Derivative Instruments And Hedging Strategies (Fair Values Of Derivative Instruments) (Details) (USD $) In Thousands	Sep. 30, 2011
Derivative [Line Items]
Derivative Asset	$ 6,650
Derivative Liability	24,167
Derivatives Designated As Hedging Instruments[Member] | Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Derivative Asset
Derivative Liability	5,873
Derivatives Not Designated As Hedging Instruments [Member] | Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Derivative Asset
Derivative Liability	3,766
Options On Equities And Equity Indices [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Derivative Asset	1,127
Derivative Liability	958
Derivatives Not Designated As Hedging Instruments [Member] | Forward Currency Exchange, Option And Future Contracts [Member]
Derivative [Line Items]
Derivative Asset	635
Derivative Liability	1,765
Commodity Swap, Option And Future Contracts, Exchange Traded [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Derivative Asset	1,774
Derivative Liability	2,147
Commodity Swap, Option And Future Contracts, Non-Exchange traded [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Derivative Asset	3,114
Derivative Liability	1,403
U.S. Treasury Notes, Rate-Locks And Bond Future And Option Contracts [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Derivative Liability	8,255
Derivatives Designated As Hedging Instruments[Member]
Derivative [Line Items]
Derivative Asset
Derivative Liability	5,873
Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Derivative Asset	6,650
Derivative Liability	$ 18,294