Earnings per Share ("EPS") ( Earnings per Share Basic and Diluted) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Schedule Of Computation Of Basic And Diluted Earnings Per Common Share [Line Items]
Net Income Applicable To Common Shareholders	$ 42,399	$ 23,473
Average Common Shares Outstanding	186,607	171,326
Basic Earnings Per Common Share	$ 0.23	$ 0.14
Net Income Available To Common Shareholders	$ 42,399	$ 23,473
Average Common Shares Outstanding	186,607	171,326
Dilutive Potential Common Shares	835	647
Total Diluted Average Common Shares Outstanding	187,442	171,973
Diluted Earnings Per Common Share	$ 0.23	$ 0.14
Antidilutive Potential Common Stock Equivalents/Options	1,586	1,991

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Options issued under share-based compensation arrangements that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

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Weighted average number of basic shares outstanding.

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- Definition

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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- Definition

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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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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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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