Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Details)

v3.19.1
Stockholders' Equity (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 1 Months Ended 12 Months Ended
Jul. 11, 2016
Dec. 31, 2018
Aug. 17, 2018
Sep. 30, 2017
Jun. 30, 2017
Jul. 31, 2016
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 14, 2018
Sep. 30, 2018
Sep. 15, 2017
Jul. 01, 2016
Preferred Stock, Shares Authorized   10,000         10,000 10,000          
Preferred Stock, Par or Stated Value Per Share   $ 0.001         $ 0.001 $ 0.001          
Preferred Stock, Shares Issued   3,105         3,105 3,105          
Common Stock, Shares Authorized   500,000         500,000 500,000          
Common Stock, Par or Stated Value Per Share   $ 0.001         $ 0.001 $ 0.001          
Common Stock, Shares, Outstanding   25,944         25,944 21,631          
Dividends Payable   $ 6,981         $ 6,981 $ 5,638          
Preferred Stock, Liquidation Preference Per Share   $ 25         $ 25            
Payments of Ordinary Dividends, Preferred Stock and Preference Stock             $ 5,821 $ 745          
Limited Partners' Capital Account, Units Issued   1,899         1,899 1,246          
Payments of dividens, Common Stock, OP and LTIP Units             $ (18,964) $ (15,231) $ (3,878)        
Partners' Capital Account, Units, Sale of Units             3,145 1,246          
Limited Partners' Capital Account   $ 27,894         $ 27,894 $ 11,532          
Proceeds from Issuance of Common Stock             37,307 33,795 137,288        
Stock To Be Issued During Period Value ATM Offering     $ 50,000                    
Stock Issued During Period, Shares, New Issues 15,000                        
Stock Issued During Period, Value, New Issues                 138,969        
Preferred Stock, Value, Issued   74,959         74,959 74,959          
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs   174     $ 1,987       1,681        
Proceeds from Issuance Initial Public Offering $ 138,969                        
Reclassification Of Common Stock Offering Cost To Additional Paid In Capital Non Cash Or Partial Non Cash Transaction 1,681           $ 573 443 1,681        
BeneficialOwnershipDescription             The Company’s charter provides that, subject to certain exceptions, no person may beneficially or constructively own more than 9.8%, in value or in number of shares, whichever is more restrictive, of the outstanding shares of any class or series of the Company’s capital stock. On June 27, 2016, the Board approved a waiver of the 9.8% ownership limit in the Company’s charter allowing ZH USA, LLC to own up to 16.9% of the Company’s outstanding shares of common stock.            
Payments of Dividends, Total             $ 5,821 745 $ 0        
Noncontrolling Interest, Increase from Subsidiary Equity Issuance             16,363 11,532          
At The Market [Member]                          
Proceeds from Issuance of Common Stock     $ 5,767                    
Commission On Sale Of Stock             $ 122            
Stock Issued During Period, Shares, New Issues             662            
Stock Issued During Period, Value, New Issues             $ 6,235            
Payments of Stock Issuance Costs             346            
Shares Issued, Price Per Share     $ 9.41                    
Common Stock [Member]                          
Dividends Payable   245         245 117          
Proceeds from Issuance of Common Stock   $ 31,540     $ 33,795                
Stock Issued During Period, Shares, New Issues   3,651     4,025       15,000        
Stock Issued During Period, Value, New Issues   $ 32,863     $ 36,225       $ 15        
Shares Issued, Price Per Share         $ 9.00         $ 9.00      
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs         $ 443       $ 0        
Restructuring and Related Cost, Incurred Cost   53                      
Payments of Dividends, Total             46            
Noncontrolling Interest, Increase from Subsidiary Equity Issuance             0          
Common Stock [Member] | Over-Allotment Option [Member]                          
Proceeds from Issuance of Common Stock $ 18,195                        
Stock Issued During Period, Shares, New Issues 1,957                        
Stock Issued During Period, Value, New Issues $ 19,565                        
Shares Issued, Price Per Share $ 10.00                        
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs   $ 1,149                      
Common Stock [Member] | IPO [Member]                          
Proceeds from Issuance of Common Stock $ 137,288                        
Stock Issued During Period, Shares, New Issues           13,043              
Stock Issued During Period, Value, New Issues           $ 130,435              
Shares Issued, Price Per Share                         $ 10.00
Proceeds from Issuance Initial Public Offering           $ 120,774              
Series A Preferred Stock [Member]                          
Preferred Stock, Par or Stated Value Per Share                       $ 0.001  
Preferred Stock, Shares Issued   3,105         3,105            
Common Stock, Shares, Outstanding   3,105         3,105            
Dividends Payable, Amount Per Share                     $ 1.875    
Preferred Stock, Liquidation Preference Per Share                       25  
Preferred Stock, Dividend Rate, Percentage             7.50%            
Stock Issued During Period, Shares, New Issues       3,105                  
Stock Issued During Period, Value, New Issues       $ 77,625                  
Payments of Stock Issuance Costs       $ 221                  
Preferred Stock, Redemption Price Per Share                       $ 25  
Series A Preferred Stock [Member] | Over-Allotment Option [Member]                          
Stock Issued During Period, Shares, New Issues       405                  
Payments of Stock Issuance Costs       $ 2,445                  
Long Tem Incentives Plan Units [Member]                          
Dividends Payable   $ 316         $ 316 $ 117          
Dividend Reinvestment and stock Purchase Plan units [Member]                          
Common Stock, Shares Authorized   1,000         1,000