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Borrowings - Securitizations (Details) - USD ($) | 1 Months Ended |  |
--- | --- | --- | ---
Feb. 29, 2020 | Jun. 30, 2019 | Mar. 31, 2019 | Mar. 31, 2020 | Dec. 31, 2019
Securities Financing Transaction [Line Items] |  |  |  |  |
Total Issued |  |  |  | $ 636,000,000 | $ 1,110,000,000
Total loan and accrued interest amount securitized at inception on-balance sheet term securitization |  |  |  | $ 676,089,000 | $ 1,208,963,000
2019-A |  |  |  |  |
Securities Financing Transaction [Line Items] |  |  |  |  |
Total Issued |  |  | $ 453,000,000 |  |
Basis spread on variable rate |  |  |  | 0.92% |
Weighted Average Life |  |  | 4 years 3 months 3 days |  |
2019-B |  |  |  |  |
Securities Financing Transaction [Line Items] |  |  |  |  |
Total Issued |  | $ 657,000,000 |  |  |
Basis spread on variable rate |  |  |  | 1.01% |
Weighted Average Life |  | 4 years 4 months 28 days |  |  |
2020-A |  |  |  |  |
Securities Financing Transaction [Line Items] |  |  |  |  |
Total Issued | $ 636,000,000 |  |  |  |
Basis spread on variable rate | 0.88% |  |  |  |
Weighted Average Life | 4 years 2 months 4 days |  |  |  |

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