Accounting Policies (Summary Of The Most Significant Impacts Of The New Accounting Guidance) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Increase in operating activities		$ 252,150	$ 238,188
Decrease in financing activities		129,958	144,944
Accounting Standards Update 2016-09 [Member]
Effective Income Tax Rate Reconciliation, Deduction, Amount	$ 3,800	$ 22,100
Weighted Average Number Diluted Shares Outstanding Adjustment	450,000	450,000
Accounting Standards Update 2016-09 [Member] \| Tax Benefits Related To Share-based Payments At Settlement Classified As Operating Cash Flows Instead Of Financing Cash Flows [Member]
Increase in operating activities		$ 22,100
Decrease in financing activities		22,100
Accounting Standards Update 2016-09 [Member] \| Cash Payments To Tax Authorities For Shares Withheld To Meet Tax Withholding Requirements On Restricted Stock Units Are Classified As Financing Cash Flow Instead Of Operating Cash Flow [Member]
Increase in operating activities		7,800	3,700
Decrease in financing activities		$ 7,800	$ 3,700

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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