Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 28, 2020	Jun. 30, 2019
Document Information [Line Items]
Entity Registrant Name	LIMESTONE BANCORP, INC.
Entity Central Index Key	0001358356
Trading Symbol	lmst
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Interactive Data Current	Yes
Entity Public Float			$ 79,993,646
Entity Shell Company	false
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Title of 12(b) Security	Common Stock, no par value
Nonvoting Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		1,220,000
Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		6,271,143