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Investments In Unconsolidated Subsidiaries - Additional information (Detail) - Maximum [Member] | Sep. 30, 2017
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Global Investment Management [Member] |
Schedule Of Equity Method Investments [Line Items] |
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage | 5.00%
Development Services [Member] |
Schedule Of Equity Method Investments [Line Items] |
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage | 10.00%
Other [Member] |
Schedule Of Equity Method Investments [Line Items] |
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage | 50.00%

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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