CONSOLIDATED STATEMENTS OF CAPITALIZATION (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Secured Long-term debt:
Total Secured Long-term, net	$ 6,229,293	$ 5,670,449
Unsecured bank term loans:
Term loan: variable at 1.42% through January 8, 2013, due April 2014	260,000	260,000
Commercial paper refinanced on a long-term basis	465,000
Total long-term debt	6,954,293	5,930,449
Obligations under capital leases	140,212	161,249
Obligation under Rocky Mountain transactions	15,379	14,392
Patronage capital and membership fees	714,489	673,009
Accumulated other comprehensive margin (deficit)	(549)	903
Subtotal	7,823,824	6,780,002
Less: long-term debt and capital leases due within one year	(152,153)	(168,393)
Less: unamortized bond discounts on long-term debt	(3,103)	(3,232)
Total capitalization	7,668,568	6,608,377
Federal Financing Bank | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 2.20% to 8.43% (average rate of 4.41% at December 31, 2013) due in quarterly installments through 2043
Secured Long-term debt:
Debt Instrument Principal Outstanding	2,676,813	2,115,640
National Rural Utilities Cooperative Finance Corporation | First mortgage notes payable to National Rural Utilities Cooperative Finance Corporation at interest rates varying from 3.65% to 4.90% (average rate of 4.31% at December 31, 2013) due in quarterly installments through 2020
Secured Long-term debt:
Debt Instrument Principal Outstanding	5,892	6,659
Public | First mortgage bonds payable: Series 2006 First Mortgage Bonds, 5.534%, due 2031 through 2035
Secured Long-term debt:
Debt Instrument Principal Outstanding	300,000	300,000
Public | First mortgage bonds payable: Series 2007 First Mortgage Bonds, 6.191%, due 2024 through 2031
Secured Long-term debt:
Debt Instrument Principal Outstanding	500,000	500,000
Public | First mortgage bonds payable: Series 2009A First Mortgage Bonds, 6.10%, due 2019
Secured Long-term debt:
Debt Instrument Principal Outstanding	350,000	350,000
Public | First mortgage bonds payable: Series 2009B First Mortgage Bonds, 5.95%, due 2039
Secured Long-term debt:
Debt Instrument Principal Outstanding	400,000	400,000
Public | First mortgage bonds payable: Series 2009 Clean renewable energy bond, 1.81%, due 2024
Secured Long-term debt:
Debt Instrument Principal Outstanding	11,114	12,124
Public | First mortgage bonds payable: Series 2010A First Mortgage Bonds, 5.375% due 2040
Secured Long-term debt:
Debt Instrument Principal Outstanding	450,000	450,000
Public | First mortgage bonds payable: Series 2011A First Mortgage Bonds, 5.25% due 2050
Secured Long-term debt:
Debt Instrument Principal Outstanding	300,000	300,000
Public | First mortgage bonds payable: Series 2012A First Mortgage Bonds, 4.20% due 2042
Secured Long-term debt:
Debt Instrument Principal Outstanding	250,000	250,000
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2003A Burke, Heard, Monroe and 2003B Burke Auction rate bonds, 0.29%, due 2024
Secured Long-term debt:
Debt Instrument Principal Outstanding	95,230	95,230
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2004 Burke and Monroe Auction rate bonds, 0.30%, due 2020
Secured Long-term debt:
Debt Instrument Principal Outstanding	11,525	11,525
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2005 Burke and Monroe Auction rate bonds, 0.25%, due 2040
Secured Long-term debt:
Debt Instrument Principal Outstanding	15,865	15,865
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2008A through 2008C Burke Fixed rate bonds, 5.30% to 5.70%, due 2032 through 2043
Secured Long-term debt:
Debt Instrument Principal Outstanding	255,035	255,035
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2008E Burke Fixed rate bonds, 7.00%, due 2020 through 2023
Secured Long-term debt:
Debt Instrument Principal Outstanding	144,750	144,750
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2008G Burke Term rate bonds, fully redeemed March 2013
Secured Long-term debt:
Debt Instrument Principal Outstanding		22,325
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2009A Heard and Monroe, and 2009B Monroe Weekly rate bonds, 0.04% to 0.05%, due 2030 through 2038
Secured Long-term debt:
Debt Instrument Principal Outstanding	112,055	112,055
Georgia Development Authorities | First mortgage notes issued Series 2010A Burke and Monroe, and 2010B Burke Weekly rate bonds, 0.05% to 0.06%, due 2036 through 2037
Secured Long-term debt:
Debt Instrument Principal Outstanding	133,550	133,550
Georgia Development Authorities | First mortgage notes issued Series 2011A Appling, Burke and Monroe Term rate bonds, fully redeemed March 2013
Secured Long-term debt:
Debt Instrument Principal Outstanding		180,380
Georgia Development Authorities | First mortgage notes issued Series 2012A Monroe Term rate bonds, fully redeemed March 2013
Secured Long-term debt:
Debt Instrument Principal Outstanding		10,055
Georgia Development Authorities | First mortgage notes issued Series 2013A Appling, Burke and Monroe Term rate bonds, 2.40% through April 1, 2020, due 2038 through 2040
Secured Long-term debt:
Debt Instrument Principal Outstanding	212,760
CoBank | ACB notes payable: Transmission first mortgage notes payable: variable at 2.04% to 3.25% through January 30, 2014, due in bimonthly installments through November 1, 2018
Secured Long-term debt:
Debt Instrument Principal Outstanding	890	1,014
CoBank | ACB notes payable: Transmission first mortgage notes payable: variable at 2.04% to 3.25% through January 30, 2014, due in bimonthly installments through September 1, 2019
Secured Long-term debt:
Debt Instrument Principal Outstanding	$ 3,814	$ 4,242