Earnings Per Share and Earnings Per Unit - Computation of Basic and Diluted Earnings Per Common Share/Unit (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net income attributable to common shareholders/unitholders	$ 98,505	$ 92,264	$ 73,575	$ 70,274	$ 57,516	$ 47,383	$ 264,344	$ 175,172
Net income attributable to unvested restricted shares	(172)			(119)			(151)	(78)
Net income attributable to outstanding common shares	$ 98,333			$ 70,155			$ 264,193	$ 175,094
Denominator:
Denominator for basic earnings per share/unit - weighted average shares/units	84,472,979			78,961,434			84,129,261	77,135,429
Effect of Dilutive Securities:
Net income attributable to preferred units	999			0			999	0
Numerator for diluted earning per share	$ 99,332			$ 70,155			$ 265,192	$ 175,094
Stock options and non-vested stock	924,000			219,000			425,000	168,000
Denominator for diluted earnings per share/unit - adjusted weighted average shares/units and assumed conversion	85,396,539			79,179,816			84,554,165	77,303,339
Basic earnings per common share/unit attributable to common shareholders/unitholders	$ 1.16			$ 0.89			$ 3.14	$ 2.27
Diluted earnings per common share/unit attributable to common shareholders/unitholders	$ 1.16			$ 0.89			$ 3.14	$ 2.27
Life Storage LP [Member]
Numerator:
Net income attributable to common shareholders/unitholders	$ 98,505	$ 92,264	$ 73,575	$ 70,274	$ 57,516	$ 47,383	$ 264,344	$ 175,172
Net income attributable to unvested restricted shares	(172)			(119)			(151)	(78)
Net income attributable to outstanding common shares	$ 98,333			$ 70,155			$ 264,193	$ 175,094
Denominator:
Denominator for basic earnings per share/unit - weighted average shares/units	84,472,979			78,961,434			84,129,261	77,135,429
Effect of Dilutive Securities:
Net income attributable to preferred units	999			0			999	0
Numerator for diluted earning per share	$ 99,332			$ 70,155			$ 265,192	$ 175,094
Stock options and non-vested stock	924,000			219,000			425,000	168,000
Denominator for diluted earnings per share/unit - adjusted weighted average shares/units and assumed conversion	85,396,539			79,179,816			84,554,165	77,303,339
Basic earnings per common share/unit attributable to common shareholders/unitholders	$ 1.16			$ 0.89			$ 3.14	$ 2.27
Diluted earnings per common share/unit attributable to common shareholders/unitholders	$ 1.16			$ 0.89			$ 3.14	$ 2.27