Note 3 - Investment Securities - Schedule of Investment Securities (Details) (Parentheticals)	9 Months Ended
Sep. 30, 2023
US Government Agencies Debt Securities [Member] \| Short-Term Investments [Member] \| Minimum [Member]
Maturity date	Oct. 31, 2023

Date of maturity of investment in debt security measured at amortized cost (held-to-maturity), in YYYY-MM-DD format.

No definition available.

Name:	us-gaap_HeldtomaturitySecuritiesDebtMaturitiesDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration