Equity Investment Basis Adjustment, Amortization Period

No definition available.

Name:	ivtp_EquityInvestmentBasisAdjustmentAmortizationPeriod
Namespace Prefix:	ivtp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Investments in Affiliates, Subsidiaries, Associates, and Joint Ventures, Properties Contributed

+ References

No definition available.

+ Details

Name:	ivtp_InvestmentsinAffiliatesSubsidiariesAssociatesandJointVenturesPropertiesContributed
Namespace Prefix:	ivtp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of gain on the sale of property that does not qualify for gain recognition as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredGainOnSaleOfProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of investment in equity method investee and investment in and advance to affiliate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=ivtp_UnconsolidatedEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ivtp_IAGMRetailFundILLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201705Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ivtp_DowntownRailyardVentureLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ivtp_OtherUnconsolidatedEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Investment in Consolidated and Unconsolidated Entities - Schedule of Joint Ventures (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2013 USD ($) property	Dec. 31, 2018 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2015 USD ($)
Schedule of net equity investment and share of net income or loss
Investment in unconsolidated entities		$ 156,132		$ 180,764
Unconsolidated Entities
Schedule of net equity investment and share of net income or loss
Investment in unconsolidated entities		$ 156,132		180,764
Unconsolidated Entities \| IAGM Retail Fund I, LLC
Schedule of net equity investment and share of net income or loss
Ownership %		55.00%
Investment in unconsolidated entities		$ 126,195		123,693
Number of contributed properties \| property	14
Aggregate deferred gain	$ 15,625
Amortization period	30 years
Unconsolidated Entities \| IAGM Retail Fund I, LLC \| Accounting Standard Update 2017-05
Schedule of net equity investment and share of net income or loss
Aggregate deferred gain			$ 12,756
Unconsolidated Entities \| Downtown Railyard Venture, LLC
Schedule of net equity investment and share of net income or loss
Ownership %		90.00%
Investment in unconsolidated entities		$ 30,049		57,183	$ 46,174
Debt instrument, face amount					$ 18,088
Stated interest rate (percent)					4.00%
Unconsolidated Entities \| Other unconsolidated entities
Schedule of net equity investment and share of net income or loss
Investment in unconsolidated entities		$ (112)		$ (112)