Regulatory Requirements - Additional Information (Detail) (USD $)	6 Months Ended
Jun. 30, 2012
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum net capital requirements	$ 5,000
Description of minimum net capital requirements	The greater of $5,000 or 1/15 of aggregate indebtedness
Net capital	9,100,000
Excess net capital	$ 8,900,000
Aggregate indebtedness to net capital ratio	0.37

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Describes the capital requirements for trusts assets under management.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7881181&loc=d3e65217-112826

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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

-Number 240

-Section 1

-Paragraph 1

-Subparagraph i

-Article 15c3

-Subsection a

+ 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

-Number 240

-Section 1

-Paragraph 1

-Subparagraph i

-Article 15c3

-Subsection a

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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

-Number 240

-Section 1

-Paragraph 1

-Subparagraph ii

-Article 15c3

-Subsection a

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Paragraph 80

-Subparagraph Exhibit 4-8

-IssueDate 2006-05-01

-Chapter 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-BRD

-Paragraph 80

-Subparagraph Exhibit 4-8, 15

-IssueDate 2006-05-01

-Chapter 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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