Document And Entity Information
Apr. 20, 2020
Document Information [Line Items]  
Entity, Registrant Name Safeguard Scientifics, Inc.
Document, Type 8-K
Document, Period End Date Apr. 20, 2020
Entity, Incorporation, State or Country Code PA
Entity, File Number 1-5620
Entity, Tax Identification Number 23-1609753
Entity, Address, Address Line One One Radnor Corp. Ctr., Suite 110
Entity, Address, Address Line Two 100 Matsonford Rd.
Entity, Address, City or Town Radnor
Entity, Address, State or Province PA
Entity, Address, Postal Zip Code 19087
City Area Code 610
Local Phone Number 293-0600
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock
Trading Symbol SFE
Security Exchange Name NYSE
Entity, Emerging Growth Company false
Amendment Flag false
Entity, Central Index Key 0000086115