Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 08, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Entity Registrant Name	Trinity Place Holdings Inc.
Entity Central Index Key	0000724742
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Trading Symbol	TPHS
Entity Common Stock, Shares Outstanding		31,451,796