Accumulated Other Comprehensive Loss (Schedule of Amounts Reclassified from AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains on securities transactions, net	$ (62)	$ 107	$ (28)	$ 247
Provision for federal income taxes	(300)	(287)	(535)	(544)
Reclassifications for the period	2,126	1,872	4,947	3,699
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Unrealized Gains (Losses) on Securities Available-for-Sale [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains on securities transactions, net	(62)	107	28	247
Provision for federal income taxes	13	(36)	(6)	(84)
Reclassifications for the period	$ (49)	$ 71	$ 22	$ 163

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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