Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Debt securities held to maturity, fair value	$ 301,595	$ 287,904
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock authorized (in shares)	150,000,000	150,000,000
Common stock issued (in shares)	78,283,544	79,013,729
Common stock outstanding (in shares)	78,283,544	79,013,729
Common stock issuable (in shares)	591,053	664,640

Represents number of shares of common stock issuable.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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- Definition

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

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-Publisher FASB
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