Notes Payable - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Medium term notes called during the period	$ 26,000,000	$ 2,000,000,000
Maximum borrowing capacity from U.S. Treasury	1,500,000,000
Outstanding debt repurchases	27,000,000	23,000,000
Gain on extinguishment of debt	$ 200,000	0
Discount Notes
Debt Instrument [Line Items]
Maturities of notes (in years)	1 year
Medium-term notes \| Minimum
Debt Instrument [Line Items]
Maturities of notes (in years)	6 months
Medium-term notes \| Maximum
Debt Instrument [Line Items]
Maturities of notes (in years)	25 years
Discount notes
Debt Instrument [Line Items]
Maximum amount of discount notes outstanding at any month end	$ 2,200,000,000	$ 2,400,000,000

Medium Term Notes Called During the Period

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period.

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