Long-Term Debt (Details Textual) (USD $)									9 Months Ended				9 Months Ended
	Feb. 28, 2014	May 31, 2013	Nov. 30, 2013 Subsequent Event [Member]	Feb. 28, 2014 Federal Agricultural Mortgage Corporation	May 31, 2013 Federal Agricultural Mortgage Corporation	Jun. 30, 2013 2.35% Collateral Trust Bonds Due 2020	Nov. 30, 2013 3.4% Collateral Trust Bonds Due 2023	Dec. 16, 2013 4.75% Collateral Trust Bonds Due March 1, 2014	Feb. 28, 2014 Committed Loan Facilities Federal Financing Bank Loan Guarantees RUS	Nov. 21, 2013 Committed Loan Facilities Federal Financing Bank Loan Guarantees RUS	Jan. 01, 2014 1.10% Collateral Trust Bonds Due 2017	Jan. 01, 2014 2.15% Collateral Trust Bonds Due 2019	Feb. 28, 2014 Committed Loan Facilities Federal Financing Bank	Feb. 28, 2014 Unsecured Notes Payable	May 31, 2013 Unsecured Notes Payable	Feb. 28, 2014 Unsecured Notes Payable Federal Financing Bank	May 31, 2013 Unsecured Notes Payable Federal Financing Bank	Feb. 28, 2014 Secured notes payable Federal Agricultural Mortgage Corporation	May 31, 2013 Secured notes payable Federal Agricultural Mortgage Corporation
Debt Instrument [Line Items]
Long Term Debt, Gross, Noncurrent														$ 4,032,167,000	$ 3,709,074,000	$ 3,999,000,000	$ 3,674,000,000	$ 1,523,000,000	$ 1,542,000,000
Debt Instrument Maximum Borrowing Capacity				3,900,000,000						500,000,000
Proceeds from Issuance of Debt													325,000,000
Debt Instrument, Interest Rate, Stated Percentage						2.35%	3.40%	4.75%			1.10%	2.15%
Debt Instrument, Repurchased Face Amount								150,000,000
Debt Instrument, Face Amount								600,000,000
Debt Instrument Carrying Amount Issued						400,000,000	400,000,000				300,000,000	300,000,000
Debt Instrument, Term									20 years
Debt Instrument, Unused Borrowing Capacity, Amount													924,000,000
Unamortized Premium And Issuance Cost			1,500,000
Short-term Debt, Total	4,785,334,000	4,050,132,000		26,000,000	741,000,000
Long-term Debt				$ 1,497,000,000	$ 801,000,000