EPS - Computations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Operations:
Net income	$ 8,215	$ 7,911	$ 9,720	$ 9,008	$ 7,527	$ 8,927	$ 25,846	$ 25,462
Less: Income attributable to participating securities	54			174			171	491
Net income attributable to common shareholders and used in earnings per share calculation	$ 8,161			$ 8,834			$ 25,675	$ 24,971
Share information:
Basic and diluted weighted average common shares (in shares)	17,027,068			16,872,091			17,006,226	16,861,700
Basic and diluted EPS (in dollars per share)	$ 0.48			$ 0.52			$ 1.51	$ 1.48

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or 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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Amount of undistributed earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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