Derivatives (Derivatives Associated With Interest Rate Risk Management Activities) (Details) (USD $) In Thousands, unless otherwise specified						3 Months Ended				9 Months Ended						3 Months Ended				9 Months Ended				3 Months Ended				9 Months Ended				3 Months Ended				9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Sep. 30, 2013 Customer Interest Rate Contracts [Member]	Sep. 30, 2012 Customer Interest Rate Contracts [Member]	Sep. 30, 2013 Customer Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2012 Customer Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2013 Customer Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2012 Customer Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2013 Offsetting Upstream Interest Rate Contracts [Member]	Sep. 30, 2012 Offsetting Upstream Interest Rate Contracts [Member]	Sep. 30, 2013 Offsetting Upstream Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2012 Offsetting Upstream Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2013 Offsetting Upstream Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2012 Offsetting Upstream Interest Rate Contracts [Member] Customer Interest Rate Contracts Hedging [Member] Hedging Instruments And Hedged Items [Member]		Sep. 30, 2013 Interest Rate Swap [Member] Debt [Member] Hedging Instruments [Member]		Sep. 30, 2012 Interest Rate Swap [Member] Debt [Member] Hedging Instruments [Member]		Sep. 30, 2013 Interest Rate Swap [Member] Debt [Member] Hedging Instruments [Member]		Sep. 30, 2012 Interest Rate Swap [Member] Debt [Member] Hedging Instruments [Member]		Sep. 30, 2013 Long Term Debt [Member] Debt [Member] Hedged Items [Member]		Sep. 30, 2012 Long Term Debt [Member] Debt [Member] Hedged Items [Member]		Sep. 30, 2013 Long Term Debt [Member] Debt [Member] Hedged Items [Member]		Sep. 30, 2012 Long Term Debt [Member] Debt [Member] Hedged Items [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional				$ 1,742,060	$ 1,439,306	$ 801,260	[1]	$ 975,213	[1]	$ 801,260	[1]	$ 975,213	[1]	$ 1,742,060	$ 1,439,306	$ 817,901	[1]	$ 975,213	[1]	$ 817,901	[1]	$ 975,213	[1]	$ 1,254,000	[2]	$ 1,604,000	[2]	$ 1,254,000	[2]	$ 1,604,000	[2]
Assets				88,154	137,958	34,703	[1]	61,984	[1]	34,703	[1]	61,984	[1]	6,880	923	2,453	[1]	362	[1]	2,453	[1]	362	[1]	66,049	[2]	111,240	[2]	66,049	[2]	111,240	[2]
Liabilities				6,880	923	2,452	[1]	362	[1]	2,452	[1]	362	[1]	88,154	137,958	35,203	[1]	63,384	[1]	35,203	[1]	63,384	[1]	19,622	[2]	0	[2]	19,622	[2]	0	[2]
Gains/(Losses)						(1,464)	[1]	(3,971)	[1]	(22,673)	[1]	(7,554)	[1]			1,465	[1]	4,071	[1]	23,374	[1]	8,254	[1]	(6,430)	[2]	(2,481)	[2]	(48,777)	[2]	(15,642)	[2]
Term borrowings	1,771,288	2,226,482	2,263,238																													1,254,000	[2],[3]	1,604,000	[2],[3]	1,254,000	[2],[3]	1,604,000	[2],[3]
Gains/(Losses) related to term borrowings																																$ 6,430	[2],[4]	$ 2,481	[2],[4]	$ 48,777	[2],[4]	$ 15,642	[2],[4]

[1] Gains/losses included in the Other expense section of the Consolidated Condensed Statements of Income.

[2] Gains/losses included in the All other income and commissions section of the Consolidated Condensed Statements of Income.

[3] Represents par value of term borrowings being hedged.

[4] Represents gains and losses attributable to changes in fair value due to interest rate risk as designated in ASC 815-20 hedging relationships.