Annual report pursuant to Section 13 and 15(d)

Earnings Per Share and Earnings Per Unit - Computation of Basic and Diluted Earnings Per Common Share/Unit (Detail)

v3.10.0.1
Earnings Per Share and Earnings Per Unit - Computation of Basic and Diluted Earnings Per Common Share/Unit (Detail) - 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 attributable to common shareholders/unitholders $ 92,307 $ 41,120 $ 39,274 $ 33,889 $ 21,085 $ 35,496 $ 19,355 $ 20,429 $ 206,590 $ 96,365 $ 85,225
Denominator:                      
Denominator for basic earnings per share/unit - weighted average shares/units                 46,501 46,373 43,184
Effect of Dilutive Securities:                      
Stock options and non-vested stock                 96 117 223
Denominator for diluted earnings per share/unit - adjusted weighted average shares/units and assumed conversion                 46,597 46,490 43,407
Basic Earnings per common share/unit attributable to common shareholders/unitholders $ 1.98 $ 0.88 $ 0.84 $ 0.73 $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 4.44 $ 2.08 $ 1.97
Diluted Earnings per common share/unit attributable to common shareholders/unitholders $ 1.98 $ 0.88 $ 0.84 $ 0.73 $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 4.43 $ 2.07 $ 1.96
Life Storage LP [Member]                      
Numerator:                      
Net income attributable to common shareholders/unitholders $ 92,307 $ 41,120 $ 39,274 $ 33,889 $ 21,085 $ 35,496 $ 19,355 $ 20,429 $ 206,590 $ 96,365 $ 85,225
Denominator:                      
Denominator for basic earnings per share/unit - weighted average shares/units                 46,501 46,373 43,184
Effect of Dilutive Securities:                      
Stock options and non-vested stock                 96 117 223
Denominator for diluted earnings per share/unit - adjusted weighted average shares/units and assumed conversion                 46,597 46,490 43,407
Basic Earnings per common share/unit attributable to common shareholders/unitholders $ 1.98 $ 0.88 $ 0.84 $ 0.73 $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 4.44 $ 2.08 $ 1.97
Diluted Earnings per common share/unit attributable to common shareholders/unitholders $ 1.98 $ 0.88 $ 0.84 $ 0.73 $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 4.43 $ 2.07 $ 1.96