Available for Sale Securities (Proceeds from Sales of Available for Sale Securities) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Available for Sale Securities
Proceeds from sale of securities	$ 3	$ 1,034
Gross realized gains on sale of securities	0	17
Gross realized losses on sale of securities	$ 0	$ (2)

Gross proceeds from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

No definition available.

+ Details

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Namespace Prefix:	ffbw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

+ Details

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Balance Type:	credit
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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- References

No definition available.

+ Details

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