Quarterly report pursuant to Section 13 or 15(d)

Equity and Mezzanine Equity - Additional Information (Details)

v3.19.1
Equity and Mezzanine Equity - Additional Information (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2019
USD ($)
$ / shares
shares
Mar. 31, 2018
USD ($)
shares
Dec. 31, 2018
USD ($)
director
quarter
$ / shares
shares
Jun. 28, 2018
$ / shares
Jun. 15, 2016
shares
Jun. 04, 2015
shares
Apr. 29, 2014
$ / shares
shares
Equity [Line Items]              
Convertible Preferred Stock, Terms of Conversion P20D            
Preferred Stock, Redemption Price Per Share | $ / shares $ 25.00            
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period 0 0          
Series D Preferred              
Equity [Line Items]              
Preferred stock, shares outstanding (in shares) 3,600,636   3,600,636        
Accretion of Preferred Stock discount | $ $ 148,000 $ 148,000          
Series A Preferred              
Equity [Line Items]              
Preferred stock, shares outstanding (in shares) 562   562        
Preferred stock, liquidation price per share (in dollars per share) | $ / shares $ 1,000   $ 1,000        
Preferred Stock, Liquidation Preference, Value | $ $ 562,000   $ 562,000        
Preferred stock shares issued (in shares) 562   562        
Preferred stock, shares authorized (in shares) 4,500   4,500        
Series B Convertible Preferred Stock              
Equity [Line Items]              
Preferred stock, liquidation price per share (in dollars per share) | $ / shares $ 25.00            
Preferred Stock, Liquidation Preference, Value | $ $ 46,900,000.00            
Preferred Stock, Dividend Rate, Percentage 9.00%            
Preferred stock shares issued (in shares) 1,875,748            
Preferred stock, shares authorized (in shares) 5,000,000            
Preferred Stock Adjusted Conversion Price Per Share | $ / shares $ 58            
Preferred Stock, Redemption Price Per Share | $ / shares $ 40.00            
Series D Preferred Stock              
Equity [Line Items]              
Preferred stock, shares outstanding (in shares) 3,600,636            
Preferred stock, liquidation price per share (in dollars per share) | $ / shares $ 25.00   $ 25.00 $ 25.00      
Preferred Stock, Liquidation Preference Per Share Per Annum | $ / shares     $ 0.50        
Preferred Stock, Liquidation Preference, Value | $ $ 94,400,000.00   $ 91,980,000.00        
Preferred Stock, Dividend Rate, Percentage 10.75%   8.75%        
Preferred stock shares issued (in shares) 3,600,636            
Preferred stock, shares authorized (in shares) 4,000,000            
Preferred Stock, Minimum Consecutive Quarterly Periods for Dividends in Arrears | quarter     6        
Preferred Stock, Initial Liquidation Preference Per Share | $ / shares $ 2.1875            
Preferred Stock, Dividend Over Initial Rate, Percentage 2.00%   2.00%        
Convertible Preferred Stock Conversion Price | $ / shares $ 16.96            
Preferred Stock, Percentage of Holders of Shares Outstanding     20.00%        
Number of Additional Directors | director     2        
Redeemable Preferred Stock              
Equity [Line Items]              
Preferred stock, shares outstanding (in shares) 562            
Common Stock              
Equity [Line Items]              
Class of Warrant or Right, Number of Securities Called by Warrants or Rights             1,986,600
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right             0.125
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares             $ 44
Common Stock | 2015 Share Incentive Plan              
Equity [Line Items]              
Maximum number of shares authorized under Share Incentive Plan (in shares)           125,000  
Shares available for issuance under Share Incentive Plan (in shares) 41,104            
Common Stock | 2016 Share Incentive Plan              
Equity [Line Items]              
Maximum number of shares authorized under Share Incentive Plan (in shares)         625,000    
Shares available for issuance under Share Incentive Plan (in shares) 132,707            
Maximum | Series D Preferred Stock              
Equity [Line Items]              
Preferred Stock, Dividend Rate, Percentage 14.00%            
Equity Distribution Agreement | Series A Preferred | Preferred Stock              
Equity [Line Items]              
Preferred Stock, Dividend Rate, Percentage 9.00%            
Conversion Price Percentage 103.00%