v3.25.3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) | 9 Months Ended
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Sep. 30, 2025 subsidiary
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES |
Number of inactive wholly owned subsidiaries | 2

X
- Definition Number of inactive wholly owned subsidiaries. + References No definition available. + Details
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Namespace Prefix: | ffwm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration