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Disaggregated Revenue and Deferred Revenue - Schedule of Other Income by Component (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Disaggregation of Revenue [Line Items] |  |  |  |
Borrower late fee income | $ 3,196 | $ 3,253 | $ 9,870 | $ 8,994
Gain on investments and notes receivable, net of losses | 1,948 | 2,503 | 5,779 | 10,291
Other | 5,458 | 7,978 | 14,808 | 16,681
Other income | 13,439 | 16,673 | 38,658 | 44,808
Management fees |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 2,084 | 1,756 | 6,007 | 4,673
Investment advisory services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 753 | $ 1,183 | $ 2,194 | $ 4,169

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