Note 5 - Mortgage Loan Servicing - Mortgage Loans Serviced for Others (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Mortgage loans serviced for others	$ 1,404,388	$ 1,376,143
Federal Home Loan Mortgage Corporation [Member]
Mortgage loans serviced for others	1,341,602	1,345,312
Federa lHome Loan Bank [Member]
Mortgage loans serviced for others	$ 62,786	$ 30,831

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4

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