Note 2 - Significant Accounting Policies - Tax Returns Subject to Examination (Details)	12 Months Ended
Mar. 31, 2023
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Open tax year	2019 2020 2021 2022 2023
State and Local Jurisdiction [Member] \| New Jersey Division of Taxation [Member]
Open tax year	2018 2019 2020 2021 2022 2023

Tax year that remains open to examination under enacted tax laws, in YYYY format.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15

Name:	us-gaap_OpenTaxYear
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:gYearListItemType
Balance Type:	na
Period Type:	duration