Derivatives and Hedging Activities (Derivative Financial Instruments included in OCI and Current Earnings) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	[1]	$ 268	$ (91)	$ 525	$ (264)
Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings		0	0
Gain (loss) reclassified from OCI into interest income or interest expense (effective portion)			(91)	525	(264)
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Other income		(146)	(33)	13	61
Interest Expense [Member] | Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings		0	0
Other expense | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Other income		3	7	27	7
Changes in fair value of mortgage derivatives | Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Excluded Component, Gain (Loss), Recognized in Earnings		0	0
Changes in fair value of mortgage derivatives | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Other income		(10)	(7)	(28)	(17)
Total | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Mortgage banking income		(139)	(33)	14	71
Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent		$ (405)	$ 109	$ (302)	$ 8

[1] Includes the amortization of the remaining balance of a realized but unrecognized gain, net of tax, from the termination of interest rate swaps in 2009. The original gain of $1.4 million, net of tax, is being recognized in earnings through December 2018, the original maturity date of the swap. The balance of this gain has amortized to $34,000 and $137,000 at September 30, 2018 and December 31, 2017, respectively.