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 | Mar. 31, 2013
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Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Fair Value | $ 577,783
Unfunded Commitments | 122,194
Private equity partnerships [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Fair Value | 345,666
Unfunded Commitments | 84,958
Senior secured bank loan funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Fair Value | 204,114
Unfunded Commitments | 17,506
Hedge funds [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Fair Value | 5,219
Unfunded Commitments | 0
Miscellaneous other investments [Member] |
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] |
Fair Value | 22,784
Unfunded Commitments | $ 19,730

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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=7578670&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 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7578670&loc=SL6742756-110258 + Details
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Period Type: | instant

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- 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=7578670&loc=SL6742756-110258 + Details
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Balance Type: | credit
Period Type: | instant