Note 9 - Fair Value Measurement (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Impairment of Collateral Dependent Loans	$ 485	$ 109	$ 1,300	$ 1,000

Represents the impairment of collateral-dependent loans.

No definition available.

Name:	plbc_ImpairmentOfCollateralDependentLoans
Namespace Prefix:	plbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration