3.23%
Maximum Outstanding At Any Month End	17,092,000		16,761,000		45,366,000
Subsidiary Bank [Member] | Subordinated Debentures [Member]
Other Borrowings [Line Items]
Balance	347,802,000		347,633,000		398,881,000
Weighted Average Interest Rate	5.11%		2.40%		5.47%
Average balance	347,717,000		363,699,000		398,790,000
Weighted Average Interest Rate During Period	2.51%		3.79%		5.74%
Maximum Outstanding At Any Month End	347,802,000		398,897,000		398,881,000
Subsidiary Bank [Member] | Subordinated Debentures, 2007 Issuance [Member]
Other Borrowings [Line Items]
Balance	227,000,000
Other borrowings, Other Disclosures [Abstract]
Amount of debt issuance	250,000,000
Maturity date	May 15, 2017
Interest rate description	fixed rate of 5.75% through May 14, 2012 and is based on a floating rate of three-month LIBOR plus 0.69% thereafter
Subsidiary Bank [Member] | Subordinated Debentures, 2005 Issuance [Member]
Other Borrowings [Line Items]
Balance	122,000,000
Weighted Average Interest Rate	5.56%
Other borrowings, Other Disclosures [Abstract]
Amount of debt issuance	$ 150,000,000
Maturity date	Jun. 01, 2015

[1] 1 BOK Financial maintains control over the securities underlying overnight repurchase agreements and generally transfers control over securities underlying longer-term dealer repurchase agreements to the respective counterparty.