Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2017	Feb. 23, 2018	Jun. 30, 2017
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Entity Registrant Name	QTS Realty Trust, Inc.
Entity Central Index Key	0001577368
Entity Filer Category	Large Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Current Fiscal Year End Date	--12-31
Entity Public Float			$ 2.6
Class A Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		50,597,741
Class B Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		128,408
Qualitytech, LP
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Entity Registrant Name	QualityTech, LP
Entity Central Index Key	0001561164
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Current Fiscal Year End Date	--12-31