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Fair Value Measurements - Fair Value Option on Consolidated VIEs and Equity Method Investments (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Commercial Mortgage Loans of Consolidated VIEs |  |  |  |  |
Fair Value Option, Quantitative Disclosures |  |  |  |  |
Pre-tax gain (loss) due to change in fair value of assets and liabilities for which the fair value option was elected |  | $ 0.1 |  | $ 0.1 |
Interest income |  | $ 0.1 |  | 0.3 |
Real Estate Ventures |  |  |  |  |
Fair Value Option, Quantitative Disclosures |  |  |  |  |
Fair value of assets for which fair value option was elected | $ 27.0 |  | $ 27.0 |  | $ 22.8
Pre-tax gain (loss) due to change in fair value of assets and liabilities for which the fair value option was elected | $ 1.7 |  | $ 4.0 | $ 2.3 |

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- Definition The fair value of commercial mortgage loans of consolidated variable interest entities and equity method investments for which the fair value option was elected. + References No definition available. + Details
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- Definition For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612 + Details
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- Definition Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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