Acquisitions, Goodwill and Intangible Assets 1 (Details) (USD $)	12 Months Ended
Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2010
Business Acquisition Contingent Consideration [Line Items]
Increase in goodwill due to contingent payment (TABS)	$ 12,334,000	$ 6,516,000
Parametric Portfolio Associates [Member]
Business Acquisition Contingent Consideration [Line Items]
Minority interest ownership percentage purchased by parent	1.70%	0.50%
Company's increase in profit interest percentage, during the period	2.90%	0.90%
Non-controlling interest holders capital ownership percentage, end of period	3.40%	5.20%	5.70%
Non-controlling interest holders profits interest, end of period	9.70%	11.40%	11.10%
Profits interest granted to non-controlling interest holders	1.10%	1.20%
Remaining non-controlling interest holders capital interest percentage that may be sold to the Company	3.40%
Remaining non-controlling interest holders right to profits, expressed as a percentage	5.70%
Purchase of non-controlling interests	17,000,000	4,300,000
Parametric Risk Advisors [Member]
Business Acquisition Contingent Consideration [Line Items]
Minority interest ownership percentage purchased by parent	10.00%	9.00%
Purchase of non-controlling interests	2,900,000	2,300,000
Company's capital ownership interest at the end of the period	70.00%	60.00%	51.00%
Atlanta Capital [Member]
Business Acquisition Contingent Consideration [Line Items]
Non-controlling interest holders profits interest, end of period	18.10%	16.90%	15.20%
Profits interest granted to non-controlling interest holders	1.20%	1.70%
Remaining non-controlling interest holders capital interest percentage that may be sold to the Company	10.30%
Fox Asset Management [Member]
Business Acquisition Contingent Consideration [Line Items]
Minority interest ownership percentage purchased by parent		16.00%
Company's capital ownership interest at the end of the period		100.00%	84.00%
Tax Advantaged Bond Strategies [Member]
Business Acquisition Contingent Consideration [Line Items]
Contingent payment made during the period	$ 12,300,000	$ 11,600,000

The contingent cash payment made to the selling group, resulting from the contingent consideration arrangement.

No definition available.

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- Definition

The parent entity's additional interest in net assets of the subsidiary purchased during the year, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

The remaining profits interest, expressed as a percentage, related to the interest in net assets held by the subsidiary that may be sold to the consolidating entity.

+ References

No definition available.

+ Details

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- Definition

The remaining interest, expressed as a percentage, in net assets held by the subsidiary that may be sold to the consolidating entity over a two year period.

+ References

No definition available.

+ Details

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- Definition

The non-controlling interest holders profits interest, expressed as a percentage at the end of the period.

+ References

No definition available.

+ Details

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- Definition

The increase in the consolidating entity's profits interest in the subsidiary, expressed as a percentage during the period.

+ References

No definition available.

+ Details

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- Definition

The increase in non-controlling interest holders profits interest, expressed as a percentage, related to the grants issued under the long-term equity incentive plan.

+ References

No definition available.

+ Details

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- Definition

Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph d

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4M

-URI http://asc.fasb.org/extlink&oid=18733213&loc=SL4591554-111686

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A7

-Appendix A

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- Definition

Change in the carrying value of goodwill. The change could be the result of new goodwill acquired, goodwill impairment, if any, goodwill written off related to the sale of a business or other adjustments to goodwill.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

-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 FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 72

-Subparagraph d

-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

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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