Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Mar. 23, 2023	Jun. 30, 2022
Document Information [Line Items]
Entity, Registrant Name	BIOCARDIA, Inc.
Document, Type	10-K/A
Document, Annual Report	true
Current Fiscal Year End Date	--12-31
Document, Fiscal Period Focus	FY
Document, Fiscal Year Focus	2022
Document, Period End Date	Dec. 31, 2022
Document, Transition Report	false
Entity, File Number	0-21419
Entity, Incorporation, State or Country Code	DE
Entity, Tax Identification Number	23-2753988
Entity, Address, Address Line One	320 Soquel Way
Entity, Address, City or Town	Sunnyvale
Entity, Address, State or Province	CA
Entity, Address, Postal Zip Code	94085
City Area Code	650
Local Phone Number	226-0120
Entity, Well-known Seasoned Issuer	No
Entity, Voluntary Filers	No
Entity, Current Reporting Status	Yes
Entity, Interactive Data, Current	Yes
Entity, Filer Category	Non-accelerated Filer
Entity, Small Business	true
Entity, Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity, Shell Company	false
Entity, Public Float			$ 19.8
Entity, Common Stock Shares, Outstanding		20,183,014
Auditor Name	PKF San Diego, LLP
Auditor Location	San Diego, California
Auditor Firm ID	27
Amendment Description	This Amendment No. 1 on Form 10-K/A (this “Amendment” or “Form 10-K/A”) to amend the Annual Report on Form 10-K of BioCardia, Inc. (“BioCardia,” the “Company,” “we,” “us,” or “our”) for the fiscal year ended December 31, 2022, originally filed with the Securities and Exchange Commission (the “SEC”) on March 29, 2023 (the “Original Report”), is being filed for the purpose of including the information required to be disclosed by Part III of Form 10-K. This information was previously omitted from the Original Report in reliance on General Instruction G(3) to Form 10-K, which permits the information in the above referenced items to be incorporated in the Form 10-K by reference from our definitive proxy statement if such proxy statement is filed no later than 120 days after our fiscal year-end. The reference on the cover page of the Original Report to the incorporation by reference to portions of our definitive proxy statement into Part III of the Original Report has been deleted. This Amendment No. 1 hereby amends and restates in their entirety the cover page and Items 10 through 14 of Part III of the Original Report.   As required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended, in connection with the filing of this Form 10-K/A, our Chief Executive Officer and Chief Financial Officer are providing Rule 13a-14(a) certifications as included herein. We are amending Item 15 of Part IV solely to reflect the inclusion of these certifications.   Except as described above, this Form 10-K/A does not modify or update disclosure in, or exhibits to, the Original Report. Furthermore, this Form 10-K/A does not change any previously reported financial results, nor does it reflect events occurring after the filing date of the Original Report. Information not affected by this Form 10-K/A remains unchanged and reflects the disclosures made at the time the Original Report was filed.
Amendment Flag	true
Entity, Central Index Key	0000925741
CommonStockParValue0001 Custom [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.001
Trading Symbol	BCDA
Security Exchange Name	NASDAQ
WarrantToPurchaseCommonStock Custom [Member]
Document Information [Line Items]
Title of 12(b) Security	Warrant to Purchase Common Stock
Trading Symbol	BCDAW
Security Exchange Name	NASDAQ