Consolidated Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Amortized Cost	$ 973,923	$ 1,028,883
Securities held-to-maturity, fair value	$ 364,560	$ 351,422
Preferred Stock, Shares Authorized	200,000	200,000
Preferred Stock, Shares Issued	0	0
Common stock no par value	$ 0	$ 0
Common stock shares authorized	20,000,000	20,000,000
Common Stock, Shares, Issued	17,623,216	16,586,165
Treasury stock shares	1,205,654	887,987

Amortized cost 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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