v2.4.0.6

Fair Value Measurements (Company's Portfolio of Other Investments Measured Using Net Asset Valuations) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2012 Days
Fair Value | $ 709,615
Unfunded Commitments | 105,235
Private equity partnerships [Member] |
Fair Value | 389,451
Unfunded Commitments | 100,120
Senior secured bank loan funds [Member] |
Fair Value | 266,141
Unfunded Commitments | 5,115
Non-U.S. fixed income funds [Member] |
Fair Value | 31,713
Unfunded Commitments | 0
Redemption Frequency | Bi-monthly
Redemption Notice Period, Minimum | 5
Redemption Notice Period, Maximum | 20
Hedge funds [Member] |
Fair Value | 22,310
Unfunded Commitments | $ 0
Redemption Frequency | Annually, Bi-annually
Redemption Notice Period, Minimum | 45
Redemption Notice Period, Maximum | 90

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- Definition Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period, Maximum + References No definition available. + Details
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- Definition Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period, Minimum + References No definition available. + Details
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- Definition This element represents the total fair market value of investments in certain entities that calculate net asset value per share (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements, but may also be used in both the balance sheet and disclosure in the same submission. This item represents alternative investments as of the balance sheet date which may include investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds, and any other investment in which investee management calculates net asset value per share as the primary metric for investment value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph a -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph a -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Subparagraph (a) -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258 + Details
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- Definition States the frequency (for example, annually, semi-annually, quarterly) with which the entity can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category. + 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=6925170&loc=SL6742756-110258 + Details
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- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (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 (c) -URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258 + Details
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