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Variable Interest Entities - Summary of Silverton Loan Notes (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Movement in Silverton Loan Notes [Roll Forward] |  |  |  |  |  |
Total liability balance of Loan Notes, Beginning Balance |  |  | $ 277.9 | $ 235.0 |  |
Total change in fair value for the period | $ 9.8 | $ (9.8) | 3.6 | (13.7) |  |
Total distributed in the period |  |  | (144.7) | (108.7) |  |
Total liability balance of Loan Notes, Ending Balance | 128.7 | 143.4 | 128.7 | 143.4 |  |
Loan notes (long-term liabilities) |  |  |  |  | $ 125.7 | $ 140.6
Accrued expenses (current liabilities) |  |  |  |  | 3.0 | 2.8
Total aggregate unpaid balance | 128.7 | 143.4 | 277.9 | 235.0 | 128.7 | 143.4
Third party |  |  |  |  |  |
Movement in Silverton Loan Notes [Roll Forward] |  |  |  |  |  |
Total liability balance of Loan Notes, Beginning Balance |  |  | 223.4 | 190.6 |  |
Total change in fair value for the period |  |  | (3.6) | 13.7 |  |
Total distributed in the period |  |  | (115.9) | (89.3) |  |
Total liability balance of Loan Notes, Ending Balance | 103.9 | 115.0 | 103.9 | 115.0 |  |
Loan notes (long-term liabilities) |  |  |  |  | 101.5 | 112.7
Accrued expenses (current liabilities) |  |  |  |  | 2.4 | 2.3
Total aggregate unpaid balance | 103.9 | 115.0 | 223.4 | 190.6 | 103.9 | 115.0
Aspen Holdings |  |  |  |  |  |
Movement in Silverton Loan Notes [Roll Forward] |  |  |  |  |  |
Total liability balance of Loan Notes, Beginning Balance |  |  | 54.5 | 44.4 |  |
Total change in fair value for the period |  |  | (0.9) | 3.4 |  |
Total distributed in the period |  |  | (28.8) | (19.4) |  |
Total liability balance of Loan Notes, Ending Balance | 24.8 | 28.4 | 24.8 | 28.4 |  |
Loan notes (long-term liabilities) |  |  |  |  | 24.2 | 27.9
Accrued expenses (current liabilities) |  |  |  |  | 0.6 | 0.5
Total aggregate unpaid balance | $ 24.8 | $ 28.4 | 54.5 | 44.4 | $ 24.8 | $ 28.4
Aspen Holdings | Third party |  |  |  |  |  |
Movement in Silverton Loan Notes [Roll Forward] |  |  |  |  |  |
Total change in fair value for the period |  |  | $ (4.5) | $ 17.1 |  |

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- Definition The cash inflow from a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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