| Document and Entity Information Document | Jun. 03, 2020 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jun. 3, 2020 |
| Entity Registrant Name | LEXINGTON REALTY TRUST |
| Entity Central Index Key | 0000910108 |
| Document Fiscal Year Focus | 2020 |
| Document Fiscal Period Focus | Q2 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | MD |
| Entity File Number | 001-2386 |
| Entity Tax Identification Number | 13-3717318 |
| Entity Address, Address Line One | One Penn Plaza, Suite 4015, |
| Entity Address, City or Town | New York, |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10119-4015 |
| City Area Code | 212 |
| Local Phone Number | 692-7200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| NEW YORK STOCK EXCHANGE, INC. [Member] | Common Class A [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Shares of beneficial interest, par value $0.0001 per share, classified as Common Stock |
| Trading Symbol | LXP |
| Security Exchange Name | NYSE |
| NEW YORK STOCK EXCHANGE, INC. [Member] | Series C Preferred Stock [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | 6.50% Series C Cumulative Convertible Preferred Stock, par value $0.0001 per share |
| Trading Symbol | LXPPRC |
| Security Exchange Name | NYSE |
