Other Comprehensive Income (Loss) (Component Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	$ 4,352	$ (8,231)	$ 16,032	$ (372)
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	4,352	(8,231)	16,032	(372)
Other comprehensive income (loss)	4,352	(8,231)	16,032	(372)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax	4,352	(8,231)	16,032	(372)
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	15,740	885	15,740	885	11,388	(292)	9,116	1,257
Total accumulated other comprehensive income (loss), Net-of-tax amount	$ 389	$ (13,980)	389	$ (13,980)	$ (3,963)	$ (15,643)	$ (5,749)	$ (13,608)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax			$ 0