CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
CONSOLIDATED BALANCE SHEETS
Available-for-sale investment securities, amortized cost	$ 3,427,708	$ 3,549,599
Held-to-maturity investment securities, fair value	$ 3,824,478	$ 3,814,822
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	300,000,000	300,000,000
Common stock, issued (in shares)	141,291,086	140,963,918
Common stock outstanding (in shares)	127,573,680	127,363,327
Treasury stock (in shares)	13,717,406	13,600,591

Face amount or stated value per share of common stock.

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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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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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