Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investment securities [Abstract]
Investment securities, fair value	$ 367,298	$ 480,035
Real estate and other repossessed assets, allowance	$ 13,665	$ 12,648
Shareholders' equity: [Abstract]
Common stock, par value (in dollars per share)	$ 0.00006	$ 0.00006
Common stock, shares authorized (in shares)	2,500,000,000	2,500,000,000
Common stock, shares issued (in shares)	75,711,492	75,147,686
Common stock, shares outstanding (in shares)	75,711,492	75,147,686
Treasury stock, shares at cost (in shares)	3,588,560	9,752,749

Face amount or stated value per share of common stock.

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

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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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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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