Acquired Properties - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Asset Acquisition [Abstract]
Transaction costs capitalized	$ 430	$ 1,911	$ 220

Asset Acquisition, Transaction Costs Capitalized During the Period

No definition available.

Name:	ivtp_AssetAcquisitionTransactionCostsCapitalizedDuringthePeriod
Namespace Prefix:	ivtp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration