Accounting For Income Taxes (Schedule Of Components Of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of Income Tax Expense (Benefit) [Line Items]
Current income tax expense (benefit)	$ 13,101	$ (46,457)	$ 12,212
Deferred income tax expense	69,657	124,543	55,237
Total income tax expense	$ 82,758	$ 78,086	$ 67,449

[Line Items] for Components of Income Tax Expense (Benefit) [Table]

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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

+ References

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-Publisher FASB
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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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