Annual report pursuant to Section 13 and 15(d)

Trading Securities, at Fair Value (Details)

v2.4.0.6
Trading Securities, at Fair Value (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Schedule of Trading Securities and Other Trading Assets [Line Items]      
Trading Securities, Cost $ 997,013    
Trading securities, at fair value 1,002,062 1,003,301  
Trading Securities, Gross Unrealized Gain (Loss) 5,048 3,053  
Proceeds from sales of trading securities 1,001,904 1,222,959 58,516
Trading Securities, Amortized Cost Sold 1,000,207 1,219,636  
Trading Securities, Realized Gain (Loss) 1,697 3,324  
Trading Securities, Change in Unrealized Holding Gain (Loss) 1,996 3,529  
Assets Sold under Agreements to Repurchase, Market Value 14,287,224 7,457,095  
US Treasury Securities [Member]
     
Schedule of Trading Securities and Other Trading Assets [Line Items]      
Assets Sold under Agreements to Repurchase, Market Value $ 1,002,062 $ 1,003,301