Loans Loans - Payment Status (Details) - USD ($) $ in Thousands	May 31, 2019	May 31, 2018
Payment Status of Loans
Current	$ 25,905,664	$ 25,167,494
Past Due	0	0
Loans and Leases Receivable, Net of Deferred Income	25,905,664	25,167,494	[1]
Non-accrual loans	$ 0	$ 0
As a % of total loans
Current	100.00%	100.00%
30-89 days past due	0.00%	0.00%
90 days or more past due	0.00%	0.00%
Total past due	0.00%	0.00%
Total financing receivables	100.00%	100.00%
Non-accrual loans	0.00%	0.00%
CFC
Payment Status of Loans
Current	$ 24,817,676	$ 24,017,919
Past Due	0	0
Loans and Leases Receivable, Net of Deferred Income	24,817,676	24,017,919	[1]
Non-accrual loans	0	0
CFC | Distribution
Payment Status of Loans
Current	20,155,266	19,551,511
Past Due	0	0
Loans and Leases Receivable, Net of Deferred Income	20,155,266	19,551,511	[1]
Non-accrual loans	0	0
CFC | Power supply
Payment Status of Loans
Current	4,578,841	4,397,353
Past Due	0	0
Loans and Leases Receivable, Net of Deferred Income	4,578,841	4,397,353	[1]
Non-accrual loans	0	0
CFC | Statewide and associate
Payment Status of Loans
Current	83,569	69,055
Loans and Leases Receivable, Net of Deferred Income	83,569	69,055	[1]
NCSC
Payment Status of Loans
Current	742,888	786,457
Past Due	0
Loans and Leases Receivable, Net of Deferred Income	742,888	786,457	[1]
Non-accrual loans	0	0
RTFC
Payment Status of Loans
Current	345,100	363,118
Past Due		0
Loans and Leases Receivable, Net of Deferred Income	345,100	363,118	[1]
Non-accrual loans	0	0
30-89 Days Past Due
Payment Status of Loans
Past Due	0	0
30-89 Days Past Due | CFC
Payment Status of Loans
Past Due	0	0
30-89 Days Past Due | CFC | Distribution
Payment Status of Loans
Past Due	0	0
30-89 Days Past Due | NCSC
Payment Status of Loans
Past Due	0
30-89 Days Past Due | RTFC
Payment Status of Loans
Past Due		0
90 Days or More Past Due
Payment Status of Loans
Past Due	0	0
90 Days or More Past Due | CFC
Payment Status of Loans
Past Due	0	0
90 Days or More Past Due | CFC | Distribution
Payment Status of Loans
Past Due	0	0
90 Days or More Past Due | CFC | Power supply
Payment Status of Loans
Past Due	0
90 Days or More Past Due | NCSC
Payment Status of Loans
Past Due	$ 0
90 Days or More Past Due | RTFC
Payment Status of Loans
Past Due		$ 0

[1] The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.