Summary of Significant Accounting Policies (Calculation Of Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Accounting Policies [Abstract]
Basic earnings per common share, Income (Numerator)	$ 84,611us-gaap_ProfitLoss	$ 74,820us-gaap_ProfitLoss
Shares used to compute basic earnings per share	166,695	169,306
Basic earnings per common share	$ 0.51us-gaap_EarningsPerShareBasic	$ 0.44us-gaap_EarningsPerShareBasic
Dilutive effect of stock options, income	0	0
Dilutive effect of stock options, shares	4,008	4,522
Diluted earnings per common share, Income (Numerator)	$ 84,611	$ 74,820
Shares used to compute diluted earnings per share	170,703	173,828
Diluted earnings per common share	$ 0.50us-gaap_EarningsPerShareDiluted	$ 0.43us-gaap_EarningsPerShareDiluted

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of stock options or restrictive stock units (RSUs).

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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