Partners' Capital, Equity and Incentive Compensation Plans (Summary of Assumptions and Fair Values for Restricted Stock and Options to Purchase Shares of Class A Common Stock Granted) (Details)	9 Months Ended
Sep. 30, 2019 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of TSR units granted	54.64
Expected term (years)	5 years 6 months
Expected volatility	28.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of FFO units and restricted stock granted	42.01
Fair value of restricted stock granted	$ 7.56
Expected dividend yield	3.89%
Expected risk-free interest rates	2.33%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of FFO units and restricted stock granted	45.58
Fair value of restricted stock granted	$ 8.28
Expected dividend yield	4.19%
Expected risk-free interest rates	2.56%

Fair Value Per Share Of Funds From Operations And Restricted Stock Units Granted

No definition available.

Name:	qts_FairValuePerShareOfFundsFromOperationsAndRestrictedStockUnitsGranted
Namespace Prefix:	qts_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair Value Per Share Of Restricted Stock Units Granted

+ References

No definition available.

+ Details

Name:	qts_FairValuePerShareOfRestrictedStockUnitsGranted
Namespace Prefix:	qts_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value per share of Total Shareholders Return awards granted

+ References

No definition available.

+ Details

Name:	qts_FairValuePerShareOfTotalShareholdersReturnAwardsGranted
Namespace Prefix:	qts_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: