Regulatory - Additional Information (Detail)	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Description of minimum net capital requirements	The greater of $5,000 or 1/15 of aggregate indebtedness
Minimum net capital requirements (greater than $5,000 or 1/15 of aggregate indebtedness)	$ 5,000
Minimum net capital requirements (greater than $5,000 or 1/15 of aggregate indebtedness)	6.67%
Net capital	$ 21,200,000	$ 17,300,000
Excess net capital	$ 20,000,000	$ 14,700,000
Aggregate indebtedness to net capital ratio	0.9	2.2

Minimum Net Capital Required For Broker Dealer Subsidiary, Percent of Aggregate Indebtedness

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- Definition

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

+ References

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

+ Details

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- Definition

Minimum amount of net capital required to be maintained by broker-dealer subsidiary to engage in security transaction, calculated under Aggregate Indebtedness Standard.

+ References

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

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- Definition

Amount of net capital of broker-dealer.

+ References

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

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- References

No definition available.

+ Details

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- Definition

Describes the capital requirements for trusts assets under management.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117337116&loc=d3e65217-112826

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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