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Organization And Nature Of Operations (Narrative) (Details) $ / shares in Units, $ in Millions |  | 9 Months Ended |
--- | --- | --- | ---
Sep. 01, 2017 $ / shares | Sep. 30, 2018 USD ($) segment $ / shares | Dec. 31, 2017 $ / shares
Securities [Line Items] |  |  |
Reverse stock split | 10 |  |
Common Stock, par value | $ / shares | $ 0.01 | $ 0.01 | $ 0.01
Common Stock, pre split par value | $ / shares | $ 0.001 |  |
Assets under management | $ |  | $ 3,120 |
Number of Operating Segments | segment |  | 3 |
CDOs [Member] |  |  |
Securities [Line Items] |  |  |
Assets under management | $ |  | $ 2,690 |
Assets under management which are collateralized debt obligations percentage |  | 86.00% |

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