| Cover | Aug. 26, 2021 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 26, 2021 |
| Entity File Number | 001-36109 |
| Entity Registrant Name | QTS Realty Trust, Inc. |
| Entity Central Index Key | 0001577368 |
| Entity Tax Identification Number | 46-2809094 |
| Entity Incorporation, State or Country Code | MD |
| Entity Address, Address Line One | 12851 Foster Street |
| Entity Address, City or Town | Overland Park |
| Entity Address, State or Province | KS |
| Entity Address, Postal Zip Code | 66213 |
| City Area Code | 913 |
| Local Phone Number | 814-9988 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Class A common stock, $0.01 par value |
| Trading Symbol | QTS |
| Security Exchange Name | NYSE |
| Series A Preferred Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Preferred Stock, 7.125% Series A Cumulative Redeemable Perpetual, $0.01 par value |
| Trading Symbol | QTS PR A |
| Security Exchange Name | NYSE |
| Series B Preferred Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Preferred Stock, 6.50% Series B Cumulative Convertible Perpetual, $0.01 par value |
| Trading Symbol | QTS PR B |
| Security Exchange Name | NYSE |
