v3.7.0.1

Securities - Additional Information (Details)	Mar. 31, 2017
Schedule Of Available For Sale Securities [Line Items]
Weighted average yield, total	0.90%
Agency Mortgage Backed Securities and Beneficial Interests in FHLMC Securitization
Schedule Of Available For Sale Securities [Line Items]
Weighted average yield, total	2.54%

X

- Definition

Available for sale securities weighted average yield.

+ References

No definition available.

+ Details

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Namespace Prefix:	ffwm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: