Consolidated Balance Sheets (Parentheticals) - $ / shares shares in Thousands	Dec. 31, 2018	Dec. 31, 2017
Common Stock, Number of Shares, Par Value and Other Disclosures
Common stock, par value (in dollars per share)
Common stock, shares authorized (in shares)	75,000	75,000
Common stock, shares issued (in shares)	39,498	38,771
Common stock, shares outstanding (in shares)	39,498	38,771
Preferred Stock, Number of Shares, Par Value and Other Disclosures
Preferred stock, par value (in dollars per share)
Preferred stock, shares authorized (in shares)	10,000	10,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Face amount per share of no-par value common stock.

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