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Fair Value Measurements - Other Investments and Unfunded Commitments (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
NAV of investments at fair value |  |
Unfunded Commitments | $ 129.4 | $ 127.2
Fair Value Measured at NAV |  |
NAV of investments at fair value |  |
Fair Value | 215.0 | 211.8
Controlling Interest | Fair Value Measured at NAV |  |
NAV of investments at fair value |  |
Fair Value | 145.9 | 137.6
Private equity funds |  |
NAV of investments at fair value |  |
Unfunded Commitments | 129.4 | 127.2
Private equity funds | Fair Value Measured at NAV |  |
NAV of investments at fair value |  |
Fair Value | $ 208.7 | 203.3
Life of funds (generally up to) | 15 years |
Investments in other strategies |  |
NAV of investments at fair value |  |
Unfunded Commitments | $ 0.0 | 0.0
Investments in other strategies | Fair Value Measured at NAV |  |
NAV of investments at fair value |  |
Fair Value | $ 6.3 | $ 8.5

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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 35 -Paragraph 54B -URI http://asc.fasb.org/extlink&oid=117332851&loc=SL7495116-110257 + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258 + Details
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