Notes Payable - Callable Medium-Term Notes (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Year two	$ 4,356,442
Year three	2,755,310
Year four	2,646,648
Total principal net of discounts	$ 23,838,159	$ 22,758,533
Weighted - average rate (as a percent)	1.45%
Year one
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.17%
Year two
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.10%
Year three
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.16%
Year four
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.16%
Call Option
Debt Instrument [Line Items]
Year one	$ 243,850
Year two	312,379
Year three	301,612
Year four	970,735
Thereafter	1,564,298
Total principal net of discounts	$ 3,392,874
Weighted - average rate (as a percent)	1.26%
Call Option \| Year one
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	0.42%
Call Option \| Year two
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	0.40%
Call Option \| Year three
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	0.92%
Call Option \| Year four
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.09%
Call Option \| Thereafter
Debt Instrument [Line Items]
Weighted - average rate (as a percent)	1.74%

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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