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Fair Value Measurement (Investments in LLCs and Limited Partnerships Footnote) (Details) | 3 Months Ended
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Mar. 31, 2017
Long equity fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Investment redemption notice period | 15 days
Payment period for redemption of LP valued at NAV | 10 days
Long/Short Equity Funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Payment period for redemption of LP valued at NAV | 30 days
Redemption percentage of LP at NAV for which initial payment is limited | 90.00%
Non-public equity funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Liquidating investments remaining period | 9 years
Structured credit fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Investment redemption notice period | 90 days
Long/Short commodities fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Investment redemption notice period | 30 days
Minimum [Member] | Secured debt fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Liquidating investments remaining period | 3 years
Minimum [Member] | Long/Short Equity Funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Investment redemption notice period | 30 days
Maximum [Member] | Secured debt fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Liquidating investments remaining period | 8 years
Maximum [Member] | Long/Short Equity Funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Investment redemption notice period | 90 days
Maximum [Member] | Long/Short commodities fund [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Payment period for redemption of LP valued at NAV | 30 days

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- Definition The number of days required for payment upon redemption of a particular LP that is valued at NAV. + References No definition available. + Details
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- Definition The redemption percentage of a particular LP valued at NAV above which initial payment is limited. + References No definition available. + Details
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- Definition Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258 + 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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- Definition Estimate remaining period the underlying assets are expected to be liquidated by the investees for investments for which net asset value per share is calculated (including by unit, membership interest, or other ownership interest unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258 + Details
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