Notes Payable - Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Due within one year:
Current portion of medium-term notes	$ 8,034,175	$ 6,986,799
Weighted - average rate (as a percent)	2.31%	0.45%
Medium-term notes due in:
Two years	$ 4,072,740
Three years	3,506,480
Four years	2,967,625
Five years	2,361,197
Thereafter	4,057,982
Total due after one year	16,966,024
Total principal net of discounts	25,000,199	$ 22,758,533
Hedging adjustments	(531,086)	(44,762)
Total	$ 24,469,113	22,713,771
Weighted - average rate (as a percent)	2.15%
Total weighted - average rate (as a percent)	2.20%
Two years
Medium-term notes due in:
Weighted - average rate (as a percent)	1.71%
Three years
Medium-term notes due in:
Weighted - average rate (as a percent)	2.10%
Four years
Medium-term notes due in:
Weighted - average rate (as a percent)	1.44%
Five years
Medium-term notes due in:
Weighted - average rate (as a percent)	3.12%
Thereafter
Medium-term notes due in:
Weighted - average rate (as a percent)	2.60%
Discount notes
Due within one year:
Current portion of medium-term notes	$ 565,578	$ 2,167,979
Weighted - average rate (as a percent)	3.91%	0.05%
Short-term debt, average outstanding during the quarter	$ 1,325,026	$ 1,822,714
Weighted - average rate, average outstanding during the quarter (as a percent)	0.96%	0.08%
Medium-term notes
Due within one year:
Current portion of medium-term notes	$ 2,547,733	$ 837,580
Weighted - average rate (as a percent)	3.54%	0.09%
Short-term debt, average outstanding during the quarter	$ 1,442,932	$ 1,956,870
Weighted - average rate, average outstanding during the quarter (as a percent)	2.11%	0.12%
Medium-term notes due in:
Two years		$ 4,179,985
Three years		2,554,906
Four years		2,119,805
Five years		2,810,894
Thereafter		4,106,144
Total due after one year		$ 15,771,734
Weighted - average rate (as a percent)		1.10%
Total weighted - average rate (as a percent)		0.90%
Medium-term notes | Two years
Medium-term notes due in:
Weighted - average rate (as a percent)		0.81%
Medium-term notes | Three years
Medium-term notes due in:
Weighted - average rate (as a percent)		0.87%
Medium-term notes | Four years
Medium-term notes due in:
Weighted - average rate (as a percent)		0.85%
Medium-term notes | Five years
Medium-term notes due in:
Weighted - average rate (as a percent)		1.07%
Medium-term notes | Thereafter
Medium-term notes due in:
Weighted - average rate (as a percent)		1.69%
Current portion of medium-term notes
Due within one year:
Current portion of medium-term notes	$ 4,920,864	$ 3,981,240
Weighted - average rate (as a percent)	1.49%	0.75%