Quarterly report pursuant to Section 13 or 15(d)

Equity (Details)

v3.10.0.1
Equity (Details) - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Class of Stock [Line Items]    
Conversion of common units to common shares (in units/shares) 53,817 187,000
Forward Equity Sale Agreement    
Class of Stock [Line Items]    
Proceeds from common shares issued under forward equity sale agreements $ 52.3  
Forward Equity Sale Agreement | Common Shares    
Class of Stock [Line Items]    
Number of shares issued 1,800,000  
Remaining capacity under forward equity sale agreements 5,700,000  
Common Stock Issued to Public Under At-the-Market Program | Common Shares    
Class of Stock [Line Items]    
At-market stock, offering program established, remaining capacity $ 70.0