Annual report pursuant to Section 13 and 15(d)

Supplementary Quarterly Financial Data (Unaudited) - Summary of Quarterly Results of Operations (Detail)

v3.8.0.1
Supplementary Quarterly Financial Data (Unaudited) - Summary of Quarterly Results of Operations (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Quarterly Financial Information [Line Items]                      
Operating revenue $ 133,078 $ 135,568 $ 132,784 $ 128,320 $ 128,678 $ 127,801 $ 107,005 $ 99,124 $ 529,750 $ 462,608 $ 366,602
Net income (loss) 21,185 35,667 19,432 20,525 18,191 (4,969) 43,504 28,230 96,809 84,956 113,077
Net income (loss) attributable to common shareholders/unitholders $ 21,085 $ 35,496 $ 19,355 $ 20,429 $ 18,168 $ (4,738) $ 43,456 $ 28,339 $ 96,365 $ 85,225 $ 112,524
Earnings per common share/unit attributable to common shareholders/unitholders - basic $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 0.39 $ (0.10) $ 1.04 $ 0.74 $ 2.08 $ 1.97 $ 3.18
Earnings per common share/unit attributable to common shareholders/unitholders - diluted $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 0.39 $ (0.10) $ 1.03 $ 0.73 $ 2.07 $ 1.96 $ 3.16
Life Storage LP [Member]                      
Quarterly Financial Information [Line Items]                      
Operating revenue $ 133,078 $ 135,568 $ 132,784 $ 128,320 $ 128,678 $ 127,801 $ 107,005 $ 99,124 $ 529,750 $ 462,608 $ 366,602
Net income (loss) 21,185 35,667 19,432 20,525 18,191 (4,969) 43,504 28,230 96,809 84,956 113,077
Net income (loss) attributable to common shareholders/unitholders $ 21,085 $ 35,496 $ 19,355 $ 20,429 $ 18,168 $ (4,738) $ 43,456 $ 28,339 $ 96,365 $ 85,225 $ 112,524
Earnings per common share/unit attributable to common shareholders/unitholders - basic $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 0.39 $ (0.10) $ 1.04 $ 0.74 $ 2.08 $ 1.97 $ 3.18
Earnings per common share/unit attributable to common shareholders/unitholders - diluted $ 0.45 $ 0.76 $ 0.42 $ 0.44 $ 0.39 $ (0.10) $ 1.03 $ 0.73 $ 2.07 $ 1.96 $ 3.16