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Notes Payable (Details) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Debt Instrument [Line Items] |  |
Medium term notes called during the period | $ 762,400,000 | $ 47,100,000
Maximum borrowing capacity from U.S. Treasury | 1,500,000,000 |
Outstanding debt repurchases | $ 0 | 0
Discount Notes |  |
Debt Instrument [Line Items] |  |
Maturities of notes | 1 year |
Medium-term Notes | Minimum |  |
Debt Instrument [Line Items] |  |
Maturities of notes | 6 months |
Medium-term Notes | Maximum |  |
Debt Instrument [Line Items] |  |
Maturities of notes | 15 years |
Notes Payable to Banks |  |
Debt Instrument [Line Items] |  |
Maximum amount of discount notes outstanding at any month end | $ 2,600,000,000 | $ 1,900,000,000

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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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