v3.26.1
Document And Entity Information
Jul. 30, 2026
Document Information Line Items  
Entity Central Index Key 0000020639
Document Type 8-K
Document Period End Date Jul. 30, 2026
Entity Registrant Name AMBASE CORPORATION
Entity Incorporation, State or Country Code DE
Entity File Number 1-07265
Entity Tax Identification Number 95-2962743
Entity Address, Address Line One 7857 WEST SAMPLE ROAD
Entity Address, Address Line Two SUITE 134
Entity Address, City or Town CORAL SPRINGS
Entity Address, State or Province FL
Entity Address, Postal Zip Code 33065
City Area Code 201
Local Phone Number 265-0169
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Amendment Flag false