Fair Value Of Assets And Liabilities (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($)	Sep. 30, 2016		Dec. 31, 2015	Sep. 30, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	$ 1,320,535,000		$ 881,450,000	$ 1,229,180,000
Loans held-for-sale	22,750,000			26,789,000
Securities available for sale, Fair Value	4,027,594,000	[1]	$ 3,929,846,000	3,673,641,000	[2]
Total other assets	193,874,000			180,513,000
Total assets	5,403,396,000			4,954,410,000
Total other liabilities	144,829,000			140,965,000
Total liabilities	847,055,000			929,528,000
Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	3,866,237,000			3,517,928,000
Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	0			0
Securities available for sale, Fair Value	24,636,000			25,840,000
Total other assets	43,651,000			42,307,000
Total assets	68,287,000			68,147,000
Total other liabilities	10,924,000			15,921,000
Total liabilities	10,924,000			15,921,000
Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	214,000			0
Securities available for sale, Fair Value	3,841,601,000			3,489,142,000
Total other assets	148,977,000			136,213,000
Total assets	5,308,543,000			4,849,932,000
Total other liabilities	127,365,000			120,234,000
Total liabilities	829,591,000			908,797,000
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans held-for-sale	22,536,000			26,789,000
Securities available for sale, Fair Value	0			2,946,000
Total other assets	1,246,000			1,993,000
Total assets	26,566,000			36,331,000
Total other liabilities	6,540,000			4,810,000
Total liabilities	6,540,000			4,810,000
U.S. treasuries
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	100,000			100,000
U.S. treasuries | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	0			0
U.S. treasuries | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	100,000			100,000
U.S. treasuries | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	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, Fair Value	1,940,357,000			945,951,000
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, Fair Value	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, Fair Value	1,940,357,000			945,951,000
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, Fair Value	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, Fair Value	1,901,144,000			2,535,436,000
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, Fair Value	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, Fair Value	1,901,144,000			2,535,436,000
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, Fair Value	0			0
Other U.S. Government Agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				1,446,000
Other U.S. Government Agencies | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				0
Other U.S. Government Agencies | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				0
Other U.S. Government Agencies | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				1,446,000
States And Municipalities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				9,155,000
States And Municipalities | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				0
States And Municipalities | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				7,655,000
States And Municipalities | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value				1,500,000
Equity, Mutual Funds, And Other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	24,636,000			25,840,000
Equity, Mutual Funds, And Other | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	24,636,000			25,840,000
Equity, Mutual Funds, And Other | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Securities available for sale, Fair Value	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, Fair Value	0			0
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	1,246,000			1,993,000
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	1,246,000			1,993,000
Deferred Compensation Assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	31,892,000			25,972,000
Deferred Compensation Assets | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	31,892,000			25,972,000
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	11,759,000			16,335,000
Total other liabilities	10,924,000			15,921,000
Derivatives, Forwards And Futures | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	11,759,000			16,335,000
Total other liabilities	10,924,000			15,921,000
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	148,972,000			136,121,000
Total other liabilities	127,352,000			120,234,000
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	148,972,000			136,121,000
Total other liabilities	127,352,000			120,234,000
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	5,000			92,000
Total other liabilities	6,553,000			4,810,000
Derivatives, Other | 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, Other | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	5,000			92,000
Total other liabilities	13,000			0
Derivatives, Other | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total other assets	0			0
Total other liabilities	6,540,000			4,810,000
Fixed Income
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	1,317,756,000			1,224,582,000
Total trading liabilities - fixed income	702,226,000			788,563,000
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	1,317,751,000			1,224,577,000
Total trading liabilities - fixed income	702,226,000			788,563,000
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	110,538,000			97,211,000
Total trading liabilities - fixed income	508,895,000			478,759,000
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	110,538,000			97,211,000
Total trading liabilities - fixed income	508,895,000			478,759,000
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	478,756,000			265,290,000
Total trading liabilities - fixed income	199,000			1,481,000
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	478,756,000			265,290,000
Total trading liabilities - fixed income	199,000			1,481,000
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	266,284,000			283,927,000
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	266,284,000			283,927,000
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	121,460,000			113,739,000
Total trading liabilities - fixed income	7,934,000			6,482,000
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	121,460,000			113,739,000
Total trading liabilities - fixed income	7,934,000			6,482,000
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	93,448,000			65,255,000
Total trading liabilities - fixed income	143,000
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	93,448,000			65,255,000
Total trading liabilities - fixed income	143,000
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 | Trading Loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities				16,943,000
Fixed Income | Trading Loans | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities				0
Fixed Income | Trading Loans | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities				16,943,000
Fixed Income | Trading Loans | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities				0
Fixed Income | Corporate And Other Debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Trading securities	246,158,000			381,475,000
Total trading liabilities - fixed income	185,055,000			301,841,000
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	246,153,000			381,470,000
Total trading liabilities - fixed income	185,055,000			301,841,000
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	1,112,000			742,000
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	1,112,000			742,000
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	2,779,000			4,598,000
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	$ 2,779,000			$ 4,598,000

[1] Includes $ 3.3 billion of securities pledged to secure public deposits, securities sold under agreements to repurchase, and for other purposes.

[2] Includes $ 2.9 billion of securities pledged to secure public deposits, securities sold under agreements to repu rchase, and for other purposes .