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Net Income (Loss) Per Common Share (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Jun. 05, 2018	Jun. 01, 2018	May 25, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Proceeds from issuance of common stock net of underwriting discount and other offering fees and expenses					$ 32,246
Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount				593,975	323,250	590,350
Weighted average price of anti-dilutive options outstanding				$ 26.91	$ 32.36	$ 30.63
Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount						268,351
Underwritten Public Offering [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Gross proceeds from issuance of common stock		$ 34,500
Proceeds from issuance of common stock net of underwriting discount and other offering fees and expenses		$ 32,200
Public offering's impact on weighted average number of shares					800,000
Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Public offering (Shares)					1,408,163
Common Stock [Member] \| Underwritten Public Offering [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Public offering (Shares)	183,673		1,224,490
Shares issued price per share			$ 24.50
Underwriters purchase option period			30 days