Commitments and Contingent Liabilities (Details) (USD $)	Sep. 30, 2013
Parent Company [Member] | Visa Membership [Member]
Loss Contingencies [Line Items]
Number of Visa Class B Shares Owned by Entity (in shares)	251,837
Amount Deposited by Visa in Escrow for Covered Litigation	$ 150,000,000
Current Exchange Rate For Class A shares For Each Class B Share	0.4206
Cavanal Hill Funds [Member]
Loss Contingencies [Line Items]
Mutual Fund Investment in US Treasury Securities	843,000,000
Mutual Fund Investment in Cash Management	1,200,000,000
Mutual Fund Investment in Tax-Free Money Market Funds	273,000,000
The Net Asset Value of Units in Mutual Funds (per unit)	1.00
BOKF Equity, LLC [Member]
Loss Contingencies [Line Items]
Number of Private Equity Funds of which the Entity is a General Partner	2
Contingent Obligations For Additional Investments in Private Equity Funds	$ 6,400,000