Common Stock (Narrative) (Details) $ / shares in Units, $ in Thousands				3 Months Ended
	Mar. 29, 2017 USD ($) $ / shares shares	Mar. 15, 2017 USD ($) shares	Feb. 28, 2017 $ / shares shares	Mar. 31, 2017 USD ($) shares
Class of Stock [Line Items]
Shares issued, price per share | $ / shares	$ 10.50
Reverse stock split, conversion ratio		0.1538
Reverse stock split, fractional shares issued		0
Reverse stock split, shares settled in cash		73
Reverse stock split, shares settled in cash, amount | $		$ 1		$ 1
Issuance of common stock, shares	4,772,500
Proceeds from common stock issued | $	$ 45,916			$ 45,916
Pursuant To Full Exercise Of An Option To Purchase Additional Shares Of Common Stock Granted To Underwriters [Member]
Class of Stock [Line Items]
Issuance of common stock, shares	622,500
Common Stock [Member]
Class of Stock [Line Items]
Shares issued upon conversion			6,004,957
Shares issued, price per share | $ / shares			$ 10.40
Issuance of common stock, shares				4,772,000