Partners' Capital - Reconciliation of Change in Total Partners' Capital (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Partners Capital [Line Items]
Exercise of stock options		$ 173
Earned portion of non-vested stock	$ 1,743	1,661	$ 1,467	$ 1,453
Carrying value less than redemption value on redeemed noncontrolling interest	(2)		(13)	(4)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	(27,930)	(10,924)	7,142	2,358
Net income attributable to common shareholders/unitholders	92,264	73,575	57,516	47,383	$ 165,839	$ 104,898
Amortization of terminated hedge included in AOCL	229	229	229	229
Life Storage LP [Member]
Partners Capital [Line Items]
Beginning balance of total controlling partners’ capital	3,474,695	3,378,999	2,549,490	2,378,098	3,378,999	2,378,098
Net proceeds from issuance of Operating Partnership Units	7,865	92,771	148,325	180,529
Exercise of stock options		173
Earned portion of non-vested stock	1,743	1,661	1,467	1,453
Issuance of common Operating Partnership Units	0
Carrying value less than redemption value on redeemed noncontrolling interest	(2)	0	(13)	(4)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	27,930	10,924	(7,142)	(2,358)
Net income attributable to common shareholders/unitholders	92,264	73,575	57,516	47,383	165,839	104,898
Amortization of terminated hedge included in AOCL	229	229	229	229
Distributions	(84,363)	(83,637)	(56,873)	(55,840)
Ending balance of total controlling partners’ capital	3,520,361	3,474,695	2,692,999	2,549,490	3,520,361	2,692,999
Life Storage LP [Member] | Life Storage Holdings, Inc. General Partner [Member]
Partners Capital [Line Items]
Beginning balance of total controlling partners’ capital	36,986	36,131	25,782	24,045	36,131	24,045
Net proceeds from issuance of Operating Partnership Units	80	927	1,483	1,807
Exercise of stock options		2
Earned portion of non-vested stock	17	17	15	14
Issuance of common Operating Partnership Units	103
Carrying value less than redemption value on redeemed noncontrolling interest	(2)	(1)	(1)	(1)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	0	0	0	0
Net income attributable to common shareholders/unitholders	944	754	578	476
Amortization of terminated hedge included in AOCL	2	2	2	2
Distributions	(853)	(846)	(572)	(561)
Ending balance of total controlling partners’ capital	37,277	36,986	27,287	25,782	37,277	27,287
Life Storage LP [Member] | Life Storage, Inc. Limited Partner [Member]
Partners Capital [Line Items]
Beginning balance of total controlling partners’ capital	3,441,604	3,346,992	2,528,520	2,359,094	3,346,992	2,359,094
Net proceeds from issuance of Operating Partnership Units	7,785	91,844	146,842	178,722
Exercise of stock options		171
Earned portion of non-vested stock	1,726	1,644	1,452	1,439
Issuance of common Operating Partnership Units	(103)
Carrying value less than redemption value on redeemed noncontrolling interest	0	1	(12)	(3)
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	27,930	10,924	(7,142)	(2,358)
Net income attributable to common shareholders/unitholders	91,320	72,821	56,938	46,907
Amortization of terminated hedge included in AOCL	(2)	(2)	(2)	(2)
Distributions	(83,510)	(82,791)	(56,301)	(55,279)
Ending balance of total controlling partners’ capital	3,486,750	3,441,604	2,670,295	2,528,520	3,486,750	2,670,295
Accumulated Other Comprehensive Income (Loss) [Member]
Partners Capital [Line Items]
Exercise of stock options		0
Earned portion of non-vested stock	0	0	0	0
Carrying value less than redemption value on redeemed noncontrolling interest	0		0	0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	0	0	0	0
Net income attributable to common shareholders/unitholders	0	0	0	0
Amortization of terminated hedge included in AOCL	229	229	229	229
Accumulated Other Comprehensive Income (Loss) [Member] | Life Storage LP [Member]
Partners Capital [Line Items]
Beginning balance of total controlling partners’ capital	(3,895)	(4,124)	(4,812)	(5,041)	(4,124)	(5,041)
Net proceeds from issuance of Operating Partnership Units	0	0	0	0
Exercise of stock options		0
Earned portion of non-vested stock	0	0	0	0
Issuance of common Operating Partnership Units	0
Carrying value less than redemption value on redeemed noncontrolling interest	0	0	0	0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units	0	0	0	0
Net income attributable to common shareholders/unitholders	0	0	0	0
Amortization of terminated hedge included in AOCL	229	229	229	229
Distributions	0	0	0	0
Ending balance of total controlling partners’ capital	$ (3,666)	$ (3,895)	$ (4,583)	$ (4,812)	$ (3,666)	$ (4,583)