RCap Regulatory Requirements - Additional Information (Detail) - RCap	Jun. 30, 2017 USD ($)
RCAP Regulatory Requirements:
Minimum net capital requirement	$ 300,000
Regulatory net capital	392,500,000
Regulatory net capital, excess net capital	$ 392,200,000

Regulatory Requirements [Line Items]

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- Definition

The amount of net capital in excess of the minimum required net capital.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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 entity's broker-dealer subsidiary to engage in securities transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

+ Details

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- Definition

Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Details

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