Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net cash provided by operating activities
Net cash provided by operating activities	$ 2,174	$ 1,816
Cash flows provided by investing activities:
Proceeds from maturities and paydowns of trading securities held for investment	13	15
Proceeds from sales of trading securities held for investment	0	49
Proceeds from maturities and paydowns of available-for-sale securities	96	113
Proceeds from sales of available-for-sale securities	50	131
Purchases of loans held for investment	(86,307)	(33,631)
Advances to lenders	(45,248)	(22,991)
Proceeds from disposition of acquired property and preforeclosure sales	1,832	1,965
Net change in federal funds sold and securities purchased under agreements to resell or similar arrangements	5,803	10,688
Other, net	(539)	(124)
Net cash provided by investing activities	47,664	47,446
Cash flows used in financing activities:
Payments of cash dividends on senior preferred stock to Treasury	0	(3,240)
Other, net	(470)	0
Net cash provided by (used in) financing activities	17,463	(46,444)
Net increase in cash, cash equivalents and restricted cash	67,301	2,818
Cash, cash equivalents and restricted cash at beginning of period	61,407	49,423
Cash, cash equivalents and restricted cash at end of period	128,708	52,241
Cash paid during the period for:
Interest	28,867	28,650
Income taxes	0	0
Fannie Mae [Member]
Cash flows provided by investing activities:
Proceeds from repayments of loans acquired as held for investment	2,308	2,786
Proceeds from sales of loans acquired as held for investment of Fannie Mae	0	26
Cash flows used in financing activities:
Proceeds from issuance of debt	254,559	173,122
Payments to redeem debt	(207,818)	(184,222)
Consolidated Trusts [Member]
Cash flows provided by investing activities:
Proceeds from repayments of loans acquired as held for investment	169,656	88,419
Cash flows used in financing activities:
Proceeds from issuance of debt	135,918	64,821
Payments to redeem debt	$ (164,726)	$ (96,925)

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