Pension And Other Postretirement Benefits (Schedule Of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 2,079	$ 2,078	$ 2,079	$ 1,808	$ 6,236	$ 5,423
Interest cost	7,411	7,408	7,408	7,788	22,227	23,365
Expected return on assets	(11,204)	$ (11,206)	$ (11,206)	(10,474)	(33,616)	(31,420)
Amortization of prior service cost	1,217			1,214	3,650	3,640
Amortization of actuarial loss	3,470			2,428	10,420	7,283
ASC 715 settlement accounting re-actuarial valuation - supplemental plan	206			0	206	0
Net periodic benefit cost	$ 3,179			$ 2,764	$ 9,123	$ 8,291