Summary of Significant Accounting Policies - Schedule of Basic and Diluted Net Income (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator
Numerator for basic and diluted earnings per share-net income	$ 8,973	$ 2,616
Denominator
Basic weighted average common shares outstanding (in shares)	13,925,227	14,819,530
Dilutive effect of stock options (in shares)	492,984	658,805
Diluted weighted average common shares outstanding (in shares)	14,418,211	15,478,335
Basic net income per share
Basic net income per share (in usd per share)	$ 0.64	$ 0.18
Diluted net income per share
Diluted net income per share (in usd per share)	$ 0.62	$ 0.17

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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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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