Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets [Abstract]
Securities available for sale, amortized cost	$ 4,508,807	$ 1,445,721
Property and equipment, accumulated depreciation	$ 139,262	$ 125,383
Common stock, par value per share	$ 3.33	$ 3.33
Common stock, shares authorized	350,000,000	350,000,000
Common stock, shares issued	84,698,246	36,893,276
Common stock, shares outstanding	84,698,246	36,893,276

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Shares outstanding equals shares issued minus shares held in treasury and other adjustments, if any.

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