Statements Of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 47,959	$ (19,532)
Adjustments to reconcile income (loss) to net cash provided by (used in) operating activities:
Premiums and discounts on consolidated obligations, net	(20,182)	(7,703)
Concessions on consolidated obligation bonds	3,100	7,876
Premiums and discounts on investments, net	(1,406)	(1,633)
Premiums and discounts on advances, net	(14,909)	(7,998)
Premiums, discounts and deferred loan costs on mortgage loans, net	2,943	946
Fair value adjustments on hedged assets or liabilities	14,131	8,089
Premises, software and equipment	1,438	2,090
Other	178	88
Provision for credit losses on mortgage loans	909	956
Non-cash interest on mandatorily redeemable capital stock	100	119
Net other-than-temporary impairment losses on held-to-maturity securities	2,454	3,385
Net realized (gain) loss on sale of mortgage loans held for sale	(4,425)	0
Net realized (gain) loss on disposals of premises, software and equipment	(6)	20
Other (gains) losses	69	(67)
Net (gain) loss on trading securities	(3,567)	(48,119)
(Gain) loss due to change in net fair value adjustment on derivative and hedging activities	37,406	72,411
(Increase) decrease in accrued interest receivable	5,921	6,293
Change in net accrued interest included in derivative assets	1,302	(2,091)
(Increase) decrease in other assets	(869)	(1,513)
Increase (decrease) in accrued interest payable	(6,155)	(7,800)
Change in net accrued interest included in derivative liabilities	(1,795)	(2,100)
Increase (decrease) in Affordable Housing Program liability	(3,250)	(3,780)
Increase (decrease) in REFCORP liability	(2,222)	(11,556)
Increase (decrease) in other liabilities	3,031	3,042
Total adjustments	14,196	10,955
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	62,155	(8,577)
CASH FLOWS FROM INVESTING ACTIVITIES:
Net (increase) decrease in interest-bearing deposits	(33,411)	(12,090)
Net (increase) decrease in Federal funds sold	640,000	(2,039,000)
Net (increase) decrease in short-term trading securities	(340,460)	510,884
Proceeds from sale of long-term trading securities	284,445	152,435
Proceeds from maturities of and principal repayments on long-term trading securities	201,376	84,990
Proceeds from maturities of and principal repayments on long-term held-to-maturity securities	968,256	1,659,704
Purchases of long-term held-to-maturity securities	0	(2,375,111)
Principal collected on advances	15,646,928	22,990,689
Advances made	(13,909,090)	(21,639,456)
Proceeds from sale of mortgage loans held for sale	111,444	0
Principal collected on mortgage loans	347,287	246,141
Purchase or origination of mortgage loans	(736,497)	(482,212)
Proceeds from sale of foreclosed assets	3,341	3,754
Principal collected on other loans made	850	795
Proceeds from sale of premises, software and equipment	24	55
Purchases of premises, software and equipment	(553)	(763)
NET CASH PROVIDED BY (USED IN) INVESTING ACTIVITIES	3,183,940	(899,185)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase (decrease) in deposits	525,827	947,981
Net proceeds from issuance of consolidated obligations:
Discount notes	38,461,153	57,112,589
Bonds	4,618,498	9,686,390
Payments for maturing and retired consolidated obligations:
Discount notes	(42,375,720)	(53,092,837)
Bonds	(4,001,900)	(14,122,577)
Net increase (decrease) in other borrowings	(5,000)	(5,000)
Proceeds from financing derivatives	0	142
Net interest payments received (paid) for financing derivatives	(36,028)	(52,646)
Proceeds from issuance of capital stock	45,895	57,219
Payments for repurchase/redemption of capital stock	(2,545)	0
Payments for repurchase of mandatorily redeemable capital stock	(139,224)	(89,458)
Cash dividends paid	(206)	(166)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(2,909,250)	441,637
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	336,845	(466,125)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	260	494,553
CASH AND CASH EQUIVALENTS AT END OF PERIOD	337,105	28,428
Supplemental disclosures:
Interest paid	179,146	197,172
Affordable Housing Program payments	8,685	3,895
REFCORP payments	14,044	11,556
Net transfers of mortgage loans to real estate owned	$ 1,783	$ 3,599