Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity (Details)

v3.19.1
Shareholders' Equity (Details)
3 Months Ended
Mar. 31, 2019
USD ($)
$ / shares
shares
Mar. 31, 2018
USD ($)
$ / shares
shares
May 04, 2018
USD ($)
agreements
Class of Stock [Line Items]      
Number of separate equity distribution agreements | agreements     8
Shares issued under dividend reinvestment program (in shares) | shares 42,842 37,079  
Shares issued under dividend reinvestment program, weighted share price per share | $ / shares $ 25.84 $ 28.16  
Value of shares issued under dividend reinvestment program $ 1,097,000 $ 717,000  
Common Stock [Member]      
Class of Stock [Line Items]      
Capital shares reserved for future issuances     $ 250,000,000.0
Common shares issued | shares 0 0  
Shares issued, average price per share | $ / shares   $ 0.00  
Shares issued under dividend reinvestment program (in shares) | shares 43,000 37,000  
Value of shares issued under dividend reinvestment program $ 0 $ 0  
Additional Paid-in Capital [Member]      
Class of Stock [Line Items]      
Proceeds from issuance of common shares   0  
Value of shares issued under dividend reinvestment program $ 1,097,000 $ 717,000