Notes Payable - Earliest Interest Reset Date of Borrowing Outstanding (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2022	$ 3,764,817	$ 3,700,835
2023	1,839,291	1,594,709
2024	1,204,584	1,205,276
Total	$ 21,421,550	$ 19,098,648
Short-term debt, weighted average rate (as a percent)	0.76%	1.84%
Weighted - Average Rate (as a percent)	1.61%	2.28%
Total Weighted - Average Rate (as a percent)	1.18%	2.05%
2020
Debt Instrument [Line Items]
Short-term debt	$ 11,227,000
Short-term debt, weighted average rate (as a percent)	0.48%
2021
Debt Instrument [Line Items]
2021	$ 3,047,823
Weighted - Average Rate (as a percent)	1.79%
2022
Debt Instrument [Line Items]
2022	$ 1,745,399
Weighted - Average Rate (as a percent)	1.74%
2023
Debt Instrument [Line Items]
2023	$ 1,706,568
Weighted - Average Rate (as a percent)	1.88%
2024
Debt Instrument [Line Items]
2024	$ 965,056
Weighted - Average Rate (as a percent)	1.86%
Thereafter
Debt Instrument [Line Items]
Long-Term Debt, Maturity, after Year Four	$ 2,729,704
Weighted - Average Rate (as a percent)	2.31%

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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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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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