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Commitments and Contingencies - Other commitments (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Commitments and Contingencies Disclosure [Abstract] |  |
Investment commitments | $ 2,100.0 | $ 1,700.0
Estimated purchase commitments, primarily related to software and computerized systems | $ 73.0 | $ 55.6

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- Definition Investment commitments primarily related to agreements entered into by the Company to invest in funds and separately managed accounts when called upon. + References No definition available. + Details
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Balance Type: | credit
Period Type: | instant

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- References No definition available. + Details
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- Definition Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(17)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(19)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(25)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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