Earnings Per Share - Two class method (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share
Net Income	$ 7,104	$ 7,370	$ 21,888	$ 19,833
Dividends and undistributed earnings allocated to participating securities	154		514
Net income available to common shareholders	$ 6,950		$ 21,374
Weighted-average common shares outstanding for basic earnings per share	14,274	13,777	13,957	13,759
Dilutive effect of stock-based awards	352	294	360	301
Weighted-average common shares outstanding for diluted earnings per share	14,626	14,071	14,317	14,060
Earnings per common share:
Basic earnings per common share	$ 0.49	$ 0.53	$ 1.53	$ 1.44
Diluted earnings per common share	$ 0.48	$ 0.52	$ 1.49	$ 1.41

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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