Notes Payable - Earliest Interest Reset Date of Borrowing Outstanding (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
2023	$ 3,692,620	$ 3,004,203
2024	2,513,348	2,809,551
2025	1,684,685	927,119
Total principal net of discounts	$ 22,350,985	$ 21,795,677
Short-term debt, weighted average rate (as a percent)	0.40%	0.59%
Weighted - average rate (as a percent)	1.14%	1.37%
Total weighted - average rate (as a percent)	0.87%	0.98%
2021
Debt Instrument [Line Items]
2021	$ 7,159,124
Short-term debt, weighted average rate (as a percent)	0.22%
2022
Debt Instrument [Line Items]
2022	$ 3,242,709
Weighted - average rate (as a percent)	0.89%
2023
Debt Instrument [Line Items]
2023	$ 3,267,608
Weighted - average rate (as a percent)	0.98%
2024
Debt Instrument [Line Items]
2024	$ 1,870,603
Weighted - average rate (as a percent)	0.98%
2025
Debt Instrument [Line Items]
2025	$ 1,633,640
Weighted - average rate (as a percent)	0.90%
Thereafter
Debt Instrument [Line Items]
Thereafter	$ 5,177,301
Weighted - average rate (as a percent)	1.63%

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Weighted average interest rate of debt outstanding.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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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 fourth 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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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 third 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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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 second 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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