Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Investment securities held-to-maturity, fair value	$ 163,723	$ 166,582
Common Stock, Par Value	$ 1.00	$ 1.00
Common Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Shares, Issued	8,462,431	8,459,918
Common Stock, Shares, Outstanding	8,462,431	8,459,918

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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-Topic 505
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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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