Cover - USD ($)	12 Months Ended
Cover - USD ($)	Dec. 31, 2023	Mar. 29, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K/A
Document Annual Report	true
Document Transition Report	false
Document Financial Statement Error Correction [Flag]	false
Entity Interactive Data Current	Yes
ICFR Auditor Attestation Flag	false
Amendment Flag	true
Amendment Description	EXPLANATORY NOTEPrinceton Capital Corporation (the “Company”) is filing this Amendment No. 1 on Form 10-K/A (the “Amendment”) to amend and restate certain items in its Annual Report on Form 10-K for the year ended December 31, 2023, originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on March 29, 2024 (the “Original Form 10-K”), to correct summarized financial information for Advantis Certified Staffing Solutions, Inc., an unconsolidated significant subsidiary of the Company (“Advantis”) in Note 10 to Notes to Financial Statements.
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Documents Incorporated by Reference [Text Block]	Certain exhibits previously filed with the Securities and Exchange Commission are incorporated by reference into Part IV of this report.
Entity Information [Line Items]
Entity Registrant Name	PRINCETON CAPITAL CORPORATION
Entity Central Index Key	0000845385
Securities Act File Number	814-00710
Entity Tax Identification Number	46-3516073
Entity Incorporation, State or Country Code	MD
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Public Float			$ 1,300,451
Entity Contact Personnel [Line Items]
Entity Address, Address Line One	800 Turnpike Street
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	North Andover
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01845
Entity Phone Fax Numbers [Line Items]
City Area Code	(978)
Local Phone Number	794-3366
Entity Listings [Line Items]
Title of 12(b) Security	None
Trading Symbol	None
Entity Common Stock, Shares Outstanding		120,486,061

PRINCETON CAPITAL CORP 10-K/A