Note 5 - Allowance for Credit Losses on Loans and Nonperforming Assets - Ratios of Allowance for Loan Losses (Details)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Ratio of ACLL to the end of period loans, net of deferred fees and costs	1.04%	1.06%
Ratio of net charge-offs to average loans, net of deferred fees and costs	0.03%	0.02%

Percentage of allowance for credit loss to total financing receivable outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (1)
-Publisher SEC

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Namespace Prefix:	srt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant