Annual report pursuant to Section 13 and 15(d)

Consolidated Balance Sheets (Parenthetical)

v3.8.0.1
Consolidated Balance Sheets (Parenthetical) - $ / shares
Dec. 31, 2017
Dec. 31, 2016
Senior common stock, par value (in dollars per share) $ 0.001 $ 0.001
Senior common stock, shares authorized (in shares) 4,450,000 4,450,000
Senior common stock, shares issued (in shares) 904,819 959,552
Senior common stock, shares outstanding (in shares) 904,819 959,552
Common stock, par value (in dollars per share) $ 0.001 $ 0.001
Common stock, shares authorized (in shares) 34,200,000 34,040,000
Common stock, shares issued (in shares) 28,384,016 24,882,758
Common stock, shares outstanding (in shares) 28,384,016 24,882,758
Series D Preferred Stock    
Redeemable preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Redeemable preferred stock, liquidation preference (in dollars per share) $ 25 $ 25
Redeemable preferred stock, shares authorized (in shares) 6,000,000 6,000,000
Redeemable preferred stock, shares issued (in shares) 3,421,853 2,917,458
Redeemable preferred stock, shares outstanding (in shares) 3,421,853 2,917,458
Series A and B Preferred Stock    
Redeemable preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Redeemable preferred stock, liquidation preference (in dollars per share) $ 25 $ 25
Redeemable preferred stock, shares authorized (in shares) 5,350,000 5,350,000
Redeemable preferred stock, shares issued (in shares) 2,264,000 2,264,000
Redeemable preferred stock, shares outstanding (in shares) 2,264,000 2,264,000