Note 4 - Loans and the Allowance for Credit Losses - Balance of Nonaccrual Loans By Loan Category (Details) $ in Thousands	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Total nonaccrual	$ 13,652	$ 4,105
Past due 90 days or more and still accruing	$ 0	$ 0
Number of loans	5	1
Nonaccrual, with allowance, amortized cost	$ 3,043	$ 55
Nonaccrual, with allowance, allowance	959	29
Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	10,609	4,050
Total nonaccrual	13,652	4,105
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Total nonaccrual	353	355
Past due 90 days or more and still accruing	$ 0	$ 0
Number of loans	1	1
Nonaccrual, with allowance, amortized cost	$ 52	$ 55
Nonaccrual, with allowance, allowance	28	29
Commercial Portfolio Segment [Member] \| Commercial Loans [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	301	302
Total nonaccrual	353	355
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Total nonaccrual	9,905	567
Past due 90 days or more and still accruing	$ 0	$ 0
Number of loans	4	0
Nonaccrual, with allowance, amortized cost	$ 2,991	$ 0
Nonaccrual, with allowance, allowance	931	0
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	6,914	567
Total nonaccrual	9,905	567
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Total nonaccrual	1,281	1,579
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	1,281	1,579
Total nonaccrual	1,281	1,579
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Total nonaccrual	0	0
Past due 90 days or more and still accruing	0	0
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	0	0
Total nonaccrual	0	0
Past due 90 days or more and still accruing	0	0
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Total nonaccrual	227	83
Past due 90 days or more and still accruing	0	0
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	227	83
Total nonaccrual	227	83
Past due 90 days or more and still accruing	0	0
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Total nonaccrual	1,089	650
Past due 90 days or more and still accruing	0	0
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	1,089	650
Total nonaccrual	1,089	650
Past due 90 days or more and still accruing	0	0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Total nonaccrual	790	792
Past due 90 days or more and still accruing	0	0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	790	792
Total nonaccrual	790	792
Past due 90 days or more and still accruing	0	0
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Total nonaccrual	7	79
Past due 90 days or more and still accruing	0	0
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| Nonperforming Financial Instruments [Member]
Nonaccrual with no allowance for credit losses	7	77
Total nonaccrual	7	79
Past due 90 days or more and still accruing	$ 0	$ 0

Represents the allowance for credit losses on nonaccrual financing receivables.

No definition available.

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Namespace Prefix:	plbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amortized cost of financing receivable on nonaccrual status with allowance for credit loss. Excludes net investment in lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	plbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the number of loans in nonaccrual status with allowance for credit loss.

+ References

No definition available.

+ Details

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Namespace Prefix:	plbc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit losses. Excludes net investment in lease.

+ References

No definition available.

+ Details

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Namespace Prefix:	plbc_
Data Type:	xbrli:monetaryItemType
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- Definition

Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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