Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Mar. 25, 2020	Jan. 17, 2020
Cover [Abstract]
Entity Registrant Name	FFBW, Inc.
Entity Central Index Key	0001709017
Document Type	10-K
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Amendment Flag	false
Entity Public Float			$ 82.8
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		7,704,875