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Borrowings - Securitizations (Details) - USD ($) | 1 Months Ended |  |
--- | --- | --- | ---
Aug. 31, 2020 | Feb. 29, 2020 | Jun. 30, 2019 | Mar. 31, 2019 | Sep. 30, 2020 | Dec. 31, 2019
Securities Financing Transaction [Line Items] |  |  |  |  |  |
Total Issued |  |  |  |  | $ 1,343,000,000 | $ 1,110,000,000
Total loan and accrued interest amount securitized at inception on-balance sheet term securitization |  |  |  |  | $ 1,463,230,000 | $ 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 |  |  |  |
2020-B |  |  |  |  |  |
Securities Financing Transaction [Line Items] |  |  |  |  |  |
Total Issued | $ 707,000,000 |  |  |  |  |
Basis spread on variable rate | 1.30% |  |  |  |  |
Weighted Average Life | 4 years 1 month 20 days |  |  |  |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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