| Document and Entity Information | Feb. 22, 2021 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Feb. 22, 2021 |
| Entity Registrant Name | Life Storage, Inc. |
| Entity Incorporation, State or Country Code | MD |
| Entity File Number | 001-13820 |
| Entity Tax Identification Number | 16-1194043 |
| Entity Address, Address Line One | 6467 Main Street |
| Entity Address, City or Town | Williamsville |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 14221 |
| City Area Code | 716 |
| Local Phone Number | 633-1850 |
| Entity Information, Former Legal or Registered Name | Not Applicable |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000944314 |
| Title of 12(b) Security | Common Stock, $.01 par value |
| Trading Symbol | LSI |
| Security Exchange Name | NYSE |
| LIFE STORAGE LP [Member] | |
| Entity Information [Line Items] | |
| Entity Registrant Name | Life Storage LP |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 000-24071 |
| Entity Tax Identification Number | 16-1481551 |
