Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) shares in Thousands, $ / shares in Thousands, $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt securities held to maturity, fair value	$ 920,603	$ 971,445
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	150,000	150,000
Common stock, issued (in shares)	26,901	26,730
Common stock, outstanding (in shares)	26,901	26,730

Face amount per share of no-par value 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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