Derivative Financial Instruments (Derivatives not Designated as Hedging Instruments, Effect in Statements of Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	$ 0	$ 0	$ 0	$ 0
Interest Rate Commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	(432)	326	139	603
Commitments to sell mortgage loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	1,410	(753)	470	(1,066)
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	1,695	(464)	1,971	(240)
Not Designated as Hedging Instrument [Member] | Interest Rate Commitments [Member] | Net gains on loan sales and commissions on loans originated for others [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	(432)	326	139	603
Not Designated as Hedging Instrument [Member] | Commitments to sell mortgage loans [Member] | Net gains on loan sales and commissions on loans originated for others [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	1,410	(753)	470	(1,066)
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member] | Net gains (losses) on interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	(1,365)	1,120	2,268	2,150
Not Designated as Hedging Instrument [Member] | Mirror swaps with counterparties [Member] | Net gains (losses) on interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	2,118	(1,157)	(718)	(1,927)
Not Designated as Hedging Instrument [Member] | Risk participation-out agreement [Member] | Net gains (losses) on interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	$ (36)	$ 0	$ (188)	$ 0