Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Assets
Securities held to maturity, fair value	$ 76,007	$ 145,143
Shareholders' Equity
Common stock, authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	64,119,235	63,917,591
Common stock, shares outstanding (in shares)	64,119,235	63,917,591

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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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This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

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