Discontinued Operations (Summarized Income (Loss) from Discontinued Operations, Net Of Tax) (Details 3) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating revenues						$ 397,404	$ 845,114
Operating costs and expenses						(325,379)	(660,180)
Operating income						72,025	184,934
Non-operating (expense) income						(1,288)	74,196
Income from discontinued operations						70,737	259,130
Provision for income taxes						27,783	98,207
Net Income from Discontinued Operations						42,954	160,923
(Loss) gain on dispositions of discontinued operations						(732)	351,133
Provision (benefit) for income taxes on dispositions of discontinued operations						52	(15,801)
Income from Discontinued Operations, Net of Tax	$ 0	$ 379	$ 18,502	$ 23,289	$ 0	$ 42,170	$ 527,857