Derivative Instruments and Hedging Activities - Rating Triggers (Details) - Interest rate swaps $ in Thousands	Feb. 28, 2022 USD ($)
Derivative [Line Items]
Notional Amount	$ 5,855,111
Payable Due from CFC	(247,052)
Receivable Due to CFC	0
Net Payable	(247,052)
Moody's, A3 Rating Standard Poor's A- Rating
Derivative [Line Items]
Notional Amount	36,110
Payable Due from CFC	(5,726)
Receivable Due to CFC	0
Net Payable	(5,726)
Moodys Baa 1 Rating Standard Poor's BBB Plus Rating
Derivative [Line Items]
Notional Amount	5,524,597
Payable Due from CFC	(231,423)
Receivable Due to CFC	0
Net Payable	(231,423)
Moody's Baa 2 Rating Standard Poor's BBB Rating
Derivative [Line Items]
Notional Amount	294,404
Payable Due from CFC	(9,903)
Receivable Due to CFC	0
Net Payable	$ (9,903)