Numerator and Denominator of the Basic and Diluted Per Share Computations for Earnings Attributable to Shareholders Per Share (Detail) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net Earnings Attributable to Shareholders
Basic earnings attributable to shareholders	$ 95,000	$ 90,318	$ 186,232	$ 151,565
Diluted earnings attributable to shareholders	$ 95,000	$ 90,318	$ 186,232	$ 151,565
Weighted Average Shares
Weighted average basic shares outstanding	212,136,164	212,332,375	212,112,643	212,262,928
Effect of dilutive potential common shares	3,522,879	4,128,602	3,667,587	4,313,668
Weighted average diluted shares outstanding	215,659,043	216,460,977	215,780,230	216,576,596
Earnings Per Share
Basic earnings attributable to shareholders per share	$ 0.45	$ 0.43	$ 0.88	$ 0.71
Diluted earnings attributable to shareholders per share	$ 0.44	$ 0.42	$ 0.86	$ 0.70

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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 after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the 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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