Comprehensive Income (Loss) (Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Accumulated other comprehensive income (loss), beginning balance	$ (4,146)	$ (5,107)
Other comprehensive income (loss) before reclassifications	(7,839)	2,075
Amounts reclassified from accumulated other comprehensive income	12	250
Net current-period other comprehensive income (loss)	(7,827)	2,325
Accumulated other comprehensive income (loss), ending balance	(11,973)	(2,782)
Unrealized gain (loss) on securities available for sale [Member]
Accumulated other comprehensive income (loss), beginning balance	(1,694)	(1,947)
Other comprehensive income (loss) before reclassifications	(7,839)	2,075
Amounts reclassified from accumulated other comprehensive income		148
Net current-period other comprehensive income (loss)	(7,839)	2,223
Accumulated other comprehensive income (loss), ending balance	(9,533)	276
Additional pension asset (liability) [Member]
Accumulated other comprehensive income (loss), beginning balance	(2,452)	(3,160)
Other comprehensive income (loss) before reclassifications
Amounts reclassified from accumulated other comprehensive income	12	102
Net current-period other comprehensive income (loss)	12	102
Accumulated other comprehensive income (loss), ending balance	$ (2,440)	$ (3,058)