Income Taxes (Components Of Net Deferred Income Tax Liability/Asset) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred income tax liabilities [Abstract]
Property, plant and equipment basis differences	$ 2,451,231	$ 1,950,720
Intangibles	1,076,456	885,661
Other, net	23,926us-gaap_DeferredTaxLiabilitiesOther	25,954us-gaap_DeferredTaxLiabilitiesOther
Gross deferred income tax liability	3,551,613us-gaap_DeferredTaxLiabilities	2,862,335us-gaap_DeferredTaxLiabilities
Deferred income tax assets [Abstract]
Pension liability	247,490	216,890
Tax operating loss carryforward	162,085	130,733
Employee benefits	304,044	161,493
State tax liability	(642)us-gaap_DeferredTaxAssetsStateTaxes	(642)us-gaap_DeferredTaxAssetsStateTaxes
Accrued expenses	54,813	26,223
Allowance for doubtful accounts	16,078	11,957
Other, net	40,016us-gaap_DeferredTaxAssetsOther	42,915us-gaap_DeferredTaxAssetsOther
Gross deferred income tax asset	823,884us-gaap_DeferredTaxAssetsGross	589,569us-gaap_DeferredTaxAssetsGross
Less: Valuation allowance	(139,937)	(112,671)
Net deferred income tax asset	683,947us-gaap_DeferredTaxAssetsNet	476,898us-gaap_DeferredTaxAssetsNet
Deferred tax assets and liabilities are reflected in the following captions on the consolidated balance sheet [Abstract]
Deferred income taxes	2,938,907	2,417,108
Income taxes and other current assets	(71,241)us-gaap_DeferredTaxAssetsNetCurrent	(31,671)us-gaap_DeferredTaxAssetsNetCurrent
Net deferred income tax liability	$ 2,867,666us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 2,385,437us-gaap_DeferredTaxAssetsLiabilitiesNet

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