Derivative Financial Instruments (Schedule of Derivative Instruments in Statement of Financial Position, Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Other Assets [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	$ 58,640	$ 48,391
Other Liabilities [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	38,939	32,180
Designated as Hedging Instrument [Member] | Other Assets [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	2,507	4,481
Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	1,359	4,598
Not Designated as Hedging Instrument [Member] | Other Assets [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	58,304	48,209
Not Designated as Hedging Instrument [Member] | Other Assets [Member] | Other Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	183	0
Not Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Interest Rate Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	38,619	31,915
Not Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Other Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	75	7
Not Designated as Hedging Instrument [Member] | Credit Default Swap, Selling Protection [Member] | Other Assets [Member] | Credit Risk Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0	0
Not Designated as Hedging Instrument [Member] | Credit Default Swap, Selling Protection [Member] | Other Liabilities [Member] | Credit Risk Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	245	258
Not Designated as Hedging Instrument [Member] | Credit Default Swap, Buying Protection [Member] | Other Assets [Member] | Credit Risk Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	153	182
Not Designated as Hedging Instrument [Member] | Credit Default Swap, Buying Protection [Member] | Other Liabilities [Member] | Credit Risk Contract [Member]
Derivative [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	$ 0	$ 0