Fair Value Measurements of Other Financial Instruments (Details) (USD $)	Jan. 31, 2013	Oct. 31, 2012
Carrying And Fair Value [Line Items]
Carrying value of other investments	$ 7,470,000	$ 7,470,000
Carrying value of debt	500,000,000	500,000,000
Carrying value of non-controlling capital interest in ACM Holdings	6,600,000	6,600,000
Carrying value of other assets related to Hexavest option	8,312,000	8,307,000
Level 1 [Member]
Carrying And Fair Value [Line Items]
Fair value of debt	598,331,000	604,316,000
Level 3 [Member]
Carrying And Fair Value [Line Items]
Fair value of other investments	7,470,000	7,470,000
Fair value of non-controlling capital interest in ACM Holdings	6,600,000	6,600,000
Fair value of other assets related to Hexavest option	$ 8,312,000	$ 8,307,000

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Carrying amount of the capital interests owned by noncontrolling partners of a limited liability company included in the entity's consolidated financial statements.

+ References

No definition available.

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- Definition

Fair value of the capital interests owned by noncontrolling partners of a limited liability company included in the entity's consolidated financial statements.

+ References

No definition available.

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The fair value of other investments held by the Company.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

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-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of assets categorized as other which are not in and of themselves material enough to require separate disclosure.

+ References

No definition available.

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The sum of the carrying amounts, as of the balance sheet date, of assets which have not been itemized or categorized in the footnotes to the financial statements and are a component of Other Assets (OtherAssets).

+ References

No definition available.

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- Definition

Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

-Paragraph a

-Subparagraph 1(g)

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