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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The net result for the period of deducting operating expenses from operating revenues.

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Business Segment Information (Schedule Of Reconciliation Of Operating Profit (Loss) From Segments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Segment Information [Abstract]
Segment profits	$ 128,729us-gaap_GrossProfit	$ 129,835us-gaap_GrossProfit	$ 116,732us-gaap_GrossProfit	$ 104,569us-gaap_GrossProfit	$ 96,248us-gaap_GrossProfit	$ 102,054us-gaap_GrossProfit	$ 103,211us-gaap_GrossProfit	$ 93,303us-gaap_GrossProfit	$ 479,865us-gaap_GrossProfit	$ 394,816us-gaap_GrossProfit	$ 472,300us-gaap_GrossProfit
General and administrative expenses									(167,301)us-gaap_GeneralAndAdministrativeExpense	(171,439)us-gaap_GeneralAndAdministrativeExpense	(183,274)us-gaap_GeneralAndAdministrativeExpense
Depreciation and amortization									(217,480)	(209,747)	(187,083)
Loss on disposal of assets									(1,974)us-gaap_GainLossOnDispositionOfAssets	(2,873)us-gaap_GainLossOnDispositionOfAssets	(3,334)us-gaap_GainLossOnDispositionOfAssets
Goodwill Impairment									(34,703)us-gaap_GoodwillImpairmentLoss
Operating income									$ 58,407us-gaap_OperatingIncomeLoss	$ 10,757us-gaap_OperatingIncomeLoss	$ 98,609us-gaap_OperatingIncomeLoss