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Business Combinations (Narrative) (Details) - HNP Capital [Member] - USD ($) $ in Millions | Jun. 01, 2018 | Jun. 30, 2018
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Business Acquisition [Line Items] |  |
Assets under management |  | $ 344.0
Consideration for acquisition in cash | $ 5.1 |
Goodwill | 2.6 |
Identified intangible assets | $ 2.5 |

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