Consolidated Statements of Stockholders' Equity (Parentheticals) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022
Statement of Stockholders' Equity [Abstract]
Merger with Pioneer Bancshares, Inc. (issuance of treasury stock shares) (in shares)	1,557,054	1,557,054

Stock Issued During Period, Shares, Treasury Stock Reissued, Excluding Stock Option Exercise

No definition available.

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Namespace Prefix:	fcb_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration