Note 15 - Net Capital Requirements of Broker Dealer Subsidiary (Details Textual)	Sep. 30, 2020 USD ($)
National Securities [Member]
Broker-Dealer, Net Capital, Total	$ 3,812,891
Broker-Dealer, Excess Net Capital, Alternative Standard, Total	2,812,891
National Securities [Member] \| SEC Requirement [Member]
Broker-Dealer, Minimum Net Capital Required, Aggregate Indebtedness Standard, Total	1,000,000
Winslow, Evans & Crocker [Member]
Broker-Dealer, Net Capital, Total	467,947
Broker-Dealer, Excess Net Capital, Alternative Standard, Total	$ 305,992
Broker-Dealer, Minimum Net Capital Required, Aggregate Indebtedness Standard to Net Capital Ratio, Actual	5.2
Winslow, Evans & Crocker [Member] \| SEC Requirement [Member]
Broker-Dealer, Minimum Net Capital Required, Aggregate Indebtedness Standard, Total	$ 161,955
Broker-Dealer, Minimum Net Capital Required, Maximum Aggregate Indebtedness Standard to Net Capital Ratio	15
Financial Services International Corporation [Member]
Broker-Dealer, Minimum Net Capital Required, Aggregate Indebtedness Standard to Net Capital Ratio, Actual	0.2
Financial Services International Corporation [Member] \| SEC Requirement [Member]
Broker-Dealer, Net Capital, Total	$ 117,538
Broker-Dealer, Excess Net Capital, Alternative Standard, Total	112,538
Broker-Dealer, Minimum Net Capital Required, Aggregate Indebtedness Standard, Total	$ 5,000

The actual ratio of aggregate indebtedness to net capital, calculated under Aggregate Indebtedness Standard.

No definition available.

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Maximum ratio of aggregate indebtedness to net capital, calculated under Aggregate Indebtedness Standard.

No definition available.

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Amount of net capital in excess of minimum required net capital, calculated under Alternative Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Minimum amount of net capital required to be maintained by broker-dealer and its subsidiary, calculated under Aggregate Indebtedness Standard.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Amount of net capital of broker-dealer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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