Fair Value Of Assets And Liabilities (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($)	Jun. 30, 2015		Dec. 31, 2014	Jun. 30, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 1,133,490,000		$ 1,194,391,000	$ 1,150,280,000
Loans held-for-sale	26,525,000			232,487,000
Securities available for sale	3,648,860,000	[1]	$ 3,556,613,000	3,576,542,000	[2]
Total other assets	144,729,000			190,124,000
Total assets	4,797,610,000			4,990,631,000
Total other liabilities	109,815,000			138,336,000
Total liabilities	842,379,000			844,455,000
Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	3,492,866,000			3,417,740,000
Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	0			0
Securities available for sale	25,825,000			25,995,000
Total other assets	32,640,000			29,979,000
Total assets	58,465,000			55,974,000
Total other liabilities	4,788,000			5,310,000
Total liabilities	4,788,000			5,310,000
Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	0			0
Securities available for sale	3,463,981,000			3,385,884,000
Total other assets	109,931,000			156,948,000
Total assets	4,702,473,000			4,686,691,000
Total other liabilities	100,217,000			128,301,000
Total liabilities	832,781,000			834,420,000
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	26,525,000			232,487,000
Securities available for sale	3,060,000			5,861,000
Total other assets	2,158,000			3,197,000
Total assets	36,672,000			247,966,000
Total other liabilities	4,810,000			4,725,000
Total liabilities	4,810,000			4,725,000
U.S. treasuries
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	100,000			39,999,000
U.S. treasuries | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
U.S. treasuries | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	100,000			39,999,000
U.S. treasuries | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Government Agency Issued Mortgage-Backed Securities ("MBS")
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	830,640,000			762,842,000
Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	830,640,000			762,842,000
Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Government Agency Issued Collateralized Mortgage Obligations ("CMO")
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	2,625,286,000			2,569,388,000
Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	2,625,286,000			2,569,388,000
Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Other U.S. Government Agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	1,560,000			2,061,000
Other U.S. Government Agencies | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Other U.S. Government Agencies | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Other U.S. Government Agencies | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	1,560,000			2,061,000
States And Municipalities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	9,455,000			15,155,000
States And Municipalities | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
States And Municipalities | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	7,955,000			13,655,000
States And Municipalities | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	1,500,000			1,500,000
Venture Capital Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale				2,300,000
Venture Capital Investments | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale				0
Venture Capital Investments | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale				0
Venture Capital Investments | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale				2,300,000
Equity, Mutual Funds, And Other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	25,825,000			25,995,000
Equity, Mutual Funds, And Other | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	25,825,000			25,995,000
Equity, Mutual Funds, And Other | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Equity, Mutual Funds, And Other | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale	0			0
Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	2,158,000			3,197,000
Mortgage servicing rights | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Mortgage servicing rights | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Mortgage servicing rights | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	2,158,000			3,197,000
Deferred Compensation Assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	27,341,000			24,860,000
Deferred Compensation Assets | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	27,341,000			24,860,000
Deferred Compensation Assets | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Deferred Compensation Assets | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Derivatives, Forwards And Futures
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	5,299,000			5,119,000
Total other liabilities	4,788,000			5,310,000
Derivatives, Forwards And Futures | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	5,299,000			5,119,000
Total other liabilities	4,788,000			5,310,000
Derivatives, Forwards And Futures | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Forwards And Futures | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Interest Rate Contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	109,929,000			156,948,000
Total other liabilities	100,191,000			128,297,000
Derivatives, Interest Rate Contracts | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Interest Rate Contracts | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	109,929,000			156,948,000
Total other liabilities	100,191,000			128,297,000
Derivatives, Interest Rate Contracts | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	0			0
Derivatives, Other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	2,000
Total other liabilities	4,836,000			4,729,000
Derivatives, Other | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0
Total other liabilities	0			0
Derivatives, Other | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	2,000
Total other liabilities	26,000			4,000
Derivatives, Other | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0
Total other liabilities	4,810,000			4,725,000
Fixed Income
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,128,566,000			1,143,864,000
Total trading liabilities - fixed income	732,564,000			706,119,000
Fixed Income | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,128,561,000			1,143,859,000
Total trading liabilities - fixed income	732,564,000			706,119,000
Fixed Income | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5,000			5,000
Total trading liabilities - fixed income	0			0
Fixed Income | U.S. treasuries
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	109,998,000			235,389,000
Total trading liabilities - fixed income	406,879,000			479,210,000
Fixed Income | U.S. treasuries | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | U.S. treasuries | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	109,998,000			235,389,000
Total trading liabilities - fixed income	406,879,000			479,210,000
Fixed Income | U.S. treasuries | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Government Agency Issued Mortgage-Backed Securities ("MBS")
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	327,082,000			195,911,000
Total trading liabilities - fixed income	1,486,000			1,092,000
Fixed Income | Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	327,082,000			195,911,000
Total trading liabilities - fixed income	1,486,000			1,092,000
Fixed Income | Government Agency Issued Mortgage-Backed Securities ("MBS") | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Government Agency Issued Collateralized Mortgage Obligations ("CMO")
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	146,675,000			175,799,000
Fixed Income | Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Fixed Income | Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	146,675,000			175,799,000
Fixed Income | Government Agency Issued Collateralized Mortgage Obligations ("CMO") | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Fixed Income | Other U.S. Government Agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	83,416,000			71,228,000
Total trading liabilities - fixed income	25,036,000			11,167,000
Fixed Income | Other U.S. Government Agencies | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Other U.S. Government Agencies | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	83,416,000			71,228,000
Total trading liabilities - fixed income	25,036,000			11,167,000
Fixed Income | Other U.S. Government Agencies | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | States And Municipalities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	64,597,000			41,144,000
Total trading liabilities - fixed income				3,216,000
Fixed Income | States And Municipalities | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income				0
Fixed Income | States And Municipalities | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	64,597,000			41,144,000
Total trading liabilities - fixed income				3,216,000
Fixed Income | States And Municipalities | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income				0
Fixed Income | Corporate And Other Debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	393,196,000			402,353,000
Total trading liabilities - fixed income	299,163,000			211,434,000
Fixed Income | Corporate And Other Debt | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Total trading liabilities - fixed income	0			0
Fixed Income | Corporate And Other Debt | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	393,191,000			402,348,000
Total trading liabilities - fixed income	299,163,000			211,434,000
Fixed Income | Corporate And Other Debt | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	5,000			5,000
Total trading liabilities - fixed income	0			0
Fixed Income | Equity, Mutual Funds, And Other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	3,602,000			22,040,000
Fixed Income | Equity, Mutual Funds, And Other | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Fixed Income | Equity, Mutual Funds, And Other | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	3,602,000			22,040,000
Fixed Income | Equity, Mutual Funds, And Other | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	4,924,000			6,416,000
Mortgage Banking | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	4,924,000			6,416,000
Mortgage Banking | Certificated Principal Only
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	3,740,000			4,707,000
Mortgage Banking | Certificated Principal Only | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Certificated Principal Only | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Certificated Principal Only | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	3,740,000			4,707,000
Mortgage Banking | Interest Only Trading Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	78,000			322,000
Mortgage Banking | Interest Only Trading Securities | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Interest Only Trading Securities | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Interest Only Trading Securities | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	78,000			322,000
Mortgage Banking | Subordinated Bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,106,000			1,387,000
Mortgage Banking | Subordinated Bonds | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Subordinated Bonds | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	0			0
Mortgage Banking | Subordinated Bonds | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 1,106,000			$ 1,387,000

[1] Includes $ 3.2 billion of securities pledged to secure public deposits, securities sold under agreements to repurchase, and for other purposes.

[2] Includes $ 3.4 billion of securities pledged to secure public deposits, securities sold under agreements to repu rchase, and for other purposes .