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Related Parties - Narrative (Details) - Pension Plans - Investment Management Services for Defined Benefit Plan - FS&C - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2020 | Jun. 30, 2019
Related Party Transaction [Line Items] |  |
Assets under management, carrying amount | $ 133.5 |
Investment expenses | $ 0.4 | $ 0.4

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- Definition Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
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