Annual report pursuant to Section 13 and 15(d)

EARNINGS PER SHARE - Basic and Diluted Earnings per Share (Details)

v3.10.0.1
EARNINGS PER SHARE - Basic and Diluted Earnings per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Numerator                      
Net income $ 14,483 $ 16,829 $ 13,041 $ 11,973 $ 12,015 $ 11,226 $ 15,576 $ 7,181 $ 56,326 $ 45,998 $ 24,866
Net income attributable to noncontrolling interests                 (42,217) (43,037) (6,901)
Net income attributable to National Storage Affiliates Trust                 14,109 2,961 17,965
Distributions to preferred shareholders                 (10,350) (2,300) 0
Distributed and undistributed earnings allocated to participating securities                 (27) (28) (18)
Net income attributable to common shareholders - basic                 3,732 633 17,947
Effect of assumed conversion of dilutive securities                 0 0 6,783
Net income attributable to common shareholders - diluted                 $ 3,732 $ 633 $ 24,730
Denominator                      
Weighted average shares outstanding - basic (in shares)                 53,293 44,423 29,887
Weighted average shares outstanding - diluted (in shares)                 53,293 44,423 78,747
Earnings (loss) per share - basic (in dollars per share) $ (0.16) $ 0.03 $ 0.07 $ 0.16 $ (0.08) $ 0.03 $ 0.05 $ 0.01 $ 0.07 $ 0.01 $ 0.60
Earnings (loss) per share - diluted (in dollars per share) $ (0.16) $ 0.03 $ 0.07 $ 0.09 $ (0.08) $ 0.03 $ 0.05 $ 0.01 0.07 0.01 0.31
Dividends declared per common share (in dollars per share)                 $ 1.16 $ 1.04 $ 0.88
OP units [Member] | NSA OP, LP [Member]                      
Denominator                      
Effect of dilutive securities (in shares)                 0 0 24,262
OP units [Member] | DownREIT Partnership [Member]                      
Denominator                      
Effect of dilutive securities (in shares)                 0 0 1,835
LTIP units [Member] | NSA OP, LP [Member]                      
Denominator                      
Effect of dilutive securities (in shares)                 0 0 1,846
Subordinated performance units [Member] | NSA OP, LP And DownREIT Partnership [Member]                      
Denominator                      
Effect of dilutive securities (in shares)                 0 0 20,917