Date the debt agreement requires a change in payment type from interest only to principal and interest.

No definition available.

Name:	irt_DebtInstrumentDateOfFirstPrincipalAndInterestPayment
Namespace Prefix:	irt_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Debt number of days of LIBOR against interest rate basis.

No definition available.

Name:	irt_DebtPeriodOfLIBORAgainstInterestRateBasis
Namespace Prefix:	irt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Fixed Interest Rate Bearing On Minimum Percentage Of Aggregate Outstanding Debt

No definition available.

Name:	irt_FixedInterestRateBearingOnMinimumPercentageOfAggregateOutstandingDebt
Namespace Prefix:	irt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Frequency of periodic payment for mortgage loans on real.

No definition available.

Name:	irt_FrequencyOfPeriodicPaymentForMortgageLoansOnRealEstate
Namespace Prefix:	irt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The 30-day LIBOR rate as of period end used for floating rate instruments.

No definition available.

Mortgage loans on real estate period of amortization schedule.

No definition available.

Name:	irt_MortgageLoansOnRealEstatePeriodOfAmortizationSchedule
Namespace Prefix:	irt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

Summary of Information Concerning Indebtedness that Encumbered our Properties (Parenthetical) (Detail)	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended		0 Months Ended	9 Months Ended		12 Months Ended	9 Months Ended
	Sep. 30, 2014 Belle Creek Apartments	Dec. 31, 2013 Belle Creek Apartments	Sep. 30, 2014 Tresa At Arrowhead	Dec. 31, 2013 Tresa At Arrowhead	Sep. 30, 2014 Centrepoint Apartments	Sep. 30, 2014 Berkshire Square Apartments	Mar. 31, 2014 King's Landing	Sep. 30, 2014 King's Landing	Sep. 30, 2014 Secured Credit Facility	Dec. 31, 2013 Secured Credit Facility	Sep. 30, 2014 OKC Portfolio
Mortgage Loans on Real Estate [Line Items]
Floating rate	2.25%	2.25%	2.25%	2.25%					2.50%	2.75%
30-day LIBOR rate	0.15%	0.17%	0.15%	0.17%					0.15%	0.17%
Debt number of days of LIBOR against interest rate basis	30 days	30 days	30 days	30 days					30 days	30 days
Interest payment period					Monthly	Monthly	Monthly	Monthly
Principal date					Feb. 01, 2015	Feb. 01, 2016	Jun. 01, 2017	Jun. 01, 2017
Amortization schedule					30 years	30 years	30 years	30 years			30 years
Contractual interest rate											5.60%