Other Comprehensive Income (Loss) (Component Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive loss before reclassifications	$ (2,182)	$ 6,551	$ 13,850	$ 6,179
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	0	0	0	0
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax	0	0	0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(2,182)	6,551	13,850	6,179
Other comprehensive income (loss)	(2,182)	6,551	13,850	6,179
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax	(2,182)	6,551	13,850	6,179
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax		0	0	0
Changes in pension plan assets and benefit obligations, Net-of-tax amount	(15,351)	(14,865)	(15,351)	(14,865)	$ 15,351	$ 15,351	$ 14,865	$ 14,865
Unrealized gains on available-for-sale securities, Net-of-tax amount	13,558	7,436	13,558	7,436	15,740	(292)	885	1,257
Total accumulated other comprehensive income (loss), Net-of-tax amount	$ (1,793)	$ (7,429)	(1,793)	$ (7,429)	$ 389	$ (15,643)	$ (13,980)	$ (13,608)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax			$ 0