Loans and Allowances for Credit Losses Part 2 (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011
Allowance for loan losses [Roll Forward]
Beginning balance	$ 215,507,000	$ 253,481,000		$ 292,971,000
Provision for loan losses	(28,073,000)	(14,654,000)		(1,040,000)
Loans charged off	(25,282,000)	(42,138,000)		(56,800,000)
Recoveries	23,244,000	18,818,000		18,350,000
Ending balance	185,396,000	215,507,000		253,481,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	1,915,000	9,261,000		14,271,000
Provision for off-balance sheet credit risk	173,000	(7,346,000)		(5,010,000)
Ending balance	2,088,000	1,915,000		9,261,000
Total provision for credit losses	(27,900,000)	(22,000,000)		(6,050,000)
Negative recovery related to invalidated settlement agreement		7,100,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	12,691,892,000	12,177,046,000
Individually measured for impairment, recorded investment	100,372,000	134,410,000
Total	12,792,264,000	12,311,456,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	156,229,000	167,087,000
Individually measured for impairment, related allowance	954,000	4,233,000
Total measured for impairment, related allowance	185,396,000	215,507,000		253,481,000
Commercial [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	65,280,000	83,443,000		104,631,000
Provision for loan losses	12,747,000	(14,950,000)		(13,830,000)
Loans charged off	(6,335,000)	(9,341,000)		(14,836,000)
Recoveries	7,488,000	6,128,000	[1]	7,478,000
Ending balance	79,180,000	65,280,000		83,443,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	475,000	7,906,000		13,456,000
Provision for off-balance sheet credit risk	(356,000)	(7,431,000)		(5,550,000)
Ending balance	119,000	475,000		7,906,000
Total provision for credit losses	12,391,000	(22,381,000)		(19,380,000)
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	7,926,461,000	7,617,445,000
Individually measured for impairment, recorded investment	16,760,000	24,467,000
Total	7,943,221,000	7,641,912,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	78,607,000	65,050,000
Individually measured for impairment, related allowance	573,000	230,000
Total measured for impairment, related allowance	79,180,000	65,280,000		83,443,000
Commercial Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	54,884,000	67,034,000		98,709,000
Provision for loan losses	(16,886,000)	(6,214,000)		(18,482,000)
Loans charged off	(5,845,000)	(11,642,000)		(15,973,000)
Recoveries	9,420,000	5,706,000		2,780,000
Ending balance	41,573,000	54,884,000		67,034,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	1,353,000	1,250,000		443,000
Provision for off-balance sheet credit risk	523,000	103,000		807,000
Ending balance	1,876,000	1,353,000		1,250,000
Total provision for credit losses	(16,363,000)	(6,111,000)		(17,675,000)
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	2,374,503,000	2,168,373,000
Individually measured for impairment, recorded investment	40,850,000	60,626,000
Total	2,415,353,000	2,228,999,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	41,440,000	51,775,000
Individually measured for impairment, related allowance	133,000	3,109,000
Total measured for impairment, related allowance	41,573,000	54,884,000		67,034,000
Residential Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	41,703,000	46,476,000		50,281,000
Provision for loan losses	(8,043,000)	3,346,000		7,968,000
Loans charged off	(5,753,000)	(10,047,000)		(14,107,000)
Recoveries	1,558,000	1,928,000		2,334,000
Ending balance	29,465,000	41,703,000		46,476,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	78,000	91,000		131,000
Provision for off-balance sheet credit risk	12,000	(13,000)		(40,000)
Ending balance	90,000	78,000		91,000
Total provision for credit losses	(8,031,000)	3,333,000		7,928,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	2,010,483,000	1,998,432,000
Individually measured for impairment, recorded investment	41,543,000	46,608,000
Total	2,052,026,000	2,045,040,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	29,217,000	40,934,000
Individually measured for impairment, related allowance	248,000	769,000
Total measured for impairment, related allowance	29,465,000	41,703,000		46,476,000
Consumer [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	9,453,000	10,178,000		12,614,000
Provision for loan losses	83,000	5,327,000		3,690,000
Loans charged off	(7,349,000)	(11,108,000)		(11,884,000)
Recoveries	4,778,000	5,056,000		5,758,000
Ending balance	6,965,000	9,453,000		10,178,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	9,000	14,000		241,000
Provision for off-balance sheet credit risk	(6,000)	(5,000)		(227,000)
Ending balance	3,000	9,000		14,000
Total provision for credit losses	77,000	5,322,000		3,463,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	380,445,000	392,796,000
Individually measured for impairment, recorded investment	1,219,000	2,709,000
Total	381,664,000	395,505,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	6,965,000	9,328,000
Individually measured for impairment, related allowance	0	125,000
Total measured for impairment, related allowance	6,965,000	9,453,000		10,178,000
Specific Allowance [Member]
Allowance for loan losses [Roll Forward]
Ending balance	157,183,000	171,320,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	12,691,892,000	12,177,046,000
Individually measured for impairment, recorded investment	100,372,000	134,410,000
Total	12,792,264,000	12,311,456,000
Related allowance [Abstract]
Collectively measured for impairment, related allowance	156,229,000	167,087,000
Individually measured for impairment, related allowance	954,000	4,233,000
Total measured for impairment, related allowance	157,183,000	171,320,000
Nonspecific allowance [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	44,187,000	46,350,000		26,736,000
Provision for loan losses	(15,974,000)	(2,163,000)		19,614,000
Loans charged off	0	0		0
Recoveries	0	0		0
Ending balance	28,213,000	44,187,000		46,350,000
Accrual for off-balance sheet credit losses [Roll Forward]
Beginning balance	0	0		0
Provision for off-balance sheet credit risk	0	0		0
Ending balance	0	0		0
Total provision for credit losses	(15,974,000)	(2,163,000)		19,614,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	0	0
Individually measured for impairment, recorded investment	0	0
Total	0	0
Related allowance [Abstract]
Collectively measured for impairment, related allowance	0	0
Individually measured for impairment, related allowance	0	0
Total measured for impairment, related allowance	$ 28,213,000	$ 44,187,000		$ 46,350,000

[1] Includes $7.1 million of negative recovery related to a refund of a settlement between BOK Financial and the City of Tulsa invalidated by the Oklahoma Supreme Court.