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Earnings Per Share - Reconciliation (Details) - USD ($)		3 Months Ended			12 Months Ended	15 Months Ended
Earnings Per Share - Reconciliation (Details) - USD ($)	Jan. 16, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2016	Dec. 31, 2009	Mar. 31, 2019	Jan. 16, 2009
Basic earnings per share:
Weighted-average common shares outstanding		29,845,653	29,659,454
Net income		$ 8,468,000	$ 9,489,000
Basic earnings per share (in dollars per share)		$ 0.28	$ 0.32
Diluted earnings per share:
Weighted-average common shares outstanding		29,845,653	29,659,454
Diluted average common shares outstanding		30,343,631	30,168,748
Net earnings available to common stockholders		$ 8,468,000	$ 9,489,000
Diluted earnings per share (in dollars per share)		$ 0.28	$ 0.31
Warrants, exercise price (in dollars per share)	$ 14.23						$ 13.43
Warrant term				10 years
Stock warrants exercised	$ (313,000)
Stock warrants exercised (in shares)	45,836
Warrant [Member]
Diluted earnings per share:
Antidilutive securities			815,339
Warrants, exercise price (in dollars per share)							$ 13.43
Warrant term		10 years	10 years		10 years	10 years
Restricted Stock and Restricted Stock Units [Member]
Diluted earnings per share:
Dilutive effect of share-based payment awards (in shares)		497,978	472,936
Employee and Nonemployee Stock Options [Member]
Diluted earnings per share:
Dilutive effect of share-based payment awards (in shares)			36,358