Organization - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2019 Property State shares	Dec. 31, 2018 shares
Organization [Line Items]
Number of self-storage properties owned and managed	794
Number of states in which self-storage properties owned and managed | State	28
Number of properties managed under joint ventures	114
Number of properties managed with no ownership	113
Noncontrolling limited partnership unit redemption value	one common share or cash
Geographic Concentration Risk [Member] | Texas [Member] | Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	20.00%
Geographic Concentration Risk [Member] | Florida [Member] | Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	12.00%
Life Storage LP [Member]
Organization [Line Items]
Units of redeemable noncontrolling interest in operating partnership | shares	248,466	248,966
Life Storage LP [Member]
Organization [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership	99.50%
Warehouse Anywhere LLC [Member] | Life Storage Solutions, LLC [Member]
Organization [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership	60.00%