Federal National Mortgage Association (FNMA) 10-Q 7 Aug 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014
Entity [Abstract]	'
Entity Registrant Name	'FEDERAL NATIONAL MORTGAGE ASSOCIATION FANNIE MAE
Entity Central Index Key	'0000310522
Current Fiscal Year End Date	'--12-31
Entity Filer Category	'Large Accelerated Filer
Document Type	'10-Q
Document Period End Date	30-Jun-14
Document Fiscal Year Focus	'2014
Document Fiscal Period Focus	'Q2
Amendment Flag	'false
Entity Common Stock, Shares Outstanding	1,158,080,657

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
ASSETS	'	'
Cash and cash equivalents	$20,847	$19,228
Restricted cash (includes $25,401 and $23,982, respectively, related to consolidated trusts)	29,587	28,995
Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700	38,975
Investments in securities:	'	'
Trading, at fair value	26,630	30,768
Available-for-sale, at fair value (includes $561 and $998, respectively, related to consolidated trusts)	34,026	38,171
Total investments in securities	60,656	68,939
Mortgage loans:	'	'
Loans held for sale, at lower of cost or fair value (includes $25 and $31, respectively, related to consolidated trusts)	625	380
Total loans held for investment	3,043,228	3,069,706
Allowance for loan losses	-39,067	-43,846
Total loans held for investment, net of allowance	3,004,161	3,025,860
Total mortgage loans	3,004,786	3,026,240
Accrued interest receivable, net (includes $7,470 and $7,271, respectively, related to consolidated trusts)	8,472	8,319
Acquired property, net	11,560	11,621
Deferred tax assets, net	44,809	47,560
Other assets (includes cash pledged as collateral of $1,821 and $1,590, respectively)	21,400	20,231
Total assets	3,218,817	3,270,108
Liabilities:	'	'
Accrued interest payable (includes $8,213 and $8,276, respectively, related to consolidated trusts)	10,203	10,553
Other liabilities (includes $453 and $488, respectively, related to consolidated trusts)	12,957	15,441
Total liabilities	3,212,705	3,260,517
Commitments and contingencies (Note 17)	0	0
Fannie Mae stockholders’ equity:	'	'
Senior preferred stock, 1,000,000 shares issued and outstanding	117,149	117,149
Preferred stock, 700,000,000 shares are authorized—555,374,922 shares issued and outstanding	19,130	19,130
Common stock, no par value, no maximum authorization—1,308,762,703 shares issued and 1,158,080,657 shares outstanding	687	687
Accumulated deficit	-125,123	-121,227
Accumulated other comprehensive income	1,620	1,203
Treasury stock, at cost, 150,682,046 shares	-7,401	-7,401
Total Fannie Mae stockholders’ equity	6,062	9,541
Noncontrolling interest	50	50
Total equity (See Note 1: Impact of U.S. Government Support for information on our dividend obligation to Treasury)	6,112	9,591
Total liabilities and equity	3,218,817	3,270,108
Fannie Mae [Member]	'	'
Mortgage loans:	'	'
Total loans held for investment	284,609	300,159
Allowance for loan losses	-36,643	-40,521
Total mortgage loans	248,566	259,987
Liabilities:	'	'
Debt (includes $3,432 and $1,308, respectively, of debt of Fannie Mae and $16,420 and $14,976, respectively, of debt of consolidated trusts, at fair value)	477,535	529,434
Consolidated Trusts [Member]	'	'
ASSETS	'	'
Restricted cash (includes $25,401 and $23,982, respectively, related to consolidated trusts)	25,401	23,982
Investments in securities:	'	'
Available-for-sale, at fair value (includes $561 and $998, respectively, related to consolidated trusts)	561	998
Mortgage loans:	'	'
Loans held for sale, at lower of cost or fair value (includes $25 and $31, respectively, related to consolidated trusts)	25	31
Total loans held for investment	2,758,619	2,769,547
Allowance for loan losses	-2,424	-3,325
Total mortgage loans	2,756,220	2,766,253
Accrued interest receivable, net (includes $7,470 and $7,271, respectively, related to consolidated trusts)	7,470	7,271
Liabilities:	'	'
Accrued interest payable (includes $8,213 and $8,276, respectively, related to consolidated trusts)	8,213	8,276
Debt (includes $3,432 and $1,308, respectively, of debt of Fannie Mae and $16,420 and $14,976, respectively, of debt of consolidated trusts, at fair value)	2,712,010	2,705,089
Other liabilities (includes $453 and $488, respectively, related to consolidated trusts)	$453	$488

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, except Share data, unless otherwise specified
ASSETS	'	'
Restricted cash (includes $25,401 and $23,982, respectively, related to consolidated trusts)	$29,587	$28,995
Investments in securities:	'	'
Available-for-sale, at fair value (includes $561 and $998, respectively, related to consolidated trusts)	34,026	38,171
Mortgage loans:	'	'
Loans held for sale, at lower of cost or fair value (includes $25 and $31, respectively, related to consolidated trusts)	625	380
Accrued interest receivable, net (includes $7,470 and $7,271, respectively, related to consolidated trusts)	8,472	8,319
Other assets (includes cash pledged as collateral of $1,821 and $1,590, respectively)	1,821	1,590
Liabilities:	'	'
Accrued interest payable (includes $8,213 and $8,276, respectively, related to consolidated trusts)	10,203	10,553
Other liabilities (includes $453 and $488, respectively, related to consolidated trusts)	12,957	15,441
Fannie Mae stockholders’ equity:	'	'
Senior preferred stock, 1,000,000 shares issued	1,000,000	1,000,000
Senior preferred stock, 1,000,000 shares outstanding	1,000,000	1,000,000
Preferred stock, 700,000,000 shares are authorized	700,000,000	700,000,000
Preferred stock, 555,374,922 shares issued	555,374,922	555,374,922
Preferred stock, 555,374,922 shares outstanding	555,374,922	555,374,922
Common stock, no par value, no maximum authorization—1,308,762,703 shares issued	1,308,762,703	1,308,762,703
Common stock, no par value, no maximum authorization—1,158,080,657 shares outstanding	1,158,080,657	1,158,080,657
Treasury stock, at cost, 150,682,046 shares	150,682,046	150,682,046
Commitments and contingencies (Note 17)	0	0
Fannie Mae [Member]	'	'
Liabilities:	'	'
Debt at fair value	3,432	1,308
Consolidated Trusts [Member]	'	'
ASSETS	'	'
Restricted cash (includes $25,401 and $23,982, respectively, related to consolidated trusts)	25,401	23,982
Investments in securities:	'	'
Available-for-sale, at fair value (includes $561 and $998, respectively, related to consolidated trusts)	561	998
Mortgage loans:	'	'
Loans held for sale, at lower of cost or fair value (includes $25 and $31, respectively, related to consolidated trusts)	25	31
Mortgage loans held for investment, at fair value	15,116	14,268
Loans pledged as collateral that may be sold or repledged included in loans held for investment, at amortized cost	389	442
Accrued interest receivable, net (includes $7,470 and $7,271, respectively, related to consolidated trusts)	7,470	7,271
Liabilities:	'	'
Accrued interest payable (includes $8,213 and $8,276, respectively, related to consolidated trusts)	8,213	8,276
Debt at fair value	16,420	14,976
Other liabilities (includes $453 and $488, respectively, related to consolidated trusts)	$453	$488

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) (USD $)	3 Months Ended				6 Months Ended
In Millions, except Per Share data, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Interest income:	'		'		'		'
Trading securities	$143		$222		$270		$448
Available-for-sale securities	414		651		854		1,324
Mortgage loans (includes $25,533 and $24,847, respectively, for the three months ended and $51,487 and $50,241, respectively, for the six months ended related to consolidated trusts)	28,165		28,056		56,753		57,280
Other	24		49		48		106
Total interest income	28,746		28,978		57,925		59,158
Interest expense:	'		'		'		'
Short-term debt	21		37		41		80
Long-term debt (includes $21,692 and $20,722, respectively, for the three months ended and $43,768 and $41,880, respectively, for the six months ended related to consolidated trusts)	23,821		23,274		48,242		47,107
Total interest expense	23,842		23,311		48,283		47,187
Net interest income	4,904		5,667	[1]	9,642		11,971	[1]
Benefit for credit losses	1,639		5,383	[1]	2,413		6,340	[1]
Net interest income after benefit for credit losses	6,543		11,050	[1]	12,055		18,311	[1]
Investment gains, net	506		290		652		408
Net other-than-temporary impairments	-23		-6	[1]	-74		-15	[1]
Fair value (losses) gains, net	-934		829	[1]	-2,124		1,663	[1]
Debt extinguishment gains, net	38		27	[1]	38		4	[1]
Fee and other income	383		485		4,738		1,053
Non-interest (loss) income	-30		1,625		3,230		3,113
Administrative expenses:	'		'		'		'
Salaries and employee benefits	319		304		644		621
Professional services	275		219		517		442
Occupancy expenses	47		47		97		93
Other administrative expenses	56		56		111		111
Total administrative expenses	697		626	[1]	1,369		1,267	[1]
Foreclosed property income	-214		-332	[1]	-476		-592	[1]
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees	335		233		657		419
Other expenses, net	276		68		407		136
Total expenses	1,094		595		1,957		1,230
Income before federal income taxes	5,419		12,080	[1]	13,328		20,194	[1]
(Provision) benefit for federal income taxes	-1,752		-1,985	[1]	-4,336		48,586	[1],[2]
Net income	3,667		10,095	[1]	8,992		68,780	[1]
Other comprehensive income:	'		'		'		'
Changes in unrealized gains on available-for-sale securities, net of reclassification adjustments and taxes	45		17		417		665
Other	0		149		0		155
Total other comprehensive income	45		166		417		820
Total comprehensive income	3,712		10,261		9,409		69,600
Comprehensive Income Attributable to Noncontrolling Interest	-1		-11		-1		-11
Total comprehensive income attributable to Fannie Mae	3,711		10,250		9,408		69,589
Net income	3,667		10,095	[1]	8,992		68,780	[1]
Net Income Attributable to Noncontrolling Interest	-1		-11	[1]	-1		-11	[1]
Net income attributable to Fannie Mae	3,666		10,084	[1]	8,991		68,769	[1]
Dividends distributed or available for distribution to senior preferred stockholder (Note 11)	-3,712	[3]	-10,243	[3]	-9,404	[3]	-69,611	[3]
Net loss attributable to common stockholders (Note 11)	($46)		($159)		($413)		($842)
Loss per share: basic and diluted	($0.01)		($0.03)		($0.07)		($0.15)
Weighted-average common shares outstanding: basic and diluted	5,762	[4]	5,762	[4]	5,762	[4]	5,762	[4]
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.
[2]	Primarily represented the release of the valuation allowance for our deferred tax assets that generally is directly attributable to each segment based on the nature of the item.
[3]	Represents our dividend payments to Treasury under the terms of the senior preferred stock. Dividends distributed or available for distribution for the three months ended June 30, 2014 (relating to the dividend period for the three months ended September 30, 2014) were calculated based on our net worth as of June 30, 2014 less the applicable capital reserve amount of $2.4 billion and for the six months ended June 30, 2014 we add dividends paid on June 30, 2014 to this amount. Dividends distributed or available for distribution for the three months ended June 30, 2013 (relating to the dividend period for the three months ended September 30, 2013) were calculated based on our net worth as of June 30, 2013 less the applicable capital reserve amount of $3.0 billion and for the six months ended June 30, 2013 we add dividends paid on June 30, 2013 to this amount.
[4]	Includes 4.6 billion of weighted average shares of common stock that would be issued upon the full exercise of the warrant issued to Treasury from the date the warrant was issued through June 30, 2014.

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Operations and Comprehensive Income (Parenthetical) (Unaudited) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Mortgage loans	$28,165	$28,056	$56,753	$57,280
Long-term debt	23,821	23,274	48,242	47,107
Consolidated Trusts [Member]	'	'	'	'
Mortgage loans	25,533	24,847	51,487	50,241
Long-term debt	$21,692	$20,722	$43,768	$41,880

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Net cash provided by operating activities	'	'
Net cash provided by operating activities	$3,420	$4,802
Cash flows provided by investing activities:	'	'
Purchases of trading securities held for investment	0	-3,985
Proceeds from maturities and paydowns of trading securities held for investment	681	1,293
Proceeds from sales of trading securities held for investment	1,188	4,469
Proceeds from maturities and paydowns of available-for-sale securities	3,022	5,861
Proceeds from sales of available-for-sale securities	1,740	2,021
Purchases of loans held for investment	-55,843	-119,122
Net change in restricted cash	-592	13,989
Advances to lenders	-42,545	-76,435
Proceeds from disposition of acquired property and preforeclosure sales	13,471	22,466
Net change in federal funds sold and securities purchased under agreements to resell or similar arrangements	22,275	-5,300
Other, net	-349	170
Net cash provided by investing activities	133,415	269,161
Cash flows used in financing activities:	'	'
Payments of cash dividends on senior preferred stock to Treasury	-12,882	-63,592
Other, net	-7	-2
Net cash used in financing activities	-135,216	-270,362
Net increase in cash and cash equivalents	1,619	3,601
Cash and cash equivalents at beginning of period	19,228	21,117
Cash and cash equivalents at end of period	20,847	24,718
Cash paid during the period for:	'	'
Interest	53,594	55,455
Income Taxes	2,475	1,016
Fannie Mae [Member]	'	'
Cash flows provided by investing activities:	'	'
Proceeds from repayments and sales of loans acquired as held for investment of Fannie Mae	12,840	28,762
Cash flows used in financing activities:	'	'
Proceeds from issuance of debt	165,337	248,901
Payments to redeem debt	-217,988	-261,959
Consolidated Trusts [Member]	'	'
Cash flows provided by investing activities:	'	'
Proceeds from repayments and sales of loans acquired as held for investment of consolidated trusts	177,527	394,972
Cash flows used in financing activities:	'	'
Proceeds from issuance of debt	113,448	235,835
Payments to redeem debt	($183,124)	($429,545)

Summary_of_Significant_Account

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	Organization
	We are a stockholder-owned corporation organized and existing under the Federal National Mortgage Association Charter Act (the “Charter Act” or our “charter”). We are a government-sponsored enterprise (“GSE”) and we are subject to government oversight and regulation. Our regulators include the Federal Housing Finance Agency (“FHFA”), the U.S. Department of Housing and Urban Development (“HUD”), the U.S. Securities and Exchange Commission (“SEC”), and the U.S. Department of the Treasury (“Treasury”). The U.S. government does not guarantee our securities or other obligations.
	Conservatorship
	On September 7, 2008, the Secretary of the Treasury and the Director of FHFA announced several actions taken by Treasury and FHFA regarding Fannie Mae, which included: (1) placing us in conservatorship and (2) the execution of a senior preferred stock purchase agreement by our conservator, on our behalf, and Treasury, pursuant to which we issued to Treasury both senior preferred stock and a warrant to purchase common stock.
	Under the Federal Housing Enterprises Financial Safety and Soundness Act of 1992, as amended by the Federal Housing Finance Regulatory Reform Act of 2008 (together, the “GSE Act”), the conservator immediately succeeded to (1) all rights, titles, powers and privileges of Fannie Mae, and of any stockholder, officer or director of Fannie Mae with respect to Fannie Mae and its assets, and (2) title to the books, records and assets of any other legal custodian of Fannie Mae. The conservator has since delegated specified authorities to our Board of Directors and has delegated to management the authority to conduct our day-to-day operations. The conservator retains the authority to withdraw its delegations at any time.
	The conservatorship has no specified termination date and there continues to be significant uncertainty regarding the future of our company, including how long the company will continue to exist in its current form, the extent of our role in the market, what form we will have, what ownership interest, if any, our current common and preferred stockholders will hold in us after the conservatorship is terminated and whether we will continue to exist following conservatorship. Under the GSE Act, FHFA must place us into receivership if the Director of FHFA makes a written determination that our assets are less than our obligations or if we have not been paying our debts, in either case, for a period of 60 days. In addition, the Director of FHFA may place us in receivership at his discretion at any time for other reasons set forth in the GSE Act, including if we are undercapitalized and have no reasonable prospect of becoming adequately capitalized. Should we be placed into receivership, different assumptions would be required to determine the carrying value of our assets, which could lead to substantially different financial results. We are not aware of any plans of FHFA to significantly change our business model or capital structure in the near term.
	Impact of U.S. Government Support
	We continue to rely on support from Treasury to eliminate any net worth deficits we may experience in the future, which would otherwise trigger our being placed into receivership. Based on consideration of all the relevant conditions and events affecting our operations, including our reliance on the U.S. government, we continue to operate as a going concern and in accordance with our delegation of authority from FHFA.
	We believe that continued federal government support of our business and the financial markets, as well as our status as a GSE, are essential to maintaining our access to debt funding. Changes or perceived changes in federal government support of our business and the financial markets or our status as a GSE could materially and adversely affect our liquidity, financial condition and results of operations.
	Pursuant to the senior preferred stock purchase agreement, Treasury has committed to provide us with funding to help us maintain a positive net worth thereby avoiding the mandatory receivership trigger described above. We have received a total of $116.1 billion from Treasury pursuant to the senior preferred stock purchase agreement as of June 30, 2014. The aggregate liquidation preference of the senior preferred stock, including the initial aggregate liquidation preference of $1.0 billion, was $117.1 billion as of June 30, 2014. As of June 30, 2014, the amount of remaining funding available to us under the senior preferred stock purchase agreement was $117.6 billion.
	Based on the terms of the senior preferred stock, we paid Treasury a dividend of $5.7 billion on June 30, 2014 based on our net worth as of March 31, 2014, and we expect to pay Treasury an additional dividend of $3.7 billion by September 30, 2014.
	Basis of Presentation
	The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the SEC’s instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and note disclosures required by GAAP for complete consolidated financial statements. In the opinion of management, all adjustments of a normal recurring nature considered necessary for a fair presentation have been included. The accompanying condensed consolidated financial statements include our accounts as well as the accounts of other entities in which we have a controlling financial interest. All intercompany accounts and transactions have been eliminated. To conform to our current period presentation, we have reclassified certain amounts reported in our prior periods’ condensed consolidated financial statements. Results for the six months ended June 30, 2014 may not necessarily be indicative of the results for the year ending December 31, 2014. The unaudited interim condensed consolidated financial statements as of and for the six months ended June 30, 2014 should be read in conjunction with our audited consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2013 (“2013 Form 10-K”), filed with the SEC on February 21, 2014.
	Regulatory Capital
	FHFA has announced that, during the conservatorship, our existing statutory and FHFA-directed regulatory capital requirements will not be binding and that FHFA will not issue quarterly capital classifications. We submit capital reports to FHFA, and FHFA monitors our capital levels. The deficit of core capital over statutory minimum capital was $140.0 billion as of June 30, 2014 and $137.3 billion as of December 31, 2013.
	Under the terms of the senior preferred stock, we are required to pay Treasury a dividend each quarter, when, as and if declared, equal to the excess of our net worth as of the end of the preceding quarter over an applicable capital reserve amount. The Director of FHFA directs us to make dividend payments on the senior preferred stock on a quarterly basis. Therefore, we do not expect to eliminate our deficit of core capital over statutory minimum capital.
	Related Parties
	As a result of our issuance to Treasury of the warrant to purchase shares of Fannie Mae common stock equal to 79.9% of the total number of shares of Fannie Mae common stock, we and Treasury are deemed related parties. As of June 30, 2014, Treasury held an investment in our senior preferred stock with an aggregate liquidation preference of $117.1 billion. FHFA’s control of Fannie Mae and Freddie Mac has caused us, FHFA and Freddie Mac to be deemed related parties.
	Our administrative expenses were reduced by $20 million and $24 million for the three months ended June 30, 2014 and 2013, respectively, and $37 million and $50 million for the six months ended June 30, 2014 and 2013, respectively, due to reimbursements from Treasury and Freddie Mac for expenses incurred as program administrator for Treasury’s Home Affordable Modification Program (“HAMP”) and other initiatives under Treasury’s Making Home Affordable Program.
	During the three and six months ended June 30, 2014, we made tax payments of $2.1 billion and $2.5 billion, respectively, to the Internal Revenue Service, a bureau of Treasury. We made tax payments of $1.0 billion during the three and six months ended June 30, 2013.
	Under the temporary credit and liquidity facilities (“TCLF”) program, we had $494 million and $821 million outstanding, which includes principal and interest, of standby credit and liquidity support as of June 30, 2014 and December 31, 2013, respectively. Under the new issue bond (“NIB”) program, we had $4.4 billion and $4.5 billion outstanding of pass-through securities backed by single-family and multifamily housing bonds issued by housing finance agencies (“HFAs”) as of June 30, 2014 and December 31, 2013, respectively. Treasury will bear the initial losses of principal under the TCLF program and the NIB program up to 35% of the total original principal on a combined program-wide basis, and thereafter we will bear the losses of principal that are attributable to the TCLF and the securities we have issued. Treasury will also bear any losses of unpaid interest under the two programs. As of June 30, 2014, there had been no losses of principal or interest under the TCLF program or the NIB program.
	The fee revenue and expense related to the Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) are recorded in “Mortgage loans interest income” and “TCCA fees,” respectively, in our condensed consolidated statements of operations and comprehensive income. We recognized $335 million and $233 million in TCCA fees during the three months ended June 30, 2014 and 2013, respectively, and $657 million and $419 million for the six months ended June 30, 2014 and 2013, respectively, of which $335 million have not been remitted to Treasury as of June 30, 2014. During the three months ended June 30, 2014, we remitted TCCA-related guaranty fees of $322 million to Treasury for our obligations as of March 31, 2014.
	As of June 30, 2014 and December 31, 2013, we held Freddie Mac mortgage-related securities with a fair value of $8.0 billion and $8.7 billion, respectively. We recognized interest income on these securities held by us of $73 million and $101 million for the three months ended June 30, 2014 and 2013, respectively, and $151 million and $212 million for the six months ended June 30, 2014 and 2013, respectively. In addition, Freddie Mac may be an investor in variable interest entities that we have consolidated, and we may be an investor in variable interest entities that Freddie Mac has consolidated.
	The Housing and Economic Recovery Act of 2008 authorizes FHFA to establish an annual assessment for regulated entities, including Fannie Mae, which is payable on a semi-annual basis (April and October), for FHFA’s costs and expenses, as well as to maintain FHFA’s working capital. We recognized FHFA assessment fees, which are recorded in “Administrative expenses” in our condensed consolidated statements of operations and comprehensive income, of $26 million and $27 million for the three months ended June 30, 2014 and 2013, respectively, and $54 million and $55 million for the six months ended June 30, 2014 and 2013, respectively.
	In March 2013, FHFA announced that a new business entity would be established by Fannie Mae and Freddie Mac that would be separate from the two companies in order to further the goal of building a common securitization platform that would function like a market utility. In October 2013, FHFA announced that the new joint venture by Fannie Mae and Freddie Mac, Common Securitization Solutions, LLC, had been established and that office space for the new entity had been secured. In connection with the entity’s establishment, we entered into a Limited Liability Company Agreement with Freddie Mac in October 2013 and anticipate entering into additional agreements relating to the new joint venture in the future. No other transactions outside of normal business activities occurred between us and Freddie Mac during the six months ended June 30, 2014 or 2013.
	Use of Estimates
	Preparing condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect our reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities as of the dates of our condensed consolidated financial statements, as well as our reported amounts of revenues and expenses during the reporting periods. Management has made significant estimates in a variety of areas including, but not limited to, valuation of certain financial instruments and other assets and liabilities, recoverability of our deferred tax assets, allowance for loan losses and reserve for guaranty losses, and other-than-temporary impairment of investment securities. Actual results could be different from these estimates.
	Fee and Other Income
	Fee and other income includes transaction fees, technology fees, multifamily fees and other miscellaneous income. During the six months ended June 30, 2014, we recognized $4.2 billion in “Fee and other income” in our condensed consolidated statement of operations and comprehensive income resulting from settlement agreements resolving certain lawsuits relating to private-label securities sold to us.
	Statement of Cash Flows
	We classify cash flows related to trading securities based on their nature and purpose. Effective January 1, 2014, all cash flows related to trading securities purchased after December 31, 2013 are classified as operating activities as we do not intend to hold these securities for investment.
	Adoption of New Accounting Guidance
	In January 2014, the FASB issued guidance clarifying when a creditor is considered to have received physical possession of residential real estate property collateralized by a consumer mortgage loan in order to reduce diversity in practice for when a creditor derecognizes the loan receivable and recognizes the real estate property. The guidance also requires interim and annual disclosure of the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The new guidance is effective for us on January 1, 2015. We do not expect that the adoption of this guidance will have a material impact on our consolidated financial statements.
	In May 2014, the FASB issued their final standard on revenue from contracts with customers. The standard outlines a single model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance in an effort to remove inconsistencies in revenue recognition standards, improve comparability across entities, provide enhanced disclosures related to revenue recognition and to converge with the jointly issued International Financial Reporting Standards revenue recognition guidance. The following contracts with customers are excluded from the scope of the new standard and will continue to be accounted for under existing guidance: leases, insurance, financial instruments (e.g., receivables, investments, liabilities, debt and derivatives) and guarantees. The new guidance is effective for us on January 1, 2017. We are evaluating this guidance and have not determined the impact, if any, on our consolidated financial statements of adopting this guidance.

Consolidations_and_Transfers_o

Consolidations and Transfers of Financial Assets	6 Months Ended
	Jun. 30, 2014
Consolidations and Transfers of Financial Assets [Abstract]	'
Consolidations and Transfers of Financial Assets	'
	Consolidations and Transfers of Financial Assets
	We have interests in various entities that are considered to be variable interest entities (“VIEs”). The primary types of entities are securitization trusts guaranteed by us via lender swap and portfolio securitization transactions, mortgage and asset-backed trusts that were not created by us, as well as housing partnerships that are established to finance the acquisition, construction, development or rehabilitation of affordable multifamily and single-family housing. These interests include investments in securities issued by VIEs, such as Fannie Mae MBS created pursuant to our securitization transactions and our guaranty to the entity. We consolidate the substantial majority of our single-class securitization trusts because our role as guarantor and master servicer provides us with the power to direct matters (primarily the servicing of mortgage loans) that impact the credit risk to which we are exposed. In contrast, we do not consolidate single-class securitization trusts when other organizations have the power to direct these activities.
	We continually assess whether we are the primary beneficiary of the VIEs with which we are involved and therefore may consolidate or deconsolidate a VIE through the duration of our involvement. Examples of certain events that may change whether or not we consolidate the VIE include a change in the design of the entity or a change in our ownership in the entity such that we no longer hold substantially all of the certificates issued by a multi-class securitization trust. As of June 30, 2014, we consolidated certain VIEs that were not consolidated as of December 31, 2013. As a result of consolidating these entities, which had combined total assets of $381 million in unpaid principal balance as of June 30, 2014, we derecognized our investment in these entities and recognized the assets and liabilities of the consolidated entities at fair value. As of June 30, 2014, we also deconsolidated certain VIEs that were consolidated as of December 31, 2013. As a result of deconsolidating these entities, which had combined total assets of $316 million in unpaid principal balance as of December 31, 2013, we derecognized the assets and liabilities of the entities and recognized at fair value our retained interests as securities in our condensed consolidated balance sheets.
	Unconsolidated VIEs
	We do not consolidate VIEs when we are not deemed to be the primary beneficiary. Our unconsolidated VIEs include securitization trusts and limited partnerships. The following table displays the carrying amount and classification of our assets and liabilities that relate to our involvement with unconsolidated mortgage-backed trusts as of June 30, 2014 and December 31, 2013, as well as our maximum exposure to loss and the total assets of these unconsolidated mortgage-backed trusts.
		As of
		June 30, 2014					December 31, 2013
		(Dollars in millions)
	Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts:
	Assets:
	Trading securities:
	Fannie Mae securities		$	5,514				$	5,660
	Non-Fannie Mae securities		7,834					8,559
	Total trading securities		13,348					14,219
	Available-for-sale securities:
	Fannie Mae securities		5,462					5,866
	Non-Fannie Mae securities		24,981					27,441
	Total available-for-sale securities		30,443					33,307
	Other assets		118					119
	Other liabilities		(1,600		)			(1,668		)
	Net carrying amount		$	42,309				$	45,977
	Maximum exposure to loss(1)		$	49,596				$	54,148
	Total assets of unconsolidated mortgage-backed trusts		$	284,852				$	313,202
	__________
	(1)	Our maximum exposure to loss generally represents the greater of our recorded investment in the entity or the unpaid principal balance of the assets covered by our guaranty. However, our securities issued by Fannie Mae multi-class resecuritization trusts that are not consolidated do not give rise to any additional exposure to loss as we already consolidate the underlying collateral.
	Additionally, our maximum exposure to loss related to our involvement with limited partnership investments was $20 million and $14 million as of June 30, 2014 and December 31, 2013, respectively. The total assets of these unconsolidated limited partnership investments were $6.3 billion and $6.8 billion as of June 30, 2014 and December 31, 2013, respectively.
	Transfers of Financial Assets
	We issue Fannie Mae MBS through portfolio securitization transactions by transferring pools of mortgage loans or mortgage-related securities to one or more trusts or special purpose entities. We are considered to be the transferor when we transfer assets from our own retained mortgage portfolio in a portfolio securitization transaction. For the three months ended June 30, 2014 and 2013, the unpaid principal balance of portfolio securitizations was $36.4 billion and $62.5 billion, respectively. For the six months ended June 30, 2014 and 2013, the unpaid principal balance of portfolio securitizations was $68.9 billion and $131.8 billion, respectively.
	The following table displays some key characteristics of the securities retained in unconsolidated portfolio securitization trusts as of June 30, 2014 and December 31, 2013.
		Fannie Mae Single-class MBS & Fannie Megas				REMICS & SMBS(1)
		(Dollars in millions)
	As of June 30, 2014
	Unpaid principal balance	$	314			$	6,664
	Fair value	350				7,878
	Weighted-average coupon	6.19			%	5.3			%
	Weighted-average loan age	7.9			years	5.7			years
	Weighted-average maturity	21			years	11.1			years
	As of December 31, 2013
	Unpaid principal balance	$	349			$	6,899
	Fair value	383				7,959
	Weighted-average coupon	6.21			%	5.36			%
	Weighted-average loan age	7.4			years	5.4			years
	Weighted-average maturity	21.5			years	12.6			years
	__________
	(1)	Consists of real estate mortgage investment conduits (“REMICs”) and stripped mortgage-backed securities (“SMBS”).
	For the three months ended June 30, 2014 and 2013, the principal and interest received on retained interests was $373 million and $469 million, respectively. For the six months ended June 30, 2014 and 2013, the principal and interest received on retained interests was $713 million and $928 million, respectively.
	Managed Loans
	Managed loans are on-balance sheet mortgage loans, as well as mortgage loans that we have securitized in unconsolidated portfolio securitization trusts. The unpaid principal balance of securitized loans in unconsolidated portfolio securitization trusts, which are primarily loans that are guaranteed or insured, in whole or in part, by the U.S. government, was $2.0 billion and $2.1 billion as of June 30, 2014 and December 31, 2013, respectively. For information on our on-balance sheet mortgage loans, see “Note 3, Mortgage Loans.”
	Qualifying Sales of Portfolio Securitizations
	We consolidate the substantial majority of our single-class MBS trusts; therefore, these portfolio securitization transactions do not qualify for sale treatment. The assets and liabilities of consolidated trusts created via portfolio securitization transactions that do not qualify as sales are reported in our condensed consolidated balance sheets.
	We recognize assets obtained and liabilities incurred in qualifying sales of portfolio securitizations at fair value. There were no proceeds from the initial sale of securities from portfolio securitizations for the three and six months ended June 30, 2014. Proceeds from the initial sale of securities from portfolio securitizations were $75 million and $251 million for the three and six months ended June 30, 2013, respectively. Our continuing involvement in the form of guaranty assets and guaranty liabilities with assets that were transferred into unconsolidated trusts is not material to our condensed consolidated financial statements.

Mortgage_Loans

Mortgage Loans	6 Months Ended
	Jun. 30, 2014
Mortgage Loans on Real Estate [Abstract]	'
Mortgage Loans	'
	Mortgage Loans
	The following table displays our mortgage loans as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014																		December 31, 2013
		Of Fannie Mae						Of Consolidated Trusts						Total						Of Fannie Mae						Of Consolidated Trusts						Total
		(Dollars in millions)
	Single-family		$	268,114					$	2,561,871					$	2,829,985					$	276,644					$	2,579,024					$	2,855,668
	Multifamily		30,259						151,036						181,295						37,642						146,249						183,891
	Total unpaid principal balance of mortgage loans		298,373						2,712,907						3,011,280						314,286						2,725,273						3,039,559
	Cost basis and fair value adjustments, net		(13,164		)				45,737						32,573						(13,778		)				44,305						30,527
	Allowance for loan losses for loans held for investment		(36,643		)				(2,424		)				(39,067		)				(40,521		)				(3,325		)				(43,846		)
	Total mortgage loans		$	248,566					$	2,756,220					$	3,004,786					$	259,987					$	2,766,253					$	3,026,240
	During the three months ended June 30, 2014 and 2013, we redesignated loans with a carrying value of $19 million and $74 million, respectively, from held for investment (“HFI”) to held for sale (“HFS”). During the six months ended June 30, 2014 and 2013, we redesignated loans with a carrying value of $2.2 billion and $74 million, respectively, from HFI to HFS. We sold loans with an unpaid principal balance of $862 million and $1.9 billion during the three and six months ended June 30, 2014, respectively.
	Nonaccrual Loans
	We discontinue accruing interest on loans when we believe collectibility of principal or interest is not reasonably assured, which for single-family loans we have determined, based on our historical experience, to be when the loan becomes two months or more past due according to its contractual terms. We generally place multifamily loans on nonaccrual status when the loan is deemed to be individually impaired, unless the loan is well secured such that collectibility of principal and accrued interest is reasonably assured.
	When a loan is placed on nonaccrual status, interest previously accrued but not collected becomes part of our recorded investment in the loan and is reviewed for impairment in connection with our allowance for loan losses process. For single-family loans, we recognize interest income for loans on nonaccrual status when cash is received. For multifamily loans on nonaccrual status, we apply any payment received on a cost recovery basis to reduce principal on the mortgage loan.
	We return a single-family loan to accrual status at the point that the borrower has made sufficient payments to reduce their delinquency below our nonaccrual threshold. For modified single-family loans, the loan is not returned to accrual status until the borrower successfully makes all required payments during the trial period (generally three to four months) and the modification is made permanent. We generally return a multifamily loan to accrual status when the borrower cures the delinquency of the loan or we otherwise determine that the loan is well secured such that collectibility is reasonably assured.
	Aging Analysis
	The following tables display an aging analysis of the total recorded investment in our HFI mortgage loans, excluding loans for which we have elected the fair value option, by portfolio segment and class as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014(1)
		30 - 59 Days						60 - 89 Days Delinquent						Seriously Delinquent(2)						Total Delinquent						Current				Total				Recorded Investment in Loans 90 Days or More Delinquent and Accruing Interest					Recorded Investment in Nonaccrual Loans
		Delinquent
		(Dollars in millions)
	Single-family:
	Primary(3)		$	29,122					$	8,323					$	41,458					$	78,903				$	2,560,063			$	2,638,966				$	57			$	49,689
	Government(4)		63						24						330						417					46,586				47,003					330				—
	Alt-A		4,227						1,469						13,220						18,916					100,616				119,532					9				14,677
	Other(5)		1,678						562						4,387						6,627					42,225				48,852					18				4,899
	Total single-family		35,090						10,378						59,395						104,863					2,749,490				2,854,353					414				69,265
	Multifamily(6)		59						N/A						172						231					182,715				182,946					—				1,617
	Total		$	35,149					$	10,378					$	59,567					$	105,094				$	2,932,205			$	3,037,299				$	414			$	70,882
		As of December 31, 2013(1)
		30 - 59 Days						60 - 89 Days Delinquent						Seriously Delinquent(2)						Total Delinquent						Current				Total				Recorded Investment in Loans 90 Days or More Delinquent and Accruing Interest					Recorded Investment in Nonaccrual Loans
		Delinquent
		(Dollars in millions)
	Single-family:
	Primary(3)		$	32,371					$	9,755					$	48,345					$	90,471				$	2,558,826			$	2,649,297				$	81			$	57,973
	Government(4)		66						32						346						444					48,150				48,594					346				—
	Alt-A		4,748						1,692						15,425						21,865					105,644				127,509					11				17,102
	Other(5)		1,940						659						5,404						8,003					45,288				53,291					22				5,999
	Total single-family		39,125						12,138						69,520						120,783					2,757,908				2,878,691					460				81,074
	Multifamily(6)		59						N/A						186						245					185,733				185,978					—				2,209
	Total		$	39,184					$	12,138					$	69,706					$	121,028				$	2,943,641			$	3,064,669				$	460			$	83,283
	__________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
	(2)	Single-family seriously delinquent loans are loans that are 90 days or more past due or in the foreclosure process. Multifamily seriously delinquent loans are loans that are 60 days or more past due.
	(3)	Consists of mortgage loans that are not included in other loan classes.
	(4)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A. Primarily consists of reverse mortgages which, due to their nature, are not aged and are included in the current column.
	(5)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
	(6)	Multifamily loans 60-89 days delinquent are included in the seriously delinquent column.
	Credit Quality Indicators
	The following table displays the total recorded investment in our single-family HFI loans, excluding loans for which we have elected the fair value option, by class and credit quality indicator as of June 30, 2014 and December 31, 2013. The single-family credit quality indicator is based on available data through the end of each period presented.
		As of
		June 30, 2014(1)(2)														December 31, 2013(1)(2)
		Primary(3)				Alt-A				Other(4)						Primary(3)				Alt-A				Other(4)
		(Dollars in millions)
	Estimated mark-to-market loan-to-value ratio:(5)
	Less than or equal to 80%	$	2,135,261			$	62,455				$	24,320				$	2,073,079			$	61,670				$	24,112
	Greater than 80%  and less than or equal to 90%	256,754				15,978					6,494					276,011				16,794					6,947
	Greater than 90%  and less than or equal to 100%	131,666				13,366					5,760					153,474				14,709					6,402
	Greater than 100% and less than or equal to 110%	49,148				9,783					4,327					59,630				11,006					5,146
	Greater than 110%  and less than or equal to 120%	27,280				6,651					3,069					33,954				7,742					3,691
	Greater than 120%  and less than or equal to 125%	8,908				2,418					1,054					11,256				2,951					1,406
Greater than 125%	29,949				8,881					3,828					41,893				12,637					5,587
Total	$	2,638,966			$	119,532				$	48,852				$	2,649,297			$	127,509				$	53,291
__________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
(2)	Excludes $47.0 billion and $48.6 billion as of June 30, 2014 and December 31, 2013, respectively, of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A loans. The segment class is primarily reverse mortgages for which we do not calculate an estimated mark-to-market LTV ratio.
(3)	Consists of mortgage loans that are not included in other loan classes.
(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
(5)	The aggregate estimated mark-to-market LTV ratio is based on the unpaid principal balance of the loan as of the end of each reported period divided by the estimated current value of the property, which we calculate using an internal valuation model that estimates periodic changes in home value.
The following table displays the total recorded investment in our multifamily HFI loans, excluding loans for which we have elected the fair value option, by credit quality indicator as of June 30, 2014 and December 31, 2013. The multifamily credit quality indicator is based on available data through the end of each period presented.
	As of
	June 30,						December 31,
	2014(1)						2013(1)
	(Dollars in millions)
Credit risk profile by internally assigned grade:(2)
Pass		$	174,656					$	176,528
Special Mention		2,523						2,234
Substandard		5,346						6,758
Doubtful		421						458
Total		$	182,946					$	185,978
_________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
(2)	Pass (loan is current and adequately protected by the current financial strength and debt service capacity of the borrower); special mention (loan with signs of potential weakness); substandard (loan with a well defined weakness that jeopardizes timely full repayment); and doubtful (loan with a weakness that makes collection or liquidation in full highly questionable and improbable based on existing conditions and values).
Individually Impaired Loans
Individually impaired loans include troubled debt restructurings (“TDRs”), acquired credit-impaired loans and multifamily loans that we have assessed as probable that we will not collect all contractual amounts due, regardless of whether we are currently accruing interest. The following tables display the total unpaid principal balance, recorded investment and related allowance as of June 30, 2014 and December 31, 2013, and interest income recognized and average recorded investment for the three and six months ended June 30, 2014 and 2013, for individually impaired loans.
	As of
	June 30, 2014																				December 31, 2013
	Unpaid Principal Balance						Total Recorded Investment (1)						Related Allowance for Loan Losses				Related Allowance for Accrued Interest Receivable				Unpaid Principal Balance						Total Recorded Investment (1)						Related Allowance for Loan Losses			Related Allowance for Accrued Interest Receivable
	(Dollars in millions)
Individually impaired loans:
With related allowance recorded:
Single-family:
Primary(2)		$	128,363					$	122,031				$	22,370			$	363				$	130,080					$	123,631				$	24,145		$	430
Government(3)		279						283					42				12					213						210					35			5
Alt-A		36,695						33,817					8,673				160					37,356						34,479					9,364			187
Other(4)		15,323						14,541					3,539				46					15,789						15,023					3,879			56
Total single-family		180,660						170,672					34,624				581					183,438						173,343					37,423			678
Multifamily		1,715						1,729					249				8					2,257						2,276					306			10
Total individually impaired loans with related allowance recorded		182,375						172,401					34,873				589					185,695						175,619					37,729			688
With no related allowance recorded:(5)
Single-family:
Primary(2)		15,531						14,013					—				—					14,076						12,305					—			—
Government(3)		61						56					—				—					120						120					—			—
Alt-A		3,476						2,705					—				—					3,290						2,428					—			—
Other(4)		1,099						949					—				—					1,039						868					—			—
Total single-family		20,167						17,723					—				—					18,525						15,721					—			—
Multifamily		1,613						1,622					—				—					1,927						1,939					—			—
Total individually impaired loans with no related allowance recorded		21,780						19,345					—				—					20,452						17,660					—			—
Total individually impaired loans(6)		$	204,155					$	191,746				$	34,873			$	589				$	206,147					$	193,279				$	37,729		$	688
	For the Three Months Ended June 30,
	2014																		2013
	Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis						Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis
	(Dollars in millions)
Individually impaired loans:
With related allowance recorded:
Single-family:
Primary(2)		$	122,791					$	1,093					$	121					$	125,689					$	1,093					$	152
Government(3)		281						3						—						214						2						—
Alt-A		34,029						267						22						35,376						275						35
Other(4)		14,669						102						9						15,700						108						15
Total single-family		171,770						1,465						152						176,979						1,478						202
Multifamily		1,813						23						—						2,704						36						1
Total individually impaired loans with related allowance recorded		173,583						1,488						152						179,683						1,514						203
With no related allowance recorded:(5)
Single-family:
Primary(2)		13,413						205						53						10,301						283						57
Government(3)		56						2						—						112						2						—
Alt-A		2,636						43						10						1,972						55						12
Other(4)		927						13						3						661						23						5
Total single-family		17,032						263						66						13,046						363						74
Multifamily		1,668						20						—						1,666						25						—
Total individually impaired loans with no related allowance recorded		18,700						283						66						14,712						388						74
Total individually impaired loans(6)		$	192,283					$	1,771					$	218					$	194,395					$	1,902					$	277
	For the Six Months Ended June 30,
	2014																		2013
	Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis						Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis
	(Dollars in millions)
Individually impaired loans:
With related allowance recorded:
Single-family:
Primary(2)		$	123,066					$	2,187					$	261					$	125,663					$	2,195					$	325
Government(3)		257						6						—						211						5						—
Alt-A		34,178						537						50						35,422						552						74
Other(4)		14,787						205						20						15,830						217						29
Total single-family		172,288						2,935						331						177,126						2,969						428
Multifamily		1,967						46						—						2,628						67						1
Total individually impaired loans with related allowance recorded		174,255						2,981						331						179,754						3,036						429
With no related allowance recorded:(5)
Single-family:
Primary(2)		13,055						390						101						10,688						924						116
Government(3)		76						3						—						110						4						—
Alt-A		2,576						84						20						2,049						230						22
Other(4)		910						24						5						671						86						10
Total single-family		16,617						501						126						13,518						1,244						148
Multifamily		1,758						40						—						1,800						47						1
Total individually impaired loans with no related allowance recorded		18,375						541						126						15,318						1,291						149
Total individually impaired loans(6)		$	192,630					$	3,522					$	457					$	195,072					$	4,327					$	578
__________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
(2)	Consists of mortgage loans that are not included in other loan classes.
(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
(5)	The discounted cash flows or collateral value equals or exceeds the carrying value of the loan and, as such, no valuation allowance is required.
(6)	Includes single-family loans restructured in a TDR with a recorded investment of $187.1 billion and $187.6 billion as of June 30, 2014 and December 31, 2013, respectively. Includes multifamily loans restructured in a TDR with a recorded investment of $880 million and $911 million as of June 30, 2014 and December 31, 2013, respectively.
(7)	Total single-family interest income recognized of $1.7 billion and $1.8 billion for the three months ended June 30, 2014 and 2013, respectively, consists of $1.4 billion of contractual interest for both periods and $285 million and $410 million of effective yield adjustments, respectively. Total single-family interest income recognized of $3.4 billion and $4.2 billion for the six months ended June 30, 2014 and 2013, respectively, consists of $2.9 billion of contractual interest for both periods and $560 million and $1.3 billion of effective yield adjustments, respectively.
Troubled Debt Restructurings
A modification to the contractual terms of a loan that results in granting a concession to a borrower experiencing financial difficulties is considered a TDR. In addition to formal loan modifications, we also engage in other loss mitigation activities with troubled borrowers, which include repayment plans and forbearance arrangements, both of which represent informal agreements with the borrower that do not result in the legal modification of the loan’s contractual terms. We account for these informal restructurings as a TDR if we defer more than three missed payments. We also classify as TDRs loans to certain borrowers who have received bankruptcy relief.
The substantial majority of the loan modifications we complete result in term extensions, interest rate reductions or a combination of both. During the three months ended June 30, 2014 and 2013, the average term extension of a single-family modified loan was 162 months and 154 months, respectively, and the average interest rate reduction was 0.99 and 1.70 percentage points, respectively. During the six months ended June 30, 2014 and 2013, the average term extension of a single-family modified loan was 161 months and 151 months, respectively, and the average interest rate reduction was 1.12 and 1.76 percentage points, respectively.
The following table displays the number of loans and recorded investment in loans restructured in a TDR for the three and six months ended June 30, 2014 and 2013.
	For the Three Months Ended June 30,
	2014											2013
	Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
	(Dollars in millions)
Single-family:
Primary(2)		24,932					$	3,564					31,304					$	4,833
Government(3)		111					13						90					10
Alt-A		3,660					614						5,175					947
Other(4)		872					179						1,641					370
Total single-family		29,575					4,370						38,210					6,160
Multifamily		3					4						17					135
Total troubled debt restructurings		29,578					$	4,374					38,227					$	6,295
	For the Six Months Ended June 30,
	2014											2013
	Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
	(Dollars in millions)
Single-family:
Primary(2)		53,774					$	7,674					69,555					$	10,477
Government(3)		173					21						180					21
Alt-A		8,056					1,354						12,285					2,170
Other(4)		1,910					398						3,698					822
Total single-family		63,913					9,447						85,718					13,490
Multifamily		9					38						25					168
Total troubled debt restructurings		63,922					$	9,485					85,743					$	13,658
__________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Based on the nature of our modification programs, which do not include principal or past-due interest forgiveness, there is not a material difference between the recorded investment in our loans pre- and post- modification, therefore amounts represent recorded investment post-modification.
(2)	Consists of mortgage loans that are not included in other loan classes.
(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
The following table displays the number of loans and recorded investment in loans that had a payment default for the three and six months ended June 30, 2014 and 2013 and were restructured in a TDR in the twelve months prior to the payment default. For purposes of this disclosure, we define loans that had a payment default as: single-family and multifamily loans with completed TDRs that liquidated during the period, either through foreclosure, deed-in-lieu of foreclosure or a short sale; single-family loans with completed modifications that are two or more months delinquent during the period; or multifamily loans with completed modifications that are one or more months delinquent during the period.
	For the Three Months Ended June 30,
	2014											2013
	Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
	(Dollars in millions)
Single-family:
Primary(2)		8,190					$	1,251					11,320					$	1,749
Government(3)		18					1						31					4
Alt-A		1,396					252						2,584					466
Other(4)		420					89						852					195
Total single-family		10,024					1,593						14,787					2,414
Multifamily		1					3						3					5
Total TDRs that subsequently defaulted		10,025					$	1,596					14,790					$	2,419
	For the Six Months Ended June 30,
	2014											2013
	Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
	(Dollars in millions)
Single-family:
Primary(2)		16,788					$	2,561					23,380					$	3,616
Government(3)		36					3						60					8
Alt-A		2,840					512						5,256					950
Other(4)		924					204						1,675					380
Total single-family		20,588					3,280						30,371					4,954
Multifamily		5					17						6					20
Total TDRs that subsequently defaulted		20,593					$	3,297					30,377					$	4,974
__________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Represents our recorded investment in the loan at time of payment default.
(2)	Consists of mortgage loans that are not included in other loan classes.
(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.

Allowance_for_Loan_Losses

Allowance for Loan Losses	6 Months Ended
	Jun. 30, 2014
Loans and Leases Receivable, Allowance [Abstract]	'
Allowance for Loan Losses	'
	Allowance for Loan Losses
	Our allowance for loan losses is a valuation allowance that reflects an estimate of incurred credit losses related to our recorded investment in both single-family and multifamily HFI loans. This population includes both HFI loans held by Fannie Mae and by consolidated Fannie Mae MBS trusts. When calculating our allowance for loan losses, we consider only our net recorded investment in the loan at the balance sheet date, which includes the loan’s unpaid principal balance and accrued interest recognized while the loan was on accrual status and any applicable cost basis adjustments. We record charge-offs as a reduction to the allowance for loan losses when losses are confirmed through the receipt of assets in full satisfaction of a loan, such as the underlying collateral upon foreclosure or cash upon completion of a short sale.
	We aggregate single-family HFI loans that are not individually impaired based on similar risk characteristics, for purposes of estimating incurred credit losses and establishing a collective single-family loss reserve using an econometric model that derives an overall loss reserve estimate. We base our allowance methodology on historical events and trends, such as loss severity (in event of default), default rates, and recoveries from mortgage insurance contracts and other credit enhancements. In addition, management performs a review of the observable data used in its estimate to ensure it is representative of prevailing economic conditions and other events existing as of the balance sheet date.
	Individually impaired single-family loans currently include those restructured in a TDR and acquired credit-impaired loans. When a loan has been restructured, we measure impairment using a cash flow analysis discounted at the loan’s original effective interest rate. However, if we expect to recover our recorded investment in an individually impaired loan through probable foreclosure of the underlying collateral, we measure impairment based on the fair value of the collateral, reduced by estimated disposal costs and adjusted for estimated proceeds from mortgage, flood, or hazard insurance and other credit enhancements.
	We identify multifamily loans for evaluation for impairment through a credit risk assessment process. If we determine that a multifamily loan is individually impaired, we generally measure impairment on that loan based on the fair value of the underlying collateral less estimated costs to sell the property. If we determine that an individual loan that was specifically evaluated for impairment is not individually impaired, we include the loan as part of a pool of loans with similar characteristics that are evaluated collectively for incurred losses.
	The following table displays changes in single-family, multifamily and total allowance for loan losses for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,
		2014										2013
		Of Fannie Mae			Of Consolidated Trusts				Total			Of Fannie Mae			Of Consolidated Trusts				Total
		(Dollars in millions)
	Single-family allowance for loan losses:
	Beginning balance	$	38,746			$	2,702		$	41,448		$	48,967			$	6,534		$	55,501
	Benefit for loan losses(1)	(1,288		)		(240		)	(1,528		)	(4,098		)		(1,330		)	(5,428		)
	Charge-offs(2)	(1,861		)		(42		)	(1,903		)	(2,015		)		(137		)	(2,152		)
	Recoveries	311				147			458			466				106			572
	Transfers(3)	337				(337		)	—			768				(768		)	—
	Other(4)	155				13			168			244				33			277
	Ending balance	$	36,400			$	2,243		$	38,643		$	44,332			$	4,438		$	48,770
	Multifamily allowance for loan losses:
	Beginning balance	$	258			$	205		$	463		$	586			$	374		$	960
	(Benefit) provision for loan losses(1)	(8		)		(22		)	(30		)	(36		)		15			(21		)
	Charge-offs(2)	(8		)		—			(8		)	(66		)		—			(66		)
	Transfers(3)	2				(2		)	—			8				(8		)	—
	Other(4)	(1		)		—			(1		)	1				(1		)	—
	Ending balance	$	243			$	181		$	424		$	493			$	380		$	873
	Total allowance for loan losses:
	Beginning balance	$	39,004			$	2,907		$	41,911		$	49,553			$	6,908		$	56,461
	Benefit for loan losses(1)	(1,296		)		(262		)	(1,558		)	(4,134		)		(1,315		)	(5,449		)
	Charge-offs(2)(5)	(1,869		)		(42		)	(1,911		)	(2,081		)		(137		)	(2,218		)
	Recoveries	311				147			458			466				106			572
	Transfers(3)	339				(339		)	—			776				(776		)	—
	Other(4)	154				13			167			245				32			277
	Ending balance	$	36,643			$	2,424		$	39,067		$	44,825			$	4,818		$	49,643
		For the Six Months Ended June 30,
		2014										2013
		Of Fannie Mae			Of Consolidated Trusts				Total			Of Fannie Mae			Of Consolidated Trusts				Total
		(Dollars in millions)
	Single-family allowance for loan losses:
	Beginning balance	$	40,202			$	3,105		$	43,307		$	49,848			$	7,839		$	57,687
	Benefit for loan losses(1)	(2,170		)		(202		)	(2,372		)	(4,534		)		(1,733		)	(6,267		)
	Charge-offs(2)	(3,308		)		(143		)	(3,451		)	(4,685		)		(186		)	(4,871		)
	Recoveries	631				218			849			1,493				351			1,844
	Transfers(3)	757				(757		)	—			1,891				(1,891		)	—
	Other(4)	288				22			310			319				58			377
	Ending balance	$	36,400			$	2,243		$	38,643		$	44,332			$	4,438		$	48,770
	Multifamily allowance for loan losses:
	Beginning balance	$	319			$	220		$	539		$	671			$	437		$	1,108
	Benefit for loan losses(1)	(20		)		(38		)	(58		)	(127		)		(39		)	(166		)
	Charge-offs(2)	(59		)		—			(59		)	(67		)		—			(67		)
	Transfers(3)	2				(2		)	—			17				(17		)	—
	Other(4)	1				1			2			(1		)		(1		)	(2		)
	Ending balance	$	243			$	181		$	424		$	493			$	380		$	873
	Total allowance for loan losses:
	Beginning balance	$	40,521			$	3,325		$	43,846		$	50,519			$	8,276		$	58,795
	Benefit for loan losses(1)	(2,190		)		(240		)	(2,430		)	(4,661		)		(1,772		)	(6,433		)
	Charge-offs(2)(5)	(3,367		)		(143		)	(3,510		)	(4,752		)		(186		)	(4,938		)
	Recoveries	631				218			849			1,493				351			1,844
	Transfers(3)	759				(759		)	—			1,908				(1,908		)	—
	Other(4)	289				23			312			318				57			375
	Ending balance	$	36,643			$	2,424		$	39,067		$	44,825			$	4,818		$	49,643
	__________
	(1)	(Benefit) provision for loan losses is included in “Benefit for credit losses” in our condensed consolidated statements of operations and comprehensive income.
	(2)	While we purchase the substantial majority of loans that are four or more months delinquent from our MBS trusts, we do not exercise this option to purchase loans during a forbearance period. Charge-offs of consolidated trusts generally represent loans that remained in our consolidated trusts at the time of default.
(3)	Includes transfers from trusts for delinquent loan purchases.
(4)	Amounts represent the net activity recorded in our allowances for accrued interest receivable and preforeclosure property taxes and insurance receivable from borrowers. The (benefit) provision for loan losses, charge-offs, recoveries and transfer activity included in this table reflect all changes for both the allowance for loan losses and the valuation allowances for accrued interest and preforeclosure property taxes and insurance receivable that relate to the mortgage loans.
(5)	Total charge-offs include accrued interest of $75 million and $122 million for the three months ended June 30, 2014 and 2013, respectively, and $169 million and $237 million for the six months ended June 30, 2014 and 2013, respectively.
As of June 30, 2014, the allowance for accrued interest receivable for loans of Fannie Mae was $863 million and for loans of consolidated trusts was $81 million. As of December 31, 2013, the allowance for accrued interest receivable for loans of Fannie Mae was $1.1 billion and for loans of consolidated trusts was $104 million.
The following table displays the allowance for loan losses and total recorded investment in our HFI loans, excluding loans for which we have elected the fair value option, by impairment or reserve methodology and portfolio segment as of June 30, 2014 and December 31, 2013.
	As of
	June 30, 2014										December 31, 2013
	Single-Family			Multifamily				Total			Single-Family			Multifamily				Total
	(Dollars in millions)
Allowance for loan losses by segment:
Individually impaired loans(1)	$	34,624			$	249		$	34,873		$	37,423			$	306		$	37,729
Collectively reserved loans	4,019				175			4,194			5,884				233			6,117
Total allowance for loan losses	$	38,643			$	424		$	39,067		$	43,307			$	539		$	43,846
Recorded investment in loans by segment:(2)
Individually impaired loans(1)	$	188,395			$	3,351		$	191,746		$	189,064			$	4,215		$	193,279
Collectively reserved loans	2,665,958				179,595			2,845,553			2,689,627				181,763			2,871,390
Total recorded investment in loans	$	2,854,353			$	182,946		$	3,037,299		$	2,878,691			$	185,978		$	3,064,669
__________
(1)	Includes acquired credit-impaired loans.
(2)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.

Investments_in_Securities

Investments in Securities	6 Months Ended
	Jun. 30, 2014
Investments, Debt and Equity Securities [Abstract]	'
Investments in Securities	'
	Investments in Securities
	Trading Securities
	Trading securities are recorded at fair value with subsequent changes in fair value recorded as “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income. The following table displays our investments in trading securities as of June 30, 2014 and December 31, 2013.
		As of
		30-Jun-14						31-Dec-13
		(Dollars in millions)
	Mortgage-related securities:
	Fannie Mae		$	5,686					$	5,870
	Freddie Mac		1,766						1,839
	Ginnie Mae		234						407
	Alt-A private-label securities		1,194						1,516
	Subprime private-label securities		1,282						1,448
	CMBS		2,641						2,718
	Mortgage revenue bonds		643						565
	Other mortgage-related securities		101						99
	Total mortgage-related securities		13,547						14,462
	U.S. Treasury securities		13,083						16,306
	Total trading securities		$	26,630					$	30,768
	The following table displays information about our net trading gains and losses for the three and six months ended June 30, 2014 and 2013.
		For the Three								For the Six
		Months Ended								Months Ended
		June 30,								June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Net trading gains (losses)	$	249			$	(228	)		$	394			$	168
	Net trading gains (losses) recognized in the period related to securities still held at period end	233				(273		)		353				125
	Available-for-Sale Securities
	We measure available-for-sale (“AFS”) securities at fair value with unrealized gains and losses, recorded net of tax, as a component of “Other comprehensive income” and we recognize realized gains and losses from the sale of AFS securities in “Investment gains, net” in our condensed consolidated statements of operations and comprehensive income.
	The following table displays the gross realized gains, losses and proceeds on sales of AFS securities for the three and six months ended June 30, 2014 and 2013.
		For the Three								For the Six
		Months Ended								Months Ended
		June 30,								June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Gross realized gains	$	396			$	173			$	399			$	182
	Gross realized losses	—				53				2				57
	Total proceeds(1)	1,705				1,676				1,740				1,770
	__________
	s
	(1)	Excludes proceeds from the initial sale of securities from new portfolio securitizations included in “Note 2, Consolidations and Transfers of Financial Assets.”
	The following tables display the amortized cost, gross unrealized gains and losses, and fair value by major security type for AFS securities we held as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014
		Total Amortized Cost(1)						Gross Unrealized Gains						Gross Unrealized Losses - OTTI(2)						Gross Unrealized Losses - Other(3)						Total Fair Value
		(Dollars in millions)
	Fannie Mae		$	5,663					$	385					$	—					$	(26	)			$	6,022
	Freddie Mac		5,735						467						—						—					6,202
	Ginnie Mae		461						67						—						—					528
	Alt-A private-label securities		5,479						1,220						(18		)				—					6,681
	Subprime private-label securities		4,688						1,057						(19		)				(21		)			5,705
	CMBS		1,427						81						—						—					1,508
	Mortgage revenue bonds		4,669						79						(126		)				(62		)			4,560
	Other mortgage-related securities		2,781						214						(24		)				(151		)			2,820
	Total		$	30,903					$	3,570					$	(187	)				$	(260	)			$	34,026
		As of December 31, 2013
		Total Amortized Cost(1)						Gross Unrealized Gains						Gross Unrealized Losses - OTTI(2)						Gross Unrealized Losses - Other(3)						Total Fair Value
		(Dollars in millions)
	Fannie Mae		$	6,227					$	390					$	—					$	(44	)			$	6,573
	Freddie Mac		6,365						477						—						—					6,842
	Ginnie Mae		512						76						—						—					588
	Alt-A private-label securities		6,240						1,151						(40		)				(2		)			7,349
	Subprime private-label securities		6,232						991						(102		)				(53		)			7,068
	CMBS		1,526						80						—						—					1,606
	Mortgage revenue bonds		5,645						35						(228		)				(196		)			5,256
Other mortgage-related securities		2,943						164						(15		)				(203		)			2,889
Total		$	35,690					$	3,364					$	(385	)				$	(498	)			$	38,171
__________
(1)	Amortized cost consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments as well as net other-than-temporary impairments (“OTTI”) recognized in our condensed consolidated statements of operations and comprehensive income.
(2)	Represents the noncredit component of other-than-temporary impairments losses recorded in “Accumulated other comprehensive income” in our condensed consolidated balance sheets, as well as cumulative changes in fair value of securities for which we previously recognized the credit component of other-than-temporary impairments.
(3)	Represents the gross unrealized losses on securities for which we have not recognized other-than-temporary impairments.
The following tables display additional information regarding gross unrealized losses and fair value by major security type for AFS securities in an unrealized loss position that we held as of June 30, 2014 and December 31, 2013.
	As of June 30, 2014
	Less Than 12 Consecutive Months										12 Consecutive Months or Longer
	Gross Unrealized Losses						Fair Value				Gross Unrealized Losses						Fair Value
	(Dollars in millions)
Fannie Mae		$	(4	)			$	284				$	(22	)			$	673
Alt-A private-label securities		(3		)			121					(15		)			113
Subprime private-label securities		(2		)			72					(38		)			618
Mortgage revenue bonds		(2		)			66					(186		)			1,396
Other mortgage-related securities		—					5					(175		)			1,050
Total		$	(11	)			$	548				$	(436	)			$	3,850
	As of December 31, 2013
	Less Than 12 Consecutive Months										12 Consecutive Months or Longer
	Gross Unrealized Losses						Fair Value				Gross Unrealized Losses						Fair Value
	(Dollars in millions)
Fannie Mae		$	(40	)			$	975				$	(4	)			$	126
Alt-A private-label securities		(12		)			490					(30		)			308
Subprime private-label securities		(24		)			448					(131		)			1,332
Mortgage revenue bonds		(147		)			1,662					(277		)			970
Other mortgage-related securities		—					5					(218		)			1,066
Total		$	(223	)			$	3,580				$	(660	)			$	3,802
Other-Than-Temporary Impairments
We evaluate AFS securities for other-than-temporary impairment on a quarterly basis. An other-than-temporary impairment is considered to have occurred when the fair value of a debt security is below its amortized cost basis and we intend to sell or it is more likely than not that we will be required to sell the security before recovery. An other-than-temporary impairment is also considered to have occurred if we do not expect to recover the entire amortized cost basis of a debt security even if we do not intend to sell the security or it is not more likely than not we will be required to sell the security before recovery.
The following table displays the modeled attributes, including default rates and severities, which were used to determine as of June 30, 2014 whether our senior interests in certain non-agency mortgage-related securities (including those we intend to sell) will experience a cash shortfall. An estimate of voluntary prepayment rates is also an input to the present value of expected losses.
	As of June 30, 2014
					Alt-A
	Subprime				Option ARM						Fixed Rate						Variable Rate						Hybrid Rate
	(Dollars in millions)
Vintage Year
2004 & Prior:
Unpaid principal balance	$	117				$	117					$	920					$	133					$	328
Weighted average collateral default(1)	26.5		%			23.9		%				9.5		%				20.8		%				13.3		%
Weighted average collateral severities(2)	55.2					54.5						52						40.8						38.5
Weighted average voluntary prepayment rates(3)	10.1					9.7						13.4						9.9						10.2
Average credit enhancement(4)	38.4					4.1						10.9						21.3						9.4
2005:00:00
Unpaid principal balance	$	41				$	472					$	828					$	384					$	1,348
Weighted average collateral default(1)	49		%			31.9		%				22.9		%				33		%				26.4		%
Weighted average collateral severities(2)	60					53.5						54						47.7						44.2
Weighted average voluntary prepayment rates(3)	2.9					7.5						10.4						8.5						9.1
Average credit enhancement(4)	47.9					8.9						0.6						12.6						2.8
2006:00:00
Unpaid principal balance	$	7,527				$	690					$	393					$	1,088					$	1,193
Weighted average collateral default(1)	53		%			42.1		%				24.4		%				36.3		%				18.1		%
Weighted average collateral severities(2)	61.4					48.3						55.2						47.7						43.7
Weighted average voluntary prepayment rates(3)	2.4					6.1						8.3						7.7						10.1
Average credit enhancement(4)	10.3					2.9						0.1						0.7						—
2007 & After:
Unpaid principal balance	$	341				$	—					$	—					$	—					$	83
Weighted average collateral default(1)	50.4		%			N/A						N/A						N/A						21.9		%
Weighted average collateral severities(2)	28					N/A						N/A						N/A						39.9
Weighted average voluntary prepayment rates(3)	1.4					N/A						N/A						N/A						9.9
Average credit enhancement(4)	20.3					N/A						N/A						N/A						20.4
Total:
Unpaid principal balance	$	8,026				$	1,279					$	2,141					$	1,605					$	2,952
Weighted average collateral default(1)	52.5		%			36.7		%				17.4		%				34.2		%				21.5		%
Weighted average collateral severities(2)	60					50.3						53.8						47.3						43.5
Weighted average voluntary prepayment rates(3)	2.5					7						11.3						8.1						9.6
Average credit enhancement(4)	11.4					5.2						4.9						5.3						2.9
__________
(1)	The expected remaining cumulative default rate of the collateral pool backing the securities, as a percentage of the current collateral unpaid principal balance, weighted by security unpaid principal balance.
(2)	The expected remaining loss given default of the collateral pool backing the securities, calculated as the ratio of remaining cumulative loss divided by cumulative defaults, weighted by security unpaid principal balance.
(3)	The average monthly voluntary prepayment rate, weighted by security unpaid principal balance.
(4)	The average percent current credit enhancement provided by subordination of other securities. Excludes excess interest projections and monoline bond insurance.
The following table displays activity related to the unrealized credit loss component on debt securities held by us and recognized in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013.
	For the Three Months Ended								For the Six Months Ended
	June 30,								June 30,
	2014				2013				2014				2013
	(Dollars in millions)
Balance, beginning of period	$	7,096			$	9,136			$	7,904			$	9,214
Additions for the credit component on debt securities for which OTTI was not previously recognized	—				2				1				7
Additions for the credit component on debt securities for which OTTI was previously recognized	8				4				47				8
Reductions for securities no longer in portfolio at period end	(384		)		(81		)		(437		)		(83		)
Reductions for securities which we intend to sell or it is more likely than not that we will be required to sell before recovery of amortized cost basis	(755		)		—				(1,453		)		—
Reductions for amortization resulting from changes in cash flows expected to be collected over the remaining life of the securities	(94		)		(97		)		(191		)		(182		)
Balance, end of period	$	5,871			$	8,964			$	5,871			$	8,964
Maturity Information
The following table displays the amortized cost and fair value of our AFS securities by major security type and remaining contractual maturity, assuming no principal prepayments, as of June 30, 2014. The contractual maturity of mortgage-backed securities is not a reliable indicator of their expected life because borrowers generally have the right to prepay their obligations at any time.
	As of June 30, 2014
	Total Amortized Cost						Total				One Year or Less										After One Year Through Five Years								After Five Years Through Ten Years					After Ten Years
							Fair
							Value				Amortized Cost						Fair Value				Amortized Cost						Fair Value		Amortized Cost			Fair Value		Amortized Cost			Fair Value
	(Dollars in millions)
Fannie Mae		$	5,663				$	6,022				$	—				$	—				$	321				$	339		$	284	$	307		$	5,058	$	5,376
Freddie Mac		5,735					6,202					—					—					367					389			590		646			4,778		5,167
Ginnie Mae		461					528					—					—					—					—			66		75			395		453
Alt-A private-label securities		5,479					6,681					—					—					—					—			—		—			5,479		6,681
Subprime private-label securities		4,688					5,705					—					—					—					—			—		—			4,688		5,705
CMBS		1,427					1,508					—					—					1,345					1,424			—		—			82		84
Mortgage revenue bonds		4,669					4,560					26					27					209					212			467		470			3,967		3,851
Other mortgage-related securities		2,781					2,820					—					—					—					3			36		39			2,745		2,778
Total		$	30,903				$	34,026				$	26				$	27				$	2,242				$	2,367		$	1,443	$	1,537		$	27,192	$	30,095

Financial_Guarantees

Financial Guarantees	6 Months Ended
	Jun. 30, 2014
Guarantees [Abstract]	'
Financial Guarantees	'
	Financial Guarantees
	We recognize a guaranty obligation for our obligation to stand ready to perform on our guarantees to unconsolidated trusts and other guaranty arrangements. These guarantees expose us to credit losses on the mortgage loans or, in the case of mortgage-related securities, the underlying mortgage loans of the related securities. The contractual terms of our guarantees range from 30 days to 40 years; however, the actual term of each guaranty may be significantly less than the contractual term based on the prepayment characteristics of the related mortgage loans.
	The following table displays our maximum exposure, guaranty obligation recognized in our condensed consolidated balance sheets and the maximum potential recovery from third parties through available credit enhancements and recourse related to our financial guarantees as of June 30, 2014 and December 31, 2013.
		As of
		30-Jun-14													31-Dec-13
		Maximum Exposure(1)			Guaranty Obligation				Maximum Recovery(2)					Maximum Exposure(1)			Guaranty Obligation			Maximum Recovery(2)
		(Dollars in millions)
	Non-consolidated Fannie Mae MBS	$	18,257			$	222			$	10,332				$	19,317		$	232		$	10,541
	Other guaranty arrangements(3)	28,951				231				4,569					30,598			253			4,525
	Total	$	47,208			$	453			$	14,901				$	49,915		$	485		$	15,066
	__________
	(1)	Primarily consists of the unpaid principal balance of the underlying mortgage loans.
	(2)	Recoverability of such credit enhancements and recourse is subject to, among other factors, our mortgage insurers’ and financial guarantors’ ability to meet their obligations to us. For information on our mortgage insurers, see “Note 14, Concentrations of Credit Risk.”
	(3)	Primarily consists of credit enhancements, long-term standby commitments, and our commitment under the TCLF program.
	The fair value of our guaranty obligations associated with the Fannie Mae MBS included in “Investments in securities” in our condensed consolidated balance sheets was $931 million and $1.1 billion as of June 30, 2014 and December 31, 2013, respectively. These Fannie Mae MBS consist primarily of private-label wraps where our guaranty arrangement is with an unconsolidated MBS trust.
	Risk Characteristics of our Book of Business
	We gauge our performance risk under our guaranty based on the delinquency status of the mortgage loans we hold in our retained mortgage portfolio, or in the case of mortgage-backed securities, the mortgage loans underlying the related securities.
	For single-family loans, management monitors the serious delinquency rate, which is the percentage of single-family loans 90 days or more past due or in the foreclosure process, and loans that have higher risk characteristics, such as high mark-to-market LTV ratios.
	For multifamily loans, management monitors the serious delinquency rate, which is the percentage of loans 60 days or more past due, and other loans that have higher risk characteristics, to determine our overall credit quality indicator. Higher risk characteristics include, but are not limited to, current DSCR below 1.0 and high original and current estimated LTV ratios. We stratify multifamily loans into different internal risk categories based on the credit risk inherent in each individual loan.
	For single-family and multifamily loans, we use this information, in conjunction with housing market and economic conditions, to structure our pricing and our eligibility and underwriting criteria to reflect the current risk of loans with these higher-risk characteristics, and in some cases we decide to significantly reduce our participation in riskier loan product categories. Management also uses this data together with other credit risk measures to identify key trends that guide the development of our loss mitigation strategies.
	The following tables display the current delinquency status and certain higher risk characteristics of our single-family conventional and total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014(1)							December 31, 2013(1)
		30 Days Delinquent		60 Days Delinquent			Seriously Delinquent(2)		30 Days Delinquent			60 Days Delinquent			Seriously Delinquent(2)
	Percentage of single-family conventional guaranty book of business(3)	1.27	%	0.38	%		2.18	%	1.41	%		0.44	%		2.54	%
	Percentage of single-family conventional loans(4)	1.46		0.42			2.05		1.64			0.49			2.38
		As of
		June 30, 2014(1)					December 31, 2013(1)
		Percentage of		Percentage Seriously Delinquent(2)(5)			Percentage of		Percentage Seriously Delinquent(2)(5)
		Single-Family					Single-Family
		Conventional					Conventional
		Guaranty Book of Business(3)					Guaranty Book of Business(3)
	Estimated mark-to-market loan-to-value ratio:
	Greater than 100%	6	%	11.4	%		7	%	12.22	%
	Geographical distribution:
	California	20		0.77			20		0.98
	Florida	6		5.46			6		6.89
	Illinois	4		2.6			4		3.12
	New Jersey	4		5.94			4		6.25
	New York	5		4.24			5		4.42
	All other states	61		1.6			61		1.85
	Product distribution:
	Alt-A	4		8.37			5		9.23
	Subprime	*		15.65			*		16.93
	Vintages:
	2005	3		6.47			4		7.26
	2006	3		10.11			3		11.26
	2007	4		11.08			5		12.18
	2008	3		6.27			3		6.69
	All other vintages	87		0.91			85		1.02
	Select combined risk characteristics:
	Original LTV ratio > 90% and FICO score < 620	1		9.34			1		10.9
	__________
	*	Represents less than 0.5% of the single-family conventional guaranty book of business.
	(1)	Consists of the portion of our single-family conventional guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total single-family conventional guaranty book of business as of June 30, 2014 and December 31, 2013.
	(2)	Consists of single-family conventional loans that were 90 days or more past due or in the foreclosure process as of June 30, 2014 and December 31, 2013.
	(3)	Calculated based on the aggregate unpaid principal balance of single-family conventional loans for each category divided by the aggregate unpaid principal balance of loans in our single-family conventional guaranty book of business.
	(4)	Calculated based on the number of single-family conventional loans that were delinquent divided by the total number of loans in our single-family conventional guaranty book of business.
	(5)	Calculated based on the number of single-family conventional loans that were seriously delinquent divided by the total number of single-family conventional loans for each category included in our guaranty book of business.
		As of
		June 30, 2014(1)(2)					December 31, 2013(1)(2)
		30 Days Delinquent		Seriously Delinquent(3)			30 Days Delinquent		Seriously Delinquent(3)
	Percentage of multifamily guaranty book of business	0.03	%	0.1	%		0.03	%	0.1	%
	As of
	June 30, 2014(1)					December 31, 2013(1)
	Percentage of Multifamily Guaranty Book of Business(2)		Percentage Seriously Delinquent(3)(4)			Percentage of Multifamily Guaranty Book of Business(2)		Percentage Seriously Delinquent(3)(4)
Original LTV ratio:
Greater than 80%	3	%	0.17	%		3	%	0.23	%
Less than or equal to 80%	97		0.1			97		0.1
Current debt service coverage ratio less than 1.0(5)	3		0.95			4		1.09
__________
(1)	Consists of the portion of our multifamily guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013 excluding loans that have been defeased.
(2)	Calculated based on the aggregate unpaid principal balance of multifamily loans for each category divided by the aggregate unpaid principal balance of loans in our multifamily guaranty book of business.
(3)	Consists of multifamily loans that were 60 days or more past due as of the dates indicated.
(4)	Calculated based on the unpaid principal balance of multifamily loans that were seriously delinquent divided by the aggregate unpaid principal balance of multifamily loans for each category included in our guaranty book of business.
(5)	Our estimates of current DSCRs are based on the latest available income information for these properties. Although we use the most recently available results of our multifamily borrowers, there is a lag in reporting, which typically can range from 3 to 6 months but in some cases may be longer.

Acquired_Property_Net

Acquired Property Net	6 Months Ended
	Jun. 30, 2014
Real Estate [Abstract]	'
Acquired Property, Net	'
	Acquired Property, Net
	Acquired property, net consists of held-for-sale foreclosed property received in satisfaction of a loan, net of a valuation allowance for declines in the fair value of the properties after initial acquisition. We classify properties as held-for-sale when we intend to sell the property and are actively marketing it for sale. The following table displays the activity in acquired property, and the related valuation allowance, for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,						For the Six Months
								Ended June 30,
		2014			2013			2014			2013
		(Dollars in millions)
	Beginning balance — Acquired property	$	12,744		$	10,719		$	12,307		$	11,158
	Additions	3,425			4,195			7,197			7,969
	Disposals	(3,873		)	(4,108		)	(7,208		)	(8,321		)
	Ending balance — Acquired property	$	12,296		$	10,806		$	12,296		$	10,806
	Beginning balance — Valuation allowance	(784		)	(570		)	(686		)	(669		)
	Decrease (increase) in valuation allowance	48			30			(50		)	129
	Ending balance — Valuation allowance	(736		)	(540		)	(736		)	(540		)
	Ending balance — Acquired property, net	$	11,560		$	10,266		$	11,560		$	10,266

ShortTerm_Borrowings_and_LongT

Short-Term Borrowings and Long-Term Debt	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Short-Term Borrowings and Long-Term Debt	'
	Short-Term Borrowings and Long-Term Debt
	Short-Term Borrowings
	The following table displays our outstanding short-term borrowings (borrowings with an original contractual maturity of one year or less) and weighted-average interest rates of these borrowings as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014									December 31, 2013
		Outstanding					Weighted- Average Interest Rate(1)				Outstanding					Weighted- Average Interest Rate(1)
			(Dollars in millions)
	Fixed-rate short-term debt:
	Discount notes(2)		$	90,926				0.1	%			$	71,933				0.12	%
	Foreign exchange discount notes(3)		—					—				362					1.07
	Total short-term debt of Fannie Mae		90,926					0.1				72,295					0.13
	Debt of consolidated trusts		1,844					0.1				2,154					0.09
	Total short-term debt		$	92,770				0.1	%			$	74,449				0.13	%
	__________
	(1)	Includes the effects of discounts, premiums and other cost basis adjustments.
	(2)	Represents unsecured general obligations with maturities ranging from overnight to 360 days from the date of issuance.
	(3)	Represents foreign exchange discount notes issued in the Euro commercial paper market with maturities ranging from 5 to 360 days which enable investors to hold short-term investments in different currencies. We do not incur foreign exchange risk on these transactions, as we simultaneously enter into foreign currency swaps that have the effect of converting debt that we issue in foreign denominated currencies into U.S. dollars.
	Intraday Lines of Credit
	We periodically use secured intraday funding lines of credit provided by large financial institutions. We post collateral which, in some circumstances, the secured party has the right to repledge to third parties. As these lines of credit are uncommitted intraday loan facilities, we may be unable to draw on them if and when needed. We had secured uncommitted lines of credit of $20.0 billion as of June 30, 2014 and December 31, 2013. We had no borrowings outstanding from these lines of credit as of June 30, 2014 or December 31, 2013.
	Long-Term Debt
	Long-term debt represents borrowings with an original contractual maturity of greater than one year. The following table displays our outstanding long-term debt as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014									December 31, 2013
		Maturities		Outstanding					Weighted- Average Interest Rate(1)		Maturities		Outstanding					Weighted- Average Interest Rate(1)
		(Dollars in millions)
	Senior fixed:
	Benchmark notes and bonds	2014 - 2030			$	186,556			2.4	%	2014 - 2030			$	212,234			2.45	%
	Medium-term notes(2)	2014 - 2024			124,483				1.36		2014 - 2023			161,445				1.28
	Foreign exchange notes and bonds	2021 - 2028			680				5.25		2021 - 2028			682				5.41
	Other(3)	2014 - 2038			36,061				5.02		2014 - 2038			38,444				4.99
	Total senior fixed				347,780				2.31					412,805				2.24
	Senior floating:
	Medium-term notes(2)	2014 - 2019			31,493				0.18		2014 - 2019			38,441				0.2
	Other(3)(4)	2020 - 2037			3,432				3.18		2020 - 2037			955				5.18
	Total senior floating				34,925				0.46					39,396				0.32
	Subordinated fixed:
	Qualifying subordinated	—			—				—		2014			1,169				5.27
	Subordinated debentures	2019			3,674				9.92		2019			3,507				9.92
	Total subordinated fixed				3,674				9.92					4,676				8.76
	Secured borrowings(5)	2021 - 2022			230				1.88		2021 - 2022			262				1.86
	Total long-term debt of Fannie Mae(6)				386,609				2.21					457,139				2.14
	Debt of consolidated trusts(3)	2014 - 2054			2,710,166				3.17		2014 - 2053			2,702,935				3.26
	Total long-term debt				$	3,096,775			3.05	%				$	3,160,074			3.1	%
	__________
	(1)	Includes the effects of discounts, premiums and other cost basis adjustments.
	(2)	Includes long-term debt with an original contractual maturity of greater than 1 year and up to 10 years, excluding zero-coupon debt.
	(3)	Includes a portion of structured debt instruments that is reported at fair value.
	(4)	Includes credit risk sharing securities issued under our Connecticut Avenue Securities series, which transfers some of the credit risk of our mortgage loans to the investors in these securities.
	(5)	Represents our remaining liability resulting from the transfer of financial assets from our condensed consolidated balance sheets that did not qualify as a sale under the accounting guidance for the transfer of financial instruments.
	(6)	Reported amounts include unamortized discounts and premiums, other cost basis adjustments and fair value adjustments of $4.1 billion and $4.8 billion as of June 30, 2014 and December 31, 2013, respectively.

Derivative_Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments	'
	Derivative Instruments
	Derivative instruments are an integral part of our strategy in managing interest rate risk. Derivative instruments may be privately-negotiated, bilateral contracts, or they may be listed and traded on an exchange. We refer to our derivative transactions made pursuant to bilateral contracts as our over-the-counter (“OTC”) derivative transactions and our derivative transactions accepted for clearing by a derivatives clearing organization as our OTC-cleared derivative transactions. We typically do not settle the notional amount of our risk management derivatives; rather, notional amounts provide the basis for calculating annual payments or settlement amounts. The derivatives we use for interest rate risk management purposes consist primarily of interest rate swaps and interest rate options.
	We enter into forward purchase and sale commitments that lock in the future delivery of mortgage loans and mortgage-related securities at a fixed price or yield. Certain commitments to purchase mortgage loans and purchase or sell mortgage-related securities meet the criteria of a derivative. We typically settle the notional amount of our mortgage commitments that are accounted for as derivatives.
	We recognize all derivatives as either assets or liabilities in our condensed consolidated balance sheets at their fair value on a trade date basis. Fair value amounts, which are netted to the extent a legal right of offset exists and is enforceable by law at the counterparty level and are inclusive of the right or obligation associated with the cash collateral posted or received, are recorded in “Other assets” or “Other liabilities” in our condensed consolidated balance sheets. We present cash flows from derivatives as operating activities in our condensed consolidated statements of cash flows.
	Notional and Fair Value Position of our Derivatives
	The following table displays the notional amount and estimated fair value of our asset and liability derivative instruments as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014												As of December 31, 2013
		Asset Derivatives						Liability Derivatives						Asset Derivatives					Liability Derivatives
		Notional Amount			Estimated Fair Value			Notional Amount			Estimated Fair Value			Notional Amount		Estimated Fair Value			Notional Amount		Estimated Fair Value
		(Dollars in millions)
	Risk management derivatives:
	Swaps:
	Pay-fixed	$	52,489		$	2,340		$	105,272		$	(6,019	)	$	68,637	$	5,378		$	93,428	$	(4,759	)
	Receive-fixed	66,478			4,179			133,397			(1,629		)	67,527		3,320			156,250		(3,813		)
	Basis	13,914			79			6,850			(1		)	27,014		36			600		—
	Foreign currency	377			139			299			(16		)	389		120			653		(38		)
	Swaptions:
	Pay-fixed	25,150			94			43,525			(264		)	33,400		445			48,025		(600		)
	Receive-fixed	4,500			216			46,525			(721		)	8,000		117			48,025		(484		)
	Other(1)	109			29			37			(1		)	769		28			13		(1		)
	Total gross risk management derivatives	163,017			7,076			335,905			(8,651		)	205,736		9,444			346,994		(9,695		)
	Accrued interest receivable (payable)	—			696			—			(950		)	—		786			—		(930		)
	Netting adjustment(2)	—			(6,897		)	—			9,390			—		(8,422		)	—		9,370
	Total net risk management derivatives	$	163,017		$	875		$	335,905		$	(211	)	$	205,736	$	1,808		$	346,994	$	(1,255	)
	Mortgage commitment derivatives:
	Mortgage commitments to purchase whole loans	$	7,728		$	44		$	235		$	—		$	1,138	$	1		$	4,353	$	(31	)
	Forward contracts to purchase mortgage-related securities	40,214			343			663			(2		)	3,276		4			20,861		(168		)
	Forward contracts to sell mortgage-related securities	484			2			60,336			(523		)	35,423		260			7,886		(15		)
	Total mortgage commitment derivatives	$	48,426		$	389		$	61,234		$	(525	)	$	39,837	$	265		$	33,100	$	(214	)
	Derivatives at fair value	$	211,443		$	1,264		$	397,139		$	(736	)	$	245,573	$	2,073		$	380,094	$	(1,469	)
	__________
	(1)	Includes interest rate caps, futures, swap credit enhancements and mortgage insurance contracts that we account for as derivatives. The mortgage insurance contracts have payment provisions that are not based on a notional amount.
	(2)	The netting adjustment for our risk management derivatives transactions represents the effect of the legal right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received. Cash collateral posted was $3.3 billion and $2.0 billion as of June 30, 2014 and December 31, 2013, respectively. Cash collateral received was $780 million and $1.0 billion as of June 30, 2014 and December 31, 2013, respectively.
	A majority of our OTC derivative contracts contain provisions that require our senior unsecured debt to maintain a minimum credit rating from S&P and Moody’s. If our senior unsecured debt credit ratings were downgraded to established thresholds in these derivative contracts, which range from A+ to BBB+, we could be required to provide additional collateral to or terminate transactions with certain counterparties. The aggregate fair value of all OTC derivatives with credit-risk-related contingent features that were in a net liability position was $2.3 billion and $2.1 billion, for which we posted collateral of $2.1 billion and $2.0 billion in the normal course of business as of June 30, 2014 and December 31, 2013, respectively. Had all of the credit-risk-related contingency features underlying these agreements been triggered, an additional $174 million and $130 million would have been required to be posted as collateral or to immediately settle our positions based on the individual agreements and our fair value position as of June 30, 2014 and December 31, 2013, respectively. A reduction in our credit ratings may also cause derivatives clearing organizations or their members to demand that we post additional collateral for our OTC-cleared derivative contracts.
	We record all derivative gains and losses, including accrued interest, in “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income. The following table displays, by type of derivative instrument, the fair value gains and losses, net on our derivatives for the three and six months ended June 30, 2014 and 2013.
		For the						For the
		Three Months						Six Months
		Ended June 30,						Ended June 30,
		2014			2013			2014			2013
		(Dollars in millions)
	Risk management derivatives:
	Swaps:
	Pay-fixed	$	(2,349	)	$	8,313		$	(4,467	)	$	10,903
	Receive-fixed	1,639			(7,123		)	3,104			(9,033		)
	Basis	8			(45		)	43			(72		)
	Foreign currency	17			(63		)	38			(133		)
	Swaptions:
	Pay-fixed	62			(468		)	(37		)	(451		)
	Receive-fixed	(59		)	247			(101		)	268
	Other	3			11			—			21
	Accrual of periodic settlements:
	Pay-fixed interest-rate swaps	(913		)	(1,211		)	(1,816		)	(2,409		)
	Receive-fixed interest-rate swaps	642			1,012			1,333			1,994
	Other	14			18			27			34
	Total risk management derivatives fair value (losses) gains, net	$	(936	)	$	691		$	(1,876	)	$	1,122
	Mortgage commitment derivatives fair value (losses) gains, net	(310		)	497			(655		)	628
	Total derivatives fair value (losses) gains, net	$	(1,246	)	$	1,188		$	(2,531	)	$	1,750
	Derivative Counterparty Credit Exposure
	Our derivative counterparty credit exposure relates principally to interest rate derivative contracts. We are exposed to the risk that a counterparty in a derivative transaction will default on payments due to us, which may require us to seek a replacement derivative from a different counterparty. This replacement may be at a higher cost, or we may be unable to find a suitable replacement. We manage our derivative counterparty credit exposure relating to our risk management derivative transactions mainly through enforceable master netting arrangements, which allow us to net derivative assets and liabilities with the same counterparty or clearing organization. For our risk management derivative transactions, we require counterparties to post collateral, which may include cash, U.S. Treasury securities, agency debt and agency mortgage-related securities.
	See “Note 15, Netting Arrangements” for information on our rights to offset assets and liabilities.

Income_Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Tax	'
	Income Taxes
	We recognized a provision for federal income taxes of $1.8 billion for the three months ended June 30, 2014, which resulted in an effective tax rate of 32.3%. For the six months ended June 30, 2014, we recognized a provision for federal income taxes of $4.3 billion, which resulted in an effective tax rate of 32.5%.
	We recognized a provision for federal income taxes of $2.0 billion for the three months ended June 30, 2013, which resulted in an effective tax rate of 16.4%. For the six months ended June 30, 2013, we recognized a benefit for federal income taxes of $48.6 billion, which resulted in an effective tax rate of (240.6)%.
	For the three months and six months ended June 30, 2014, the effective tax rates were different from the federal statutory rate of 35% primarily due to the benefits of our investments in housing projects eligible for the low-income housing tax credit. Our effective tax rates for the three months and six months ended June 30, 2013 were different from the statutory rate of 35% primarily due to the release of our valuation allowance for our net deferred tax assets.

Earnings_Loss_Per_Share

Earnings (Loss) Per Share	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Earnings (Loss) Per Share	'
	Loss Per Share
	The calculation of income available to common stockholders and earnings per share is based on the underlying premise that all income after payment of dividends on preferred shares is available to and will be distributed to common stockholders. However, as a result of our conservatorship status and the terms of the senior preferred stock, no amounts are available to distribute as dividends to common or preferred stockholders (other than to Treasury as holder of the senior preferred stock).
	The following table displays the computation of basic and diluted loss per share of common stock for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,								For the Six Months Ended June 30,
		2014				2013				2014				2013
		(Dollars and shares in millions, except per share amounts)
	Net income		$	3,667			$	10,095			$	8,992			$	68,780
	Less: Net income attributable to noncontrolling interest		(1		)		(11		)		(1		)		(11		)
	Net income attributable to Fannie Mae		3,666				10,084				8,991				68,769
	Dividends distributed or available for distribution to senior preferred stockholder(1)		(3,712		)		(10,243		)		(9,404		)		(69,611		)
	Net loss attributable to common stockholders		$	(46	)		$	(159	)		$	(413	)		$	(842	)
	Weighted-average common shares outstanding—basic and diluted(2)		5,762				5,762				5,762				5,762
	Loss per share: basic and diluted		$	(0.01	)		$	(0.03	)		$	(0.07	)		$	(0.15	)
	__________
	(1)	Represents our dividend payments to Treasury under the terms of the senior preferred stock. Dividends distributed or available for distribution for the three months ended June 30, 2014 (relating to the dividend period for the three months ended September 30, 2014) were calculated based on our net worth as of June 30, 2014 less the applicable capital reserve amount of $2.4 billion and for the six months ended June 30, 2014 we add dividends paid on June 30, 2014 to this amount. Dividends distributed or available for distribution for the three months ended June 30, 2013 (relating to the dividend period for the three months ended September 30, 2013) were calculated based on our net worth as of June 30, 2013 less the applicable capital reserve amount of $3.0 billion and for the six months ended June 30, 2013 we add dividends paid on June 30, 2013 to this amount.
	(2)	Includes 4.6 billion of weighted average shares of common stock that would be issued upon the full exercise of the warrant issued to Treasury from the date the warrant was issued through June 30, 2014.

Segment_Reporting

Segment Reporting	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	Segment Reporting
	Our three reportable segments are: Single-Family, Multifamily and Capital Markets. We use these three segments to generate revenue and manage business risk, and each segment is based on the type of business activities it performs. Under our segment reporting, the sum of the results for our three business segments does not equal our condensed consolidated statements of operations and comprehensive income, as we separate the activity related to our consolidated trusts from the results generated by our three segments. Our business segment financial results include directly attributable revenues and expenses. Additionally, we allocate to each of our segments: (1) capital using FHFA minimum capital requirements adjusted for over- or under-capitalization; (2) indirect administrative costs; and (3) a provision or benefit for federal income taxes. In addition, we allocate intracompany guaranty fee income as a charge from the Single-Family and Multifamily segments to Capital Markets for managing the credit risk on mortgage loans held by the Capital Markets group. We also include an eliminations/adjustments category to reconcile our business segment financial results and the activity related to our consolidated trusts to net income in our condensed consolidated statements of operations and comprehensive income.
	The following tables display our business segment financial results for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30, 2014
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest income (loss)	$	5			$	(21	)	$	1,917			$	2,739			$	264		(3)	$	4,904
	Benefit for credit losses	1,603				36			—				—				—				1,639
	Net interest income after benefit for credit losses	1,608				15			1,917				2,739				264				6,543
	Guaranty fee income (expense)(4)	2,893				317			(241		)		(1,452		)	(5)	(1,476		)	(5)	41			(5)
	Investment (losses) gains, net	(1		)		39			1,648				(104		)		(1,076		)	(6)	506
	Net other-than-temporary impairments	—				—			(23		)		—				—				(23		)
	Fair value (losses) gains, net	(2		)		—			(1,098		)		171				(5		)	(7)	(934		)
	Debt extinguishment gains (losses), net	—				—			41				(3		)		—				38
	Gains from partnership investments(8)	—				34			—				—				1				35
	Fee and other income (expense)	181				31			136				(95		)		89				342
	Administrative expenses	(458		)		(75		)	(164		)		—				—				(697		)
	Foreclosed property income	178				36			—				—				—				214
	TCCA fees(4)	(335		)		—			—				—				—				(335		)
	Other expenses	(237		)		(12		)	(57		)		—				(5		)		(311		)
	Income before federal income taxes	3,827				385			2,159				1,256				(2,208		)		5,419
	Provision for federal income taxes	(1,133		)		(9		)	(610		)		—				—				(1,752		)
	Net income	2,694				376			1,549				1,256				(2,208		)		3,667
	Less: Net income attributable to noncontrolling interest	—				—			—				—				(1		)	(9)	(1		)
	Net income attributable to Fannie Mae	$	2,694			$	376		$	1,549			$	1,256			$	(2,209	)		$	3,666
		For the Six Months Ended June 30, 2014
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest (loss) income	$	(43	)		$	(43	)	$	3,747			$	5,437			$	544		(3)	$	9,642
	Benefit for credit losses	2,348				65			—				—				—				2,413
	Net interest income after benefit for credit losses	2,305				22			3,747				5,437				544				12,055
	Guaranty fee income (expense)(4)	5,763				628			(487		)		(2,879		)	(5)	(2,939		)	(5)	86			(5)
	Investment (losses) gains, net	(1		)		42			2,984				(162		)		(2,211		)	(6)	652
	Net other-than-temporary impairments	—				—			(74		)		—				—				(74		)
	Fair value (losses) gains, net	(7		)		—			(2,435		)		219				99			(7)	(2,124		)
	Debt extinguishment gains, net	—				—			34				4				—				38
	Gains from partnership investments(8)	—				79			—				—				1				80
	Fee and other income (expense)	325				55			4,269				(171		)		174				4,652
	Administrative expenses	(908		)		(148		)	(313		)		—				—				(1,369		)
	Foreclosed property income	435				41			—				—				—				476
	TCCA fees(4)	(657		)		—			—				—				—				(657		)
	Other expenses	(392		)		(13		)	(65		)		—				(17		)		(487		)
	Income before federal income taxes	6,863				706			7,660				2,448				(4,349		)		13,328
	Provision for federal income taxes	(2,060		)		—			(2,276		)		—				—				(4,336		)
	Net income	4,803				706			5,384				2,448				(4,349		)		8,992
	Less: Net income attributable to noncontrolling interest	—				—			—				—				(1		)	(9)	(1		)
	Net income attributable to Fannie Mae	$	4,803			$	706		$	5,384			$	2,448			$	(4,350	)		$	8,991
		For the Three Months Ended June 30, 2013(10)
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest (loss) income	$	(50	)		$	(17	)	$	2,680			$	2,621			$	433		(3)	$	5,667
	Benefit for credit losses	5,353				30			—				—				—				5,383
	Net interest income after benefit for credit losses	5,303				13			2,680				2,621				433				11,050
	Guaranty fee income (expense)(4)	2,544				300			(283		)		(1,283		)	(5)	(1,227		)	(5)	51			(5)
	Investment gains (losses), net	1				4			898				(89		)		(524		)	(6)	290
	Net other-than-temporary impairments	—				—			(6		)		—				—				(6		)
	Fair value (losses) gains, net	(1		)		—			841				(214		)		203			(7)	829
	Debt extinguishment gains, net	—				—			3				24				—				27
	Gains from partnership investments(8)	—				104			—				—				11				115
	Fee and other income (expense)	179				38			255				(86		)		48				434
Administrative expenses	(419		)		(67		)	(140		)		—				—				(626		)
Foreclosed property income	328				4			—				—				—				332
TCCA fees(4)	(233		)		—			—				—				—				(233		)
Other expenses	(154		)		—			(8		)		—				(21		)		(183		)
Income before federal income taxes	7,548				396			4,240				973				(1,077		)		12,080
Provision for federal income taxes	(1,050		)		(10		)	(925		)		—				—				(1,985		)
Net income	6,498				386			3,315				973				(1,077		)		10,095
Less: Net income attributable to noncontrolling interest	—				—			—				—				(11		)	(9)	(11		)
Net income attributable to Fannie Mae	$	6,498			$	386		$	3,315			$	973			$	(1,088	)		$	10,084
	For the Six Months Ended June 30, 2013(10)
	Business Segments										Other Activity/Reconciling Items
	Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
	(Dollars in millions)
Net interest income (loss)	$	470			$	(28	)	$	5,422			$	5,218			$	889		(3)	$	11,971
Benefit for credit losses	6,134				206			—				—				—				6,340
Net interest income after benefit for credit losses	6,604				178			5,422				5,218				889				18,311
Guaranty fee income (expense)(4)	4,919				591			(582		)		(2,487		)	(5)	(2,336		)	(5)	105			(5)
Investment gains (losses), net	3				11			2,247				(156		)		(1,697		)	(6)	408
Net other-than-temporary impairments	—				—			(15		)		—				—				(15		)
Fair value (losses) gains, net	(3		)		—			1,716				(418		)		368			(7)	1,663
Debt extinguishment (losses) gains, net	—				—			(37		)		41				—				4
Gains from partnership investments(8)	—				163			—				—				11				174
Fee and other income (expense)	351				89			604				(170		)		74				948
Administrative expenses	(845		)		(137		)	(285		)		—				—				(1,267		)
Foreclosed property income	581				11			—				—				—				592
TCCA fees(4)	(419		)		—			—				—				—				(419		)
Other (expenses) income	(322		)		1			50				—				(39		)		(310		)
Income before federal income taxes	10,869				907			9,120				2,028				(2,730		)		20,194
Benefit for federal income taxes(11)	30,528				7,978			10,080				—				—				48,586
Net income	41,397				8,885			19,200				2,028				(2,730		)		68,780
Less: Net income attributable to noncontrolling interest	—				—			—				—				(11		)	(9)	(11		)
Net income attributable to Fannie Mae	$	41,397			$	8,885		$	19,200			$	2,028			$	(2,741	)		$	68,769
__________
(1)	Represents activity related to the assets and liabilities of consolidated trusts in our condensed consolidated balance sheets.
(2)	Represents the elimination of intercompany transactions occurring between the three business segments and our consolidated trusts, as well as other adjustments to reconcile to our consolidated results.
(3)	Represents the amortization expense of cost basis adjustments on securities in the Capital Markets group’s retained mortgage portfolio that on a GAAP basis are eliminated.
(4)	Includes the impact of a 10 basis point guaranty fee increase implemented pursuant to the TCCA, the incremental revenue from which must be remitted to Treasury. The resulting revenue is included in guaranty fee income and the expense is recognized as “TCCA fees.”
(5)	Represents the guaranty fees paid from consolidated trusts to the Single-Family and Multifamily segments. The adjustment to guaranty fee income in the Eliminations/Adjustments column represents the elimination of the amortization of deferred cash fees related to consolidated trusts that were re-established for segment reporting. Total guaranty fee income related to unconsolidated Fannie Mae MBS trusts and other credit enhancement arrangements is included in fee and other income in our condensed consolidated statements of operations and comprehensive income.
(6)	Primarily represents the removal of realized gains and losses on sales of Fannie Mae MBS classified as available-for-sale securities that are issued by consolidated trusts and in the Capital Markets group’s retained mortgage portfolio. The adjustment also includes the removal of securitization gains (losses) recognized in the Capital Markets segment relating to portfolio securitization transactions that do not qualify for sale accounting under GAAP.
(7)	Represents the removal of fair value adjustments on consolidated Fannie Mae MBS classified as trading that are in the Capital Markets group’s retained mortgage portfolio.
(8)	Gains from partnership investments are included in other expenses in our condensed consolidated statements of operations and comprehensive income.
(9)	Represents the adjustment from equity method of accounting to consolidated accounting for partnership investments that are consolidated in our consolidated balance sheets.
(10)	Certain prior period amounts have been reclassified to conform with the current period presentation.
(11)	Primarily represented the release of the valuation allowance for our deferred tax assets that generally is directly attributable to each segment based on the nature of the item.

Equity

Equity	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Equity	'
	Equity
	The following table displays the activity in other comprehensive income (“OCI”), net of tax, by major categories for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,								For the Six Months Ended June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Net income	$	3,667			$	10,095			$	8,992			$	68,780
	Other comprehensive income, net of tax effect:
	Changes in net unrealized gains on AFS securities (net of tax of $119 and $47, respectively, for the three months ended and net of tax of $303 and $396, respectively, for the six months ended)	221				88				561				735
	Reclassification adjustment for OTTI recognized in net income (net of tax of $8 and $2, respectively, for the three months ended and net of tax of $26 and $5, respectively, for the six months ended)	15				4				48				10
	Reclassification adjustment for gains on AFS securities included in net income (net of tax of $104 and $40, respectively, for the three months ended and net of tax of $104 and $43, respectively, for the six months ended)	(191		)		(75		)		(192		)		(80		)
	Other	—				149				—				155
	Total other comprehensive income	45				166				417				820
	Total comprehensive income	$	3,712			$	10,261			$	9,409			$	69,600
	The following table displays our accumulated other comprehensive income (“AOCI”) by major categories as of June 30, 2014 and December 31, 2013.
			As of
		June 30,						December 31,
		2014						2013
		(Dollars in millions)
	Net unrealized gains on AFS securities for which we have not recorded OTTI, net of tax		$	561					$	365
	Net unrealized gains on AFS securities for which we have recorded OTTI, net of tax		1,483						1,262
	Prior service cost and actuarial losses, net of amortization, net of tax		(395		)				(395		)
	Other losses		(29		)				(29		)
	Accumulated other comprehensive income		$	1,620					$	1,203
	The table below displays changes in accumulated other comprehensive income, net of tax, for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,																								For the Six Months Ended June 30,
		2014														2013										2014										2013
		AFS(1)						Other				Total				AFS(1)				Other(2)			Total			AFS(1)				Other			Total			AFS(1)				Other(2)			Total
			(Dollars in millions)
	Beginning balance		$	1,999				$	(424	)		$	1,575				$	1,582		$	(544	)	$	1,038			$	1,627		$	(424	)	$	1,203			$	934		$	(550	)	$	384
	OCI before reclassifications		221					—				221					88			145			233				561			—			561				735			145			880
	Amounts reclassified from OCI		(176		)			—				(176		)			(71		)	4			(67		)		(144		)	—			(144		)		(70		)	10			(60		)
	Net OCI		45					—				45					17			149			166				417			—			417				665			155			820
	Ending balance		$	2,044				$	(424	)		$	1,620				$	1,599		$	(395	)	$	1,204			$	2,044		$	(424	)	$	1,620			$	1,599		$	(395	)	$	1,204
	__________
	(1)	The amounts reclassified from AOCI represent the gain or loss recognized in earnings due to a sale of an AFS security or the recognition of a net impairment recognized in earnings, which are recorded in “Investments gains, net” and “Net other-than-temporary impairments,” respectively, in our condensed consolidated statements of operations.
	(2)	The amounts reclassified from AOCI represent activity from our defined benefit pension plans, which is recorded in “Salaries and employee benefits” in our condensed consolidated statements of operations.

Concentrations_of_Credit_Risk

Concentrations of Credit Risk	6 Months Ended
	Jun. 30, 2014
Risks and Uncertainties [Abstract]	'
Concentrations of Credit Risk	'
	Concentrations of Credit Risk
	Mortgage Sellers and Servicers.  Mortgage servicers collect mortgage and escrow payments from borrowers, pay taxes and insurance costs from escrow accounts, monitor and report delinquencies, and perform other required activities on our behalf. Our mortgage sellers and servicers are also obligated to repurchase loans or foreclosed properties, or reimburse us for losses if the foreclosed property has been sold, under certain circumstances, such as if it is determined that the mortgage loan did not meet our underwriting or eligibility requirements, if loan representations and warranties are violated or if mortgage insurers rescind coverage. Our business with mortgage servicers is concentrated. Our five largest single-family mortgage servicers, including their affiliates, serviced approximately 48% of our single-family guaranty book of business as of June 30, 2014, compared with approximately 49% as of December 31, 2013. Our ten largest multifamily mortgage servicers, including their affiliates, serviced approximately 66% of our multifamily guaranty book of business as of June 30, 2014, compared with approximately 65% as of December 31, 2013.
	If a significant mortgage seller or servicer counterparty, or a number of mortgage sellers or servicers, fails to meet their obligations to us, it could result in a significant increase in our credit losses and credit-related expense, and have a material adverse effect on our results of operations, liquidity, financial condition and net worth.
	Mortgage Insurers.  Mortgage insurance “risk in force” generally represents our maximum potential loss recovery under the applicable mortgage insurance policies. We had total mortgage insurance coverage risk in force of $104.6 billion and $102.5 billion on the single-family mortgage loans in our guaranty book of business as of June 30, 2014 and December 31, 2013, respectively, which represented 4% of our single-family guaranty book of business as of June 30, 2014 and December 31, 2013. Our primary mortgage insurance coverage risk in force was $103.6 billion and $101.4 billion as of June 30, 2014 and December 31, 2013, respectively. Our pool mortgage insurance coverage risk in force was $959 million and $1.1 billion as of June 30, 2014 and December 31, 2013, respectively. Our top four mortgage insurance companies provided 79% and 78% of our mortgage insurance as of June 30, 2014 and December 31, 2013, respectively.
	Of our largest primary mortgage insurers, PMI Mortgage Insurance Co. (“PMI”), Triad Guaranty Insurance Corporation (“Triad”) and Republic Mortgage Insurance Company (“RMIC”) are under various forms of supervised control by their state regulators and are in run-off. These three mortgage insurers provided a combined $13.5 billion, or 13%, of our risk in force mortgage insurance coverage of our single-family guaranty book of business as of June 30, 2014.
	Effective March 7, 2014, the terms of PMI’s order regarding its deferred payment arrangements changed to increase its cash payments on policyholder claims from 55% to 67%. In addition, PMI has paid us sufficient amounts of its outstanding deferred payment obligations to bring payment on our claims to 67%. It is uncertain whether PMI will be permitted in the future to pay any remaining deferred policyholder claims and/or increase or decrease the amount of cash they pay on claims.
	Effective July 1, 2014, the terms of RMIC’s order regarding its deferred payment arrangements changed to no longer defer payments on policyholder claims and to increase its cash payments from 60% to 100%. In addition, RMIC has paid us sufficient amounts of its outstanding deferred payment obligations to bring payment on our claims to 100%. Even though RMIC is no longer deferring payments on policyholder claims, RMIC remains in run-off and under the supervisory control of the North Carolina Department of Insurance.
	Although the financial condition of our mortgage insurer counterparties currently approved to write new business has improved, there is still risk that our mortgage insurer counterparties may fail to fulfill their obligations to reimburse us for claims under insurance policies. If we determine that it is probable that we will not collect all of our claims from one or more of these mortgage insurer counterparties, it could result in an increase in our loss reserves, which could adversely affect our results of operations, liquidity, financial condition and net worth.
	When we estimate the credit losses that are inherent in our mortgage loans and under the terms of our guaranty obligations we also consider the recoveries that we will receive on primary mortgage insurance, as mortgage insurance recoveries would reduce the severity of the loss associated with defaulted loans. We evaluate the financial condition of our mortgage insurer counterparties and adjust the contractually due recovery amounts to ensure that only probable losses as of the balance sheet date are included in our loss reserve estimate. As a result, if our assessment of one or more of our mortgage insurer counterparties’ ability to fulfill their respective obligations to us worsens, it could result in an increase in our loss reserves.
	The following table displays the amount by which our estimated benefit from mortgage insurance as of June 30, 2014 and December 31, 2013 reduced our total loss reserves as of those dates.
		As of
		June 30, 2014			December 31, 2013
			(Dollars in millions)
	Contractual mortgage insurance benefit		$	5,886		$	6,751
	Less: Collectibility adjustment(1)		354			431
	Estimated benefit included in total loss reserves		$	5,532		$	6,320
	__________
	(1)	Represents an adjustment that reduces the contractual benefit for our assessment of our mortgage insurer counterparties’ inability to fully pay the contractual mortgage insurance claims.
	We had outstanding receivables of $2.0 billion recorded in “Other assets” in our condensed consolidated balance sheets as of June 30, 2014 and $2.1 billion as of December 31, 2013 related to amounts claimed on insured, defaulted loans excluding government insured loans. Of this amount, $328 million as of June 30, 2014 and $402 million as of December 31, 2013 was due from our mortgage sellers or servicers. We assessed the total outstanding receivables for collectibility, and they are recorded net of a valuation allowance of $611 million as of June 30, 2014 and $655 million as of December 31, 2013. The valuation allowance reduces our claim receivable to the amount which is considered probable of collection as of June 30, 2014 and December 31, 2013.
	For information on credit risk associated with our derivative transactions and repurchase agreements refer to “Note 9, Derivative Instruments” and “Note 15, Netting Arrangements.”

Netting_Arrangements

Netting Arrangements	6 Months Ended
	Jun. 30, 2014
Offsetting [Abstract]	'
Netting Arrangements	'
	Netting Arrangements
	We use master netting arrangements, which allow us to offset certain financial instruments and collateral with the same counterparty, to minimize counterparty credit exposure. The table below displays information related to derivatives and securities purchased under agreements to resell or similar arrangements which are subject to an enforceable master netting arrangement that are either offset or not offset in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013.
			As of June 30, 2014
										Net Amount Presented in the Condensed Consolidated Balance Sheets						Amounts Not Offset in the Condensed Consolidated Balance Sheets
			Gross Amount			Gross Amount Offset(1)										Financial Instruments(2)				Collateral (3)				Net Amount
			(Dollars in millions)
	Assets:
	OTC risk management derivatives		$	6,795			$	(6,777	)		$	18					$	—			$	(12	)		$	6
	OTC-cleared risk management derivatives (4)		949				(120		)		829						—				—				829
	Mortgage commitment derivatives		389				—				389						(145		)		(4		)		240
	Total derivative assets		8,133				(6,897		)		1,236			(5	)		(145		)		(16		)		1,075
	Securities purchased under agreements to resell or similar arrangements(6)		32,250				—				32,250						—				(32,249		)		1
	Total assets		$	40,383			$	(6,897	)		$	33,486					$	(145	)		$	(32,265	)		$	1,076
	Liabilities:
	OTC risk management derivatives		$	(8,352	)		$	8,142			$	(210	)				$	—			$	—			$	(210	)
	OTC-cleared risk management derivatives (4)		(1,248		)		1,248				—						—				—				—
	Mortgage commitment derivatives		(525		)		—				(525		)				145				—				(380		)
	Total liabilities		$	(10,125	)		$	9,390			$	(735	)	(5	)		$	145			$	—			$	(590	)
			As of December 31, 2013
										Net Amount Presented in the Condensed Consolidated Balance Sheets						Amounts Not Offset in the Condensed Consolidated Balance Sheets
			Gross Amount			Gross Amount Offset(1)										Financial Instruments (2)				Collateral(3)				Net Amount
			(Dollars in millions)
	Assets:
	OTC risk management derivatives		$	8,491			$	(8,422	)		$	69					$	—			$	(20	)		$	49
	Mortgage commitment derivatives		265				—				265						(83		)		—				182
	Total derivative assets		8,756				(8,422		)		334			(5	)		(83		)		(20		)		231
	Securities purchased under agreements to resell or similar arrangements(6)		50,565				—				50,565						—				(50,565		)		—
	Total assets		$	59,321			$	(8,422	)		$	50,899					$	(83	)		$	(50,585	)		$	231
	Liabilities:
	OTC risk management derivatives		$	(9,503	)		$	9,370			$	(133	)				$	—			$	—			$	(133	)
	Mortgage commitment derivatives		(214		)		—				(214		)				83				—				(131		)
	Total liabilities		$	(9,717	)		$	9,370			$	(347	)	(5	)		$	83			$	—			$	(264	)
	__________
	(1)	Represents the effect of the right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received and accrued interest.
	(2)	Mortgage commitment derivative amounts reflect where we have recognized both an asset and a liability with the same counterparty under an enforceable master netting arrangement but we have not elected to offset the related amounts in our condensed consolidated balance sheets.
	(3)	Represents collateral posted or received that has neither been recognized nor offset in our condensed consolidated balance sheets. Does not include collateral held in excess of our exposure.
	(4) As of June 30, 2014, we net OTC-cleared derivative assets and derivative liabilities where we have enforceable master netting arrangements.
	(5)	Excludes derivative assets of $28 million and $1.7 billion and derivative liabilities of $1 million and $1.1 billion recognized in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively, that are not subject to enforceable master netting arrangements.
	(6)	Includes $15.6 billion and $11.6 billion of securities purchased under agreements to resell or similar arrangements classified as “Cash and cash equivalents” in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively.
	Derivative instruments are recorded at fair value and securities purchased under agreements to resell or similar arrangements are recorded at amortized cost in our condensed consolidated balance sheets. The fair value of non-cash collateral accepted for OTC risk management derivatives was $12 million and $24 million as of June 30, 2014 and December 31, 2013, respectively. The fair value of non-cash collateral accepted for securities purchased under agreements to resell or similar arrangements was $32.3 billion and $50.7 billion, of which $29.0 billion and $39.8 billion could be sold or repledged as of June 30, 2014 and December 31, 2013, respectively. None of the underlying collateral was sold or repledged as of June 30, 2014 and December 31, 2013.
	We determine our rights to offset the assets and liabilities presented above with the same counterparty, including collateral posted or received, based on the contractual arrangements entered into with our individual counterparties and various rules and regulations that would govern the insolvency of a derivative counterparty. The following is a description, under various agreements, of the nature of those rights and their effect or potential effect on our financial position.
	The terms of the majority of our contracts for OTC risk management derivatives are governed under master agreements of the International Swaps and Derivatives Association Inc. (“ISDA”). These agreements provide that all transactions entered into under the agreement with the counterparty constitute a single contractual relationship. An event of default by the counterparty allows the early termination of all outstanding transactions under the same ISDA agreement and we may offset all outstanding amounts related to the terminated transactions including collateral posted or received.
	The terms of our contracts for OTC-cleared derivatives are governed under the rules of the clearing organization and the agreement between us and the clearing member of that clearing organization. In the event of a clearing organization default, all open positions at the clearing organization are closed and a net position is calculated. Unless otherwise transferred, in the event of a clearing member default, all open positions cleared through that clearing member are closed and a net position is calculated.
	The terms of our contracts for mortgage commitment derivatives are primarily governed by the Fannie Mae Single-Family Selling Guide (“Guide”), for Fannie Mae-approved lenders, or Master Securities Forward Transaction Agreements (“MSFTA”), for counterparties that are not Fannie Mae-approved lenders. In the event of default by the counterparty, both the Guide and the MSFTA allow us to terminate all outstanding transactions under the applicable agreement and offset all outstanding amounts related to the terminated transactions including collateral posted or received. In addition, under the Guide, upon a lender event of default, we generally may offset any amounts owed to a lender against any amounts a lender may owe us under any other existing agreement, regardless of whether or not such other agreements are in default or payments are immediately due.
	The terms of our contracts for securities purchased under agreements to resell and securities sold under agreements to repurchase are governed by Master Repurchase Agreements, which are based on the guidelines prescribed by the Securities Industry and Financial Markets Association. Master Repurchase Agreements provide that all transactions under the agreement constitute a single contractual relationship. An event of default by the counterparty allows the early termination of all outstanding transactions under the same agreement and we may offset all outstanding amounts related to the terminated transactions including collateral posted or received.
	We also have securities purchased under agreements to resell which we transact through the Fixed Income Clearing Corporation (“FICC”). Under the rules of the FICC, all agreements for securities purchased under agreements to resell that are submitted to the FICC for clearing become transactions with the FICC that are subject to FICC clearing rules. In the event of a FICC default, all open positions at the FICC are closed and a net position is calculated.

Fair_Value

Fair Value	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value	'
	Fair Value
	We use fair value measurements for the initial recording of certain assets and liabilities and periodic remeasurement of certain assets and liabilities on a recurring or nonrecurring basis.
	Fair Value Measurement
	Fair value measurement guidance defines fair value, establishes a framework for measuring fair value and sets forth disclosures around fair value measurements. This guidance applies whenever other accounting guidance requires or permits assets or liabilities to be measured at fair value. The guidance establishes a three-level fair value hierarchy that prioritizes the inputs into the valuation techniques used to measure fair value. The fair value hierarchy gives the highest priority, Level 1, to measurements based on unadjusted quoted prices in active markets for identical assets or liabilities. The next highest priority, Level 2, is given to measurements of assets and liabilities based on limited observable inputs or observable inputs for similar assets and liabilities. The lowest priority, Level 3, is given to measurements based on unobservable inputs.
	Recurring Changes in Fair Value
	The following tables display our assets and liabilities measured in our condensed consolidated balance sheets at fair value on a recurring basis subsequent to initial recognition, including instruments for which we have elected the fair value option as of June 30, 2014 and December 31, 2013.
			Fair Value Measurements as of June 30, 2014
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)						Netting Adjustment(1)						Estimated Fair Value
			(Dollars in millions)
	Recurring fair value measurements:
	Assets:
	Trading securities:
	Mortgage-related securities:
	Fannie Mae		$	—					$	5,686					$	—					$	—					$	5,686
	Freddie Mac		—						1,766						—						—						1,766
	Ginnie Mae		—						234						—						—						234
	Alt-A private-label securities		—						551						643						—						1,194
	Subprime private-label securities		—						—						1,282						—						1,282
	CMBS		—						2,641						—						—						2,641
	Mortgage revenue bonds		—						—						643						—						643
	Other		—						—						101						—						101
	Non-mortgage-related securities:
	U.S. Treasury securities		13,083						—						—						—						13,083
	Total trading securities		13,083						10,878						2,669						—						26,630
	Available-for-sale securities:
	Mortgage-related securities:
	Fannie Mae		—						6,020						2						—						6,022
	Freddie Mac		—						6,193						9						—						6,202
	Ginnie Mae		—						528						—						—						528
	Alt-A private-label securities		—						2,964						3,717						—						6,681
	Subprime private-label securities		—						—						5,705						—						5,705
	CMBS		—						1,508						—						—						1,508
	Mortgage revenue bonds		—						—						4,560						—						4,560
	Other		—						3						2,817						—						2,820
	Total available-for-sale securities		—						17,216						16,810						—						34,026
	Mortgage loans of consolidated trusts		—						12,585						2,531						—						15,116
	Other assets:
	Risk management derivatives:
	Swaps		—						7,347						86						—						7,433
	Swaptions		—						310						—						—						310
	Other		—						—						29						—						29
	Netting adjustment		—						—						—						(6,897		)				(6,897		)
	Mortgage commitment derivatives		—						365						24						—						389
	Total other assets		—						8,022						139						(6,897		)				1,264
	Total assets at fair value		$	13,083					$	48,701					$	22,149					$	(6,897	)				$	77,036
			Fair Value Measurements as of June 30, 2014
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)						Netting Adjustment(1)							Estimated Fair Value
			(Dollars in millions)
	Liabilities:
	Long-term debt:
	Of Fannie Mae:
	Senior floating		$	—					$	3,107					$	325					$	—					$	3,432
	Total of Fannie Mae		—						3,107						325						—						3,432
	Of consolidated trusts		—						15,922						498						—						16,420
	Total long-term debt		—						19,029						823						—						19,852
	Other liabilities:
	Risk management derivatives:
	Swaps		—						8,497						118						—						8,615
	Swaptions		—						985						—						—						985
	Other		—						—						1						—						1
	Netting adjustment		—						—						—						(9,390		)				(9,390		)
	Mortgage commitment derivatives		—						525						—						—						525
	Total other liabilities		—						10,007						119						(9,390		)				736
Total liabilities at fair value		$	—					$	29,036					$	942					$	(9,390	)				$	20,588
		Fair Value Measurements as of December 31, 2013
	Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Netting Adjustment(1)						Estimated Fair Value
													(Level 3)
		(Dollars in millions)
Assets:
Trading securities:
Mortgage-related securities:
Fannie Mae		$	—					$	5,828					$	42					$	—					$	5,870
Freddie Mac		—						1,837						2						—						1,839
Ginnie Mae		—						407						—						—						407
Alt-A private-label securities		—						898						618						—						1,516
Subprime private-label securities		—						—						1,448						—						1,448
CMBS		—						2,718						—						—						2,718
Mortgage revenue bonds		—						—						565						—						565
Other		—						—						99						—						99
Non-mortgage-related securities:
U.S. Treasury securities		16,306						—						—						—						16,306
Total trading securities		16,306						11,688						2,774						—						30,768
Available-for-sale securities:
Mortgage-related securities:
Fannie Mae		—						6,566						7						—						6,573
Freddie Mac		—						6,834						8						—						6,842
Ginnie Mae		—						588						—						—						588
Alt-A private-label securities		—						3,558						3,791						—						7,349
Subprime private-label securities		—						—						7,068						—						7,068
CMBS		—						1,606						—						—						1,606
Mortgage revenue bonds		—						3						5,253						—						5,256
Other		—						4						2,885						—						2,889
Total available-for-sale securities		—						19,159						19,012						—						38,171
Mortgage loans of consolidated trusts		—						11,564						2,704						—						14,268
Other assets:
Risk management derivatives:
Swaps		—						9,604						36						—						9,640
Swaptions		—						561						1						—						562
Other		—						—						28						—						28
Netting adjustment		—						—						—						(8,422		)				(8,422		)
Mortgage commitment derivatives		—						265						—						—						265
Total other assets		—						10,430						65						(8,422		)				2,073
Total assets at fair value		$	16,306					$	52,841					$	24,555					$	(8,422	)				$	85,280
		Fair Value Measurements as of December 31, 2013
	Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Netting Adjustment(1)						Estimated Fair Value
													(Level 3)
		(Dollars in millions)
Liabilities:
Long-term debt:
Of Fannie Mae:
Senior fixed		$	—					$	353					$	—					$	—					$	353
Senior floating		—						—						955						—						955
Total of Fannie Mae		—						353						955						—						1,308
Of consolidated trusts		—						14,458						518						—						14,976
Total long-term debt		—						14,811						1,473						—						16,284
Other liabilities:
Risk management derivatives:
Swaps		—						9,444						96						—						9,540
Swaptions		—						1,084						—						—						1,084
Other		—						—						1						—						1
Netting adjustment		—						—						—						(9,370		)				(9,370		)
Mortgage commitment derivatives		—						206						8						—						214
Total other liabilities		—						10,734						105						(9,370		)				1,469
Total liabilities at fair value		$	—					$	25,545					$	1,578					$	(9,370	)				$	17,753
__________
(1)	Derivative contracts are reported on a gross basis by level. The netting adjustment represents the effect of the legal right to offset under legally enforceable master netting agreements to settle with the same counterparty on a net basis, including cash collateral posted and received.
The following tables display a reconciliation of all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2014 and 2013. The tables also display gains and losses due to changes in fair value, including both realized and unrealized gains and losses, recognized in our condensed consolidated statements of operations and comprehensive income for Level 3 assets and liabilities for the three and six months ended June 30, 2014 and 2013. When assets and liabilities are transferred between levels, we recognize the transfer as of the end of the period.
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Three Months Ended June 30, 2014
					Total Gains or (Losses)																																			Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2014(5)
					(Realized/Unrealized)
	Balance, March 31, 2014				Included in Net Income				Included in						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance,
									Other Comprehensive																									Level 3(4)			30-Jun-14
									Income(1)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Alt-A private-label securities	$	655			$	84				$	—				$	—			$	(23	)		$	—			$	(22	)		$	(67	)	$	16		$	643			$	84
Subprime private-label securities	1,453				103					—					—				(241		)		—				(33		)		—			—			1,282				204
Mortgage revenue bonds	601				44					—					—				—				—				(2		)		—			—			643				44
Other	102				4					—					—				—				—				(5		)		—			—			101				4
Total trading securities	$	2,811			$	235				$	—				$	—			$	(264	)		$	—			$	(62	)		$	(67	)	$	16		$	2,669			$	336
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	5			$	—				$	—				$	—			$	—			$	—			$	(1	)		$	(4	)	$	2		$	2			$	—
Freddie Mac	8				—					—					—				—				—				—				—			1			9				—
Alt-A private-label securities	3,570				103					(24		)			—				(320		)		—				(111		)		(265		)	764			3,717				—
Subprime private-label securities	7,030				268					(38		)			—				(1,349		)		—				(206		)		—			—			5,705				—
Mortgage revenue bonds	5,006				(7		)			87					—				(39		)		—				(487		)		—			—			4,560				—
Other	2,844				3					54					—				—				—				(84		)		—			—			2,817				—
Total available-for-sale securities	$	18,463			$	367				$	79				$	—			$	(1,708	)		$	—			$	(889	)		$	(269	)	$	767		$	16,810			$	—
Mortgage loans of consolidated trusts	$	2,608			$	102				$	—				$	7			$	—			$	—			$	(85	)		$	(165	)	$	64		$	2,531			$	86
Net derivatives	(23		)		47					—					—				—				—				(4		)		—			—			20				41
Long-term debt:
Of Fannie Mae:
Senior floating	$	(310	)		$	(15	)			$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(325	)		$	(15	)
Of consolidated trusts	(506		)		(33		)			—					—				—				(1		)		17				47			(22		)	(498		)		(31		)
Total long-term debt	$	(816	)		$	(48	)			$	—				$	—			$	—			$	(1	)		$	17			$	47		$	(22	)	$	(823	)		$	(46	)
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Six Months Ended June 30, 2014
					Total (Losses) or Gains (Realized/Unrealized)																																			Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2014(5)
	Balance, December 31, 2013				Included in Net Income				Included in						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance,
									Other Comprehensive																									Level 3(4)			30-Jun-14
									Income(1)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Fannie Mae	$	42			$	(1	)			$	—				$	—			$	—			$	—			$	(2	)		$	(39	)	$	—		$	—			$	—
Freddie Mac	2				—					—					—				—				—				—				(2		)	—			—				—
Alt-A private-label securities	618				103					—					—				(23		)		—				(38		)		(143		)	126			643				101
Subprime private-label securities	1,448				179					—					—				(241		)		—				(104		)		—			—			1,282				280
Mortgage revenue bonds	565				84					—					—				—				—				(6		)		—			—			643				84
Other	99				9					—					—				—				—				(7		)		—			—			101				9
Total trading securities	$	2,774			$	374				$	—				$	—			$	(264	)		$	—			$	(157	)		$	(184	)	$	126		$	2,669			$	474
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	7			$	—				$	—				$	—			$	—			$	—			$	(1	)		$	(6	)	$	2		$	2			$	—
Freddie Mac	8				—					—					—				—				—				—				—			1			9				—
Alt-A private-label securities	3,791				116					49					—				(320		)		—				(199		)		(874		)	1,154			3,717				—
Subprime private-label securities	7,068				301					181					—				(1,349		)		—				(496		)		—			—			5,705				—
Mortgage revenue bonds	5,253				(27		)			280					—				(58		)		—				(888		)		—			—			4,560				—
Other	2,885				6					95					—				—				—				(169		)		—			—			2,817				—
Total available-for-sale securities	$	19,012			$	396				$	605				$	—			$	(1,727	)		$	—			$	(1,753	)		$	(880	)	$	1,157		$	16,810			$	—
Mortgage loans of consolidated trusts	$	2,704			$	127				$	—				$	31			$	—			$	—			$	(166	)		$	(313	)	$	148		$	2,531			$	94
Net derivatives	(40		)		77					—					—				—				—				(16		)		(1		)	—			20				54
Long-term debt:
Of Fannie Mae:
Senior floating	$	(955	)		$	(105	)			$	—				$	—			$	—			$	(750	)		$	20			$	1,465		$	—		$	(325	)		$	(59	)
Of consolidated trusts	(518		)		(34		)			—					—				—				(1		)		35				66			(46		)	(498		)		(32		)
Total long-term debt	$	(1,473	)		$	(139	)			$	—				$	—			$	—			$	(751	)		$	55			$	1,531		$	(46	)	$	(823	)		$	(91	)
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Three Months Ended June 30, 2013
					Total (Losses) or Gains or (Realized/Unrealized)																																			Net Unrealized (Losses) Gains Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2013(5)
	Balance, March 31,				Included in Net Income				Included in Other Comprehensive Income(1)						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance, June 30, 2013
	2013																																	Level 3(4)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Fannie Mae	$	61			$	(3	)			$	—				$	—			$	—			$	—			$	(6	)		$	—		$	—		$	52			$	(3	)
Freddie Mac	2				—					—					—				—				—				—				—			—			2				—
Ginnie Mae	—				—					—					—				—				—				—				—			2			2				—
Alt-A private-label securities	464				32					—					—				—				—				(39		)		(162		)	408			703				31
Subprime private-label securities	1,446				80					—					—				—				—				(38		)		—			—			1,488				79
Mortgage revenue bonds	661				(56		)			—					—				—				—				(2		)		—			—			603				(56		)
Other	118				(6		)			—					—				—				—				(3		)		—			—			109				(6		)
Total trading securities	$	2,752			$	47				$	—				$	—			$	—			$	—			$	(88	)		$	(162	)	$	410		$	2,959			$	45
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	12			$	—				$	(1	)			$	—			$	—			$	—			$	(1	)		$	—		$	—		$	10			$	—
Freddie Mac	9				—					(1		)			—				—				—				—				—			1			9				—
Alt-A private-label securities	6,112				11					249					—				—				—				(401		)		(773		)	1,810			7,008				—
Subprime private-label securities	7,868				46					234					—				—				—				(286		)		—			—			7,862				—
Mortgage revenue bonds	7,351				12					(253		)			—				—				—				(710		)		—			—			6,400				—
Other	3,099				1					55					—				—				—				(104		)		—			—			3,051				—
Total available-for-sale securities	$	24,451			$	70				$	283				$	—			$	—			$	—			$	(1,502	)		$	(773	)	$	1,811		$	24,340			$	—
Mortgage loans of consolidated trusts	$	2,882			$	30				$	—				$	85			$	—			$	—			$	(122	)		$	(51	)	$	137		$	2,961			$	25
Net derivatives	(7		)		(89		)			—					—				—				—				31				16			—			(49		)		(44		)
Long-term debt:
Of Fannie Mae:
Senior floating	$	(383	)		$	46				$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(337	)		$	46
Of consolidated trusts	(1,077		)		(66		)			—					—				—				(5		)		56				57			(42		)	(1,077		)		(69		)
Total long-term debt	$	(1,460	)		$	(20	)			$	—				$	—			$	—			$	(5	)		$	56			$	57		$	(42	)	$	(1,414	)		$	(23	)
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Six Months Ended June 30, 2013
					Total (Losses) or Gains or (Realized/Unrealized)																																			Net Unrealized (Losses) Gains Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2013(5)
	Balance, December 31,				Included in Net Income				Included in Other Comprehensive Income(1)						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance, June 30, 2013
	2012																																	Level 3(4)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Fannie Mae	$	68			$	(6	)			$	—				$	—			$	—			$	—			$	(10	)		$	—		$	—		$	52			$	(6	)
Freddie Mac	2				—					—					—				—				—				—				—			—			2				—
Ginnie Mae	1				—					—					—				—				—				(1		)		—			2			2				—
Alt-A private-label securities	104				127					—					—				—				—				(55		)		(206		)	733			703				121
Subprime private-label securities	1,319				239					—					—				—				—				(70		)		—			—			1,488				239
Mortgage revenue bonds	675				(69		)			—					—				—				—				(3		)		—			—			603				(69		)
Other	117				(4		)			—					—				—				—				(4		)		—			—			109				(4		)
Total trading securities	$	2,286			$	287				$	—				$	—			$	—			$	—			$	(143	)		$	(206	)	$	735		$	2,959			$	281
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	29			$	—				$	(1	)			$	—			$	—			$	—			$	(4	)		$	(14	)	$	—		$	10			$	—
Freddie Mac	10				—					(1		)			—				—				—				(1		)		—			1			9				—
Alt-A private-label securities	6,564				20					467					—				—				—				(669		)		(1,965		)	2,591			7,008				—
Subprime private-label securities	7,447				90					911					—				—				—				(586		)		—			—			7,862				—
Mortgage revenue bonds	7,837				10					(282		)			—				(19		)		—				(1,146		)		—			—			6,400				—
Other	3,147				5					99					—				—				—				(200		)		—			—			3,051				—
Total available-for-sale securities	$	25,034			$	125				$	1,193				$	—			$	(19	)		$	—			$	(2,606	)		$	(1,979	)	$	2,592		$	24,340			$	—
Mortgage loans of consolidated trusts	$	2,634			$	57				$	—				$	243			$	—			$	—			$	(234	)		$	(89	)	$	350		$	2,961			$	(393	)
Net derivatives	14				(129		)			—					—				—				—				54				16			(4		)	(49		)		(61		)
Long-term debt:
Of Fannie Mae:
Senior floating	$	(400	)		$	63				$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(337	)		$	63
Of consolidated trusts	(1,128		)		(120		)			—					—				—				(20		)		105				170			(84		)	(1,077		)		245
Total long-term debt	$	(1,528	)		$	(57	)			$	—				$	—			$	—			$	(20	)		$	105			$	170		$	(84	)	$	(1,414	)		$	308
__________
(1)	Gains (losses) included in other comprehensive income are included in “Changes in unrealized gains on available-for-sale securities, net of reclassification adjustments and taxes” in the condensed consolidated statements of operations and comprehensive income.
(2)	Purchases and sales include activity related to the consolidation and deconsolidation of assets of securitization trusts.
(3)	Issues and settlements include activity related to the consolidation and deconsolidation of liabilities of securitization trusts.
(4)	Transfers out of Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans and credit risk sharing securities issued under our Connecticut Avenue Securities series. Prices for these securities were obtained from multiple third-party vendors or dealers supported by market observable inputs. Transfers into Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans. Prices for these securities are based on inputs from a single source or inputs that were not readily observable.
(5)	Amount represents temporary changes in fair value. Amortization, accretion and other-than-temporary impairments are not considered unrealized and are not included in this amount.
The following tables display realized and unrealized gains and losses included in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013, for our Level 3 assets and liabilities measured in our condensed consolidated balance sheets at fair value on a recurring basis.
		For the Three Months Ended June 30, 2014
	Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
		(Dollars in millions)
Total realized and unrealized gains (losses) included in net income		$	70					$	329					$	(19	)				$	323					$	703
Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2014		$	—					$	417					$	—					$	—					$	417
		For the Six Months Ended June 30, 2014
	Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
		(Dollars in millions)
Total realized and unrealized gains (losses) included in net income		$	140					$	435					$	(64	)				$	324					$	835
Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2014		$	—					$	531					$	—					$	—					$	531
		For the Three Months Ended June 30, 2013
	Interest Income						Fair Value (Losses) Gains, net						Net OTTI						Other						Total
		(Dollars in millions)
Total realized and unrealized gains (losses) included in net income		$	70					$	(31	)				$	(4	)				$	3					$	38
Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2013		$	—					$	3					$	—					$	—					$	3
		For the Six Months Ended June 30, 2013
	Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
		(Dollars in millions)
Total realized and unrealized gains (losses) included in net income		$	125					$	161					$	(9	)				$	6					$	283
Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2013		$	—					$	135					$	—					$	—					$	135
Nonrecurring Changes in Fair Value
The following tables display assets measured in our condensed consolidated balance sheets at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when we evaluate loans for impairment) as of June 30, 2014 and December 31, 2013.
		Fair Value Measurements as of June 30, 2014
	Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Estimated Fair Value
													(Level 3)
		(Dollars in millions)
Nonrecurring fair value measurements:
Assets:
Mortgage loans held for sale, at lower of cost or fair value		$	—					$	89					$	151					$	240
Single-family mortgage loans held for investment, at amortized cost:(1)
Of Fannie Mae		—						—						17,189						17,189
Of consolidated trusts		—						—						53						53
Multifamily mortgage loans held for investment, at amortized cost		—						—						1,033						1,033
Acquired property, net:
Single-family		—						—						4,300						4,300
Multifamily		—						—						163						163
Other assets		—						—						113						113
Total nonrecurring fair value measurements		$	—					$	89					$	23,002					$	23,091
		Fair Value Measurements as of December 31, 2013
	Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Estimated Fair Value
													(Level 3)
	(Dollars in millions)
Assets:
Mortgage loans held for sale, at lower of cost or fair value		$	—					$	101					$	132					$	233
Single-family mortgage loans held for investment, at amortized cost:(1)
Of Fannie Mae		—						—						19,966						19,966
Of consolidated trusts		—						—						79						79
Multifamily mortgage loans held for investment, at amortized cost		—						—						1,533						1,533
Acquired property, net:
Single-family		—						—						4,041						4,041
Multifamily		—						—						98						98
Other assets		—						—						121						121
Total nonrecurring fair value measurements		$	—					$	101					$	25,970					$	26,071
_________
(1)	Excludes estimated recoveries from mortgage insurance proceeds.
The following table displays valuation techniques and the range and the weighted average of significant unobservable inputs for our Level 3 assets and liabilities measured at fair value on a recurring basis as of June 30, 2014 and December 31, 2013.
		Fair Value Measurements as of June 30, 2014
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
		(Dollars in millions)
Recurring fair value measurements:
Trading securities:
Mortgage-related securities:
Alt-A private-label securities(3)		$	67			Consensus		Default Rate (%)		4.2					4.2
								Prepayment Speed (%)		2.2					2.2
								Severity (%)		47.1					47.1
								Spreads (bps)		240.6					240.6
		158				Consensus
		381				Discounted Cash Flow		Default Rate (%)		4.2		-	8.8		7.7
								Prepayment Speed (%)		2.2		-	5.1		3.4
								Severity (%)		47.1		-	85.3		75.5
								Spreads (bps)		247.5		-	300		266.5
		37				Other
Total Alt-A private-label securities		643
Subprime private-label securities(3)		198				Single Vendor
		416				Consensus		Default Rate (%)		3.7		-	11.2		7.8
								Prepayment Speed (%)		0.2		-	4.1		1.5
								Severity (%)		71.7		-	95		80.6
								Spreads (bps)		245		-	345		272.7
		549				Consensus
		119				Other
Total subprime private-label securities		1,282
Mortgage revenue bonds		464				Discounted Cash Flow		Spreads (bps)		103.1		-	435		322.1
		179				Other
Total mortgage revenue bonds		643
Other		101				Discounted Cash Flow		Spreads (bps)		445					445
Total trading securities		$	2,669
		Fair Value Measurements as of June 30, 2014
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
		(Dollars in millions)
Available-for-sale securities:
Mortgage-related securities:
Agency(2)		$	11			Other
Alt-A private-label securities(3)		454				Single Vendor		Default Rate (%)		2.2		-	5.7		3.9
								Prepayment Speed (%)		1.6		-	20.7		7.1
								Severity (%)		14.2		-	95		54.6
								Spreads (bps)		156.3		-	320		239
		1,254				Consensus		Default Rate (%)		0.9		-	16.7		5.2
								Prepayment Speed (%)		0		-	36.8		10.1
								Severity (%)		27.8		-	95		69.7
								Spreads (bps)		170		-	224.6		220.1
		844				Consensus
		812				Discounted Cash Flow		Default Rate (%)		2		-	11.8		5.3
								Prepayment Speed (%)		0.6		-	8.7		6.1
								Severity (%)		24.7		-	95		51.1
								Spreads (bps)		146		-	350		242.5
		353				Other
Total Alt-A private-label securities		3,717
Subprime private-label securities (3)		347				Single Vendor
		2,020				Consensus		Default Rate (%)		1.8		-	20.6		6.3
								Prepayment Speed (%)		0.1		-	19.8		2.9
								Severity (%)		28		-	95		84.3
								Spreads (bps)		135		-	245		197.4
		2,846				Consensus
		492				Other
Total subprime private-label securities		5,705
Mortgage revenue bonds		2,155				Single Vendor		Spreads (bps)		0		-	324.6		58.2
		647				Single Vendor
		1,677				Discounted Cash Flow		Spreads (bps)		0		-	592.9		327.2
		81				Other
Total mortgage revenue bonds		4,560
Other		493				Consensus		Default Rate (%)		3.1		-	5		4.7
								Prepayment Speed (%)		2		-	9.8		3.7
								Severity (%)		0.2		-	85		71.6
								Spreads (bps)		195		-	745		336.3
		329				Consensus
		855				Discounted Cash Flow		Default Rate (%)		0		-	5		1
								Prepayment Speed (%)		0		-	8.8		1.4
								Severity (%)		0		-	85		8.4
								Spreads (bps)		220		-	445		351.4
		1,140				Other
Total Other		2,817
Total available-for-sale securities		$	16,810
		Fair Value Measurements as of June 30, 2014
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
		(Dollars in millions)
Mortgage loans of consolidated trusts:
Single-family		$	1,634			Build-Up		Default Rate (%)		0.1		-	97.6		14.7
								Prepayment Speed (%)		2.8		-	45.7		17.2
								Severity (%)		0		-	100		27.4
		237				Consensus
		408				Discounted Cash Flow		Default Rate (%)		1		-	14.6		5
								Prepayment Speed (%)		0.2		-	17.5		7.9
								Severity (%)		38.4		-	95		56.4
								Spreads (bps)		135		-	595		192.3
		72				Other
Total single-family		2,351
Multifamily		180				Build-Up		Spreads (bps)		46		-	286.4		115.2
Total mortgage loans of consolidated trusts		$	2,531
Net derivatives		$	(89	)		Internal Model
		85				Dealer Mark
		24				Other
Total net derivatives		$	20
Long-term debt:
Of Fannie Mae:
Senior floating		$	(325	)		Discounted Cash Flow
Total of Fannie Mae		(325		)
Of consolidated trusts		(216		)		Consensus
Of consolidated trusts		(139		)		Discounted Cash Flow		Default Rate (%)		1		-	10.2		3.4
								Prepayment Speed (%)		0.2		-	100		23.9
								Severity (%)		38.4		-	95		44.8
								Spreads (bps)		64		-	595		208.8
		(143		)		Other
Total of consolidated trusts		(498		)
Total long-term debt		$	(823	)
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)				Weighted - Average(1)
		(Dollars in millions)
Recurring fair value measurements:
Trading securities:
Mortgage-related securities:
Agency(2)		$	44			Other
Alt-A private-label securities(3)		60				Single Vendor		Default Rate (%)		6	-	10.8		8.7
								Prepayment Speed (%)		4.1	-	5.4		4.6
								Severity (%)		76.1	-	92.7		83.1
								Spreads (bps)		414.3	-	421.7		417.5
		325				Consensus		Default Rate (%)		6.9	-	10.4		8.9
								Prepayment Speed (%)		1.9	-	2.5		2.2
								Severity (%)		77.3	-	97.8		88.7
								Spreads (bps)		298.3	-	420.2		366.3
		85				Consensus
		148				Discounted Cash Flow		Default Rate (%)		4	-	6.9		6.5
								Prepayment Speed (%)		1.9	-	3.4		2.2
								Severity (%)		42.7	-	77.3		67.6
								Spreads (bps)		325.4	-	439.4		418.6
Total Alt-A private-label securities		618
Subprime private-label securities(3)		113				Single Vendor		Default Rate (%)		3.1	-	7.5		3.9
								Prepayment Speed (%)		1.8	-	2.5		2
								Severity (%)		75	-	87.2		75.8
								Spreads (bps)		325				325
		77				Single Vendor
		400				Consensus		Default Rate (%)		3	-	9.2		6.4
								Prepayment Speed (%)		1.4	-	2.2		1.9
								Severity (%)		50.4	-	87.2		74.4
								Spreads (bps)		325	-	425		353
		808				Consensus
		50				Discounted Cash Flow		Default Rate (%)		6.9				6.9
								Prepayment Speed (%)		0.1				0.1
								Severity (%)		75				75
								Spreads (bps)		325				325
Total subprime private-label securities		1,448
Mortgage revenue bonds		539				Discounted Cash Flow		Spreads (bps)		35	-	440		340.6
		26				Other
Total mortgage revenue bonds		565
Other		99				Discounted Cash Flow		Spreads (bps)		525				525
Total trading securities		$	2,774
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)				Weighted - Average(1)
		(Dollars in millions)
Available-for-sale securities:
Mortgage-related securities:
Agency(2)		$	15			Other
Alt-A private-label securities(3)		139				Single Vendor		Default Rate (%)		0.9	-	6.4		3.9
								Prepayment Speed (%)		9.3	-	11.9		11.3
								Severity (%)		53.7	-	82.6		68.8
								Spreads (bps)		300	-	400		349.3
		435				Single Vendor
		1,948				Consensus		Default Rate (%)		0.1	-	10.3		3.5
								Prepayment Speed (%)		0.1	-	32.9		9.9
								Severity (%)		7.2	-	100		62.3
								Spreads (bps)		210.6	-	404.2		336.7
		740				Consensus
		420				Discounted Cash Flow		Default Rate (%)		2.3	-	10.1		5.1
								Prepayment Speed (%)		1.2	-	7		3.4
								Severity (%)		45.2	-	79.5		60.5
								Spreads (bps)		220.2	-	500		381.3
		109				Other
Total Alt-A private-label securities		3,791
Subprime private-label securities(3)		442				Single Vendor		Default Rate (%)		1.8	-	11		7.4
								Prepayment Speed (%)		1	-	9.4		2
								Severity (%)		65	-	100		82.2
								Spreads (bps)		275	-	375		315.2
		322				Single Vendor
		2,981				Consensus		Default Rate (%)		0	-	36.8		7.4
								Prepayment Speed (%)		0.3	-	9.7		2.3
								Severity (%)		36.8	-	100		81.7
								Spreads (bps)		175	-	375		319.9
		2,442				Consensus
		816				Discounted Cash Flow		Default Rate (%)		0.7	-	7.6		5.1
								Prepayment Speed (%)		0.2	-	12.5		4.1
								Severity (%)		43.8	-	98		79.5
								Spreads (bps)		175	-	375		292.4
		65				Other
Total subprime private-label securities		7,068
Mortgage revenue bonds		1,937				Single Vendor		Spreads (bps)		0	-	463.2		112.1
		1,386				Single Vendor
		1,899				Discounted Cash Flow		Spreads (bps)		5.5	-	490		310
		31				Other
Total mortgage revenue bonds		5,253
Other		122				Single Vendor
		483				Consensus		Default Rate (%)		0.1	-	5		5
								Prepayment Speed (%)		3	-	11.4		3
								Severity (%)		65	-	85		84.6
								Spreads (bps)		275	-	925		526.4
		625				Consensus
		610				Discounted Cash Flow		Default Rate (%)		5				5
								Prepayment Speed (%)		10				10
								Severity (%)		55				55
								Spreads (bps)		300	-	511		469.5
		1,045				Other
Total other		2,885
Total available-for-sale securities		$	19,012
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)						Weighted - Average(1)
		(Dollars in millions)
Mortgage loans of consolidated trusts:
Single-family		$	1,828			Build-Up		Default Rate (%)		0.1		-	95.6			15.7
								Prepayment Speed (%)		2.3		-	37.6			14.1
								Severity (%)		0		-	100			26.6
		219				Consensus
		112				Consensus		Default Rate (%)		1.1		-	4.7			3.2
								Prepayment Speed (%)		0.2		-	16.7			15.2
								Severity (%)		63.9		-	89.5			85.6
								Spreads (bps)		175		-	950			293.9
		310				Discounted Cash Flow		Default Rate (%)		1.2		-	15.7			7
								Prepayment Speed (%)		1.9		-	16.7			7
								Severity (%)		58.8		-	97.7			75.5
								Spreads (bps)		175		-	360.6			252.1
		60				Other
Total single-family		2,529
Multifamily		175				Build-Up		Spreads (bps)		62		-	243.4			114.3
Total mortgage loans of consolidated trusts		$	2,704
Net derivatives		$	(64	)		Internal Model
		32				Dealer Mark
		(8		)		Other
Total net derivatives		$	(40	)
Long-term debt:
Of Fannie Mae:
Senior floating		$	(266	)		Discounted Cash Flow
		(689		)		Consensus		Default Rate (%)		0.2						0.2
								Prepayment Speed (%)		8.4						8.4
								Spreads (bps)		171		-	438			306.2
Total of Fannie Mae		(955		)
Of consolidated trusts		(227		)		Consensus
		(116		)		Consensus		Default Rate (%)		1.1		-	4.7			3.2
								Prepayment Speed (%)		0.2		-	16.7			15.2
								Severity (%)		63.9		-	89.5			85.6
								Spreads (bps)		175		-	950			295.1
		(80		)		Single Vendor
		(95		)		Other
Total of consolidated trusts		(518		)
Total long-term debt		$	(1,473	)
_________
(1)	Valuation techniques for which no unobservable inputs are disclosed generally reflect the use of third-party pricing services or dealers, and the range of unobservable inputs applied by these sources is not readily available or cannot be reasonably estimated. Where we have disclosed unobservable inputs for consensus and single vendor techniques, those inputs are based on our validations performed at the security level using discounted cash flows.
(2)	Includes Fannie Mae and Freddie Mac securities.
(3)	Default Rate as disclosed represents the estimated beginning annualized rate of default and is used as a basis to forecast the future default rates that serve as an input for valuation.
The following table displays valuation techniques for our Level 3 assets measured at fair value on a nonrecurring basis as of June 30, 2014 and December 31, 2013. The significant unobservable inputs related to these techniques primarily relate to collateral dependent valuations. The related ranges and weighted averages are not meaningful when aggregated as they vary significantly from property to property.
			Fair Value Measurements as of
	Valuation Techniques		30-Jun-14						31-Dec-13
				(Dollars in millions)
Nonrecurring fair value measurements:
Mortgage loans held for sale, at lower of cost or fair value	Consensus			$	112					$	132
	Build-Up			39						—
Total mortgage loans held for sale, at lower of cost or fair value				151						132
Single-family mortgage loans held for investment, at amortized cost:
Of Fannie Mae	Internal Model			17,189						19,966
Of consolidated trusts	Internal Model			53						79
Multifamily mortgage loans held for investment, at amortized cost	Appraisals			44						39
	Broker Price Opinions			109						248
	Asset Manager Estimate			842						1,230
	Other			38						16
Total multifamily mortgage loans held for investment, at amortized cost				1,033						1,533
Acquired property, net:
Single-family	Accepted Offers			854						691
	Appraisals			1,370						1,077
	Walk Forwards			1,174						1,106
	Internal Model			783						1,049
	Other			119						118
Total single-family				4,300						4,041
Multifamily	Accepted Offers			17						24
	Appraisals			68						65
	Broker Price Opinions			78						9
Total multifamily				163						98
Other assets	Appraisals			1						26
	Internal Model			104						81
	Other			8						14
Total other assets				113						121
Total nonrecurring assets at fair value				$	23,002					$	25,970
We use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. The following is a description of the valuation techniques we use for fair value measurement and disclosure as well as our basis for classifying these measurements as Level 1, Level 2 or Level 3 of the valuation hierarchy in more specific situations.
Trading Securities and Available-for-Sale Securities
These securities are recorded in our condensed consolidated balance sheets at fair value on a recurring basis. Fair value is measured using quoted market prices in active markets for identical assets, when available.
We classify securities whose values are based on quoted market prices in active markets for identical assets as Level 1 of the valuation hierarchy. We classify securities in active markets as Level 2 of the valuation hierarchy if quoted market prices in active markets for identical assets are not available. For all valuation techniques used for securities where there is limited activity or less transparency around these inputs to the valuation, these securities are classified as Level 3 of the valuation hierarchy.
A description of our securities valuation techniques is as follows:
Single Vendor: This valuation technique utilizes one vendor price to estimate fair value. We generally validate these observations of fair value through the use of a discounted cash flow technique whose unobservable inputs (for example, default rates) are disclosed in the table above.
Consensus: This technique utilizes an average of two or more vendor prices for similar securities. We generally validate these observations of fair value through the use of a discounted cash flow technique whose unobservable inputs (for example, default rates) are disclosed in the table above.
Discounted Cash Flow: In the absence of prices provided by third-party pricing services supported by observable market data, we estimate the fair value of a portion of our securities using a discounted cash flow technique that uses inputs such as default rates, prepayment speeds, loss severity and spreads based on market assumptions where available.
For private-label securities, an increase in unobservable prepayment speeds in isolation would generally result in an increase in fair value, and an increase in unobservable spreads, severity rates or default rates in isolation would generally result in a decrease in fair value. For mortgage revenue bonds classified as Level 3 of the valuation hierarchy, an increase in unobservable spreads would result in a decrease in fair value. Although the sensitivities of the fair value of our recurring Level 3 securities of the valuation hierarchy to various unobservable inputs are discussed above in isolation, interrelationships exist among these inputs such that a change in one unobservable input typically results in a change to one or more of the other inputs.
Mortgage Loans Held for Investment
The majority of HFI loans are reported in our condensed consolidated balance sheets at the principal amount outstanding, net of cost basis adjustments and an allowance for loan losses. We estimate the fair value of HFI loans using the build-up and consensus valuation techniques, as discussed below, for periodic disclosure of financial instruments as required by GAAP. For our remaining loans, which include those containing embedded derivatives that would otherwise require bifurcation and consolidated loans of senior-subordinated trust structures, we elected the fair value option and therefore, we record these loans at fair value in our condensed consolidated balance sheets. We measure these loans on a recurring basis using the build-up, consensus, discounted cash flow and single vendor price techniques. Certain impaired loans are measured at fair value on a nonrecurring basis by using the fair value of their underlying collateral. Specific techniques used include internal models, broker price opinions and appraisals.
A description of our loan valuation techniques is as follows:
Build-up: We derive the fair value of mortgage loans using a build-up valuation technique. In the build-up valuation technique we start with the base value for our Fannie Mae MBS and then add or subtract the fair value of the associated guaranty asset, guaranty obligation (“GO”) and master servicing arrangement. We use observable market values of Fannie Mae MBS with similar characteristics, either on a pool or loan level, determined primarily from third party pricing services, quoted market prices in active markets for similar securities, and other observable market data as a base value. We set the GO equal to the estimated fair value we would receive if we were to issue our guaranty to an unrelated party in a stand-alone arm’s length transaction at the measurement date. We estimate the fair value of the GO using our internal valuation models, which calculate the present value of expected cash flows based on management’s best estimate of certain key assumptions such as current mark-to-market LTV ratios, future house prices, default rates, severity rates and required rate of return. We also estimate the fair value of the GO using our current guaranty pricing and adjust that pricing, as appropriate, for the seasoning of the collateral when such transactions reflect credit characteristics of loans held in our portfolio. As a result, the fair value of our mortgage loans will change when the pricing for our credit guaranty changes in the GSE securitization market.
Our performing loans are generally classified as Level 2 of the valuation hierarchy to the extent that significant inputs are observable. To the extent that unobservable inputs are significant, the loans are classified as Level 3 of the valuation hierarchy.
Consensus: The fair value of single-family nonperforming loans represents an estimate of the prices we would receive if we were to sell these loans in the whole-loan market. These nonperforming loans are either two or more months delinquent, in an open modification period, or in a closed modification state (both performing and nonperforming in accordance with the loan’s modified terms). We calculate the fair value of nonperforming loans based on certain key factors, including collateral value, cash flow characteristics and mortgage insurance repayment. Collateral value is derived from the current estimated mark-to-market LTV ratio of the individual loan and, where appropriate, a state-level distressed property sales discount. Cash flow characteristics include attributes such as the weighted average coupon rate and loan payment history. The fair value of mortgage insurance is estimated by taking the loan level coverage and adjusting it by the expected claims paying ability of the associated mortgage insurer. The expected claims paying abilities used for estimating the fair value of mortgage insurance are consistent with our credit loss forecast. Fair value is estimated from the extrapolation of indicative sample bids obtained from multiple active market participants plus the estimated value of any applicable mortgage insurance. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
We estimate the fair value for a portion of our senior-subordinated trust structures using the average of two or more vendor prices at the security level as a proxy for estimating loan fair value. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Discounted Cash Flow: We estimate the fair value of a portion of our senior-subordinated trust structures using discounted cash flow at the security level as a proxy for estimating loan fair value. This valuation technique uses unobservable inputs such as prepayment speeds, default rates, spreads, and loss severities to estimate the fair value of our securities. These inputs are weighted in a model that calculates the expected cash flow of the security which is used as the basis of fair value. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Single Vendor: We estimate the fair value of a portion of our senior-subordinated trust structures using the single vendor valuation technique at the security level as a proxy for estimating loan fair value. We also estimate the fair value of our reverse mortgages using the single vendor valuation technique. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Internal Model: For loans whose value it has been determined should be based on collateral value, we use an internal proprietary distressed home price model. The internal model used in this process takes one of two approaches when valuing the collateral.
The first approach relies on comparable foreclosed property sales to estimate the value of the target collateral. The comparable foreclosed property sales approach uses various factors such as geographic distance, transaction time and the value difference. The second approach referred to as the median Metropolitan Statistical Area (“MSA”) is based on the median of all the foreclosure sales of REOs in a specific MSA. Using this sales price, MSA level discount is computed and applied to the estimated non distressed value to derive an estimated fair value. If there are not enough REO sales in a specific MSA, a median state level foreclosure discount is used to estimate the fair value.
The majority of the internal model valuations come from the comparable sales approach. The determination of whether the internal model valuations in a particular geographic area should use the comparable sales approach or median MSA is based on historical accuracy. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Appraisals: For a portion of our multifamily loans, we use appraisals to estimate the fair value of the loan. There are three approaches used to estimate fair value of a specific property: (1) cost, (2) income capitalization and (3) sales comparison. The cost approach uses the insurable value as a basis. The unobservable inputs used in this model include the estimated cost to construct or replace multifamily properties in the closest localities available. The income capitalization approach estimates the fair value using the present value of the future cash flow expectations by applying an appropriate overall capitalization rate to the forecasted net operating income. The significant unobservable inputs used in this calculation include rental income, fees associated with rental income, expenses associated with the property including taxes, payroll, insurance and other items, and capitalization rates, which are determined through market extraction and the debt service coverage ratio. The sales comparison approach compares the prices paid for similar properties, the prices asked by owners and offers made. The unobservable inputs to this methodology include ratios of sales prices to annual gross income, price paid per unit and adjustments made based on financing, conditions of sale and physical characteristics of the property. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Broker Price Opinion (“BPO”): For a portion of our multifamily loans, we use BPO to estimate the fair value of the loan. This technique uses both current property value and the property value adjusted for stabilization and market conditions. These approaches compute net operating income based on current rents and expenses and use a range of market capitalization rates to estimate property value. The unobservable inputs used in this technique are property net operating income and market capitalization rates to estimate property value. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
Asset Manager Estimate (“AME”): For a portion of our multifamily loans, AME is used to estimate the fair value of the loan. This technique uses the net operating income and tax assessments of the specific property as well as MSA-specific market capitalization rates and average per unit sales values to estimate property fair value. These loans are classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
An increase in prepayment speeds in isolation would generally result in an increase in the fair value of our mortgage loans classified as Level 3 of the valuation hierarchy, and an increase in severity rates, default rates or spreads in isolation would generally result in a decrease in fair value. Although the sensitivities of the fair value of mortgage loans classified as Level 3 of the valuation hierarchy to various unobservable inputs are discussed above in isolation, interrelationships exist among these inputs such that a change in one unobservable input typically results in a change to one or more of the other inputs.
Acquired Property, Net and Other Assets
Acquired property, net represents foreclosed property received in full satisfaction of a loan net of a valuation allowance. Acquired property is initially recorded in our condensed consolidated balance sheets at its fair value less its estimated cost to sell. The initial fair value of foreclosed properties is determined using a hierarchy based on the reliability of available information. The hierarchy for single-family acquired property includes accepted offers, appraisals, broker price opinions and proprietary home price model values. The hierarchy for multifamily acquired property includes accepted offers, appraisals and broker price opinions. We consider an accepted offer on a specific foreclosed property to be the best estimate of its fair value. If we have not accepted an offer on the property we use the next highest priority valuation methodology available, as described in our valuation hierarchy to determine fair value. While accepted offers represent an agreement in principle to transact, a significant portion of these agreements do not get executed for various reasons, and are therefore classified as Level 3 of the valuation hierarchy.
Third-party valuations can be obtained from either an appraisal or a broker price opinion. These valuations are kept current using a monthly walk forward process that updates them for any change in the value of the property. When accepted offers or third-party valuations are not available, we generally utilize the home price values determined using an internal model.
Subsequent to initial measurement, the foreclosed properties that we intend to sell are reported at the lower of the carrying amount or fair value less estimated costs to sell. Foreclosed properties classified as held for use, included in “Other Assets” in our condensed consolidated balance sheets, are depreciated and impaired when circumstances indicate that the carrying amount of the property is no longer recoverable. The fair values of our single-family foreclosed properties subsequent to initial measurement are determined using the same information hierarchy used for the initial fair value measurement.
The most commonly used techniques in our valuation of acquired property are proprietary home price model and appraisals (both current and walk forward). Based on the number of properties measured as of June 30, 2014, these methodologies comprised approximately 76% of our valuations, while accepted offers comprised approximately 20% of our valuations. Based on the number of properties measured as of December 31, 2013, these methodologies comprised approximately 81% of our valuations, while accepted offers comprised approximately 16% of our valuations.
Acquired property is classified as Level 3 of the valuation hierarchy because significant inputs are unobservable.
A description of our acquired property significant valuation techniques is as follows:
Single-family acquired property valuation techniques
Appraisal: An appraisal is an estimate of the value of a specific property by a certified or licensed appraiser, in accordance with the Uniform Standards of Professional Appraisal Practice. Data most commonly used is from the local Multiple Listing Service and includes properties currently listed for sale, properties under contract, and closed transactions. The appraiser performs an analysis that starts with these data points and then adjusts for differences between the comparable properties and the property being appraised, to arrive at an estimated value for the specific property. Adjustments are made for differences between comparable properties for unobservable inputs such as square footage, location, and condition of the property. The appraiser typically uses recent historical data for the estimate of value.
Broker Price Opinion: This technique provides an estimate of what the property is worth based upon a real estate broker’s knowledge. The broker uses research of pertinent data in the appropriate market, and a sales comparison approach that is similar to the appraisal process. The broker typically has insight into local market trends, such as the number of and terms of offers, lack of offers, increasing supply, shortage of inventory and overall interest in buying a home. This information, all of which is unobservable, is used along with recent and pending sales and current listings of similar properties to arrive at an estimate of value.
We review the appraisals and broker price opinions received to determine if they have been performed in accordance with applicable standards and if the results are consistent with our observed transactions on similar properties. We make necessary adjustments as required.
Appraisal and Broker Price Opinion Walk Forwards (“Walk Forwards”): We use these techniques to adjust appraisal and broker price opinion valuations for changing market conditions by applying a walk forward factor based on local price movements since the time the third-party value was obtained. The majority of third-party values are updated by comparing the difference in our internal home price model from the month of the original appraisal/broker price opinion to the current period and by applying the resulting percentage change to the original value. If a price is not determinable through our internal home price model, we use our zip code level home price index to update the valuations.
Internal Model: We use an internal model to estimate fair value for distressed properties. The valuation methodology and inputs used are described under “Mortgage Loans Held for Investment.”
Multifamily acquired property valuation techniques
Appraisals: We use this method to estimate property values for distressed properties. The valuation methodology and inputs used are described under “Mortgage Loans Held for Investment.”
Broker Price Opinions: We use this method to estimate property values for distressed properties. The valuation methodology and inputs used are described under “Mortgage Loans Held for Investment.”
Derivatives Assets and Liabilities (collectively “Derivatives”)
Derivatives are recorded in our condensed consolidated balance sheets at fair value on a recurring basis. The valuation process for the majority of our risk management derivatives uses observable market data provided by third-party sources, resulting in Level 2 classification of the valuation hierarchy.
A description of our derivatives valuation techniques is as follows:
Internal Model: We use internal models to value interest rate swaps which are valued by referencing yield curves derived from observable interest rates and spreads to project and discount swap cash flows to present value. Option-based derivatives use an internal model that projects the probability of various levels of interest rates by referencing swaption volatilities provided by market makers/dealers. The projected cash flows of the underlying swaps of these option-based derivatives are discounted to present value using yield curves derived from observable interest rates and spreads.
Dealer Mark: Certain highly complex structured swaps primarily use a single dealer mark due to lack of transparency in the market and may be modeled using observable interest rates and volatility levels as well as significant unobservable assumptions, resulting in Level 3 classification of the valuation hierarchy. Mortgage commitment derivatives that use observable market data, quotes and actual transaction price levels adjusted for market movement are typically classified as Level 2 of the valuation hierarchy. To the extent mortgage commitment derivatives include adjustments for market movement that cannot be corroborated by observable market data, we classify them as Level 3 of the valuation hierarchy.
Debt
The majority of debt of Fannie Mae is recorded in our condensed consolidated balance sheets at the principal amount outstanding, net of cost basis adjustments. We elected the fair value option for certain structured Fannie Mae debt instruments and debt of consolidated trusts with embedded derivatives, which are recorded in our condensed consolidated balance sheets at fair value on a recurring basis.
We classify debt instruments that have quoted market prices in active markets for similar liabilities when traded as assets as Level 2 of the valuation hierarchy. For all valuation techniques used for debts instruments where there is limited activity or less transparency around these inputs to the valuation, these debt instruments are classified as Level 3 of the valuation hierarchy.
A description of our debt valuation techniques is as follows:
Consensus: We estimate the fair value of debt of Fannie Mae and our debt of consolidated trusts using an average of two or more vendor prices or dealer marks that represents estimated fair value for similar liabilities when traded as assets.
Single Vendor: We estimate the fair value of debt of Fannie Mae and our debt of consolidated trusts using a single vendor price that represents estimated fair value for these liabilities when traded as assets.
Discounted Cash Flow: In the absence of prices provided by third-party pricing services supported by observable market data, we estimate the fair value of a portion of the debt of Fannie Mae and our debt of consolidated trusts using a discounted cash flow technique that uses spreads based on market assumptions where available.
The valuation methodology and inputs used in estimating the fair value of MBS assets are described under “Trading Securities and Available-for-Sale Securities.”
Valuation Control Processes
We have control processes that are designed to ensure that our fair value measurements are appropriate and reliable, that they are based on observable inputs wherever possible and that our valuation approaches are consistently applied and the assumptions used are reasonable. Our control processes consist of a framework that provides for a segregation of duties and oversight of our fair value methodologies and valuations, as well as validation procedures.
Our Enterprise Models Group develops models that are used in estimating the fair value of assets and liabilities for financial reporting purposes. In addition, our Model Oversight Committee (“MOC”) facilitates the cross-functional coordination and effectiveness of our modeling efforts in terms of research, model use and risk governance. The MOC comprises senior representatives from Underwriting and Pricing, Capital Markets, Multifamily, Credit Portfolio Management, Enterprise Risk Management and Finance and is co-chaired by our Chief Risk Officer and our Head of Enterprise Business Analytics. Our Model Risk Management Group is responsible for establishing risk management controls and for reviewing models used in the determination of fair value measurements for financial reporting.
The Pricing and Verification Group is responsible for the estimation and verification of the fair value for the majority of our financial assets and financial liabilities including review of material assumptions used when market-based inputs do not exist. The Pricing and Verification Group also provides a quarterly update to the Valuation Oversight Committee (“VOC”) on relevant market information, pricing trends, significant valuation challenges and the resolution of those challenges. The Pricing and Verification Group resides within our Finance Division and is independent of any trading or market related activities. Fair value measurements for acquired property and collateral dependent loans are determined by other valuation groups in the Finance Division.
Our VOC includes senior representation from our Capital Markets segment, our Enterprise Risk Office and our Finance division, and is responsible for providing overall governance for our valuation processes and results. The composition of the VOC is determined by the VOC chair, our Chief Financial Officer, with the objective of obtaining appropriate representation from Finance, Enterprise Risk Management and select business units within Fannie Mae. Based on its review of valuation methodologies and fair value results for various financial instruments used for financial reporting, the VOC is responsible for advising the VOC chair, who has the ultimate responsibility over all valuation processes and results. The VOC also reviews trend analysis for various financial assets and liabilities on a quarterly basis.
We use third-party vendor prices and dealer quotes to estimate fair value of some of our financial assets and liabilities. Third-party vendor prices are primarily used to estimate fair value for trading securities, available-for-sale securities, debt of Fannie Mae and consolidated MBS debt. Our Pricing and Verification Group performs various review and validation procedures prior to utilizing these prices in our fair value estimation process. We verify selected prices, using a variety of methods, including corroborating the prices by reference to other independent market data, such as non-binding broker or dealer quotations, relevant benchmark indices and prices of similar instruments. We also review prices for reasonableness based on variations from prices provided in previous periods, comparing prices to internally estimated prices, using primarily a discounted cash flow approach, and conducting relative value comparisons based on specific characteristics of securities.
We have discussions with the pricing vendors as part of our due diligence process in order to maintain a current understanding of the valuation processes and related assumptions and inputs that these vendors use in developing prices. The prices provided to us by third-party pricing services reflect the existence of market reliance upon credit enhancements, if any, and the current lack of liquidity in the marketplace. If we determine that a price provided to us is outside established parameters, we will further examine the price, including having follow-up discussions with the pricing service or dealer. If we conclude that a price is not valid, we will adjust the price for various factors, such as liquidity, bid-ask spreads and credit considerations. All of these procedures are executed before we use the prices in preparing our financial statements.
We have an internal property valuation function that utilizes an internal model to compare the values received on a property and assign a risk rating based on several factors including the deviation between the various values. Property valuations with risk ratings above a specified threshold are reviewed for reasonableness by a team of property valuation experts. The internal model that is used to assign a risk rating and the threshold specified is subject to VOC oversight. In addition, our Quality Control Group reviews the overall work performed and inspects a portion of the properties in major markets, for which the third-party valuations are obtained, in order to assess the quality of the valuations.
We calibrate the performance of our proprietary distressed home price model using actual offers in recently observed transactions. The model’s performance is reviewed on a monthly basis by the REO valuation team and compared quarterly to specific model performance thresholds. The results of the validation are regularly reviewed with the VOC.
Our Property Valuation Review Group reviews appraisals and broker price opinions to determine the most appropriate value by comparing data within these products with current comparable properties and market data. We conduct regular performance reviews of the counterparties that provide products and services for this process. In addition, valuation results and trend analyses are reviewed regularly by management responsible for valuing and disposing of real estate.
Fair Value of Financial Instruments
The following table displays the carrying value and estimated fair value of our financial instruments as of June 30, 2014 and December 31, 2013. The fair value of financial instruments we disclose includes commitments to purchase multifamily and single-family mortgage loans, which are off-balance sheet financial instruments that we do not record in our condensed consolidated balance sheets. The fair values of these commitments are included as “Mortgage loans held for investment, net of allowance for loan losses.” The disclosure excludes certain financial instruments, such as plan obligations for pension and postretirement health care benefits, employee stock option and stock purchase plans, and also excludes all non-financial instruments. As a result, the fair value of our financial assets and liabilities does not represent the underlying fair value of our total consolidated assets and liabilities.
	As of June 30, 2014
	Carrying				Quoted Price in Active Markets for Identical Assets				Significant Other Observable Inputs				Significant Unobservable Inputs				Netting Adjustment				Estimated
	Value				(Level 1)				(Level 2)				(Level 3)								Fair Value
	(Dollars in millions)
Financial assets:
Cash and cash equivalents and restricted cash	$	50,434			$	34,884			$	15,550			$	—			$	—			$	50,434
Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700				—				16,700				—				—				16,700
Trading securities	26,630				13,083				10,878				2,669				—				26,630
Available-for-sale securities	34,026				—				17,216				16,810				—				34,026
Mortgage loans held for sale	625				—				169				492				—				661
Mortgage loans held for investment, net of allowance for loan losses:
Of Fannie Mae	247,966				—				29,361				219,051				—				248,412
Of consolidated trusts	2,756,195				—				2,620,397				191,574				—				2,811,971
Mortgage loans held for investment	3,004,161				—				2,649,758				410,625				—				3,060,383
Advances to lenders	4,741				—				4,220				505				—				4,725
Derivative assets at fair value	1,264				—				8,022				139				(6,897		)		1,264
Guaranty assets and buy-ups	253				—				—				766				—				766
Total financial assets	$	3,138,834			$	47,967			$	2,722,513			$	432,006			$	(6,897	)		$	3,195,589
Financial liabilities:
Short-term debt:
Of Fannie Mae	$	90,926			$	—			$	90,935			$	—			$	—			$	90,935
Of consolidated trusts	1,844				—				—				1,844				—				1,844
Long-term debt:
Of Fannie Mae	386,609				—				398,264				940				—				399,204
Of consolidated trusts	2,710,166				—				2,754,120				15,054				—				2,769,174
Derivative liabilities at fair value	736				—				10,007				119				(9,390		)		736
Guaranty obligations	453				—				—				2,049				—				2,049
Total financial liabilities	$	3,190,734			$	—			$	3,253,326			$	20,006			$	(9,390	)		$	3,263,942
	As of December 31, 2013
	Carrying				Quoted Price in Active Markets for Identical Assets				Significant Other Observable Inputs				Significant Unobservable Inputs				Netting Adjustment				Estimated
	Value				(Level 1)				(Level 2)				(Level 3)								Fair Value
	(Dollars in millions)
Financial assets:
Cash and cash equivalents and restricted cash	$	48,223			$	36,633			$	11,590			$	—			$	—			$	48,223
Federal funds sold and securities purchased under agreements to resell or similar arrangements	38,975				—				38,975				—				—				38,975
Trading securities	30,768				16,306				11,688				2,774				—				30,768
Available-for-sale securities	38,171				—				19,159				19,012				—				38,171
Mortgage loans held for sale	380				—				185				195				—				380
Mortgage loans held for investment, net of allowance for loan losses:
Of Fannie Mae	259,638				—				29,920				215,960				—				245,880
Of consolidated trusts	2,766,222				—				2,569,747				176,395				—				2,746,142
Mortgage loans held for investment	3,025,860				—				2,599,667				392,355				—				2,992,022
Advances to lenders	3,727				—				3,165				523				—				3,688
Derivative assets at fair value	2,073				—				10,430				65				(8,422		)		2,073
Guaranty assets and buy-ups	267				—				—				706				—				706
Total financial assets	$	3,188,444			$	52,939			$	2,694,859			$	415,630			$	(8,422	)		$	3,155,006
Financial liabilities:
Short-term debt:
Of Fannie Mae	$	72,295			$	—			$	72,304			$	—			$	—			$	72,304
Of consolidated trusts	2,154				—				—				2,154				—				2,154
Long-term debt:
Of Fannie Mae	457,139				—				463,991				1,557				—				465,548
Of consolidated trusts	2,702,935				—				2,684,224				13,362				—				2,697,586
Derivative liabilities at fair value	1,469				—				10,734				105				(9,370		)		1,469
Guaranty obligations	485				—				—				2,433				—				2,433
Total financial liabilities	$	3,236,477			$	—			$	3,231,253			$	19,611			$	(9,370	)		$	3,241,494
Financial Instruments for which fair value approximates carrying value—We hold certain financial instruments that are not carried at fair value but for which the carrying value approximates fair value due to the short-term nature and negligible credit risk inherent in them. These financial instruments include cash and cash equivalents, the majority of advances to lenders, and federal funds and securities sold/purchased under agreements to repurchase/resell.
Federal funds and securities sold/purchased under agreements to repurchase/resell—The carrying value for the majority of these specific instruments approximates the fair value due to the short-term nature and the negligible inherent credit risk, as they involve the exchange of liquid collateral. Were we to calculate the fair value of these instruments we would use observable inputs resulting in Level 2 classification.
Mortgage Loans Held for Sale—Loans are reported at the lower of cost or fair value in our condensed consolidated balance sheets. The valuation methodology and inputs used in estimating the fair value of HFS loans are the same as for our HFI loans and are described under “Fair Value Measurement—Mortgage Loans Held for Investment.” These loans are classified as Level 2 of the valuation hierarchy to the extent that significant inputs are observable. To the extent that significant inputs are unobservable, the loans are classified within Level 3 of the valuation hierarchy.
HARP Loans—We measure the fair value of loans that are delivered under the Home Affordable Refinance Program (“HARP”) using a modified build-up approach while the loan is performing. Under this modified approach, we set the credit component of the consolidated loans (that is, the guaranty obligation) equal to the compensation we would currently receive for a loan delivered to us under the program because the total compensation for these loans is equal to their current exit price in the GSE securitization market. For a description of the build-up valuation methodology, refer to “Fair Value Measurement—Mortgage Loans Held for Investment.” We will continue to use this pricing methodology as long as the HARP program is available to market participants. If, subsequent to delivery, the refinanced loan becomes past due or is modified as a part of a troubled debt restructuring, the fair value of the guaranty obligation is then measured consistent with other loans that have similar characteristics.
The total compensation that we receive for the delivery of a HARP loan reflects the pricing that we are willing to offer because HARP is a part of a broader government program intended to provide assistance to homeowners and prevent foreclosures. If these benefits were not reflected in the pricing for these loans (that is, if the loans were valued using our standard build-up approach), the fair value disclosed in the table above would be lower by $10.1 billion as of June 30, 2014 and $11.5 billion as of December 31, 2013. The total fair value of our mortgage loans that have been refinanced under HARP as presented in the table above is $303.6 billion as of June 30, 2014 and $306.9 billion as of December 31, 2013.
Advances to Lenders—The carrying value for the majority of our advances to lenders approximates fair value due to the short-term nature and the negligible inherent credit risk. If we were to calculate the fair value of these instruments we would use discounted cash flow models that use observable inputs such as spreads based on market assumptions, resulting in Level 2 classification.
Advances to lenders also include loans for which the carrying value does not approximate fair value. These loans do not qualify for Fannie Mae MBS securitization and are valued using market-based techniques including credit spreads, severities and prepayment speeds for similar loans, through third-party pricing services or through a model approach incorporating both interest rate and credit risk simulating a loan sale via a synthetic structure. We classify these valuations as Level 3 given that significant inputs are not observable or are determined by extrapolation of observable inputs.
Guaranty Assets and Buy-ups—Guaranty assets related to our portfolio securitizations are recorded in our condensed consolidated balance sheets at fair value on a recurring basis and are classified as Level 3. Guaranty assets in lender swap transactions are recorded in our condensed consolidated balance sheets at the lower of cost or fair value. These assets, which are measured at fair value on a nonrecurring basis, are also classified as Level 3.
We estimate the fair value of guaranty assets based on the present value of expected future cash flows of the underlying mortgage assets using management’s best estimate of certain key assumptions, which include prepayment speeds, forward yield curves, and discount rates commensurate with the risks involved. These cash flows are projected using proprietary prepayment, interest rate and credit risk models. Because guaranty assets are like an interest-only income stream, the projected cash flows from our guaranty assets are discounted using one-month LIBOR plus an option-adjusted spread that is calibrated using a representative sample of interest-only swaps that reference Fannie Mae MBS. We believe the remitted fee income is less liquid than interest-only swaps and more like an excess servicing strip. Therefore, we take a further discount of the present value for these liquidity considerations. This discount is based on market quotes from third-party pricing services.
The fair value of the guaranty assets includes the fair value of any associated buy-ups, which is estimated in the same manner as guaranty assets but is recorded separately as a component of “Other assets” in our condensed consolidated balance sheets.
Guaranty Obligations—The fair value of all guaranty obligations, measured subsequent to their initial recognition, is our estimate of a hypothetical transaction price we would receive if we were to issue our guaranty to an unrelated party in a standalone arm’s-length transaction at the measurement date. These obligations are classified as Level 3. The valuation methodology and inputs used in estimating the fair value of the guaranty obligations are described under “Fair Value Measurement—Mortgage Loans Held for Investment, Build-up.”
Fair Value Option
We elected the fair value option for our credit risk sharing debt securities issued under our Connecticut Avenue Securities series and certain loans of consolidated trusts that contain embedded derivatives that would otherwise require bifurcation. Under the fair value option, we elected to carry these instruments at fair value instead of bifurcating the embedded derivative from the respective loan.
We elected the fair value option for all long-term structured debt instruments that are issued in response to specific investor demand and have interest rates that are based on a calculated index or formula and are economically hedged with derivatives at the time of issuance. By electing the fair value option for these instruments, we are able to eliminate the volatility in our results of operations that would otherwise result from the accounting asymmetry created by recording these structured debt instruments at cost while recording the related derivatives at fair value.
We elected the fair value option for the financial assets and liabilities of the consolidated senior-subordinate trust structures. By electing the fair value option for these instruments, we are able to eliminate the volatility in our results of operations that would otherwise result from different accounting treatment between loans at cost and debt at cost.
Interest income for the mortgage loans is recorded in “Interest income- Mortgage Loans” and interest expense for the debt instruments is recorded in “Interest expense- Long-term debt” in our condensed consolidated statements of operations and comprehensive income.
The following table displays the fair value and unpaid principal balance of the financial instruments for which we have made fair value elections as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014																		31-Dec-13
	Loans of Consolidated Trusts(1)						Long-Term Debt of Fannie Mae						Long-Term Debt of Consolidated Trusts(2)						Loans of Consolidated Trusts(1)						Long-Term Debt of Fannie Mae						Long-Term Debt of Consolidated Trusts(2)
		(Dollars in millions)
Fair value		$	15,116					$	3,432					$	16,420					$	14,268					$	1,308					$	14,976
Unpaid principal balance		14,732						3,239						15,086						14,440						1,290						13,988
__________
(1)	Includes nonaccrual loans with a fair value of $204 million and $196 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these nonaccrual loans as of June 30, 2014 and December 31, 2013 was $67 million and $74 million, respectively. Includes loans that are 90 days or more past due with a fair value of $276 million and $288 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these 90 or more days past due loans as of June 30, 2014 and December 31, 2013 was $64 million and $75 million, respectively.
(2)	Includes interest-only debt instruments with no unpaid principal balance and a fair value of $74 million and $85 million as of June 30, 2014 and December 31, 2013, respectively.
Changes in Fair Value under the Fair Value Option Election
The following table displays fair value gains and losses, net, including changes attributable to instrument-specific credit risk, for loans and debt for which the fair value election was made. Amounts are recorded as a component of “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013.
	For the Three Months Ended June 30,
	2014																2013
	Loans				Long-Term Debt						Total (Losses) Gains						Loans				Long-Term Debt						Total Gains (Losses)
	(Dollars in millions)
Changes in instrument-specific credit risk	$	16				$	(76	)				$	(60	)			$	66				$	2					$	68
Other changes in fair value	371					(221		)				150					(549		)			339						(210		)
Fair value (losses) gains, net	$	387				$	(297	)				$	90				$	(483	)			$	341					$	(142	)
	For the Six Months Ended June 30,
	2014																2013
	Loans				Long-Term Debt						Total (Losses) Gains						Loans				Long-Term Debt						Total Losses
	(Dollars in millions)
Changes in instrument-specific credit risk	$	25				$	(127	)				$	(102	)			$	1				$	(3	)				$	(2	)
Other changes in fair value	494					(337		)				157					(706		)			405						(301		)
Fair value (losses) gains, net	$	519				$	(464	)				$	55				$	(705	)			$	402					$	(303	)
In determining the changes in the instrument-specific credit risk for loans, the changes in the associated credit-related components of these loans, primarily the guaranty obligation, were taken into consideration with the overall change in the fair value of the loans for which we elected the fair value option for financial instruments. In determining the changes in the instrument-specific credit risk for debt, the changes in Fannie Mae debt spreads to LIBOR that occurred during the period were taken into consideration with the overall change in the fair value of the debt for which we elected the fair value option for financial instruments. Specifically, cash flows are evaluated taking into consideration any derivatives through which Fannie Mae has swapped out of the structured features of the notes and thus created a floating-rate LIBOR-based debt instrument. The change in value of these LIBOR-based cash flows based on the Fannie Mae yield curve at the beginning and end of the period represents the instrument-specific risk.

Commitments_and_Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	We are party to various types of legal actions and proceedings, including actions brought on behalf of various classes of claimants. We also are subject to regulatory examinations, inquiries and investigations and other information gathering requests. In some of the matters, indeterminate amounts are sought. Modern pleading practice in the U.S. permits considerable variation in the assertion of monetary damages or other relief. Jurisdictions may permit claimants not to specify the monetary damages sought or may permit claimants to state only that the amount sought is sufficient to invoke the jurisdiction of the trial court. This variability in pleadings, together with our and our counsel’s actual experience in litigating or settling claims, leads us to conclude that the monetary relief that may be sought by plaintiffs bears little relevance to the merits or disposition value of claims.
	On a quarterly basis, we review relevant information about all pending legal actions and proceedings for the purpose of evaluating and revising our contingencies, reserves and disclosures.
	We have substantial and valid defenses to the claims in the proceedings described below and, where we are a party, intend to defend these matters vigorously. However, legal actions and proceedings of all types are subject to many uncertain factors that generally cannot be predicted with assurance. Accordingly, the outcome of any given matter and the amount or range of potential loss at particular points in time is frequently difficult to ascertain. Uncertainties can include how fact finders will evaluate documentary evidence and the credibility and effectiveness of witness testimony, and how courts will apply the law. Disposition valuations are also subject to the uncertainty of how opposing parties and their counsel may view the evidence and applicable law. Further, FHFA adopted a regulation in 2011, which provides, in part, that while we are in conservatorship, FHFA will not pay claims by our current or former shareholders, unless the Director of FHFA determines it is in the interest of the conservatorship. The presence of this regulation and FHFA’s assertion that FHFA will not pay claims asserted in certain cases discussed below while we are in conservatorship creates additional uncertainty in those cases.
	We establish a reserve for matters when a loss is probable and we can reasonably estimate the amount of such loss. For legal actions or proceedings where there is only a reasonable possibility that a loss may be incurred, or where we are not currently able to estimate the reasonably possible loss or range of loss, we do not establish a reserve. We are often unable to estimate the possible losses or ranges of losses, particularly for proceedings that are in their early stages of development, where plaintiffs seek indeterminate or unspecified damages, where there may be novel or unsettled legal questions relevant to the proceedings, or where settlement negotiations have not occurred or progressed.
	Given the uncertainties involved in any action or proceeding, regardless of whether we have established a reserve, the ultimate resolution of certain of these matters may be material to our operating results for a particular period, depending on, among other factors, the size of the loss or liability imposed and the level of our net income or loss for that period.
	In addition to the matters specifically described below, we are involved in a number of legal and regulatory proceedings that arise in the ordinary course of business that we do not expect will have a material impact on our business or financial condition. We have also advanced fees and expenses of certain current and former officers and directors in connection with various legal proceedings pursuant to our bylaws and indemnification agreements.
	In re Fannie Mae Securities Litigation
	Fannie Mae was a defendant in a consolidated class action lawsuit initially filed in 2004 that was pending in the U.S. District Court for the District of Columbia. In the consolidated complaint filed in 2005, lead plaintiffs Ohio Public Employees Retirement System and State Teachers Retirement System of Ohio alleged that we and certain former officers, as well as our former outside auditor, made materially false and misleading statements in violation of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, and SEC Rule 10b-5 promulgated thereunder. Plaintiffs contended that Fannie Mae’s accounting statements were inconsistent with GAAP requirements relating to hedge accounting and the amortization of premiums and discounts, and sought unspecified compensatory damages, attorneys’ fees, and other fees and costs. On January 7, 2008, the court defined the class as all purchasers of Fannie Mae common stock and call options and all sellers of publicly traded Fannie Mae put options during the period from April 17, 2001 through December 22, 2004. On October 17, 2008, FHFA, as conservator for Fannie Mae, intervened in this case. In September and December 2010, plaintiffs served expert reports claiming damages to plaintiffs under various scenarios ranging cumulatively from $2.2 billion to $8.6 billion. In 2011, the parties filed various motions for summary judgment. On September 20, 2012, the court granted summary judgment to defendant Franklin D. Raines, Fannie Mae’s former Chief Executive Officer, on all claims against him. On October 16, 2012, the court granted summary judgment to defendant J. Timothy Howard, Fannie Mae’s former Chief Financial Officer, on all claims against him. On November 20, 2012, the court granted summary judgment to defendant Leanne Spencer, Fannie Mae’s former Controller, on all claims against her.
	On April 10, 2013, the parties reached an agreement in principle to settle this litigation, subject to court approval. On May 7, 2013, the parties filed a stipulation of settlement with the court. On June 7, 2013, the court granted preliminary approval of the settlement, approved the form and manner of notice to the class, stayed non-settlement related proceedings, and set certain other deadlines related to the settlement. On October 31, 2013, the court held a hearing to evaluate the fairness of the settlement to the class, and on December 5, 2013, granted final approval of the settlement, dismissed the case with prejudice, and entered an order and judgment effecting the settlement. Fannie Mae’s contribution to the settlement did not have a material impact on our results of operations or financial condition. On January 9, 2014, Rinis Travel Service, Inc. Profit Sharing Trust U.A. 61-1989, a purported class member, appealed the court’s approval order with the U.S. Court of Appeals for the District of Columbia, but voluntarily dismissed the appeal with prejudice on March 13, 2014. On January 29, 2014, an individual purported class member also appealed the settlement approval, and plaintiffs-appellees moved to dismiss this appeal on February 6, 2014. The motion to dismiss the appeal was granted on May 8, 2014. On June 9, 2014, the individual filed a petition for rehearing en banc. That petition was denied on June 25, 2014.
	2008 Class Action Lawsuits and Related Proceedings
	Fannie Mae is a defendant in two consolidated class actions filed in 2008 and currently pending in the U.S. District Court for the Southern District of New York—In re Fannie Mae 2008 Securities Litigation and In re 2008 Fannie Mae ERISA Litigation. On February 11, 2009, the Judicial Panel on Multidistrict Litigation ordered that the cases be coordinated for pretrial proceedings. In addition, two individual securities actions involving related facts and circumstances—Comprehensive Investment Services v. Mudd and Smith v. Fannie Mae—were later filed and ultimately transferred to the same court for coordination with the class actions.
	In addition to these proceedings, certain underwriters have notified us that they have been named in various other actions arising out of certain of Fannie Mae’s preferred stock offerings and may seek indemnification for any losses arising out of those actions pursuant to the terms of our underwriting agreements with them.
	In re Fannie Mae 2008 Securities Litigation
	In a consolidated amended complaint filed on June 22, 2009, lead plaintiffs Massachusetts Pension Reserves Investment Management Board and Boston Retirement Board (for common shareholders) and Tennessee Consolidated Retirement System (for preferred shareholders) allege that we, certain of our former officers, and certain of our underwriters violated Sections 12(a)(2) and 15 of the Securities Act of 1933. Lead plaintiffs also allege that we, certain of our former officers, and our outside auditor, violated Sections 10(b) (and Rule 10b-5 promulgated thereunder) and 20(a) of the Securities Exchange Act of 1934. Lead plaintiffs seek various forms of relief, including rescission, damages, interest, costs, attorneys’ and experts’ fees, and other equitable and injunctive relief. On October 13, 2009, the court entered an order allowing FHFA to intervene.
	In 2009, the court granted the defendants’ motion to dismiss the Securities Act claims as to all defendants. In 2010, the court granted in part and denied in part the defendants’ motions to dismiss the Securities Exchange Act claims. As a result of the partial denial, some of the Securities Exchange Act claims remained pending against us and certain of our former officers. Fannie Mae filed its answer to the consolidated complaint on December 31, 2010.
	Plaintiffs filed a second amended joint consolidated class action complaint on March 2, 2012, renewing the remaining claims and adding FHFA as a defendant. On August 30, 2012, the court denied defendants’ motions to dismiss the second amended complaint, allowing plaintiffs’ Securities Exchange Act claims premised on Fannie Mae’s subprime and Alt-A disclosures to proceed along with plaintiffs’ claims premised on Fannie Mae’s risk management disclosures. Fannie Mae filed its answer to the second amended complaint on October 29, 2012.
	On July 15, 2014, the parties reached an agreement in principle to settle this litigation. The proposed settlement amount did not have a material impact on our results of operations or financial condition.
	In re 2008 Fannie Mae ERISA Litigation
	In a consolidated complaint filed in 2009, plaintiffs allege that certain of our current and former officers and directors, including members of Fannie Mae’s Benefit Plans Committee and the Compensation Committee of Fannie Mae’s Board of Directors during the relevant time periods, as fiduciaries of Fannie Mae’s Employee Stock Ownership Plan (“ESOP”), breached their duties to ESOP participants and beneficiaries by investing ESOP funds in Fannie Mae common stock when it was no longer prudent to continue to do so. Plaintiffs purport to represent a class of participants and beneficiaries of the ESOP whose accounts invested in Fannie Mae common stock beginning April 17, 2007. The plaintiffs seek unspecified damages, attorneys’ fees and other fees and costs, and injunctive and other equitable relief. Plaintiffs filed an amended complaint on March 2, 2012 adding two current Board members and then-CEO Michael J. Williams as defendants. On October 22, 2012, the court granted in part and denied in part defendants’ motions to dismiss. The court dismissed with prejudice claims against seven former and current directors and officers who joined the Board of Directors or Benefit Plans Committee after Fannie Mae was placed into conservatorship. The court allowed plaintiffs’ breach of fiduciary duty and failure to monitor claims to go forward, but dismissed plaintiffs’ conflict of interest claim. On September 23, 2013, defendants filed a motion asking the court to reconsider its October 22, 2012 order in light of the U.S. Court of Appeals for the Second Circuit’s decision in Rinehart v. Akers (In re Lehman Bros. ERISA Litigation), 722 F.3d 137 (2d Cir. 2013). The court denied the motion for reconsideration on April 21, 2014.
	Given the stage of this lawsuit, the substantial and novel legal questions that remain, and our substantial defenses, we are currently unable to estimate the reasonably possible loss or range of loss arising from this litigation.
	Comprehensive Investment Services v. Mudd
	This individual securities action was originally filed on May 13, 2009, by plaintiff Comprehensive Investment Services, Inc. against certain of our former officers and directors, and certain of our underwriters in the U.S. District Court for the Southern District of Texas. On July 7, 2009, this case was transferred to the Southern District of New York for coordination with In re Fannie Mae 2008 Securities Litigation and In re 2008 Fannie Mae ERISA Litigation. Plaintiff filed an amended complaint on May 11, 2011 against us, certain of our former officers, and certain of our underwriters. The amended complaint alleges violations of Section 10(b) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder; violations of Section 20(a) of the Securities Exchange Act of 1934; and violations of the Texas Business and Commerce Code, common law fraud, and negligent misrepresentation in connection with Fannie Mae’s May 2008 $2.0 billion offering of 8.25% non-cumulative preferred Series T stock. Plaintiff seeks relief in the form of rescission, actual damages, punitive damages, interest, costs, attorneys’ and experts’ fees, and other equitable and injunctive relief. Plaintiff filed a second amended complaint on March 2, 2012. On August 30, 2012, the court denied defendants’ motions to dismiss the second amended complaint, allowing plaintiff’s Securities Exchange Act claims premised on Fannie Mae’s subprime and Alt-A disclosures and risk management disclosures to proceed. The court granted defendants’ motions to dismiss the state law claims, as well as the federal claims based on alleged violations of GAAP, and also dismissed two of our former officers from the action. Fannie Mae filed its answer to the amended complaint on October 29, 2012.
	Given the stage of this lawsuit, the substantial and novel legal questions that remain, and our substantial defenses, we are currently unable to estimate the reasonably possible loss or range of loss arising from this litigation.
	Smith v. Fannie Mae
	This individual securities action was originally filed on February 25, 2010, by plaintiff Edward Smith against Fannie Mae and certain of its former officers as well as several underwriters in the U.S. District Court for the Central District of California. On April 12, 2010, this case was transferred to the Southern District of New York for coordination with In re Fannie Mae 2008 Securities Litigation and In re 2008 Fannie Mae ERISA Litigation. Plaintiff filed an amended complaint on April 19, 2011, which alleges violations of Section 10(b) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder; violations of Section 20(a) of the Securities Exchange Act of 1934; common law fraud and negligence claims; and California state law claims for misrepresentation in connection with Fannie Mae’s December 2007 $7.0 billion offering of 7.75% fixed-to-floating rate non-cumulative preferred Series S stock. Plaintiff seeks relief in the form of rescission, actual damages (including interest), and exemplary and punitive damages. Plaintiff filed a second amended complaint, allowing plaintiff’s Securities Exchange Act claims premised on Fannie Mae’s subprime and Alt-A disclosures and risk management disclosures to proceed, but granted defendants’ motions to dismiss the state law claims. Fannie Mae filed its answer to the amended complaint on October 29, 2012.
	Given the stage of this lawsuit, the substantial and novel legal questions that remain, and our substantial defenses, we are currently unable to estimate the reasonably possible loss or range of loss arising from this litigation.
	Senior Preferred Stock Purchase Agreements Litigation
	A number of putative class action lawsuits were filed in the U.S. District Court for the District of Columbia against us, FHFA as our conservator, Treasury and Freddie Mac from July through September 2013 by shareholders of Fannie Mae and/or Freddie Mac challenging the August 2012 amendment to each company’s senior preferred stock purchase agreement with Treasury. These lawsuits were consolidated and, on December 3, 2013, plaintiffs (preferred and common shareholders of Fannie Mae and/or Freddie Mac) filed a consolidated class action complaint in the U.S. District Court for the District of Columbia against us, FHFA as our conservator, Treasury and Freddie Mac (“In re Fannie Mae/Freddie Mac Senior Preferred Stock Purchase Agreement Class Action Litigations”). The preferred shareholder plaintiffs allege that the August 2012 amendments to the terms of the senior preferred stock purchase agreements providing that Fannie Mae and Freddie Mac would pay dividends equal to their entire net worth (minus a specified capital reserve amount) (“the net worth sweep provisions”) nullified certain of the shareholders’ rights, particularly the right to receive dividends. The common shareholder plaintiffs allege that the August 2012 amendments constituted a taking of their property by requiring that all future profits of Fannie Mae and Freddie Mac are paid to Treasury. Plaintiffs allege claims for breach of contract and breach of the implied covenant of good faith and fair dealing against us, FHFA and Freddie Mac, a takings claim against FHFA and Treasury, and a breach of fiduciary duty claim derivatively on our and Freddie Mac’s behalf against FHFA and Treasury. Plaintiffs seek to represent several classes of preferred and/or common shareholders of Fannie Mae and/or Freddie Mac who held stock as of the public announcement of the August 2012 amendments. Plaintiffs seek unspecified damages, equitable and injunctive relief, and costs and expenses, including attorneys’ fees.
	A non-class action suit, Arrowood Indemnity Company v. Fannie Mae, was filed in the U.S. District Court for the District of Columbia on September 20, 2013 by preferred shareholders against us, FHFA as our conservator, the Director of FHFA (in his official capacity), Treasury, the Secretary of the Treasury (in his official capacity) and Freddie Mac. Plaintiffs bring claims for breach of contract and breach of the implied covenant of good faith and fair dealing against us, FHFA and Freddie Mac, and claims for violation of the Administrative Procedure Act against the FHFA and Treasury defendants, alleging that the net worth sweep provisions nullified certain rights of the preferred shareholders, particularly the right to receive dividends. Plaintiffs seek damages, equitable and injunctive relief, and costs and expenses, including attorneys’ fees.
	On January 17, 2014, defendants filed motions to dismiss both the class action and non-class action suits pending in the U.S. District Court for the District of Columbia, and these motions are now fully briefed.
	Given the stage of these lawsuits, the substantial and novel legal questions that remain, and our substantial defenses, we are currently unable to estimate the reasonably possible loss or range of loss arising from this litigation.
	Housing Trust Fund
	On July 9, 2013, plaintiffs Angela Samuels, Rossana Torres, Danielle Stelluto, the National Low Income Housing Coalition and the Right to the City Alliance filed a complaint against FHFA and the Director of FHFA (in his official capacity) in the U.S. District Court for the Southern District of Florida. We are not a party to this lawsuit. The complaint challenges FHFA’s decision to suspend Fannie Mae’s and Freddie Mac’s contributions to HUD’s Housing Trust Fund. The Federal Housing Finance Regulatory Reform Act of 2008 (the “2008 Reform Act”), which was enacted on July 30, 2008, requires Fannie Mae and Freddie Mac to set aside an amount equal to 4.2 basis points for each dollar of the unpaid principal balance of their total new business purchases to fund the Housing Trust Fund and the Capital Magnet Fund, with 65% of this amount allocated to the Housing Trust Fund and the remaining 35% allocated to the Capital Magnet Fund. The 2008 Reform Act authorizes the Director of FHFA to temporarily suspend these allocations in specified circumstances. In November 2008, FHFA suspended allocations for these funds and directed Fannie Mae and Freddie Mac to not set aside or allocate funds for the Housing Trust Fund and the Capital Magnet Fund until further notice.
	Plaintiffs’ complaint alleges that FHFA’s directives ordering Fannie Mae and Freddie Mac to suspend payments to the Housing Trust Fund, and FHFA’s failure to review its decision to suspend payments once Fannie Mae’s and Freddie Mac’s financial circumstances changed, violated the Administrative Procedure Act. Plaintiffs request that the court: (1) vacate and set aside FHFA’s decision to indefinitely suspend payments by Fannie Mae and Freddie Mac to the Housing Trust Fund; (2) declare that FHFA’s actions violated the Administrative Procedure Act; (3) order FHFA to instruct Fannie Mae and Freddie Mac to proceed as if FHFA’s suspension of payments to the Housing Trust Fund had never taken place; and (4) award reasonable attorneys’ fees and costs to the plaintiffs. FHFA filed a motion to dismiss the complaint on October 16, 2013. In response to the motion, plaintiffs filed an amended complaint on October 29, 2013. FHFA filed a motion to dismiss the amended complaint on December 6, 2013, and briefing was completed on January 28, 2014.
	We cannot predict the course or the outcome of this lawsuit.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Basis of Presentation [Policy Text Block]	'
	Basis of Presentation
	The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the SEC’s instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and note disclosures required by GAAP for complete consolidated financial statements. In the opinion of management, all adjustments of a normal recurring nature considered necessary for a fair presentation have been included. The accompanying condensed consolidated financial statements include our accounts as well as the accounts of other entities in which we have a controlling financial interest. All intercompany accounts and transactions have been eliminated. To conform to our current period presentation, we have reclassified certain amounts reported in our prior periods’ condensed consolidated financial statements. Results for the six months ended June 30, 2014 may not necessarily be indicative of the results for the year ending December 31, 2014. The unaudited interim condensed consolidated financial statements as of and for the six months ended June 30, 2014 should be read in conjunction with our audited consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2013 (“2013 Form 10-K”), filed with the SEC on February 21, 2014.
Use of Estimates, Policy [Policy Text Block]	'
	Use of Estimates
	Preparing condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect our reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities as of the dates of our condensed consolidated financial statements, as well as our reported amounts of revenues and expenses during the reporting periods. Management has made significant estimates in a variety of areas including, but not limited to, valuation of certain financial instruments and other assets and liabilities, recoverability of our deferred tax assets, allowance for loan losses and reserve for guaranty losses, and other-than-temporary impairment of investment securities. Actual results could be different from these estimates.
Cash and Cash Equivalents, Policy [Policy Text Block]	'
	Statement of Cash Flows
	We classify cash flows related to trading securities based on their nature and purpose. Effective January 1, 2014, all cash flows related to trading securities purchased after December 31, 2013 are classified as operating activities as we do not intend to hold these securities for investment.
New Accounting Pronouncements, Policy [Policy Text Block]	'
	Adoption of New Accounting Guidance
	In January 2014, the FASB issued guidance clarifying when a creditor is considered to have received physical possession of residential real estate property collateralized by a consumer mortgage loan in order to reduce diversity in practice for when a creditor derecognizes the loan receivable and recognizes the real estate property. The guidance also requires interim and annual disclosure of the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The new guidance is effective for us on January 1, 2015. We do not expect that the adoption of this guidance will have a material impact on our consolidated financial statements.
	In May 2014, the FASB issued their final standard on revenue from contracts with customers. The standard outlines a single model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance in an effort to remove inconsistencies in revenue recognition standards, improve comparability across entities, provide enhanced disclosures related to revenue recognition and to converge with the jointly issued International Financial Reporting Standards revenue recognition guidance. The following contracts with customers are excluded from the scope of the new standard and will continue to be accounted for under existing guidance: leases, insurance, financial instruments (e.g., receivables, investments, liabilities, debt and derivatives) and guarantees. The new guidance is effective for us on January 1, 2017. We are evaluating this guidance and have not determined the impact, if any, on our consolidated financial statements of adopting this guidance.

Consolidation_and_Transfer_of_

Consolidation and Transfer of Financial Assets (Policies)	6 Months Ended
	Jun. 30, 2014
Consolidations and Transfers of Financial Assets [Abstract]	'
Consolidations, Policy [Policy Text Block]	'
	We have interests in various entities that are considered to be variable interest entities (“VIEs”). The primary types of entities are securitization trusts guaranteed by us via lender swap and portfolio securitization transactions, mortgage and asset-backed trusts that were not created by us, as well as housing partnerships that are established to finance the acquisition, construction, development or rehabilitation of affordable multifamily and single-family housing. These interests include investments in securities issued by VIEs, such as Fannie Mae MBS created pursuant to our securitization transactions and our guaranty to the entity. We consolidate the substantial majority of our single-class securitization trusts because our role as guarantor and master servicer provides us with the power to direct matters (primarily the servicing of mortgage loans) that impact the credit risk to which we are exposed. In contrast, we do not consolidate single-class securitization trusts when other organizations have the power to direct these activities.
	We continually assess whether we are the primary beneficiary of the VIEs with which we are involved and therefore may consolidate or deconsolidate a VIE through the duration of our involvement.
	Unconsolidated VIEs
	We do not consolidate VIEs when we are not deemed to be the primary beneficiary. Our unconsolidated VIEs include securitization trusts and limited partnerships.
Transfers and Servicing of Financial Assets, Policy [Policy Text Block]	'
	Transfers of Financial Assets
	We issue Fannie Mae MBS through portfolio securitization transactions by transferring pools of mortgage loans or mortgage-related securities to one or more trusts or special purpose entities. We are considered to be the transferor when we transfer assets from our own retained mortgage portfolio in a portfolio securitization transaction.
	Qualifying Sales of Portfolio Securitizations
	We consolidate the substantial majority of our single-class MBS trusts; therefore, these portfolio securitization transactions do not qualify for sale treatment. The assets and liabilities of consolidated trusts created via portfolio securitization transactions that do not qualify as sales are reported in our condensed consolidated balance sheets.
	We recognize assets obtained and liabilities incurred in qualifying sales of portfolio securitizations at fair value.

Mortgage_Loans_Policy_Policies

Mortgage Loans Policy (Policies)	6 Months Ended
	Jun. 30, 2014
Mortgage Loans on Real Estate [Abstract]	'
Nonaccrual Loans [Policy Text Block]	'
	Nonaccrual Loans
	We discontinue accruing interest on loans when we believe collectibility of principal or interest is not reasonably assured, which for single-family loans we have determined, based on our historical experience, to be when the loan becomes two months or more past due according to its contractual terms. We generally place multifamily loans on nonaccrual status when the loan is deemed to be individually impaired, unless the loan is well secured such that collectibility of principal and accrued interest is reasonably assured.
	When a loan is placed on nonaccrual status, interest previously accrued but not collected becomes part of our recorded investment in the loan and is reviewed for impairment in connection with our allowance for loan losses process. For single-family loans, we recognize interest income for loans on nonaccrual status when cash is received. For multifamily loans on nonaccrual status, we apply any payment received on a cost recovery basis to reduce principal on the mortgage loan.
	We return a single-family loan to accrual status at the point that the borrower has made sufficient payments to reduce their delinquency below our nonaccrual threshold. For modified single-family loans, the loan is not returned to accrual status until the borrower successfully makes all required payments during the trial period (generally three to four months) and the modification is made permanent. We generally return a multifamily loan to accrual status when the borrower cures the delinquency of the loan or we otherwise determine that the loan is well secured such that collectibility is reasonably assured.
Troubled Debt Restructurings [Policy Text Block]	'
	Troubled Debt Restructurings
	A modification to the contractual terms of a loan that results in granting a concession to a borrower experiencing financial difficulties is considered a TDR. In addition to formal loan modifications, we also engage in other loss mitigation activities with troubled borrowers, which include repayment plans and forbearance arrangements, both of which represent informal agreements with the borrower that do not result in the legal modification of the loan’s contractual terms. We account for these informal restructurings as a TDR if we defer more than three missed payments. We also classify as TDRs loans to certain borrowers who have received bankruptcy relief.

Allowance_for_Loan_Losses_Poli

Allowance for Loan Losses Policy (Policies)	6 Months Ended
	Jun. 30, 2014
Allowance for Loan Losses [Abstract]	'
Allowance for Loan Losses [Policy Text Block]	'
	Our allowance for loan losses is a valuation allowance that reflects an estimate of incurred credit losses related to our recorded investment in both single-family and multifamily HFI loans. This population includes both HFI loans held by Fannie Mae and by consolidated Fannie Mae MBS trusts. When calculating our allowance for loan losses, we consider only our net recorded investment in the loan at the balance sheet date, which includes the loan’s unpaid principal balance and accrued interest recognized while the loan was on accrual status and any applicable cost basis adjustments. We record charge-offs as a reduction to the allowance for loan losses when losses are confirmed through the receipt of assets in full satisfaction of a loan, such as the underlying collateral upon foreclosure or cash upon completion of a short sale.
	We aggregate single-family HFI loans that are not individually impaired based on similar risk characteristics, for purposes of estimating incurred credit losses and establishing a collective single-family loss reserve using an econometric model that derives an overall loss reserve estimate. We base our allowance methodology on historical events and trends, such as loss severity (in event of default), default rates, and recoveries from mortgage insurance contracts and other credit enhancements. In addition, management performs a review of the observable data used in its estimate to ensure it is representative of prevailing economic conditions and other events existing as of the balance sheet date.
	Individually impaired single-family loans currently include those restructured in a TDR and acquired credit-impaired loans. When a loan has been restructured, we measure impairment using a cash flow analysis discounted at the loan’s original effective interest rate. However, if we expect to recover our recorded investment in an individually impaired loan through probable foreclosure of the underlying collateral, we measure impairment based on the fair value of the collateral, reduced by estimated disposal costs and adjusted for estimated proceeds from mortgage, flood, or hazard insurance and other credit enhancements.
	We identify multifamily loans for evaluation for impairment through a credit risk assessment process. If we determine that a multifamily loan is individually impaired, we generally measure impairment on that loan based on the fair value of the underlying collateral less estimated costs to sell the property. If we determine that an individual loan that was specifically evaluated for impairment is not individually impaired, we include the loan as part of a pool of loans with similar characteristics that are evaluated collectively for incurred losses.

Investment_in_Securities_Polic

Investment in Securities Policies (Policies)	6 Months Ended
	Jun. 30, 2014
Investments, Debt and Equity Securities [Abstract]	'
Trading Securities, Policy [Policy Text Block]	'
	Trading Securities
	Trading securities are recorded at fair value with subsequent changes in fair value recorded as “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income.
Available-for-sale Securities, Policy [Policy Text Block]	'
	Available-for-Sale Securities
	We measure available-for-sale (“AFS”) securities at fair value with unrealized gains and losses, recorded net of tax, as a component of “Other comprehensive income” and we recognize realized gains and losses from the sale of AFS securities in “Investment gains, net” in our condensed consolidated statements of operations and comprehensive income.
	Other-Than-Temporary Impairments
	We evaluate AFS securities for other-than-temporary impairment on a quarterly basis. An other-than-temporary impairment is considered to have occurred when the fair value of a debt security is below its amortized cost basis and we intend to sell or it is more likely than not that we will be required to sell the security before recovery. An other-than-temporary impairment is also considered to have occurred if we do not expect to recover the entire amortized cost basis of a debt security even if we do not intend to sell the security or it is not more likely than not we will be required to sell the security before recovery.

Acquired_Property_Net_Policies

Acquired Property Net (Policies)	6 Months Ended
	Jun. 30, 2014
Real Estate [Abstract]	'
Acquired Property Held-For-Sale Foreclosed Assets Policy [Policy Text Block]	'
	Acquired property, net consists of held-for-sale foreclosed property received in satisfaction of a loan, net of a valuation allowance for declines in the fair value of the properties after initial acquisition. We classify properties as held-for-sale when we intend to sell the property and are actively marketing it for sale.

Derivative_Policy_Policies

Derivative Policy (Policies)	6 Months Ended
	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivatives, Policy [Policy Text Block]	'
	We recognize all derivatives as either assets or liabilities in our condensed consolidated balance sheets at their fair value on a trade date basis. Fair value amounts, which are netted to the extent a legal right of offset exists and is enforceable by law at the counterparty level and are inclusive of the right or obligation associated with the cash collateral posted or received, are recorded in “Other assets” or “Other liabilities” in our condensed consolidated balance sheets. We present cash flows from derivatives as operating activities in our condensed consolidated statements of cash flows.
	We record all derivative gains and losses, including accrued interest, in “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income.

Segment_Reporting_Segment_Repo

Segment Reporting Segment Reporting Policy (Policies)	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting, Policy [Policy Text Block]	'
	Our three reportable segments are: Single-Family, Multifamily and Capital Markets. We use these three segments to generate revenue and manage business risk, and each segment is based on the type of business activities it performs. Under our segment reporting, the sum of the results for our three business segments does not equal our condensed consolidated statements of operations and comprehensive income, as we separate the activity related to our consolidated trusts from the results generated by our three segments. Our business segment financial results include directly attributable revenues and expenses. Additionally, we allocate to each of our segments: (1) capital using FHFA minimum capital requirements adjusted for over- or under-capitalization; (2) indirect administrative costs; and (3) a provision or benefit for federal income taxes. In addition, we allocate intracompany guaranty fee income as a charge from the Single-Family and Multifamily segments to Capital Markets for managing the credit risk on mortgage loans held by the Capital Markets group. We also include an eliminations/adjustments category to reconcile our business segment financial results and the activity related to our consolidated trusts to net income in our condensed consolidated statements of operations and comprehensive income.

Netting_Arrangements_Policies

Netting Arrangements (Policies)	6 Months Ended
	Jun. 30, 2014
Offsetting [Abstract]	'
Derivatives, Offsetting Policy [Policy Text Block]	'
	We determine our rights to offset the assets and liabilities presented above with the same counterparty, including collateral posted or received, based on the contractual arrangements entered into with our individual counterparties and various rules and regulations that would govern the insolvency of a derivative counterparty.
	Derivative instruments are recorded at fair value and securities purchased under agreements to resell or similar arrangements are recorded at amortized cost in our condensed consolidated balance sheets.

Fair_Value_Policies

Fair Value (Policies)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurement, Policy [Policy Text Block]	'
	Fair Value Measurement
	Fair value measurement guidance defines fair value, establishes a framework for measuring fair value and sets forth disclosures around fair value measurements. This guidance applies whenever other accounting guidance requires or permits assets or liabilities to be measured at fair value. The guidance establishes a three-level fair value hierarchy that prioritizes the inputs into the valuation techniques used to measure fair value. The fair value hierarchy gives the highest priority, Level 1, to measurements based on unadjusted quoted prices in active markets for identical assets or liabilities. The next highest priority, Level 2, is given to measurements of assets and liabilities based on limited observable inputs or observable inputs for similar assets and liabilities. The lowest priority, Level 3, is given to measurements based on unobservable inputs.
	Fair Value Option
	We elected the fair value option for our credit risk sharing debt securities issued under our Connecticut Avenue Securities series and certain loans of consolidated trusts that contain embedded derivatives that would otherwise require bifurcation. Under the fair value option, we elected to carry these instruments at fair value instead of bifurcating the embedded derivative from the respective loan.
	We elected the fair value option for all long-term structured debt instruments that are issued in response to specific investor demand and have interest rates that are based on a calculated index or formula and are economically hedged with derivatives at the time of issuance. By electing the fair value option for these instruments, we are able to eliminate the volatility in our results of operations that would otherwise result from the accounting asymmetry created by recording these structured debt instruments at cost while recording the related derivatives at fair value.
	We elected the fair value option for the financial assets and liabilities of the consolidated senior-subordinate trust structures. By electing the fair value option for these instruments, we are able to eliminate the volatility in our results of operations that would otherwise result from different accounting treatment between loans at cost and debt at cost.
	Interest income for the mortgage loans is recorded in “Interest income- Mortgage Loans” and interest expense for the debt instruments is recorded in “Interest expense- Long-term debt” in our condensed consolidated statements of operations and comprehensive income.

Commitments_and_Contingencies_

Commitments and Contingencies Policy (Policies)	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies, Policy [Policy Text Block]	'
	We establish a reserve for matters when a loss is probable and we can reasonably estimate the amount of such loss. For legal actions or proceedings where there is only a reasonable possibility that a loss may be incurred, or where we are not currently able to estimate the reasonably possible loss or range of loss, we do not establish a reserve.
	On a quarterly basis, we review relevant information about all pending legal actions and proceedings for the purpose of evaluating and revising our contingencies, reserves and disclosures.

Consolidations_and_Transfers_o1

Consolidations and Transfers of Financial Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Consolidations and Transfers of Financial Assets [Abstract]	'
Unconsolidated Variable Interest Entities [Table Text Block]	'
	The following table displays the carrying amount and classification of our assets and liabilities that relate to our involvement with unconsolidated mortgage-backed trusts as of June 30, 2014 and December 31, 2013, as well as our maximum exposure to loss and the total assets of these unconsolidated mortgage-backed trusts.
		As of
		June 30, 2014					December 31, 2013
		(Dollars in millions)
	Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts:
	Assets:
	Trading securities:
	Fannie Mae securities		$	5,514				$	5,660
	Non-Fannie Mae securities		7,834					8,559
	Total trading securities		13,348					14,219
	Available-for-sale securities:
	Fannie Mae securities		5,462					5,866
	Non-Fannie Mae securities		24,981					27,441
	Total available-for-sale securities		30,443					33,307
	Other assets		118					119
	Other liabilities		(1,600		)			(1,668		)
	Net carrying amount		$	42,309				$	45,977
	Maximum exposure to loss(1)		$	49,596				$	54,148
	Total assets of unconsolidated mortgage-backed trusts		$	284,852				$	313,202
	__________
	(1)	Our maximum exposure to loss generally represents the greater of our recorded investment in the entity or the unpaid principal balance of the assets covered by our guaranty. However, our securities issued by Fannie Mae multi-class resecuritization trusts that are not consolidated do not give rise to any additional exposure to loss as we already consolidate the underlying collateral.
Key Characteristics of the Securities Retained in Unconsolidated Portfolio Securitization Trusts [Table Text Block]	'
	The following table displays some key characteristics of the securities retained in unconsolidated portfolio securitization trusts as of June 30, 2014 and December 31, 2013.
		Fannie Mae Single-class MBS & Fannie Megas				REMICS & SMBS(1)
		(Dollars in millions)
	As of June 30, 2014
	Unpaid principal balance	$	314			$	6,664
	Fair value	350				7,878
	Weighted-average coupon	6.19			%	5.3			%
	Weighted-average loan age	7.9			years	5.7			years
	Weighted-average maturity	21			years	11.1			years
	As of December 31, 2013
	Unpaid principal balance	$	349			$	6,899
	Fair value	383				7,959
	Weighted-average coupon	6.21			%	5.36			%
	Weighted-average loan age	7.4			years	5.4			years
	Weighted-average maturity	21.5			years	12.6			years
	__________
	(1)	Consists of real estate mortgage investment conduits (“REMICs”) and stripped mortgage-backed securities (“SMBS”).

Mortgage_Loans_Tables

Mortgage Loans (Tables)	6 Months Ended
	Jun. 30, 2014
Mortgage Loans on Real Estate [Line Items]	'
Loans in Mortgage Portfolio [Table Text Block]	'
	The following table displays our mortgage loans as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014																		December 31, 2013
		Of Fannie Mae						Of Consolidated Trusts						Total						Of Fannie Mae						Of Consolidated Trusts						Total
		(Dollars in millions)
	Single-family		$	268,114					$	2,561,871					$	2,829,985					$	276,644					$	2,579,024					$	2,855,668
	Multifamily		30,259						151,036						181,295						37,642						146,249						183,891
	Total unpaid principal balance of mortgage loans		298,373						2,712,907						3,011,280						314,286						2,725,273						3,039,559
	Cost basis and fair value adjustments, net		(13,164		)				45,737						32,573						(13,778		)				44,305						30,527
	Allowance for loan losses for loans held for investment		(36,643		)				(2,424		)				(39,067		)				(40,521		)				(3,325		)				(43,846		)
	Total mortgage loans		$	248,566					$	2,756,220					$	3,004,786					$	259,987					$	2,766,253					$	3,026,240
Aging Analysis [Table Text Block]	'
	The following tables display an aging analysis of the total recorded investment in our HFI mortgage loans, excluding loans for which we have elected the fair value option, by portfolio segment and class as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014(1)
		30 - 59 Days						60 - 89 Days Delinquent						Seriously Delinquent(2)						Total Delinquent						Current				Total				Recorded Investment in Loans 90 Days or More Delinquent and Accruing Interest					Recorded Investment in Nonaccrual Loans
		Delinquent
		(Dollars in millions)
	Single-family:
	Primary(3)		$	29,122					$	8,323					$	41,458					$	78,903				$	2,560,063			$	2,638,966				$	57			$	49,689
	Government(4)		63						24						330						417					46,586				47,003					330				—
	Alt-A		4,227						1,469						13,220						18,916					100,616				119,532					9				14,677
	Other(5)		1,678						562						4,387						6,627					42,225				48,852					18				4,899
	Total single-family		35,090						10,378						59,395						104,863					2,749,490				2,854,353					414				69,265
	Multifamily(6)		59						N/A						172						231					182,715				182,946					—				1,617
	Total		$	35,149					$	10,378					$	59,567					$	105,094				$	2,932,205			$	3,037,299				$	414			$	70,882
		As of December 31, 2013(1)
		30 - 59 Days						60 - 89 Days Delinquent						Seriously Delinquent(2)						Total Delinquent						Current				Total				Recorded Investment in Loans 90 Days or More Delinquent and Accruing Interest					Recorded Investment in Nonaccrual Loans
		Delinquent
		(Dollars in millions)
	Single-family:
	Primary(3)		$	32,371					$	9,755					$	48,345					$	90,471				$	2,558,826			$	2,649,297				$	81			$	57,973
	Government(4)		66						32						346						444					48,150				48,594					346				—
	Alt-A		4,748						1,692						15,425						21,865					105,644				127,509					11				17,102
	Other(5)		1,940						659						5,404						8,003					45,288				53,291					22				5,999
	Total single-family		39,125						12,138						69,520						120,783					2,757,908				2,878,691					460				81,074
	Multifamily(6)		59						N/A						186						245					185,733				185,978					—				2,209
	Total		$	39,184					$	12,138					$	69,706					$	121,028				$	2,943,641			$	3,064,669				$	460			$	83,283
	__________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
	(2)	Single-family seriously delinquent loans are loans that are 90 days or more past due or in the foreclosure process. Multifamily seriously delinquent loans are loans that are 60 days or more past due.
	(3)	Consists of mortgage loans that are not included in other loan classes.
	(4)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A. Primarily consists of reverse mortgages which, due to their nature, are not aged and are included in the current column.
	(5)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
	(6)	Multifamily loans 60-89 days delinquent are included in the seriously delinquent column.
Individually Impaired Loans [Table Text Block]	'
	The following tables display the total unpaid principal balance, recorded investment and related allowance as of June 30, 2014 and December 31, 2013, and interest income recognized and average recorded investment for the three and six months ended June 30, 2014 and 2013, for individually impaired loans.
		As of
		June 30, 2014																				December 31, 2013
		Unpaid Principal Balance						Total Recorded Investment (1)						Related Allowance for Loan Losses				Related Allowance for Accrued Interest Receivable				Unpaid Principal Balance						Total Recorded Investment (1)						Related Allowance for Loan Losses			Related Allowance for Accrued Interest Receivable
		(Dollars in millions)
	Individually impaired loans:
	With related allowance recorded:
	Single-family:
	Primary(2)		$	128,363					$	122,031				$	22,370			$	363				$	130,080					$	123,631				$	24,145		$	430
	Government(3)		279						283					42				12					213						210					35			5
	Alt-A		36,695						33,817					8,673				160					37,356						34,479					9,364			187
	Other(4)		15,323						14,541					3,539				46					15,789						15,023					3,879			56
	Total single-family		180,660						170,672					34,624				581					183,438						173,343					37,423			678
	Multifamily		1,715						1,729					249				8					2,257						2,276					306			10
	Total individually impaired loans with related allowance recorded		182,375						172,401					34,873				589					185,695						175,619					37,729			688
	With no related allowance recorded:(5)
	Single-family:
	Primary(2)		15,531						14,013					—				—					14,076						12,305					—			—
	Government(3)		61						56					—				—					120						120					—			—
	Alt-A		3,476						2,705					—				—					3,290						2,428					—			—
	Other(4)		1,099						949					—				—					1,039						868					—			—
	Total single-family		20,167						17,723					—				—					18,525						15,721					—			—
	Multifamily		1,613						1,622					—				—					1,927						1,939					—			—
	Total individually impaired loans with no related allowance recorded		21,780						19,345					—				—					20,452						17,660					—			—
	Total individually impaired loans(6)		$	204,155					$	191,746				$	34,873			$	589				$	206,147					$	193,279				$	37,729		$	688
		For the Three Months Ended June 30,
		2014																		2013
		Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis						Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis
		(Dollars in millions)
	Individually impaired loans:
	With related allowance recorded:
	Single-family:
	Primary(2)		$	122,791					$	1,093					$	121					$	125,689					$	1,093					$	152
	Government(3)		281						3						—						214						2						—
	Alt-A		34,029						267						22						35,376						275						35
	Other(4)		14,669						102						9						15,700						108						15
	Total single-family		171,770						1,465						152						176,979						1,478						202
	Multifamily		1,813						23						—						2,704						36						1
	Total individually impaired loans with related allowance recorded		173,583						1,488						152						179,683						1,514						203
	With no related allowance recorded:(5)
	Single-family:
	Primary(2)		13,413						205						53						10,301						283						57
	Government(3)		56						2						—						112						2						—
	Alt-A		2,636						43						10						1,972						55						12
	Other(4)		927						13						3						661						23						5
	Total single-family		17,032						263						66						13,046						363						74
	Multifamily		1,668						20						—						1,666						25						—
	Total individually impaired loans with no related allowance recorded		18,700						283						66						14,712						388						74
	Total individually impaired loans(6)		$	192,283					$	1,771					$	218					$	194,395					$	1,902					$	277
		For the Six Months Ended June 30,
		2014																		2013
		Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis						Average Recorded Investment						Total Interest Income Recognized (7)						Interest Income Recognized on a Cash Basis
		(Dollars in millions)
	Individually impaired loans:
	With related allowance recorded:
	Single-family:
	Primary(2)		$	123,066					$	2,187					$	261					$	125,663					$	2,195					$	325
	Government(3)		257						6						—						211						5						—
	Alt-A		34,178						537						50						35,422						552						74
	Other(4)		14,787						205						20						15,830						217						29
	Total single-family		172,288						2,935						331						177,126						2,969						428
	Multifamily		1,967						46						—						2,628						67						1
	Total individually impaired loans with related allowance recorded		174,255						2,981						331						179,754						3,036						429
With no related allowance recorded:(5)
Single-family:
Primary(2)		13,055						390						101						10,688						924						116
Government(3)		76						3						—						110						4						—
Alt-A		2,576						84						20						2,049						230						22
Other(4)		910						24						5						671						86						10
Total single-family		16,617						501						126						13,518						1,244						148
Multifamily		1,758						40						—						1,800						47						1
Total individually impaired loans with no related allowance recorded		18,375						541						126						15,318						1,291						149
Total individually impaired loans(6)		$	192,630					$	3,522					$	457					$	195,072					$	4,327					$	578
__________
(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
(2)	Consists of mortgage loans that are not included in other loan classes.
(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
(5)	The discounted cash flows or collateral value equals or exceeds the carrying value of the loan and, as such, no valuation allowance is required.
(6)	Includes single-family loans restructured in a TDR with a recorded investment of $187.1 billion and $187.6 billion as of June 30, 2014 and December 31, 2013, respectively. Includes multifamily loans restructured in a TDR with a recorded investment of $880 million and $911 million as of June 30, 2014 and December 31, 2013, respectively.
(7)	Total single-family interest income recognized of $1.7 billion and $1.8 billion for the three months ended June 30, 2014 and 2013, respectively, consists of $1.4 billion of contractual interest for both periods and $285 million and $410 million of effective yield adjustments, respectively. Total single-family interest income recognized of $3.4 billion and $4.2 billion for the six months ended June 30, 2014 and 2013, respectively, consists of $2.9 billion of contractual interest for both periods and $560 million and $1.3 billion of effective yield adjustments, respectively.
Troubled Debt Restructurings Activity [Table Text Block]	'
	The following table displays the number of loans and recorded investment in loans restructured in a TDR for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,
		2014											2013
		Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
		(Dollars in millions)
	Single-family:
	Primary(2)		24,932					$	3,564					31,304					$	4,833
	Government(3)		111					13						90					10
	Alt-A		3,660					614						5,175					947
	Other(4)		872					179						1,641					370
	Total single-family		29,575					4,370						38,210					6,160
	Multifamily		3					4						17					135
	Total troubled debt restructurings		29,578					$	4,374					38,227					$	6,295
		For the Six Months Ended June 30,
		2014											2013
		Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
		(Dollars in millions)
	Single-family:
	Primary(2)		53,774					$	7,674					69,555					$	10,477
	Government(3)		173					21						180					21
	Alt-A		8,056					1,354						12,285					2,170
	Other(4)		1,910					398						3,698					822
	Total single-family		63,913					9,447						85,718					13,490
	Multifamily		9					38						25					168
	Total troubled debt restructurings		63,922					$	9,485					85,743					$	13,658
	__________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Based on the nature of our modification programs, which do not include principal or past-due interest forgiveness, there is not a material difference between the recorded investment in our loans pre- and post- modification, therefore amounts represent recorded investment post-modification.
	(2)	Consists of mortgage loans that are not included in other loan classes.
	(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
	(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
	The following table displays the number of loans and recorded investment in loans that had a payment default for the three and six months ended June 30, 2014 and 2013 and were restructured in a TDR in the twelve months prior to the payment default. For purposes of this disclosure, we define loans that had a payment default as: single-family and multifamily loans with completed TDRs that liquidated during the period, either through foreclosure, deed-in-lieu of foreclosure or a short sale; single-family loans with completed modifications that are two or more months delinquent during the period; or multifamily loans with completed modifications that are one or more months delinquent during the period.
		For the Three Months Ended June 30,
		2014											2013
		Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
		(Dollars in millions)
	Single-family:
	Primary(2)		8,190					$	1,251					11,320					$	1,749
	Government(3)		18					1						31					4
	Alt-A		1,396					252						2,584					466
	Other(4)		420					89						852					195
	Total single-family		10,024					1,593						14,787					2,414
	Multifamily		1					3						3					5
	Total TDRs that subsequently defaulted		10,025					$	1,596					14,790					$	2,419
		For the Six Months Ended June 30,
		2014											2013
		Number of Loans					Recorded Investment(1)						Number of Loans					Recorded Investment(1)
		(Dollars in millions)
	Single-family:
	Primary(2)		16,788					$	2,561					23,380					$	3,616
	Government(3)		36					3						60					8
	Alt-A		2,840					512						5,256					950
	Other(4)		924					204						1,675					380
	Total single-family		20,588					3,280						30,371					4,954
	Multifamily		5					17						6					20
	Total TDRs that subsequently defaulted		20,593					$	3,297					30,377					$	4,974
	__________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Represents our recorded investment in the loan at time of payment default.
	(2)	Consists of mortgage loans that are not included in other loan classes.
	(3)	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
	(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
Single-Family [Member]	'
Mortgage Loans on Real Estate [Line Items]	'
Credit Quality Indicators [Table Text Block]	'
	The following table displays the total recorded investment in our single-family HFI loans, excluding loans for which we have elected the fair value option, by class and credit quality indicator as of June 30, 2014 and December 31, 2013. The single-family credit quality indicator is based on available data through the end of each period presented.
		As of
		June 30, 2014(1)(2)														December 31, 2013(1)(2)
		Primary(3)				Alt-A				Other(4)						Primary(3)				Alt-A				Other(4)
		(Dollars in millions)
	Estimated mark-to-market loan-to-value ratio:(5)
	Less than or equal to 80%	$	2,135,261			$	62,455				$	24,320				$	2,073,079			$	61,670				$	24,112
	Greater than 80%  and less than or equal to 90%	256,754				15,978					6,494					276,011				16,794					6,947
	Greater than 90%  and less than or equal to 100%	131,666				13,366					5,760					153,474				14,709					6,402
	Greater than 100% and less than or equal to 110%	49,148				9,783					4,327					59,630				11,006					5,146
	Greater than 110%  and less than or equal to 120%	27,280				6,651					3,069					33,954				7,742					3,691
	Greater than 120%  and less than or equal to 125%	8,908				2,418					1,054					11,256				2,951					1,406
	Greater than 125%	29,949				8,881					3,828					41,893				12,637					5,587
	Total	$	2,638,966			$	119,532				$	48,852				$	2,649,297			$	127,509				$	53,291
	__________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
	(2)	Excludes $47.0 billion and $48.6 billion as of June 30, 2014 and December 31, 2013, respectively, of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A loans. The segment class is primarily reverse mortgages for which we do not calculate an estimated mark-to-market LTV ratio.
	(3)	Consists of mortgage loans that are not included in other loan classes.
	(4)	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
	(5)	The aggregate estimated mark-to-market LTV ratio is based on the unpaid principal balance of the loan as of the end of each reported period divided by the estimated current value of the property, which we calculate using an internal valuation model that estimates periodic changes in home value.
Multifamily [Member]	'
Mortgage Loans on Real Estate [Line Items]	'
Credit Quality Indicators [Table Text Block]	'
	The following table displays the total recorded investment in our multifamily HFI loans, excluding loans for which we have elected the fair value option, by credit quality indicator as of June 30, 2014 and December 31, 2013. The multifamily credit quality indicator is based on available data through the end of each period presented.
		As of
		June 30,						December 31,
		2014(1)						2013(1)
		(Dollars in millions)
	Credit risk profile by internally assigned grade:(2)
	Pass		$	174,656					$	176,528
	Special Mention		2,523						2,234
	Substandard		5,346						6,758
	Doubtful		421						458
	Total		$	182,946					$	185,978
	_________
	(1)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
	(2)	Pass (loan is current and adequately protected by the current financial strength and debt service capacity of the borrower); special mention (loan with signs of potential weakness); substandard (loan with a well defined weakness that jeopardizes timely full repayment); and doubtful (loan with a weakness that makes collection or liquidation in full highly questionable and improbable based on existing conditions and values).

Allowance_for_Loan_Losses_Tabl

Allowance for Loan Losses (Tables)	6 Months Ended
	Jun. 30, 2014
Loans and Leases Receivable, Allowance [Abstract]	'
Allowance for Loan Losses Rollforward by Segment [Table Text Block]	'
	The following table displays changes in single-family, multifamily and total allowance for loan losses for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,
		2014										2013
		Of Fannie Mae			Of Consolidated Trusts				Total			Of Fannie Mae			Of Consolidated Trusts				Total
		(Dollars in millions)
	Single-family allowance for loan losses:
	Beginning balance	$	38,746			$	2,702		$	41,448		$	48,967			$	6,534		$	55,501
	Benefit for loan losses(1)	(1,288		)		(240		)	(1,528		)	(4,098		)		(1,330		)	(5,428		)
	Charge-offs(2)	(1,861		)		(42		)	(1,903		)	(2,015		)		(137		)	(2,152		)
	Recoveries	311				147			458			466				106			572
	Transfers(3)	337				(337		)	—			768				(768		)	—
	Other(4)	155				13			168			244				33			277
	Ending balance	$	36,400			$	2,243		$	38,643		$	44,332			$	4,438		$	48,770
	Multifamily allowance for loan losses:
	Beginning balance	$	258			$	205		$	463		$	586			$	374		$	960
	(Benefit) provision for loan losses(1)	(8		)		(22		)	(30		)	(36		)		15			(21		)
	Charge-offs(2)	(8		)		—			(8		)	(66		)		—			(66		)
	Transfers(3)	2				(2		)	—			8				(8		)	—
	Other(4)	(1		)		—			(1		)	1				(1		)	—
	Ending balance	$	243			$	181		$	424		$	493			$	380		$	873
	Total allowance for loan losses:
	Beginning balance	$	39,004			$	2,907		$	41,911		$	49,553			$	6,908		$	56,461
	Benefit for loan losses(1)	(1,296		)		(262		)	(1,558		)	(4,134		)		(1,315		)	(5,449		)
	Charge-offs(2)(5)	(1,869		)		(42		)	(1,911		)	(2,081		)		(137		)	(2,218		)
	Recoveries	311				147			458			466				106			572
	Transfers(3)	339				(339		)	—			776				(776		)	—
	Other(4)	154				13			167			245				32			277
	Ending balance	$	36,643			$	2,424		$	39,067		$	44,825			$	4,818		$	49,643
		For the Six Months Ended June 30,
		2014										2013
		Of Fannie Mae			Of Consolidated Trusts				Total			Of Fannie Mae			Of Consolidated Trusts				Total
		(Dollars in millions)
	Single-family allowance for loan losses:
	Beginning balance	$	40,202			$	3,105		$	43,307		$	49,848			$	7,839		$	57,687
	Benefit for loan losses(1)	(2,170		)		(202		)	(2,372		)	(4,534		)		(1,733		)	(6,267		)
	Charge-offs(2)	(3,308		)		(143		)	(3,451		)	(4,685		)		(186		)	(4,871		)
	Recoveries	631				218			849			1,493				351			1,844
	Transfers(3)	757				(757		)	—			1,891				(1,891		)	—
	Other(4)	288				22			310			319				58			377
	Ending balance	$	36,400			$	2,243		$	38,643		$	44,332			$	4,438		$	48,770
	Multifamily allowance for loan losses:
	Beginning balance	$	319			$	220		$	539		$	671			$	437		$	1,108
	Benefit for loan losses(1)	(20		)		(38		)	(58		)	(127		)		(39		)	(166		)
	Charge-offs(2)	(59		)		—			(59		)	(67		)		—			(67		)
	Transfers(3)	2				(2		)	—			17				(17		)	—
	Other(4)	1				1			2			(1		)		(1		)	(2		)
	Ending balance	$	243			$	181		$	424		$	493			$	380		$	873
	Total allowance for loan losses:
	Beginning balance	$	40,521			$	3,325		$	43,846		$	50,519			$	8,276		$	58,795
	Benefit for loan losses(1)	(2,190		)		(240		)	(2,430		)	(4,661		)		(1,772		)	(6,433		)
	Charge-offs(2)(5)	(3,367		)		(143		)	(3,510		)	(4,752		)		(186		)	(4,938		)
	Recoveries	631				218			849			1,493				351			1,844
	Transfers(3)	759				(759		)	—			1,908				(1,908		)	—
	Other(4)	289				23			312			318				57			375
	Ending balance	$	36,643			$	2,424		$	39,067		$	44,825			$	4,818		$	49,643
	__________
	(1)	(Benefit) provision for loan losses is included in “Benefit for credit losses” in our condensed consolidated statements of operations and comprehensive income.
	(2)	While we purchase the substantial majority of loans that are four or more months delinquent from our MBS trusts, we do not exercise this option to purchase loans during a forbearance period. Charge-offs of consolidated trusts generally represent loans that remained in our consolidated trusts at the time of default.
	(3)	Includes transfers from trusts for delinquent loan purchases.
	(4)	Amounts represent the net activity recorded in our allowances for accrued interest receivable and preforeclosure property taxes and insurance receivable from borrowers. The (benefit) provision for loan losses, charge-offs, recoveries and transfer activity included in this table reflect all changes for both the allowance for loan losses and the valuation allowances for accrued interest and preforeclosure property taxes and insurance receivable that relate to the mortgage loans.
	(5)	Total charge-offs include accrued interest of $75 million and $122 million for the three months ended June 30, 2014 and 2013, respectively, and $169 million and $237 million for the six months ended June 30, 2014 and 2013, respectively.
Allowance for Loan Losses and Total Recorded Investment in HFI Loans [Table Text Block]	'
	The following table displays the allowance for loan losses and total recorded investment in our HFI loans, excluding loans for which we have elected the fair value option, by impairment or reserve methodology and portfolio segment as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014										December 31, 2013
		Single-Family			Multifamily				Total			Single-Family			Multifamily				Total
		(Dollars in millions)
	Allowance for loan losses by segment:
	Individually impaired loans(1)	$	34,624			$	249		$	34,873		$	37,423			$	306		$	37,729
	Collectively reserved loans	4,019				175			4,194			5,884				233			6,117
	Total allowance for loan losses	$	38,643			$	424		$	39,067		$	43,307			$	539		$	43,846
	Recorded investment in loans by segment:(2)
	Individually impaired loans(1)	$	188,395			$	3,351		$	191,746		$	189,064			$	4,215		$	193,279
	Collectively reserved loans	2,665,958				179,595			2,845,553			2,689,627				181,763			2,871,390
	Total recorded investment in loans	$	2,854,353			$	182,946		$	3,037,299		$	2,878,691			$	185,978		$	3,064,669
	__________
	(1)	Includes acquired credit-impaired loans.
	(2)	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.

Investments_in_Securities_Tabl

Investments in Securities (Tables)	6 Months Ended
	Jun. 30, 2014
Investments, Debt and Equity Securities [Abstract]	'
Investments In Trading Securities [Table Text Block]	'
	The following table displays our investments in trading securities as of June 30, 2014 and December 31, 2013.
		As of
		30-Jun-14						31-Dec-13
		(Dollars in millions)
	Mortgage-related securities:
	Fannie Mae		$	5,686					$	5,870
	Freddie Mac		1,766						1,839
	Ginnie Mae		234						407
	Alt-A private-label securities		1,194						1,516
	Subprime private-label securities		1,282						1,448
	CMBS		2,641						2,718
	Mortgage revenue bonds		643						565
	Other mortgage-related securities		101						99
	Total mortgage-related securities		13,547						14,462
	U.S. Treasury securities		13,083						16,306
	Total trading securities		$	26,630					$	30,768
Schedule of Trading Securities Gains (Losses), Net [Table Text Block]	'
	The following table displays information about our net trading gains and losses for the three and six months ended June 30, 2014 and 2013.
		For the Three								For the Six
		Months Ended								Months Ended
		June 30,								June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Net trading gains (losses)	$	249			$	(228	)		$	394			$	168
	Net trading gains (losses) recognized in the period related to securities still held at period end	233				(273		)		353				125
Schedule of Realized Gain (Loss) [Table Text Block]	'
	The following table displays the gross realized gains, losses and proceeds on sales of AFS securities for the three and six months ended June 30, 2014 and 2013.
		For the Three								For the Six
		Months Ended								Months Ended
		June 30,								June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Gross realized gains	$	396			$	173			$	399			$	182
	Gross realized losses	—				53				2				57
	Total proceeds(1)	1,705				1,676				1,740				1,770
	__________
	s
	(1)	Excludes proceeds from the initial sale of securities from new portfolio securitizations included in “Note 2, Consolidations and Transfers of Financial Assets.”
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]	'
	The following tables display the amortized cost, gross unrealized gains and losses, and fair value by major security type for AFS securities we held as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014
		Total Amortized Cost(1)						Gross Unrealized Gains						Gross Unrealized Losses - OTTI(2)						Gross Unrealized Losses - Other(3)						Total Fair Value
		(Dollars in millions)
	Fannie Mae		$	5,663					$	385					$	—					$	(26	)			$	6,022
	Freddie Mac		5,735						467						—						—					6,202
	Ginnie Mae		461						67						—						—					528
	Alt-A private-label securities		5,479						1,220						(18		)				—					6,681
	Subprime private-label securities		4,688						1,057						(19		)				(21		)			5,705
	CMBS		1,427						81						—						—					1,508
	Mortgage revenue bonds		4,669						79						(126		)				(62		)			4,560
	Other mortgage-related securities		2,781						214						(24		)				(151		)			2,820
	Total		$	30,903					$	3,570					$	(187	)				$	(260	)			$	34,026
		As of December 31, 2013
		Total Amortized Cost(1)						Gross Unrealized Gains						Gross Unrealized Losses - OTTI(2)						Gross Unrealized Losses - Other(3)						Total Fair Value
		(Dollars in millions)
	Fannie Mae		$	6,227					$	390					$	—					$	(44	)			$	6,573
	Freddie Mac		6,365						477						—						—					6,842
	Ginnie Mae		512						76						—						—					588
	Alt-A private-label securities		6,240						1,151						(40		)				(2		)			7,349
	Subprime private-label securities		6,232						991						(102		)				(53		)			7,068
	CMBS		1,526						80						—						—					1,606
	Mortgage revenue bonds		5,645						35						(228		)				(196		)			5,256
	Other mortgage-related securities		2,943						164						(15		)				(203		)			2,889
	Total		$	35,690					$	3,364					$	(385	)				$	(498	)			$	38,171
	__________
	(1)	Amortized cost consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments as well as net other-than-temporary impairments (“OTTI”) recognized in our condensed consolidated statements of operations and comprehensive income.
	(2)	Represents the noncredit component of other-than-temporary impairments losses recorded in “Accumulated other comprehensive income” in our condensed consolidated balance sheets, as well as cumulative changes in fair value of securities for which we previously recognized the credit component of other-than-temporary impairments.
	(3)	Represents the gross unrealized losses on securities for which we have not recognized other-than-temporary impairments.
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block]	'
	The following tables display additional information regarding gross unrealized losses and fair value by major security type for AFS securities in an unrealized loss position that we held as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014
		Less Than 12 Consecutive Months										12 Consecutive Months or Longer
		Gross Unrealized Losses						Fair Value				Gross Unrealized Losses						Fair Value
		(Dollars in millions)
	Fannie Mae		$	(4	)			$	284				$	(22	)			$	673
	Alt-A private-label securities		(3		)			121					(15		)			113
	Subprime private-label securities		(2		)			72					(38		)			618
	Mortgage revenue bonds		(2		)			66					(186		)			1,396
	Other mortgage-related securities		—					5					(175		)			1,050
	Total		$	(11	)			$	548				$	(436	)			$	3,850
		As of December 31, 2013
		Less Than 12 Consecutive Months										12 Consecutive Months or Longer
		Gross Unrealized Losses						Fair Value				Gross Unrealized Losses						Fair Value
		(Dollars in millions)
	Fannie Mae		$	(40	)			$	975				$	(4	)			$	126
	Alt-A private-label securities		(12		)			490					(30		)			308
	Subprime private-label securities		(24		)			448					(131		)			1,332
	Mortgage revenue bonds		(147		)			1,662					(277		)			970
	Other mortgage-related securities		—					5					(218		)			1,066
	Total		$	(223	)			$	3,580				$	(660	)			$	3,802
Schedule of Modeled Attributes Used to Determine Potential Cash Shortfalls [Table Text Block]	'
	The following table displays the modeled attributes, including default rates and severities, which were used to determine as of June 30, 2014 whether our senior interests in certain non-agency mortgage-related securities (including those we intend to sell) will experience a cash shortfall. An estimate of voluntary prepayment rates is also an input to the present value of expected losses.
		As of June 30, 2014
						Alt-A
		Subprime				Option ARM						Fixed Rate						Variable Rate						Hybrid Rate
		(Dollars in millions)
	Vintage Year
	2004 & Prior:
	Unpaid principal balance	$	117				$	117					$	920					$	133					$	328
	Weighted average collateral default(1)	26.5		%			23.9		%				9.5		%				20.8		%				13.3		%
	Weighted average collateral severities(2)	55.2					54.5						52						40.8						38.5
	Weighted average voluntary prepayment rates(3)	10.1					9.7						13.4						9.9						10.2
	Average credit enhancement(4)	38.4					4.1						10.9						21.3						9.4
	2005:00:00
	Unpaid principal balance	$	41				$	472					$	828					$	384					$	1,348
	Weighted average collateral default(1)	49		%			31.9		%				22.9		%				33		%				26.4		%
	Weighted average collateral severities(2)	60					53.5						54						47.7						44.2
	Weighted average voluntary prepayment rates(3)	2.9					7.5						10.4						8.5						9.1
	Average credit enhancement(4)	47.9					8.9						0.6						12.6						2.8
	2006:00:00
	Unpaid principal balance	$	7,527				$	690					$	393					$	1,088					$	1,193
	Weighted average collateral default(1)	53		%			42.1		%				24.4		%				36.3		%				18.1		%
	Weighted average collateral severities(2)	61.4					48.3						55.2						47.7						43.7
	Weighted average voluntary prepayment rates(3)	2.4					6.1						8.3						7.7						10.1
	Average credit enhancement(4)	10.3					2.9						0.1						0.7						—
	2007 & After:
	Unpaid principal balance	$	341				$	—					$	—					$	—					$	83
	Weighted average collateral default(1)	50.4		%			N/A						N/A						N/A						21.9		%
	Weighted average collateral severities(2)	28					N/A						N/A						N/A						39.9
	Weighted average voluntary prepayment rates(3)	1.4					N/A						N/A						N/A						9.9
	Average credit enhancement(4)	20.3					N/A						N/A						N/A						20.4
	Total:
	Unpaid principal balance	$	8,026				$	1,279					$	2,141					$	1,605					$	2,952
	Weighted average collateral default(1)	52.5		%			36.7		%				17.4		%				34.2		%				21.5		%
	Weighted average collateral severities(2)	60					50.3						53.8						47.3						43.5
	Weighted average voluntary prepayment rates(3)	2.5					7						11.3						8.1						9.6
	Average credit enhancement(4)	11.4					5.2						4.9						5.3						2.9
	__________
	(1)	The expected remaining cumulative default rate of the collateral pool backing the securities, as a percentage of the current collateral unpaid principal balance, weighted by security unpaid principal balance.
	(2)	The expected remaining loss given default of the collateral pool backing the securities, calculated as the ratio of remaining cumulative loss divided by cumulative defaults, weighted by security unpaid principal balance.
	(3)	The average monthly voluntary prepayment rate, weighted by security unpaid principal balance.
	(4)	The average percent current credit enhancement provided by subordination of other securities. Excludes excess interest projections and monoline bond insurance.
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table Text Block]	'
	The following table displays activity related to the unrealized credit loss component on debt securities held by us and recognized in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended								For the Six Months Ended
		June 30,								June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Balance, beginning of period	$	7,096			$	9,136			$	7,904			$	9,214
	Additions for the credit component on debt securities for which OTTI was not previously recognized	—				2				1				7
	Additions for the credit component on debt securities for which OTTI was previously recognized	8				4				47				8
	Reductions for securities no longer in portfolio at period end	(384		)		(81		)		(437		)		(83		)
	Reductions for securities which we intend to sell or it is more likely than not that we will be required to sell before recovery of amortized cost basis	(755		)		—				(1,453		)		—
	Reductions for amortization resulting from changes in cash flows expected to be collected over the remaining life of the securities	(94		)		(97		)		(191		)		(182		)
	Balance, end of period	$	5,871			$	8,964			$	5,871			$	8,964
Investments Classified by Contractual Maturity Date [Table Text Block]	'
	The following table displays the amortized cost and fair value of our AFS securities by major security type and remaining contractual maturity, assuming no principal prepayments, as of June 30, 2014. The contractual maturity of mortgage-backed securities is not a reliable indicator of their expected life because borrowers generally have the right to prepay their obligations at any time.
		As of June 30, 2014
		Total Amortized Cost						Total				One Year or Less										After One Year Through Five Years								After Five Years Through Ten Years					After Ten Years
								Fair
								Value				Amortized Cost						Fair Value				Amortized Cost						Fair Value		Amortized Cost			Fair Value		Amortized Cost			Fair Value
		(Dollars in millions)
	Fannie Mae		$	5,663				$	6,022				$	—				$	—				$	321				$	339		$	284	$	307		$	5,058	$	5,376
	Freddie Mac		5,735					6,202					—					—					367					389			590		646			4,778		5,167
	Ginnie Mae		461					528					—					—					—					—			66		75			395		453
	Alt-A private-label securities		5,479					6,681					—					—					—					—			—		—			5,479		6,681
	Subprime private-label securities		4,688					5,705					—					—					—					—			—		—			4,688		5,705
	CMBS		1,427					1,508					—					—					1,345					1,424			—		—			82		84
	Mortgage revenue bonds		4,669					4,560					26					27					209					212			467		470			3,967		3,851
	Other mortgage-related securities		2,781					2,820					—					—					—					3			36		39			2,745		2,778
	Total		$	30,903				$	34,026				$	26				$	27				$	2,242				$	2,367		$	1,443	$	1,537		$	27,192	$	30,095

Financial_Guarantees_Tables

Financial Guarantees (Tables)	6 Months Ended
	Jun. 30, 2014
Guarantor Obligations [Line Items]	'
Financial Guarantees and Maximum Recovery [Table Text Block]	'
	The following table displays our maximum exposure, guaranty obligation recognized in our condensed consolidated balance sheets and the maximum potential recovery from third parties through available credit enhancements and recourse related to our financial guarantees as of June 30, 2014 and December 31, 2013.
		As of
		30-Jun-14													31-Dec-13
		Maximum Exposure(1)			Guaranty Obligation				Maximum Recovery(2)					Maximum Exposure(1)			Guaranty Obligation			Maximum Recovery(2)
		(Dollars in millions)
	Non-consolidated Fannie Mae MBS	$	18,257			$	222			$	10,332				$	19,317		$	232		$	10,541
	Other guaranty arrangements(3)	28,951				231				4,569					30,598			253			4,525
	Total	$	47,208			$	453			$	14,901				$	49,915		$	485		$	15,066
	__________
	(1)	Primarily consists of the unpaid principal balance of the underlying mortgage loans.
	(2)	Recoverability of such credit enhancements and recourse is subject to, among other factors, our mortgage insurers’ and financial guarantors’ ability to meet their obligations to us. For information on our mortgage insurers, see “Note 14, Concentrations of Credit Risk.”
	(3)	Primarily consists of credit enhancements, long-term standby commitments, and our commitment under the TCLF program.
Single-Family [Member]	'
Guarantor Obligations [Line Items]	'
Delinquency Status Guaranty Book of Business [Table Text Block]	'
	The following tables display the current delinquency status and certain higher risk characteristics of our single-family conventional and total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014(1)							December 31, 2013(1)
		30 Days Delinquent		60 Days Delinquent			Seriously Delinquent(2)		30 Days Delinquent			60 Days Delinquent			Seriously Delinquent(2)
	Percentage of single-family conventional guaranty book of business(3)	1.27	%	0.38	%		2.18	%	1.41	%		0.44	%		2.54	%
	Percentage of single-family conventional loans(4)	1.46		0.42			2.05		1.64			0.49			2.38
Risk Characteristics Guaranty Book of Business [Table Text Block]	'
		As of
		June 30, 2014(1)					December 31, 2013(1)
		Percentage of		Percentage Seriously Delinquent(2)(5)			Percentage of		Percentage Seriously Delinquent(2)(5)
		Single-Family					Single-Family
		Conventional					Conventional
		Guaranty Book of Business(3)					Guaranty Book of Business(3)
	Estimated mark-to-market loan-to-value ratio:
	Greater than 100%	6	%	11.4	%		7	%	12.22	%
	Geographical distribution:
	California	20		0.77			20		0.98
	Florida	6		5.46			6		6.89
	Illinois	4		2.6			4		3.12
	New Jersey	4		5.94			4		6.25
	New York	5		4.24			5		4.42
	All other states	61		1.6			61		1.85
	Product distribution:
	Alt-A	4		8.37			5		9.23
	Subprime	*		15.65			*		16.93
	Vintages:
	2005	3		6.47			4		7.26
	2006	3		10.11			3		11.26
	2007	4		11.08			5		12.18
	2008	3		6.27			3		6.69
	All other vintages	87		0.91			85		1.02
	Select combined risk characteristics:
	Original LTV ratio > 90% and FICO score < 620	1		9.34			1		10.9
	__________
	*	Represents less than 0.5% of the single-family conventional guaranty book of business.
	(1)	Consists of the portion of our single-family conventional guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total single-family conventional guaranty book of business as of June 30, 2014 and December 31, 2013.
	(2)	Consists of single-family conventional loans that were 90 days or more past due or in the foreclosure process as of June 30, 2014 and December 31, 2013.
	(3)	Calculated based on the aggregate unpaid principal balance of single-family conventional loans for each category divided by the aggregate unpaid principal balance of loans in our single-family conventional guaranty book of business.
	(4)	Calculated based on the number of single-family conventional loans that were delinquent divided by the total number of loans in our single-family conventional guaranty book of business.
	(5)	Calculated based on the number of single-family conventional loans that were seriously delinquent divided by the total number of single-family conventional loans for each category included in our guaranty book of business.
Multifamily [Member]	'
Guarantor Obligations [Line Items]	'
Delinquency Status Guaranty Book of Business [Table Text Block]	'
		As of
		June 30, 2014(1)(2)					December 31, 2013(1)(2)
		30 Days Delinquent		Seriously Delinquent(3)			30 Days Delinquent		Seriously Delinquent(3)
	Percentage of multifamily guaranty book of business	0.03	%	0.1	%		0.03	%	0.1	%
Risk Characteristics Guaranty Book of Business [Table Text Block]	'
		As of
		June 30, 2014(1)					December 31, 2013(1)
		Percentage of Multifamily Guaranty Book of Business(2)		Percentage Seriously Delinquent(3)(4)			Percentage of Multifamily Guaranty Book of Business(2)		Percentage Seriously Delinquent(3)(4)
	Original LTV ratio:
	Greater than 80%	3	%	0.17	%		3	%	0.23	%
	Less than or equal to 80%	97		0.1			97		0.1
	Current debt service coverage ratio less than 1.0(5)	3		0.95			4		1.09
	__________
	(1)	Consists of the portion of our multifamily guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013 excluding loans that have been defeased.
	(2)	Calculated based on the aggregate unpaid principal balance of multifamily loans for each category divided by the aggregate unpaid principal balance of loans in our multifamily guaranty book of business.
	(3)	Consists of multifamily loans that were 60 days or more past due as of the dates indicated.
	(4)	Calculated based on the unpaid principal balance of multifamily loans that were seriously delinquent divided by the aggregate unpaid principal balance of multifamily loans for each category included in our guaranty book of business.
	(5)	Our estimates of current DSCRs are based on the latest available income information for these properties. Although we use the most recently available results of our multifamily borrowers, there is a lag in reporting, which typically can range from 3 to 6 months but in some cases may be longer.

Acquired_Property_Net_Acquired

Acquired Property Net Acquired Property Net (Tables)	6 Months Ended
	Jun. 30, 2014
Real Estate [Abstract]	'
Activity in acquired property and the related valuation allowance [Table Text Block]	'
	The following table displays the activity in acquired property, and the related valuation allowance, for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,						For the Six Months
								Ended June 30,
		2014			2013			2014			2013
		(Dollars in millions)
	Beginning balance — Acquired property	$	12,744		$	10,719		$	12,307		$	11,158
	Additions	3,425			4,195			7,197			7,969
	Disposals	(3,873		)	(4,108		)	(7,208		)	(8,321		)
	Ending balance — Acquired property	$	12,296		$	10,806		$	12,296		$	10,806
	Beginning balance — Valuation allowance	(784		)	(570		)	(686		)	(669		)
	Decrease (increase) in valuation allowance	48			30			(50		)	129
	Ending balance — Valuation allowance	(736		)	(540		)	(736		)	(540		)
	Ending balance — Acquired property, net	$	11,560		$	10,266		$	11,560		$	10,266

ShortTerm_Borrowings_and_LongT1

Short-Term Borrowings and Long-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Short-Term Borrowings [Table Text Block]	'
	The following table displays our outstanding short-term borrowings (borrowings with an original contractual maturity of one year or less) and weighted-average interest rates of these borrowings as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014									December 31, 2013
		Outstanding					Weighted- Average Interest Rate(1)				Outstanding					Weighted- Average Interest Rate(1)
			(Dollars in millions)
	Fixed-rate short-term debt:
	Discount notes(2)		$	90,926				0.1	%			$	71,933				0.12	%
	Foreign exchange discount notes(3)		—					—				362					1.07
	Total short-term debt of Fannie Mae		90,926					0.1				72,295					0.13
	Debt of consolidated trusts		1,844					0.1				2,154					0.09
	Total short-term debt		$	92,770				0.1	%			$	74,449				0.13	%
	__________
	(1)	Includes the effects of discounts, premiums and other cost basis adjustments.
	(2)	Represents unsecured general obligations with maturities ranging from overnight to 360 days from the date of issuance.
	(3)	Represents foreign exchange discount notes issued in the Euro commercial paper market with maturities ranging from 5 to 360 days which enable investors to hold short-term investments in different currencies. We do not incur foreign exchange risk on these transactions, as we simultaneously enter into foreign currency swaps that have the effect of converting debt that we issue in foreign denominated currencies into U.S. dollars.
Long-Term Debt [Table Text Block]	'
	The following table displays our outstanding long-term debt as of June 30, 2014 and December 31, 2013.
		As of
		June 30, 2014									December 31, 2013
		Maturities		Outstanding					Weighted- Average Interest Rate(1)		Maturities		Outstanding					Weighted- Average Interest Rate(1)
		(Dollars in millions)
	Senior fixed:
	Benchmark notes and bonds	2014 - 2030			$	186,556			2.4	%	2014 - 2030			$	212,234			2.45	%
	Medium-term notes(2)	2014 - 2024			124,483				1.36		2014 - 2023			161,445				1.28
	Foreign exchange notes and bonds	2021 - 2028			680				5.25		2021 - 2028			682				5.41
	Other(3)	2014 - 2038			36,061				5.02		2014 - 2038			38,444				4.99
	Total senior fixed				347,780				2.31					412,805				2.24
	Senior floating:
	Medium-term notes(2)	2014 - 2019			31,493				0.18		2014 - 2019			38,441				0.2
	Other(3)(4)	2020 - 2037			3,432				3.18		2020 - 2037			955				5.18
	Total senior floating				34,925				0.46					39,396				0.32
	Subordinated fixed:
	Qualifying subordinated	—			—				—		2014			1,169				5.27
	Subordinated debentures	2019			3,674				9.92		2019			3,507				9.92
	Total subordinated fixed				3,674				9.92					4,676				8.76
	Secured borrowings(5)	2021 - 2022			230				1.88		2021 - 2022			262				1.86
	Total long-term debt of Fannie Mae(6)				386,609				2.21					457,139				2.14
	Debt of consolidated trusts(3)	2014 - 2054			2,710,166				3.17		2014 - 2053			2,702,935				3.26
	Total long-term debt				$	3,096,775			3.05	%				$	3,160,074			3.1	%
	__________
	(1)	Includes the effects of discounts, premiums and other cost basis adjustments.
	(2)	Includes long-term debt with an original contractual maturity of greater than 1 year and up to 10 years, excluding zero-coupon debt.
	(3)	Includes a portion of structured debt instruments that is reported at fair value.
	(4)	Includes credit risk sharing securities issued under our Connecticut Avenue Securities series, which transfers some of the credit risk of our mortgage loans to the investors in these securities.
	(5)	Represents our remaining liability resulting from the transfer of financial assets from our condensed consolidated balance sheets that did not qualify as a sale under the accounting guidance for the transfer of financial instruments.
	(6)	Reported amounts include unamortized discounts and premiums, other cost basis adjustments and fair value adjustments of $4.1 billion and $4.8 billion as of June 30, 2014 and December 31, 2013, respectively.

Derivative_Instruments_Tables

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Notional and Fair Value Position [Table Text Block]	'
	The following table displays the notional amount and estimated fair value of our asset and liability derivative instruments as of June 30, 2014 and December 31, 2013.
		As of June 30, 2014												As of December 31, 2013
		Asset Derivatives						Liability Derivatives						Asset Derivatives					Liability Derivatives
		Notional Amount			Estimated Fair Value			Notional Amount			Estimated Fair Value			Notional Amount		Estimated Fair Value			Notional Amount		Estimated Fair Value
		(Dollars in millions)
	Risk management derivatives:
	Swaps:
	Pay-fixed	$	52,489		$	2,340		$	105,272		$	(6,019	)	$	68,637	$	5,378		$	93,428	$	(4,759	)
	Receive-fixed	66,478			4,179			133,397			(1,629		)	67,527		3,320			156,250		(3,813		)
	Basis	13,914			79			6,850			(1		)	27,014		36			600		—
	Foreign currency	377			139			299			(16		)	389		120			653		(38		)
	Swaptions:
	Pay-fixed	25,150			94			43,525			(264		)	33,400		445			48,025		(600		)
	Receive-fixed	4,500			216			46,525			(721		)	8,000		117			48,025		(484		)
	Other(1)	109			29			37			(1		)	769		28			13		(1		)
	Total gross risk management derivatives	163,017			7,076			335,905			(8,651		)	205,736		9,444			346,994		(9,695		)
	Accrued interest receivable (payable)	—			696			—			(950		)	—		786			—		(930		)
	Netting adjustment(2)	—			(6,897		)	—			9,390			—		(8,422		)	—		9,370
	Total net risk management derivatives	$	163,017		$	875		$	335,905		$	(211	)	$	205,736	$	1,808		$	346,994	$	(1,255	)
	Mortgage commitment derivatives:
	Mortgage commitments to purchase whole loans	$	7,728		$	44		$	235		$	—		$	1,138	$	1		$	4,353	$	(31	)
	Forward contracts to purchase mortgage-related securities	40,214			343			663			(2		)	3,276		4			20,861		(168		)
	Forward contracts to sell mortgage-related securities	484			2			60,336			(523		)	35,423		260			7,886		(15		)
	Total mortgage commitment derivatives	$	48,426		$	389		$	61,234		$	(525	)	$	39,837	$	265		$	33,100	$	(214	)
	Derivatives at fair value	$	211,443		$	1,264		$	397,139		$	(736	)	$	245,573	$	2,073		$	380,094	$	(1,469	)
	__________
	(1)	Includes interest rate caps, futures, swap credit enhancements and mortgage insurance contracts that we account for as derivatives. The mortgage insurance contracts have payment provisions that are not based on a notional amount.
	(2)	The netting adjustment for our risk management derivatives transactions represents the effect of the legal right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received. Cash collateral posted was $3.3 billion and $2.0 billion as of June 30, 2014 and December 31, 2013, respectively. Cash collateral received was $780 million and $1.0 billion as of June 30, 2014 and December 31, 2013, respectively.
Fair Value Gain (Loss), Net [Table Text Block]	'
	The following table displays, by type of derivative instrument, the fair value gains and losses, net on our derivatives for the three and six months ended June 30, 2014 and 2013.
		For the						For the
		Three Months						Six Months
		Ended June 30,						Ended June 30,
		2014			2013			2014			2013
		(Dollars in millions)
	Risk management derivatives:
	Swaps:
	Pay-fixed	$	(2,349	)	$	8,313		$	(4,467	)	$	10,903
	Receive-fixed	1,639			(7,123		)	3,104			(9,033		)
	Basis	8			(45		)	43			(72		)
	Foreign currency	17			(63		)	38			(133		)
	Swaptions:
	Pay-fixed	62			(468		)	(37		)	(451		)
	Receive-fixed	(59		)	247			(101		)	268
	Other	3			11			—			21
	Accrual of periodic settlements:
	Pay-fixed interest-rate swaps	(913		)	(1,211		)	(1,816		)	(2,409		)
	Receive-fixed interest-rate swaps	642			1,012			1,333			1,994
	Other	14			18			27			34
	Total risk management derivatives fair value (losses) gains, net	$	(936	)	$	691		$	(1,876	)	$	1,122
	Mortgage commitment derivatives fair value (losses) gains, net	(310		)	497			(655		)	628
	Total derivatives fair value (losses) gains, net	$	(1,246	)	$	1,188		$	(2,531	)	$	1,750

Earnings_Loss_Per_Share_Tables

Earnings (Loss) Per Share (Tables)	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Schedule of Earnings (Loss) Per Share, Basic and Diluted [Table Text Block]	'
	The following table displays the computation of basic and diluted loss per share of common stock for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,								For the Six Months Ended June 30,
		2014				2013				2014				2013
		(Dollars and shares in millions, except per share amounts)
	Net income		$	3,667			$	10,095			$	8,992			$	68,780
	Less: Net income attributable to noncontrolling interest		(1		)		(11		)		(1		)		(11		)
	Net income attributable to Fannie Mae		3,666				10,084				8,991				68,769
	Dividends distributed or available for distribution to senior preferred stockholder(1)		(3,712		)		(10,243		)		(9,404		)		(69,611		)
	Net loss attributable to common stockholders		$	(46	)		$	(159	)		$	(413	)		$	(842	)
	Weighted-average common shares outstanding—basic and diluted(2)		5,762				5,762				5,762				5,762
	Loss per share: basic and diluted		$	(0.01	)		$	(0.03	)		$	(0.07	)		$	(0.15	)
	__________
	(1)	Represents our dividend payments to Treasury under the terms of the senior preferred stock. Dividends distributed or available for distribution for the three months ended June 30, 2014 (relating to the dividend period for the three months ended September 30, 2014) were calculated based on our net worth as of June 30, 2014 less the applicable capital reserve amount of $2.4 billion and for the six months ended June 30, 2014 we add dividends paid on June 30, 2014 to this amount. Dividends distributed or available for distribution for the three months ended June 30, 2013 (relating to the dividend period for the three months ended September 30, 2013) were calculated based on our net worth as of June 30, 2013 less the applicable capital reserve amount of $3.0 billion and for the six months ended June 30, 2013 we add dividends paid on June 30, 2013 to this amount.
	(2)	Includes 4.6 billion of weighted average shares of common stock that would be issued upon the full exercise of the warrant issued to Treasury from the date the warrant was issued through June 30, 2014.

Segment_Reporting_Tables

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment results [Table Text Block]	'
	The following tables display our business segment financial results for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30, 2014
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest income (loss)	$	5			$	(21	)	$	1,917			$	2,739			$	264		(3)	$	4,904
	Benefit for credit losses	1,603				36			—				—				—				1,639
	Net interest income after benefit for credit losses	1,608				15			1,917				2,739				264				6,543
	Guaranty fee income (expense)(4)	2,893				317			(241		)		(1,452		)	(5)	(1,476		)	(5)	41			(5)
	Investment (losses) gains, net	(1		)		39			1,648				(104		)		(1,076		)	(6)	506
	Net other-than-temporary impairments	—				—			(23		)		—				—				(23		)
	Fair value (losses) gains, net	(2		)		—			(1,098		)		171				(5		)	(7)	(934		)
	Debt extinguishment gains (losses), net	—				—			41				(3		)		—				38
	Gains from partnership investments(8)	—				34			—				—				1				35
	Fee and other income (expense)	181				31			136				(95		)		89				342
	Administrative expenses	(458		)		(75		)	(164		)		—				—				(697		)
	Foreclosed property income	178				36			—				—				—				214
	TCCA fees(4)	(335		)		—			—				—				—				(335		)
	Other expenses	(237		)		(12		)	(57		)		—				(5		)		(311		)
	Income before federal income taxes	3,827				385			2,159				1,256				(2,208		)		5,419
	Provision for federal income taxes	(1,133		)		(9		)	(610		)		—				—				(1,752		)
	Net income	2,694				376			1,549				1,256				(2,208		)		3,667
	Less: Net income attributable to noncontrolling interest	—				—			—				—				(1		)	(9)	(1		)
	Net income attributable to Fannie Mae	$	2,694			$	376		$	1,549			$	1,256			$	(2,209	)		$	3,666
		For the Six Months Ended June 30, 2014
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest (loss) income	$	(43	)		$	(43	)	$	3,747			$	5,437			$	544		(3)	$	9,642
	Benefit for credit losses	2,348				65			—				—				—				2,413
	Net interest income after benefit for credit losses	2,305				22			3,747				5,437				544				12,055
	Guaranty fee income (expense)(4)	5,763				628			(487		)		(2,879		)	(5)	(2,939		)	(5)	86			(5)
	Investment (losses) gains, net	(1		)		42			2,984				(162		)		(2,211		)	(6)	652
	Net other-than-temporary impairments	—				—			(74		)		—				—				(74		)
	Fair value (losses) gains, net	(7		)		—			(2,435		)		219				99			(7)	(2,124		)
	Debt extinguishment gains, net	—				—			34				4				—				38
	Gains from partnership investments(8)	—				79			—				—				1				80
	Fee and other income (expense)	325				55			4,269				(171		)		174				4,652
	Administrative expenses	(908		)		(148		)	(313		)		—				—				(1,369		)
	Foreclosed property income	435				41			—				—				—				476
	TCCA fees(4)	(657		)		—			—				—				—				(657		)
	Other expenses	(392		)		(13		)	(65		)		—				(17		)		(487		)
	Income before federal income taxes	6,863				706			7,660				2,448				(4,349		)		13,328
	Provision for federal income taxes	(2,060		)		—			(2,276		)		—				—				(4,336		)
	Net income	4,803				706			5,384				2,448				(4,349		)		8,992
	Less: Net income attributable to noncontrolling interest	—				—			—				—				(1		)	(9)	(1		)
	Net income attributable to Fannie Mae	$	4,803			$	706		$	5,384			$	2,448			$	(4,350	)		$	8,991
		For the Three Months Ended June 30, 2013(10)
		Business Segments										Other Activity/Reconciling Items
		Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
		(Dollars in millions)
	Net interest (loss) income	$	(50	)		$	(17	)	$	2,680			$	2,621			$	433		(3)	$	5,667
	Benefit for credit losses	5,353				30			—				—				—				5,383
	Net interest income after benefit for credit losses	5,303				13			2,680				2,621				433				11,050
	Guaranty fee income (expense)(4)	2,544				300			(283		)		(1,283		)	(5)	(1,227		)	(5)	51			(5)
	Investment gains (losses), net	1				4			898				(89		)		(524		)	(6)	290
	Net other-than-temporary impairments	—				—			(6		)		—				—				(6		)
	Fair value (losses) gains, net	(1		)		—			841				(214		)		203			(7)	829
	Debt extinguishment gains, net	—				—			3				24				—				27
	Gains from partnership investments(8)	—				104			—				—				11				115
	Fee and other income (expense)	179				38			255				(86		)		48				434
	Administrative expenses	(419		)		(67		)	(140		)		—				—				(626		)
	Foreclosed property income	328				4			—				—				—				332
TCCA fees(4)	(233		)		—			—				—				—				(233		)
Other expenses	(154		)		—			(8		)		—				(21		)		(183		)
Income before federal income taxes	7,548				396			4,240				973				(1,077		)		12,080
Provision for federal income taxes	(1,050		)		(10		)	(925		)		—				—				(1,985		)
Net income	6,498				386			3,315				973				(1,077		)		10,095
Less: Net income attributable to noncontrolling interest	—				—			—				—				(11		)	(9)	(11		)
Net income attributable to Fannie Mae	$	6,498			$	386		$	3,315			$	973			$	(1,088	)		$	10,084
	For the Six Months Ended June 30, 2013(10)
	Business Segments										Other Activity/Reconciling Items
	Single-Family			Multifamily				Capital Markets			Consolidated Trusts(1)					Eliminations/ Adjustments(2)				Total Results
	(Dollars in millions)
Net interest income (loss)	$	470			$	(28	)	$	5,422			$	5,218			$	889		(3)	$	11,971
Benefit for credit losses	6,134				206			—				—				—				6,340
Net interest income after benefit for credit losses	6,604				178			5,422				5,218				889				18,311
Guaranty fee income (expense)(4)	4,919				591			(582		)		(2,487		)	(5)	(2,336		)	(5)	105			(5)
Investment gains (losses), net	3				11			2,247				(156		)		(1,697		)	(6)	408
Net other-than-temporary impairments	—				—			(15		)		—				—				(15		)
Fair value (losses) gains, net	(3		)		—			1,716				(418		)		368			(7)	1,663
Debt extinguishment (losses) gains, net	—				—			(37		)		41				—				4
Gains from partnership investments(8)	—				163			—				—				11				174
Fee and other income (expense)	351				89			604				(170		)		74				948
Administrative expenses	(845		)		(137		)	(285		)		—				—				(1,267		)
Foreclosed property income	581				11			—				—				—				592
TCCA fees(4)	(419		)		—			—				—				—				(419		)
Other (expenses) income	(322		)		1			50				—				(39		)		(310		)
Income before federal income taxes	10,869				907			9,120				2,028				(2,730		)		20,194
Benefit for federal income taxes(11)	30,528				7,978			10,080				—				—				48,586
Net income	41,397				8,885			19,200				2,028				(2,730		)		68,780
Less: Net income attributable to noncontrolling interest	—				—			—				—				(11		)	(9)	(11		)
Net income attributable to Fannie Mae	$	41,397			$	8,885		$	19,200			$	2,028			$	(2,741	)		$	68,769
__________
(1)	Represents activity related to the assets and liabilities of consolidated trusts in our condensed consolidated balance sheets.
(2)	Represents the elimination of intercompany transactions occurring between the three business segments and our consolidated trusts, as well as other adjustments to reconcile to our consolidated results.
(3)	Represents the amortization expense of cost basis adjustments on securities in the Capital Markets group’s retained mortgage portfolio that on a GAAP basis are eliminated.
(4)	Includes the impact of a 10 basis point guaranty fee increase implemented pursuant to the TCCA, the incremental revenue from which must be remitted to Treasury. The resulting revenue is included in guaranty fee income and the expense is recognized as “TCCA fees.”
(5)	Represents the guaranty fees paid from consolidated trusts to the Single-Family and Multifamily segments. The adjustment to guaranty fee income in the Eliminations/Adjustments column represents the elimination of the amortization of deferred cash fees related to consolidated trusts that were re-established for segment reporting. Total guaranty fee income related to unconsolidated Fannie Mae MBS trusts and other credit enhancement arrangements is included in fee and other income in our condensed consolidated statements of operations and comprehensive income.
(6)	Primarily represents the removal of realized gains and losses on sales of Fannie Mae MBS classified as available-for-sale securities that are issued by consolidated trusts and in the Capital Markets group’s retained mortgage portfolio. The adjustment also includes the removal of securitization gains (losses) recognized in the Capital Markets segment relating to portfolio securitization transactions that do not qualify for sale accounting under GAAP.
(7)	Represents the removal of fair value adjustments on consolidated Fannie Mae MBS classified as trading that are in the Capital Markets group’s retained mortgage portfolio.
(8)	Gains from partnership investments are included in other expenses in our condensed consolidated statements of operations and comprehensive income.
(9)	Represents the adjustment from equity method of accounting to consolidated accounting for partnership investments that are consolidated in our consolidated balance sheets.
(10)	Certain prior period amounts have been reclassified to conform with the current period presentation.
(11)	Primarily represented the release of the valuation allowance for our deferred tax assets that generally is directly attributable to each segment based on the nature of the item.

Equity_Tables

Equity (Tables)	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Schedule of Other Comprehensive Income (Loss) [Table Text Block]	'
	The following table displays the activity in other comprehensive income (“OCI”), net of tax, by major categories for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,								For the Six Months Ended June 30,
		2014				2013				2014				2013
		(Dollars in millions)
	Net income	$	3,667			$	10,095			$	8,992			$	68,780
	Other comprehensive income, net of tax effect:
	Changes in net unrealized gains on AFS securities (net of tax of $119 and $47, respectively, for the three months ended and net of tax of $303 and $396, respectively, for the six months ended)	221				88				561				735
	Reclassification adjustment for OTTI recognized in net income (net of tax of $8 and $2, respectively, for the three months ended and net of tax of $26 and $5, respectively, for the six months ended)	15				4				48				10
	Reclassification adjustment for gains on AFS securities included in net income (net of tax of $104 and $40, respectively, for the three months ended and net of tax of $104 and $43, respectively, for the six months ended)	(191		)		(75		)		(192		)		(80		)
	Other	—				149				—				155
	Total other comprehensive income	45				166				417				820
	Total comprehensive income	$	3,712			$	10,261			$	9,409			$	69,600
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	The following table displays our accumulated other comprehensive income (“AOCI”) by major categories as of June 30, 2014 and December 31, 2013.
			As of
		June 30,						December 31,
		2014						2013
		(Dollars in millions)
	Net unrealized gains on AFS securities for which we have not recorded OTTI, net of tax		$	561					$	365
	Net unrealized gains on AFS securities for which we have recorded OTTI, net of tax		1,483						1,262
	Prior service cost and actuarial losses, net of amortization, net of tax		(395		)				(395		)
	Other losses		(29		)				(29		)
	Accumulated other comprehensive income		$	1,620					$	1,203
	The table below displays changes in accumulated other comprehensive income, net of tax, for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,																								For the Six Months Ended June 30,
		2014														2013										2014										2013
		AFS(1)						Other				Total				AFS(1)				Other(2)			Total			AFS(1)				Other			Total			AFS(1)				Other(2)			Total
			(Dollars in millions)
	Beginning balance		$	1,999				$	(424	)		$	1,575				$	1,582		$	(544	)	$	1,038			$	1,627		$	(424	)	$	1,203			$	934		$	(550	)	$	384
	OCI before reclassifications		221					—				221					88			145			233				561			—			561				735			145			880
	Amounts reclassified from OCI		(176		)			—				(176		)			(71		)	4			(67		)		(144		)	—			(144		)		(70		)	10			(60		)
	Net OCI		45					—				45					17			149			166				417			—			417				665			155			820
	Ending balance		$	2,044				$	(424	)		$	1,620				$	1,599		$	(395	)	$	1,204			$	2,044		$	(424	)	$	1,620			$	1,599		$	(395	)	$	1,204
	__________
	(1)	The amounts reclassified from AOCI represent the gain or loss recognized in earnings due to a sale of an AFS security or the recognition of a net impairment recognized in earnings, which are recorded in “Investments gains, net” and “Net other-than-temporary impairments,” respectively, in our condensed consolidated statements of operations.
	(2)	The amounts reclassified from AOCI represent activity from our defined benefit pension plans, which is recorded in “Salaries and employee benefits” in our condensed consolidated statements of operations.

Concentrations_of_Credit_Risk_

Concentrations of Credit Risk (Tables)	6 Months Ended
	Jun. 30, 2014
Risks and Uncertainties [Abstract]	'
Estimated Benefit from Mortgage Insurance [Table Text Block]	'
	The following table displays the amount by which our estimated benefit from mortgage insurance as of June 30, 2014 and December 31, 2013 reduced our total loss reserves as of those dates.
		As of
		June 30, 2014			December 31, 2013
			(Dollars in millions)
	Contractual mortgage insurance benefit		$	5,886		$	6,751
	Less: Collectibility adjustment(1)		354			431
	Estimated benefit included in total loss reserves		$	5,532		$	6,320
	__________
	(1)	Represents an adjustment that reduces the contractual benefit for our assessment of our mortgage insurer counterparties’ inability to fully pay the contractual mortgage insurance claims.

Netting_Arrangements_Tables

Netting Arrangements (Tables)	6 Months Ended
	Jun. 30, 2014
Offsetting [Abstract]	'
Offsetting [Table Text Block]	'
	The table below displays information related to derivatives and securities purchased under agreements to resell or similar arrangements which are subject to an enforceable master netting arrangement that are either offset or not offset in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013.
			As of June 30, 2014
										Net Amount Presented in the Condensed Consolidated Balance Sheets						Amounts Not Offset in the Condensed Consolidated Balance Sheets
			Gross Amount			Gross Amount Offset(1)										Financial Instruments(2)				Collateral (3)				Net Amount
			(Dollars in millions)
	Assets:
	OTC risk management derivatives		$	6,795			$	(6,777	)		$	18					$	—			$	(12	)		$	6
	OTC-cleared risk management derivatives (4)		949				(120		)		829						—				—				829
	Mortgage commitment derivatives		389				—				389						(145		)		(4		)		240
	Total derivative assets		8,133				(6,897		)		1,236			(5	)		(145		)		(16		)		1,075
	Securities purchased under agreements to resell or similar arrangements(6)		32,250				—				32,250						—				(32,249		)		1
	Total assets		$	40,383			$	(6,897	)		$	33,486					$	(145	)		$	(32,265	)		$	1,076
	Liabilities:
	OTC risk management derivatives		$	(8,352	)		$	8,142			$	(210	)				$	—			$	—			$	(210	)
	OTC-cleared risk management derivatives (4)		(1,248		)		1,248				—						—				—				—
	Mortgage commitment derivatives		(525		)		—				(525		)				145				—				(380		)
	Total liabilities		$	(10,125	)		$	9,390			$	(735	)	(5	)		$	145			$	—			$	(590	)
			As of December 31, 2013
										Net Amount Presented in the Condensed Consolidated Balance Sheets						Amounts Not Offset in the Condensed Consolidated Balance Sheets
			Gross Amount			Gross Amount Offset(1)										Financial Instruments (2)				Collateral(3)				Net Amount
			(Dollars in millions)
	Assets:
	OTC risk management derivatives		$	8,491			$	(8,422	)		$	69					$	—			$	(20	)		$	49
	Mortgage commitment derivatives		265				—				265						(83		)		—				182
	Total derivative assets		8,756				(8,422		)		334			(5	)		(83		)		(20		)		231
	Securities purchased under agreements to resell or similar arrangements(6)		50,565				—				50,565						—				(50,565		)		—
	Total assets		$	59,321			$	(8,422	)		$	50,899					$	(83	)		$	(50,585	)		$	231
	Liabilities:
	OTC risk management derivatives		$	(9,503	)		$	9,370			$	(133	)				$	—			$	—			$	(133	)
	Mortgage commitment derivatives		(214		)		—				(214		)				83				—				(131		)
	Total liabilities		$	(9,717	)		$	9,370			$	(347	)	(5	)		$	83			$	—			$	(264	)
	__________
	(1)	Represents the effect of the right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received and accrued interest.
	(2)	Mortgage commitment derivative amounts reflect where we have recognized both an asset and a liability with the same counterparty under an enforceable master netting arrangement but we have not elected to offset the related amounts in our condensed consolidated balance sheets.
	(3)	Represents collateral posted or received that has neither been recognized nor offset in our condensed consolidated balance sheets. Does not include collateral held in excess of our exposure.
	(4) As of June 30, 2014, we net OTC-cleared derivative assets and derivative liabilities where we have enforceable master netting arrangements.
	(5)	Excludes derivative assets of $28 million and $1.7 billion and derivative liabilities of $1 million and $1.1 billion recognized in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively, that are not subject to enforceable master netting arrangements.
	(6)	Includes $15.6 billion and $11.6 billion of securities purchased under agreements to resell or similar arrangements classified as “Cash and cash equivalents” in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively.

Fair_Value_Tables

Fair Value (Tables)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Recurring Changes in Fair Value [Table Text Block]	'
	The following tables display our assets and liabilities measured in our condensed consolidated balance sheets at fair value on a recurring basis subsequent to initial recognition, including instruments for which we have elected the fair value option as of June 30, 2014 and December 31, 2013.
			Fair Value Measurements as of June 30, 2014
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)						Netting Adjustment(1)						Estimated Fair Value
			(Dollars in millions)
	Recurring fair value measurements:
	Assets:
	Trading securities:
	Mortgage-related securities:
	Fannie Mae		$	—					$	5,686					$	—					$	—					$	5,686
	Freddie Mac		—						1,766						—						—						1,766
	Ginnie Mae		—						234						—						—						234
	Alt-A private-label securities		—						551						643						—						1,194
	Subprime private-label securities		—						—						1,282						—						1,282
	CMBS		—						2,641						—						—						2,641
	Mortgage revenue bonds		—						—						643						—						643
	Other		—						—						101						—						101
	Non-mortgage-related securities:
	U.S. Treasury securities		13,083						—						—						—						13,083
	Total trading securities		13,083						10,878						2,669						—						26,630
	Available-for-sale securities:
	Mortgage-related securities:
	Fannie Mae		—						6,020						2						—						6,022
	Freddie Mac		—						6,193						9						—						6,202
	Ginnie Mae		—						528						—						—						528
	Alt-A private-label securities		—						2,964						3,717						—						6,681
	Subprime private-label securities		—						—						5,705						—						5,705
	CMBS		—						1,508						—						—						1,508
	Mortgage revenue bonds		—						—						4,560						—						4,560
	Other		—						3						2,817						—						2,820
	Total available-for-sale securities		—						17,216						16,810						—						34,026
	Mortgage loans of consolidated trusts		—						12,585						2,531						—						15,116
	Other assets:
	Risk management derivatives:
	Swaps		—						7,347						86						—						7,433
	Swaptions		—						310						—						—						310
	Other		—						—						29						—						29
	Netting adjustment		—						—						—						(6,897		)				(6,897		)
	Mortgage commitment derivatives		—						365						24						—						389
	Total other assets		—						8,022						139						(6,897		)				1,264
	Total assets at fair value		$	13,083					$	48,701					$	22,149					$	(6,897	)				$	77,036
			Fair Value Measurements as of June 30, 2014
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)						Netting Adjustment(1)							Estimated Fair Value
			(Dollars in millions)
	Liabilities:
	Long-term debt:
	Of Fannie Mae:
	Senior floating		$	—					$	3,107					$	325					$	—					$	3,432
	Total of Fannie Mae		—						3,107						325						—						3,432
	Of consolidated trusts		—						15,922						498						—						16,420
	Total long-term debt		—						19,029						823						—						19,852
	Other liabilities:
	Risk management derivatives:
	Swaps		—						8,497						118						—						8,615
	Swaptions		—						985						—						—						985
	Other		—						—						1						—						1
	Netting adjustment		—						—						—						(9,390		)				(9,390		)
	Mortgage commitment derivatives		—						525						—						—						525
	Total other liabilities		—						10,007						119						(9,390		)				736
	Total liabilities at fair value		$	—					$	29,036					$	942					$	(9,390	)				$	20,588
			Fair Value Measurements as of December 31, 2013
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Netting Adjustment(1)						Estimated Fair Value
														(Level 3)
			(Dollars in millions)
Assets:
Trading securities:
Mortgage-related securities:
Fannie Mae		$	—					$	5,828					$	42					$	—					$	5,870
Freddie Mac		—						1,837						2						—						1,839
Ginnie Mae		—						407						—						—						407
Alt-A private-label securities		—						898						618						—						1,516
Subprime private-label securities		—						—						1,448						—						1,448
CMBS		—						2,718						—						—						2,718
Mortgage revenue bonds		—						—						565						—						565
Other		—						—						99						—						99
Non-mortgage-related securities:
U.S. Treasury securities		16,306						—						—						—						16,306
Total trading securities		16,306						11,688						2,774						—						30,768
Available-for-sale securities:
Mortgage-related securities:
Fannie Mae		—						6,566						7						—						6,573
Freddie Mac		—						6,834						8						—						6,842
Ginnie Mae		—						588						—						—						588
Alt-A private-label securities		—						3,558						3,791						—						7,349
Subprime private-label securities		—						—						7,068						—						7,068
CMBS		—						1,606						—						—						1,606
Mortgage revenue bonds		—						3						5,253						—						5,256
Other		—						4						2,885						—						2,889
Total available-for-sale securities		—						19,159						19,012						—						38,171
Mortgage loans of consolidated trusts		—						11,564						2,704						—						14,268
Other assets:
Risk management derivatives:
Swaps		—						9,604						36						—						9,640
Swaptions		—						561						1						—						562
Other		—						—						28						—						28
Netting adjustment		—						—						—						(8,422		)				(8,422		)
Mortgage commitment derivatives		—						265						—						—						265
Total other assets		—						10,430						65						(8,422		)				2,073
Total assets at fair value		$	16,306					$	52,841					$	24,555					$	(8,422	)				$	85,280
		Fair Value Measurements as of December 31, 2013
	Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Netting Adjustment(1)						Estimated Fair Value
													(Level 3)
		(Dollars in millions)
Liabilities:
Long-term debt:
Of Fannie Mae:
Senior fixed		$	—					$	353					$	—					$	—					$	353
Senior floating		—						—						955						—						955
Total of Fannie Mae		—						353						955						—						1,308
Of consolidated trusts		—						14,458						518						—						14,976
Total long-term debt		—						14,811						1,473						—						16,284
Other liabilities:
Risk management derivatives:
Swaps		—						9,444						96						—						9,540
Swaptions		—						1,084						—						—						1,084
Other		—						—						1						—						1
Netting adjustment		—						—						—						(9,370		)				(9,370		)
Mortgage commitment derivatives		—						206						8						—						214
Total other liabilities		—						10,734						105						(9,370		)				1,469
Total liabilities at fair value		$	—					$	25,545					$	1,578					$	(9,370	)				$	17,753
__________
(1)	Derivative contracts are reported on a gross basis by level. The netting adjustment represents the effect of the legal right to offset under legally enforceable master netting agreements to settle with the same counterparty on a net basis, including cash collateral posted and received.
Fair Value Measurements Using Significant Unobservable Inputs (Level 3) [Table Text Block]	'
	The following tables display a reconciliation of all assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2014 and 2013. The tables also display gains and losses due to changes in fair value, including both realized and unrealized gains and losses, recognized in our condensed consolidated statements of operations and comprehensive income for Level 3 assets and liabilities for the three and six months ended June 30, 2014 and 2013. When assets and liabilities are transferred between levels, we recognize the transfer as of the end of the period.
		Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
		For the Three Months Ended June 30, 2014
						Total Gains or (Losses)																																			Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2014(5)
						(Realized/Unrealized)
		Balance, March 31, 2014				Included in Net Income				Included in						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance,
										Other Comprehensive																									Level 3(4)			30-Jun-14
										Income(1)
		(Dollars in millions)
	Trading securities:
	Mortgage-related:
	Alt-A private-label securities	$	655			$	84				$	—				$	—			$	(23	)		$	—			$	(22	)		$	(67	)	$	16		$	643			$	84
	Subprime private-label securities	1,453				103					—					—				(241		)		—				(33		)		—			—			1,282				204
	Mortgage revenue bonds	601				44					—					—				—				—				(2		)		—			—			643				44
	Other	102				4					—					—				—				—				(5		)		—			—			101				4
	Total trading securities	$	2,811			$	235				$	—				$	—			$	(264	)		$	—			$	(62	)		$	(67	)	$	16		$	2,669			$	336
	Available-for-sale securities:
	Mortgage-related:
	Fannie Mae	$	5			$	—				$	—				$	—			$	—			$	—			$	(1	)		$	(4	)	$	2		$	2			$	—
	Freddie Mac	8				—					—					—				—				—				—				—			1			9				—
	Alt-A private-label securities	3,570				103					(24		)			—				(320		)		—				(111		)		(265		)	764			3,717				—
	Subprime private-label securities	7,030				268					(38		)			—				(1,349		)		—				(206		)		—			—			5,705				—
	Mortgage revenue bonds	5,006				(7		)			87					—				(39		)		—				(487		)		—			—			4,560				—
	Other	2,844				3					54					—				—				—				(84		)		—			—			2,817				—
	Total available-for-sale securities	$	18,463			$	367				$	79				$	—			$	(1,708	)		$	—			$	(889	)		$	(269	)	$	767		$	16,810			$	—
	Mortgage loans of consolidated trusts	$	2,608			$	102				$	—				$	7			$	—			$	—			$	(85	)		$	(165	)	$	64		$	2,531			$	86
	Net derivatives	(23		)		47					—					—				—				—				(4		)		—			—			20				41
	Long-term debt:
	Of Fannie Mae:
	Senior floating	$	(310	)		$	(15	)			$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(325	)		$	(15	)
	Of consolidated trusts	(506		)		(33		)			—					—				—				(1		)		17				47			(22		)	(498		)		(31		)
	Total long-term debt	$	(816	)		$	(48	)			$	—				$	—			$	—			$	(1	)		$	17			$	47		$	(22	)	$	(823	)		$	(46	)
		Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
		For the Six Months Ended June 30, 2014
						Total (Losses) or Gains (Realized/Unrealized)																																			Net Unrealized Gains (Losses) Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2014(5)
		Balance, December 31, 2013				Included in Net Income				Included in						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance,
										Other Comprehensive																									Level 3(4)			30-Jun-14
										Income(1)
		(Dollars in millions)
	Trading securities:
	Mortgage-related:
	Fannie Mae	$	42			$	(1	)			$	—				$	—			$	—			$	—			$	(2	)		$	(39	)	$	—		$	—			$	—
	Freddie Mac	2				—					—					—				—				—				—				(2		)	—			—				—
	Alt-A private-label securities	618				103					—					—				(23		)		—				(38		)		(143		)	126			643				101
	Subprime private-label securities	1,448				179					—					—				(241		)		—				(104		)		—			—			1,282				280
	Mortgage revenue bonds	565				84					—					—				—				—				(6		)		—			—			643				84
	Other	99				9					—					—				—				—				(7		)		—			—			101				9
	Total trading securities	$	2,774			$	374				$	—				$	—			$	(264	)		$	—			$	(157	)		$	(184	)	$	126		$	2,669			$	474
	Available-for-sale securities:
	Mortgage-related:
	Fannie Mae	$	7			$	—				$	—				$	—			$	—			$	—			$	(1	)		$	(6	)	$	2		$	2			$	—
	Freddie Mac	8				—					—					—				—				—				—				—			1			9				—
	Alt-A private-label securities	3,791				116					49					—				(320		)		—				(199		)		(874		)	1,154			3,717				—
	Subprime private-label securities	7,068				301					181					—				(1,349		)		—				(496		)		—			—			5,705				—
	Mortgage revenue bonds	5,253				(27		)			280					—				(58		)		—				(888		)		—			—			4,560				—
	Other	2,885				6					95					—				—				—				(169		)		—			—			2,817				—
	Total available-for-sale securities	$	19,012			$	396				$	605				$	—			$	(1,727	)		$	—			$	(1,753	)		$	(880	)	$	1,157		$	16,810			$	—
	Mortgage loans of consolidated trusts	$	2,704			$	127				$	—				$	31			$	—			$	—			$	(166	)		$	(313	)	$	148		$	2,531			$	94
	Net derivatives	(40		)		77					—					—				—				—				(16		)		(1		)	—			20				54
	Long-term debt:
	Of Fannie Mae:
	Senior floating	$	(955	)		$	(105	)			$	—				$	—			$	—			$	(750	)		$	20			$	1,465		$	—		$	(325	)		$	(59	)
	Of consolidated trusts	(518		)		(34		)			—					—				—				(1		)		35				66			(46		)	(498		)		(32		)
Total long-term debt	$	(1,473	)		$	(139	)			$	—				$	—			$	—			$	(751	)		$	55			$	1,531		$	(46	)	$	(823	)		$	(91	)
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Three Months Ended June 30, 2013
					Total (Losses) or Gains or (Realized/Unrealized)																																			Net Unrealized (Losses) Gains Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2013(5)
	Balance, March 31,				Included in Net Income				Included in Other Comprehensive Income(1)						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance, June 30, 2013
	2013																																	Level 3(4)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Fannie Mae	$	61			$	(3	)			$	—				$	—			$	—			$	—			$	(6	)		$	—		$	—		$	52			$	(3	)
Freddie Mac	2				—					—					—				—				—				—				—			—			2				—
Ginnie Mae	—				—					—					—				—				—				—				—			2			2				—
Alt-A private-label securities	464				32					—					—				—				—				(39		)		(162		)	408			703				31
Subprime private-label securities	1,446				80					—					—				—				—				(38		)		—			—			1,488				79
Mortgage revenue bonds	661				(56		)			—					—				—				—				(2		)		—			—			603				(56		)
Other	118				(6		)			—					—				—				—				(3		)		—			—			109				(6		)
Total trading securities	$	2,752			$	47				$	—				$	—			$	—			$	—			$	(88	)		$	(162	)	$	410		$	2,959			$	45
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	12			$	—				$	(1	)			$	—			$	—			$	—			$	(1	)		$	—		$	—		$	10			$	—
Freddie Mac	9				—					(1		)			—				—				—				—				—			1			9				—
Alt-A private-label securities	6,112				11					249					—				—				—				(401		)		(773		)	1,810			7,008				—
Subprime private-label securities	7,868				46					234					—				—				—				(286		)		—			—			7,862				—
Mortgage revenue bonds	7,351				12					(253		)			—				—				—				(710		)		—			—			6,400				—
Other	3,099				1					55					—				—				—				(104		)		—			—			3,051				—
Total available-for-sale securities	$	24,451			$	70				$	283				$	—			$	—			$	—			$	(1,502	)		$	(773	)	$	1,811		$	24,340			$	—
Mortgage loans of consolidated trusts	$	2,882			$	30				$	—				$	85			$	—			$	—			$	(122	)		$	(51	)	$	137		$	2,961			$	25
Net derivatives	(7		)		(89		)			—					—				—				—				31				16			—			(49		)		(44		)
Long-term debt:
Of Fannie Mae:
Senior floating	$	(383	)		$	46				$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(337	)		$	46
Of consolidated trusts	(1,077		)		(66		)			—					—				—				(5		)		56				57			(42		)	(1,077		)		(69		)
Total long-term debt	$	(1,460	)		$	(20	)			$	—				$	—			$	—			$	(5	)		$	56			$	57		$	(42	)	$	(1,414	)		$	(23	)
	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
	For the Six Months Ended June 30, 2013
					Total (Losses) or Gains or (Realized/Unrealized)																																			Net Unrealized (Losses) Gains Included in Net Income Related to Assets and Liabilities Still Held as of June 30, 2013(5)
	Balance, December 31,				Included in Net Income				Included in Other Comprehensive Income(1)						Purchases(2)				Sales(2)				Issues(3)				Settlements(3)				Transfers out of Level 3(4)			Transfers into			Balance, June 30, 2013
	2012																																	Level 3(4)
	(Dollars in millions)
Trading securities:
Mortgage-related:
Fannie Mae	$	68			$	(6	)			$	—				$	—			$	—			$	—			$	(10	)		$	—		$	—		$	52			$	(6	)
Freddie Mac	2				—					—					—				—				—				—				—			—			2				—
Ginnie Mae	1				—					—					—				—				—				(1		)		—			2			2				—
Alt-A private-label securities	104				127					—					—				—				—				(55		)		(206		)	733			703				121
Subprime private-label securities	1,319				239					—					—				—				—				(70		)		—			—			1,488				239
Mortgage revenue bonds	675				(69		)			—					—				—				—				(3		)		—			—			603				(69		)
Other	117				(4		)			—					—				—				—				(4		)		—			—			109				(4		)
Total trading securities	$	2,286			$	287				$	—				$	—			$	—			$	—			$	(143	)		$	(206	)	$	735		$	2,959			$	281
Available-for-sale securities:
Mortgage-related:
Fannie Mae	$	29			$	—				$	(1	)			$	—			$	—			$	—			$	(4	)		$	(14	)	$	—		$	10			$	—
Freddie Mac	10				—					(1		)			—				—				—				(1		)		—			1			9				—
Alt-A private-label securities	6,564				20					467					—				—				—				(669		)		(1,965		)	2,591			7,008				—
Subprime private-label securities	7,447				90					911					—				—				—				(586		)		—			—			7,862				—
Mortgage revenue bonds	7,837				10					(282		)			—				(19		)		—				(1,146		)		—			—			6,400				—
Other	3,147				5					99					—				—				—				(200		)		—			—			3,051				—
Total available-for-sale securities	$	25,034			$	125				$	1,193				$	—			$	(19	)		$	—			$	(2,606	)		$	(1,979	)	$	2,592		$	24,340			$	—
Mortgage loans of consolidated trusts	$	2,634			$	57				$	—				$	243			$	—			$	—			$	(234	)		$	(89	)	$	350		$	2,961			$	(393	)
Net derivatives	14				(129		)			—					—				—				—				54				16			(4		)	(49		)		(61		)
Long-term debt:
Of Fannie Mae:
Senior floating	$	(400	)		$	63				$	—				$	—			$	—			$	—			$	—			$	—		$	—		$	(337	)		$	63
Of consolidated trusts	(1,128		)		(120		)			—					—				—				(20		)		105				170			(84		)	(1,077		)		245
Total long-term debt	$	(1,528	)		$	(57	)			$	—				$	—			$	—			$	(20	)		$	105			$	170		$	(84	)	$	(1,414	)		$	308
__________
(1)	Gains (losses) included in other comprehensive income are included in “Changes in unrealized gains on available-for-sale securities, net of reclassification adjustments and taxes” in the condensed consolidated statements of operations and comprehensive income.
(2)	Purchases and sales include activity related to the consolidation and deconsolidation of assets of securitization trusts.
(3)	Issues and settlements include activity related to the consolidation and deconsolidation of liabilities of securitization trusts.
(4)	Transfers out of Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans and credit risk sharing securities issued under our Connecticut Avenue Securities series. Prices for these securities were obtained from multiple third-party vendors or dealers supported by market observable inputs. Transfers into Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans. Prices for these securities are based on inputs from a single source or inputs that were not readily observable.
(5)	Amount represents temporary changes in fair value. Amortization, accretion and other-than-temporary impairments are not considered unrealized and are not included in this amount.
Realized and Unrealized Gain and Losses for Level 3 Assets and Liabilities Measured on Recurring Basis [Table Text Block]	'
	The following tables display realized and unrealized gains and losses included in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013, for our Level 3 assets and liabilities measured in our condensed consolidated balance sheets at fair value on a recurring basis.
			For the Three Months Ended June 30, 2014
		Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
			(Dollars in millions)
	Total realized and unrealized gains (losses) included in net income		$	70					$	329					$	(19	)				$	323					$	703
	Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2014		$	—					$	417					$	—					$	—					$	417
			For the Six Months Ended June 30, 2014
		Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
			(Dollars in millions)
	Total realized and unrealized gains (losses) included in net income		$	140					$	435					$	(64	)				$	324					$	835
	Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2014		$	—					$	531					$	—					$	—					$	531
			For the Three Months Ended June 30, 2013
		Interest Income						Fair Value (Losses) Gains, net						Net OTTI						Other						Total
			(Dollars in millions)
	Total realized and unrealized gains (losses) included in net income		$	70					$	(31	)				$	(4	)				$	3					$	38
	Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2013		$	—					$	3					$	—					$	—					$	3
			For the Six Months Ended June 30, 2013
		Interest Income						Fair Value Gains, net						Net OTTI						Other						Total
			(Dollars in millions)
	Total realized and unrealized gains (losses) included in net income		$	125					$	161					$	(9	)				$	6					$	283
	Net unrealized gains related to Level 3 assets and liabilities still held as of June 30, 2013		$	—					$	135					$	—					$	—					$	135
Nonrecurring Changes in Fair Value [Table Text Block]	'
	The following tables display assets measured in our condensed consolidated balance sheets at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when we evaluate loans for impairment) as of June 30, 2014 and December 31, 2013.
			Fair Value Measurements as of June 30, 2014
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Estimated Fair Value
														(Level 3)
			(Dollars in millions)
	Nonrecurring fair value measurements:
	Assets:
	Mortgage loans held for sale, at lower of cost or fair value		$	—					$	89					$	151					$	240
	Single-family mortgage loans held for investment, at amortized cost:(1)
	Of Fannie Mae		—						—						17,189						17,189
	Of consolidated trusts		—						—						53						53
	Multifamily mortgage loans held for investment, at amortized cost		—						—						1,033						1,033
	Acquired property, net:
	Single-family		—						—						4,300						4,300
	Multifamily		—						—						163						163
	Other assets		—						—						113						113
	Total nonrecurring fair value measurements		$	—					$	89					$	23,002					$	23,091
			Fair Value Measurements as of December 31, 2013
		Quoted Prices in Active Markets for Identical Assets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs						Estimated Fair Value
														(Level 3)
		(Dollars in millions)
	Assets:
	Mortgage loans held for sale, at lower of cost or fair value		$	—					$	101					$	132					$	233
	Single-family mortgage loans held for investment, at amortized cost:(1)
	Of Fannie Mae		—						—						19,966						19,966
	Of consolidated trusts		—						—						79						79
	Multifamily mortgage loans held for investment, at amortized cost		—						—						1,533						1,533
	Acquired property, net:
	Single-family		—						—						4,041						4,041
	Multifamily		—						—						98						98
	Other assets		—						—						121						121
	Total nonrecurring fair value measurements		$	—					$	101					$	25,970					$	26,071
	_________
	(1)	Excludes estimated recoveries from mortgage insurance proceeds.
Valuation Techniques and Significant Unobservable Inputs for Level 3 Assets and Liabilities [Table Text Block]	'
	The following table displays valuation techniques and the range and the weighted average of significant unobservable inputs for our Level 3 assets and liabilities measured at fair value on a recurring basis as of June 30, 2014 and December 31, 2013.
			Fair Value Measurements as of June 30, 2014
			Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
			(Dollars in millions)
	Recurring fair value measurements:
	Trading securities:
	Mortgage-related securities:
	Alt-A private-label securities(3)		$	67			Consensus		Default Rate (%)		4.2					4.2
									Prepayment Speed (%)		2.2					2.2
									Severity (%)		47.1					47.1
									Spreads (bps)		240.6					240.6
			158				Consensus
			381				Discounted Cash Flow		Default Rate (%)		4.2		-	8.8		7.7
									Prepayment Speed (%)		2.2		-	5.1		3.4
									Severity (%)		47.1		-	85.3		75.5
									Spreads (bps)		247.5		-	300		266.5
			37				Other
	Total Alt-A private-label securities		643
	Subprime private-label securities(3)		198				Single Vendor
			416				Consensus		Default Rate (%)		3.7		-	11.2		7.8
									Prepayment Speed (%)		0.2		-	4.1		1.5
									Severity (%)		71.7		-	95		80.6
									Spreads (bps)		245		-	345		272.7
			549				Consensus
			119				Other
	Total subprime private-label securities		1,282
	Mortgage revenue bonds		464				Discounted Cash Flow		Spreads (bps)		103.1		-	435		322.1
			179				Other
	Total mortgage revenue bonds		643
	Other		101				Discounted Cash Flow		Spreads (bps)		445					445
	Total trading securities		$	2,669
			Fair Value Measurements as of June 30, 2014
			Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
			(Dollars in millions)
	Available-for-sale securities:
	Mortgage-related securities:
	Agency(2)		$	11			Other
	Alt-A private-label securities(3)		454				Single Vendor		Default Rate (%)		2.2		-	5.7		3.9
									Prepayment Speed (%)		1.6		-	20.7		7.1
									Severity (%)		14.2		-	95		54.6
									Spreads (bps)		156.3		-	320		239
			1,254				Consensus		Default Rate (%)		0.9		-	16.7		5.2
									Prepayment Speed (%)		0		-	36.8		10.1
									Severity (%)		27.8		-	95		69.7
									Spreads (bps)		170		-	224.6		220.1
			844				Consensus
			812				Discounted Cash Flow		Default Rate (%)		2		-	11.8		5.3
									Prepayment Speed (%)		0.6		-	8.7		6.1
									Severity (%)		24.7		-	95		51.1
									Spreads (bps)		146		-	350		242.5
			353				Other
	Total Alt-A private-label securities		3,717
	Subprime private-label securities (3)		347				Single Vendor
			2,020				Consensus		Default Rate (%)		1.8		-	20.6		6.3
									Prepayment Speed (%)		0.1		-	19.8		2.9
									Severity (%)		28		-	95		84.3
									Spreads (bps)		135		-	245		197.4
			2,846				Consensus
			492				Other
	Total subprime private-label securities		5,705
	Mortgage revenue bonds		2,155				Single Vendor		Spreads (bps)		0		-	324.6		58.2
			647				Single Vendor
			1,677				Discounted Cash Flow		Spreads (bps)		0		-	592.9		327.2
		81				Other
Total mortgage revenue bonds		4,560
Other		493				Consensus		Default Rate (%)		3.1		-	5		4.7
								Prepayment Speed (%)		2		-	9.8		3.7
								Severity (%)		0.2		-	85		71.6
								Spreads (bps)		195		-	745		336.3
		329				Consensus
		855				Discounted Cash Flow		Default Rate (%)		0		-	5		1
								Prepayment Speed (%)		0		-	8.8		1.4
								Severity (%)		0		-	85		8.4
								Spreads (bps)		220		-	445		351.4
		1,140				Other
Total Other		2,817
Total available-for-sale securities		$	16,810
		Fair Value Measurements as of June 30, 2014
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)					Weighted - Average(1)
		(Dollars in millions)
Mortgage loans of consolidated trusts:
Single-family		$	1,634			Build-Up		Default Rate (%)		0.1		-	97.6		14.7
								Prepayment Speed (%)		2.8		-	45.7		17.2
								Severity (%)		0		-	100		27.4
		237				Consensus
		408				Discounted Cash Flow		Default Rate (%)		1		-	14.6		5
								Prepayment Speed (%)		0.2		-	17.5		7.9
								Severity (%)		38.4		-	95		56.4
								Spreads (bps)		135		-	595		192.3
		72				Other
Total single-family		2,351
Multifamily		180				Build-Up		Spreads (bps)		46		-	286.4		115.2
Total mortgage loans of consolidated trusts		$	2,531
Net derivatives		$	(89	)		Internal Model
		85				Dealer Mark
		24				Other
Total net derivatives		$	20
Long-term debt:
Of Fannie Mae:
Senior floating		$	(325	)		Discounted Cash Flow
Total of Fannie Mae		(325		)
Of consolidated trusts		(216		)		Consensus
Of consolidated trusts		(139		)		Discounted Cash Flow		Default Rate (%)		1		-	10.2		3.4
								Prepayment Speed (%)		0.2		-	100		23.9
								Severity (%)		38.4		-	95		44.8
								Spreads (bps)		64		-	595		208.8
		(143		)		Other
Total of consolidated trusts		(498		)
Total long-term debt		$	(823	)
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)				Weighted - Average(1)
		(Dollars in millions)
Recurring fair value measurements:
Trading securities:
Mortgage-related securities:
Agency(2)		$	44			Other
Alt-A private-label securities(3)		60				Single Vendor		Default Rate (%)		6	-	10.8		8.7
								Prepayment Speed (%)		4.1	-	5.4		4.6
								Severity (%)		76.1	-	92.7		83.1
								Spreads (bps)		414.3	-	421.7		417.5
		325				Consensus		Default Rate (%)		6.9	-	10.4		8.9
								Prepayment Speed (%)		1.9	-	2.5		2.2
								Severity (%)		77.3	-	97.8		88.7
								Spreads (bps)		298.3	-	420.2		366.3
		85				Consensus
		148				Discounted Cash Flow		Default Rate (%)		4	-	6.9		6.5
								Prepayment Speed (%)		1.9	-	3.4		2.2
								Severity (%)		42.7	-	77.3		67.6
								Spreads (bps)		325.4	-	439.4		418.6
Total Alt-A private-label securities		618
Subprime private-label securities(3)		113				Single Vendor		Default Rate (%)		3.1	-	7.5		3.9
								Prepayment Speed (%)		1.8	-	2.5		2
								Severity (%)		75	-	87.2		75.8
								Spreads (bps)		325				325
		77				Single Vendor
		400				Consensus		Default Rate (%)		3	-	9.2		6.4
								Prepayment Speed (%)		1.4	-	2.2		1.9
								Severity (%)		50.4	-	87.2		74.4
								Spreads (bps)		325	-	425		353
		808				Consensus
		50				Discounted Cash Flow		Default Rate (%)		6.9				6.9
								Prepayment Speed (%)		0.1				0.1
								Severity (%)		75				75
								Spreads (bps)		325				325
Total subprime private-label securities		1,448
Mortgage revenue bonds		539				Discounted Cash Flow		Spreads (bps)		35	-	440		340.6
		26				Other
Total mortgage revenue bonds		565
Other		99				Discounted Cash Flow		Spreads (bps)		525				525
Total trading securities		$	2,774
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)				Weighted - Average(1)
		(Dollars in millions)
Available-for-sale securities:
Mortgage-related securities:
Agency(2)		$	15			Other
Alt-A private-label securities(3)		139				Single Vendor		Default Rate (%)		0.9	-	6.4		3.9
								Prepayment Speed (%)		9.3	-	11.9		11.3
								Severity (%)		53.7	-	82.6		68.8
								Spreads (bps)		300	-	400		349.3
		435				Single Vendor
		1,948				Consensus		Default Rate (%)		0.1	-	10.3		3.5
								Prepayment Speed (%)		0.1	-	32.9		9.9
								Severity (%)		7.2	-	100		62.3
								Spreads (bps)		210.6	-	404.2		336.7
		740				Consensus
		420				Discounted Cash Flow		Default Rate (%)		2.3	-	10.1		5.1
								Prepayment Speed (%)		1.2	-	7		3.4
								Severity (%)		45.2	-	79.5		60.5
								Spreads (bps)		220.2	-	500		381.3
		109				Other
Total Alt-A private-label securities		3,791
Subprime private-label securities(3)		442				Single Vendor		Default Rate (%)		1.8	-	11		7.4
								Prepayment Speed (%)		1	-	9.4		2
								Severity (%)		65	-	100		82.2
								Spreads (bps)		275	-	375		315.2
		322				Single Vendor
		2,981				Consensus		Default Rate (%)		0	-	36.8		7.4
								Prepayment Speed (%)		0.3	-	9.7		2.3
								Severity (%)		36.8	-	100		81.7
								Spreads (bps)		175	-	375		319.9
		2,442				Consensus
		816				Discounted Cash Flow		Default Rate (%)		0.7	-	7.6		5.1
								Prepayment Speed (%)		0.2	-	12.5		4.1
								Severity (%)		43.8	-	98		79.5
								Spreads (bps)		175	-	375		292.4
		65				Other
Total subprime private-label securities		7,068
Mortgage revenue bonds		1,937				Single Vendor		Spreads (bps)		0	-	463.2		112.1
		1,386				Single Vendor
		1,899				Discounted Cash Flow		Spreads (bps)		5.5	-	490		310
		31				Other
Total mortgage revenue bonds		5,253
Other		122				Single Vendor
		483				Consensus		Default Rate (%)		0.1	-	5		5
								Prepayment Speed (%)		3	-	11.4		3
								Severity (%)		65	-	85		84.6
								Spreads (bps)		275	-	925		526.4
		625				Consensus
		610				Discounted Cash Flow		Default Rate (%)		5				5
								Prepayment Speed (%)		10				10
								Severity (%)		55				55
								Spreads (bps)		300	-	511		469.5
		1,045				Other
Total other		2,885
Total available-for-sale securities		$	19,012
		Fair Value Measurements as of December 31, 2013
		Fair Value				Significant Valuation Techniques		Significant Unobservable Inputs(1)		Range(1)						Weighted - Average(1)
		(Dollars in millions)
Mortgage loans of consolidated trusts:
Single-family		$	1,828			Build-Up		Default Rate (%)		0.1		-	95.6			15.7
								Prepayment Speed (%)		2.3		-	37.6			14.1
								Severity (%)		0		-	100			26.6
		219				Consensus
		112				Consensus		Default Rate (%)		1.1		-	4.7			3.2
								Prepayment Speed (%)		0.2		-	16.7			15.2
								Severity (%)		63.9		-	89.5			85.6
								Spreads (bps)		175		-	950			293.9
		310				Discounted Cash Flow		Default Rate (%)		1.2		-	15.7			7
								Prepayment Speed (%)		1.9		-	16.7			7
								Severity (%)		58.8		-	97.7			75.5
								Spreads (bps)		175		-	360.6			252.1
		60				Other
Total single-family		2,529
Multifamily		175				Build-Up		Spreads (bps)		62		-	243.4			114.3
Total mortgage loans of consolidated trusts		$	2,704
Net derivatives		$	(64	)		Internal Model
		32				Dealer Mark
		(8		)		Other
Total net derivatives		$	(40	)
Long-term debt:
Of Fannie Mae:
Senior floating		$	(266	)		Discounted Cash Flow
		(689		)		Consensus		Default Rate (%)		0.2						0.2
								Prepayment Speed (%)		8.4						8.4
								Spreads (bps)		171		-	438			306.2
Total of Fannie Mae		(955		)
Of consolidated trusts		(227		)		Consensus
		(116		)		Consensus		Default Rate (%)		1.1		-	4.7			3.2
								Prepayment Speed (%)		0.2		-	16.7			15.2
								Severity (%)		63.9		-	89.5			85.6
								Spreads (bps)		175		-	950			295.1
		(80		)		Single Vendor
		(95		)		Other
Total of consolidated trusts		(518		)
Total long-term debt		$	(1,473	)
_________
(1)	Valuation techniques for which no unobservable inputs are disclosed generally reflect the use of third-party pricing services or dealers, and the range of unobservable inputs applied by these sources is not readily available or cannot be reasonably estimated. Where we have disclosed unobservable inputs for consensus and single vendor techniques, those inputs are based on our validations performed at the security level using discounted cash flows.
(2)	Includes Fannie Mae and Freddie Mac securities.
(3)	Default Rate as disclosed represents the estimated beginning annualized rate of default and is used as a basis to forecast the future default rates that serve as an input for valuation.
Level 3 Assets Measured on Nonrecurring Basis [Table Text Block]	'
	The following table displays valuation techniques for our Level 3 assets measured at fair value on a nonrecurring basis as of June 30, 2014 and December 31, 2013. The significant unobservable inputs related to these techniques primarily relate to collateral dependent valuations. The related ranges and weighted averages are not meaningful when aggregated as they vary significantly from property to property.
				Fair Value Measurements as of
		Valuation Techniques		30-Jun-14						31-Dec-13
					(Dollars in millions)
	Nonrecurring fair value measurements:
	Mortgage loans held for sale, at lower of cost or fair value	Consensus			$	112					$	132
		Build-Up			39						—
	Total mortgage loans held for sale, at lower of cost or fair value				151						132
	Single-family mortgage loans held for investment, at amortized cost:
	Of Fannie Mae	Internal Model			17,189						19,966
	Of consolidated trusts	Internal Model			53						79
	Multifamily mortgage loans held for investment, at amortized cost	Appraisals			44						39
		Broker Price Opinions			109						248
		Asset Manager Estimate			842						1,230
		Other			38						16
	Total multifamily mortgage loans held for investment, at amortized cost				1,033						1,533
	Acquired property, net:
	Single-family	Accepted Offers			854						691
		Appraisals			1,370						1,077
		Walk Forwards			1,174						1,106
		Internal Model			783						1,049
		Other			119						118
	Total single-family				4,300						4,041
	Multifamily	Accepted Offers			17						24
		Appraisals			68						65
		Broker Price Opinions			78						9
	Total multifamily				163						98
	Other assets	Appraisals			1						26
		Internal Model			104						81
		Other			8						14
	Total other assets				113						121
	Total nonrecurring assets at fair value				$	23,002					$	25,970
Fair Value of Financial Instruments [Table Text Block]	'
	The following table displays the carrying value and estimated fair value of our financial instruments as of June 30, 2014 and December 31, 2013. The fair value of financial instruments we disclose includes commitments to purchase multifamily and single-family mortgage loans, which are off-balance sheet financial instruments that we do not record in our condensed consolidated balance sheets. The fair values of these commitments are included as “Mortgage loans held for investment, net of allowance for loan losses.” The disclosure excludes certain financial instruments, such as plan obligations for pension and postretirement health care benefits, employee stock option and stock purchase plans, and also excludes all non-financial instruments. As a result, the fair value of our financial assets and liabilities does not represent the underlying fair value of our total consolidated assets and liabilities.
		As of June 30, 2014
		Carrying				Quoted Price in Active Markets for Identical Assets				Significant Other Observable Inputs				Significant Unobservable Inputs				Netting Adjustment				Estimated
		Value				(Level 1)				(Level 2)				(Level 3)								Fair Value
		(Dollars in millions)
	Financial assets:
	Cash and cash equivalents and restricted cash	$	50,434			$	34,884			$	15,550			$	—			$	—			$	50,434
	Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700				—				16,700				—				—				16,700
	Trading securities	26,630				13,083				10,878				2,669				—				26,630
	Available-for-sale securities	34,026				—				17,216				16,810				—				34,026
	Mortgage loans held for sale	625				—				169				492				—				661
	Mortgage loans held for investment, net of allowance for loan losses:
	Of Fannie Mae	247,966				—				29,361				219,051				—				248,412
	Of consolidated trusts	2,756,195				—				2,620,397				191,574				—				2,811,971
	Mortgage loans held for investment	3,004,161				—				2,649,758				410,625				—				3,060,383
	Advances to lenders	4,741				—				4,220				505				—				4,725
	Derivative assets at fair value	1,264				—				8,022				139				(6,897		)		1,264
	Guaranty assets and buy-ups	253				—				—				766				—				766
	Total financial assets	$	3,138,834			$	47,967			$	2,722,513			$	432,006			$	(6,897	)		$	3,195,589
	Financial liabilities:
	Short-term debt:
	Of Fannie Mae	$	90,926			$	—			$	90,935			$	—			$	—			$	90,935
	Of consolidated trusts	1,844				—				—				1,844				—				1,844
	Long-term debt:
	Of Fannie Mae	386,609				—				398,264				940				—				399,204
	Of consolidated trusts	2,710,166				—				2,754,120				15,054				—				2,769,174
	Derivative liabilities at fair value	736				—				10,007				119				(9,390		)		736
	Guaranty obligations	453				—				—				2,049				—				2,049
	Total financial liabilities	$	3,190,734			$	—			$	3,253,326			$	20,006			$	(9,390	)		$	3,263,942
		As of December 31, 2013
		Carrying				Quoted Price in Active Markets for Identical Assets				Significant Other Observable Inputs				Significant Unobservable Inputs				Netting Adjustment				Estimated
		Value				(Level 1)				(Level 2)				(Level 3)								Fair Value
		(Dollars in millions)
	Financial assets:
	Cash and cash equivalents and restricted cash	$	48,223			$	36,633			$	11,590			$	—			$	—			$	48,223
	Federal funds sold and securities purchased under agreements to resell or similar arrangements	38,975				—				38,975				—				—				38,975
	Trading securities	30,768				16,306				11,688				2,774				—				30,768
	Available-for-sale securities	38,171				—				19,159				19,012				—				38,171
	Mortgage loans held for sale	380				—				185				195				—				380
	Mortgage loans held for investment, net of allowance for loan losses:
	Of Fannie Mae	259,638				—				29,920				215,960				—				245,880
	Of consolidated trusts	2,766,222				—				2,569,747				176,395				—				2,746,142
	Mortgage loans held for investment	3,025,860				—				2,599,667				392,355				—				2,992,022
	Advances to lenders	3,727				—				3,165				523				—				3,688
	Derivative assets at fair value	2,073				—				10,430				65				(8,422		)		2,073
	Guaranty assets and buy-ups	267				—				—				706				—				706
	Total financial assets	$	3,188,444			$	52,939			$	2,694,859			$	415,630			$	(8,422	)		$	3,155,006
	Financial liabilities:
	Short-term debt:
	Of Fannie Mae	$	72,295			$	—			$	72,304			$	—			$	—			$	72,304
	Of consolidated trusts	2,154				—				—				2,154				—				2,154
	Long-term debt:
	Of Fannie Mae	457,139				—				463,991				1,557				—				465,548
	Of consolidated trusts	2,702,935				—				2,684,224				13,362				—				2,697,586
	Derivative liabilities at fair value	1,469				—				10,734				105				(9,370		)		1,469
	Guaranty obligations	485				—				—				2,433				—				2,433
	Total financial liabilities	$	3,236,477			$	—			$	3,231,253			$	19,611			$	(9,370	)		$	3,241,494
Fair Value Option [Table Text Block]	'
	The following table displays the fair value and unpaid principal balance of the financial instruments for which we have made fair value elections as of June 30, 2014 and December 31, 2013.
			As of
			June 30, 2014																		31-Dec-13
		Loans of Consolidated Trusts(1)						Long-Term Debt of Fannie Mae						Long-Term Debt of Consolidated Trusts(2)						Loans of Consolidated Trusts(1)						Long-Term Debt of Fannie Mae						Long-Term Debt of Consolidated Trusts(2)
			(Dollars in millions)
	Fair value		$	15,116					$	3,432					$	16,420					$	14,268					$	1,308					$	14,976
	Unpaid principal balance		14,732						3,239						15,086						14,440						1,290						13,988
	__________
	(1)	Includes nonaccrual loans with a fair value of $204 million and $196 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these nonaccrual loans as of June 30, 2014 and December 31, 2013 was $67 million and $74 million, respectively. Includes loans that are 90 days or more past due with a fair value of $276 million and $288 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these 90 or more days past due loans as of June 30, 2014 and December 31, 2013 was $64 million and $75 million, respectively.
	(2)	Includes interest-only debt instruments with no unpaid principal balance and a fair value of $74 million and $85 million as of June 30, 2014 and December 31, 2013, respectively.
	The following table displays fair value gains and losses, net, including changes attributable to instrument-specific credit risk, for loans and debt for which the fair value election was made. Amounts are recorded as a component of “Fair value (losses) gains, net” in our condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2014 and 2013.
		For the Three Months Ended June 30,
		2014																2013
		Loans				Long-Term Debt						Total (Losses) Gains						Loans				Long-Term Debt						Total Gains (Losses)
		(Dollars in millions)
	Changes in instrument-specific credit risk	$	16				$	(76	)				$	(60	)			$	66				$	2					$	68
	Other changes in fair value	371					(221		)				150					(549		)			339						(210		)
	Fair value (losses) gains, net	$	387				$	(297	)				$	90				$	(483	)			$	341					$	(142	)
		For the Six Months Ended June 30,
		2014																2013
		Loans				Long-Term Debt						Total (Losses) Gains						Loans				Long-Term Debt						Total Losses
		(Dollars in millions)
	Changes in instrument-specific credit risk	$	25				$	(127	)				$	(102	)			$	1				$	(3	)				$	(2	)
	Other changes in fair value	494					(337		)				157					(706		)			405						(301		)
	Fair value (losses) gains, net	$	519				$	(464	)				$	55				$	(705	)			$	402					$	(303	)

Summary_of_Significant_Account2

Summary of Significant Accounting Policies Narratives(Details) (USD $)	0 Months Ended	3 Months Ended				6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Related Parties [Line Items]	'	'		'		'		'		'
Number of days after which we have not been paying debts or liabilities exceed assets FHFA must place us into receivership	'	'		'		'60 days		'		'
Payments of cash dividends on senior preferred stock to Treasury	$5,700,000,000	'		'		$12,882,000,000		$63,592,000,000		'
Expected undeclared dividends payable on senior preferred stock for the next quarter	'	3,700,000,000		'		'		'		'
Deficit of core capital over statutory minimum capital requirement	140,000,000,000	140,000,000,000		'		140,000,000,000		'		137,300,000,000
Home Affordable Modification Program administrative expense reimbursements from Treasury and Freddie Mac	'	20,000,000		24,000,000		37,000,000		50,000,000		'
Income Taxes Paid	'	'		'		2,475,000,000		1,016,000,000		'
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees	'	335,000,000		233,000,000		657,000,000		419,000,000		'
Fee and other income	'	383,000,000		485,000,000		4,738,000,000		1,053,000,000		'
US Treasury [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Aggregate funding received from US Treasury pursuant to the senior preferred stock purchase agreement	116,100,000,000	116,100,000,000		'		116,100,000,000		'		'
Initial aggregate liquidation preference of senior preferred stock held by US Treasury	1,000,000,000	1,000,000,000		'		1,000,000,000		'		'
Aggregate liquidation preference of senior preferred stock	117,100,000,000	117,100,000,000		'		117,100,000,000		'		'
Total available funding from US Treasury pursuant to the senior preferred stock agreement	117,600,000,000	117,600,000,000		'		117,600,000,000		'		'
Percentage of common shares attributable to warrants issued to US Treasury as percentage to total diluted common shares	79.90%	79.90%		'		79.90%		'		'
Income Taxes Paid	'	2,100,000,000		1,000,000,000		2,500,000,000		1,000,000,000		'
Percentage of initial principal loss US Treasury will bear for Temporary Credit and Liquidity Facilities and New Issue Bond Programs	35.00%	35.00%		'		35.00%		'		'
Loss of principal or interest under Treasury's Temporary Credit and Liquidity Facility and New Issue Bond Programs	0	0		'		0		'		'
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees	'	335,000,000	[1]	233,000,000	[1],[2]	657,000,000	[1]	419,000,000	[1],[2]	'
US Treasury [Member] | Temporary Credit and Liquidity Facilities Program [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Principal and interest outstanding	494,000,000	494,000,000		'		494,000,000		'		821,000,000
US Treasury [Member] | New Issue Bond [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Principal and interest outstanding	4,400,000,000	4,400,000,000		'		4,400,000,000		'		4,500,000,000
Freddie Mac [Member] | Freddie Mac [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Fair value of mortgage-backed securities	8,000,000,000	8,000,000,000		'		8,000,000,000		'		8,700,000,000
Investment income, interest	'	73,000,000		101,000,000		151,000,000		212,000,000		'
Federal Housing Finance Agency [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
FHFA assessment fees	'	26,000,000		27,000,000		54,000,000		55,000,000		'
Single-Family [Member] | US Treasury [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees	'	335,000,000	[1]	233,000,000	[1],[2]	657,000,000	[1]	419,000,000	[1],[2]	'
Liability to Treasury Related to Increase in Single-Family Guaranty Fee Resulting from the Temporary Payroll Tax Cut Continuation Act of 2011	335,000,000	335,000,000		'		335,000,000		'		'
Temporary Payroll Tax Cut related guaranty fee paid to US Treasury	'	322,000,000		'		'		'		'
Mortgage Backed Private Label Securities and Repurchase Request Resolution Agreement [Member]	'	'		'		'		'		'
Related Parties [Line Items]	'	'		'		'		'		'
Fee and other income	'	'		'		$4,200,000,000		'		'
[1]	Includes the impact of a 10 basis point guaranty fee increase implemented pursuant to the TCCA, the incremental revenue from which must be remitted to Treasury. The resulting revenue is included in guaranty fee income and the expense is recognized as “TCCA fees.”
[2]	Certain prior period amounts have been reclassified to conform with the current period presentation.

Consolidations_and_Transfers_o2

Consolidations and Transfers of Financial Assets Unconsolidated VIEs (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts: [Abstract]	'		'
Trading, at fair value	$26,630		$30,768
Available-for-sale, at fair value	34,026		38,171
Other assets	21,400		20,231
Other liabilities	-12,957		-15,441
Consolidated VIEs [Member]	'		'
Variable Interest Entities [Line Items]	'		'
Unpaid Principal Balance Previously Unconsolidated Variable Interest Entities	381		'
Unconsolidated VIEs [Member]	'		'
Variable Interest Entities [Line Items]	'		'
Unpaid Principal Balance Previously Consolidated Variable Interest Entities	'		316
Unconsolidated VIEs [Member] | Mortgage-Backed Trusts [Member]	'		'
Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts: [Abstract]	'		'
Trading, at fair value	13,348		14,219
Available-for-sale, at fair value	30,443		33,307
Other assets	118		119
Other liabilities	-1,600		-1,668
Net carrying amount	42,309		45,977
Maximum exposure to loss	49,596	[1]	54,148	[1]
Total assets of unconsolidated mortgage-backed trusts	284,852		313,202
Unconsolidated VIEs [Member] | Limited Partnership Investments [Member]	'		'
Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts: [Abstract]	'		'
Maximum exposure to loss	20		14
Total assets of unconsolidated mortgage-backed trusts	6,300		6,800
Fannie Mae Securities [Member]	'		'
Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts: [Abstract]	'		'
Trading, at fair value	5,514		5,660
Trading, at fair value	5,686		5,870
Available-for-sale, at fair value	5,462		5,866
Non-Fannie Mae Securities [Member]	'		'
Assets and liabilities recorded in our condensed consolidated balance sheets related to mortgage-backed trusts: [Abstract]	'		'
Trading, at fair value	7,834		8,559
Available-for-sale, at fair value	$24,981		$27,441
[1]	Our maximum exposure to loss generally represents the greater of our recorded investment in the entity or the unpaid principal balance of the assets covered by our guaranty. However, our securities issued by Fannie Mae multi-class resecuritization trusts that are not consolidated do not give rise to any additional exposure to loss as we already consolidate the underlying collateral.

Consolidations_and_Transfers_o3

Consolidations and Transfers of Financial Assets Transfers of Financial Assets (Details) (USD $)

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

12 Months Ended

6 Months Ended

12 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Unconsolidated VIEs [Member]

Fannie Mae Single-class MBS & Fannie Megas [Member]

Fannie Mae Single-class MBS & Fannie Megas [Member]

REMICS & SMBS [Member]

REMICS & SMBS [Member]

Transfers of Financial Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Unpaid principal balance portfolio securitizations

$36,400,000,000

$62,500,000,000

$68,900,000,000

$131,800,000,000

'

'

'

'

'

'

'

'

Unpaid principal balance

'

'

'

'

'

'

'

'

314,000,000

349,000,000

6,664,000,000

[1]

6,899,000,000

[1]

Fair value

'

'

'

'

'

'

'

'

350,000,000

383,000,000

7,878,000,000

[1]

7,959,000,000

[1]

Weighted-average coupon

'

'

'

'

'

'

'

'

6.19%

6.21%

5.30%

[1]

5.36%

[1]

Weighted-average loan age

'

'

'

'

'

'

'

'

'7 years 11 months

'7 years 5 months

'5 years 8 months

[1]

'5 years 5 months

[1]

Weighted-average maturity

'

'

'

'

'

'

'

'

'21 years 0 months

'21 years 6 months

'11 years 1 month

[1]

'12 years 7 months

[1]

Principal and interest received on retained interests

'

'

'

'

$373,000,000

$469,000,000

$713,000,000

$928,000,000

'

'

'

'

[1]

Consists of real estate mortgage investment conduits (“REMICs”) and stripped mortgage-backed securities (“SMBS”).

Consolidations_and_Transfers_o4

Consolidations and Transfers of Financial Assets Managed Loans (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Billions, unless otherwise specified
Transfers and Servicing [Abstract]	'	'
Securitized loans in unconsolidated portfolio securitization trusts, unpaid principle balance	$2	$2.10

Consolidations_and_Transfers_o5

Consolidations and Transfers of Financial Assets Qualifying Sales of Portfolio Securitizations (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Transfers and Servicing [Abstract]	'	'	'	'
Proceeds from the initial sale of securities from portfolio securitizations	$0	$75	$0	$251

Mortgage_Loans_Loans_in_Mortga

Mortgage Loans Loans in Mortgage Portfolio (Details) (USD $)	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	$3,011,280	'	$3,039,559	'	'	'
Cost basis and fair value adjustments, net	32,573	'	30,527	'	'	'
Allowance for loan losses for loans held for investment	-39,067	-41,911	-43,846	-49,643	-56,461	-58,795
Total mortgage loans	3,004,786	'	3,026,240	'	'	'
Single-Family [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	2,829,985	'	2,855,668	'	'	'
Multifamily [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	181,295	'	183,891	'	'	'
Fannie Mae [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	298,373	'	314,286	'	'	'
Cost basis and fair value adjustments, net	-13,164	'	-13,778	'	'	'
Allowance for loan losses for loans held for investment	-36,643	-39,004	-40,521	-44,825	-49,553	-50,519
Total mortgage loans	248,566	'	259,987	'	'	'
Fannie Mae [Member] | Single-Family [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	268,114	'	276,644	'	'	'
Fannie Mae [Member] | Multifamily [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	30,259	'	37,642	'	'	'
Consolidated Trusts [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	2,712,907	'	2,725,273	'	'	'
Cost basis and fair value adjustments, net	45,737	'	44,305	'	'	'
Allowance for loan losses for loans held for investment	-2,424	-2,907	-3,325	-4,818	-6,908	-8,276
Total mortgage loans	2,756,220	'	2,766,253	'	'	'
Consolidated Trusts [Member] | Single-Family [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	2,561,871	'	2,579,024	'	'	'
Consolidated Trusts [Member] | Multifamily [Member]	'	'	'	'	'	'
Loans in Mortgage Portfolio [Line Items]	'	'	'	'	'	'
Unpaid principal balance of mortgage loans	$151,036	'	$146,249	'	'	'

Mortgage_Loans_Aging_Details

Mortgage Loans Aging (Details) (USD $)	6 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	35,149	[1]	39,184	[1]
60 - 89 days delinquent	10,378	[1]	12,138	[1]
Seriously delinquent	59,567	[1],[2]	69,706	[1],[2]
Total delinquent	105,094	[1]	121,028	[1]
Current	2,932,205	[1]	2,943,641	[1]
Total recorded investment in loans	3,037,299	[1]	3,064,669	[1]
Recorded investment in loans 90 days or more delinquent and accruing interest	414	[1]	460	[1]
Recorded investment in nonaccrual loans	70,882	[1]	83,283	[1]
Primary [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
Total recorded investment in loans	2,638,966	[1],[3],[4],[5]	2,649,297	[1],[3],[4],[5]
Government [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
Total recorded investment in loans	47,000		48,600
Alt-A [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
Total recorded investment in loans	119,532	[1],[4],[5]	127,509	[1],[4],[5]
Other [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
Total recorded investment in loans	48,852	[1],[4],[5],[6]	53,291	[1],[4],[5],[6]
Single-Family [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	35,090	[1]	39,125	[1]
60 - 89 days delinquent	10,378	[1]	12,138	[1]
Seriously delinquent	59,395	[1],[2]	69,520	[1],[2]
Total delinquent	104,863	[1]	120,783	[1]
Current	2,749,490	[1]	2,757,908	[1]
Total recorded investment in loans	2,854,353	[1]	2,878,691	[1]
Recorded investment in loans 90 days or more delinquent and accruing interest	414	[1]	460	[1]
Recorded investment in nonaccrual loans	69,265	[1]	81,074	[1]
Single-Family [Member] | Minimum [Member]	'		'
Table Footnote [Abstract]	'		'
Serious delinquency, days past due	'90 days		'90 days
Single-Family [Member] | Primary [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	29,122	[1],[3]	32,371	[1],[3]
60 - 89 days delinquent	8,323	[1],[3]	9,755	[1],[3]
Seriously delinquent	41,458	[1],[2],[3]	48,345	[1],[2],[3]
Total delinquent	78,903	[1],[3]	90,471	[1],[3]
Current	2,560,063	[1],[3]	2,558,826	[1],[3]
Total recorded investment in loans	2,638,966	[1],[3]	2,649,297	[1],[3]
Recorded investment in loans 90 days or more delinquent and accruing interest	57	[1],[3]	81	[1],[3]
Recorded investment in nonaccrual loans	49,689	[1],[3]	57,973	[1],[3]
Single-Family [Member] | Government [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	63	[1],[7]	66	[1],[7]
60 - 89 days delinquent	24	[1],[7]	32	[1],[7]
Seriously delinquent	330	[1],[2],[7]	346	[1],[2],[7]
Total delinquent	417	[1],[7]	444	[1],[7]
Current	46,586	[1],[7]	48,150	[1],[7]
Total recorded investment in loans	47,003	[1],[7]	48,594	[1],[7]
Recorded investment in loans 90 days or more delinquent and accruing interest	330	[1],[7]	346	[1],[7]
Recorded investment in nonaccrual loans	0	[1],[7]	0	[1],[7]
Single-Family [Member] | Alt-A [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	4,227	[1]	4,748	[1]
60 - 89 days delinquent	1,469	[1]	1,692	[1]
Seriously delinquent	13,220	[1],[2]	15,425	[1],[2]
Total delinquent	18,916	[1]	21,865	[1]
Current	100,616	[1]	105,644	[1]
Total recorded investment in loans	119,532	[1]	127,509	[1]
Recorded investment in loans 90 days or more delinquent and accruing interest	9	[1]	11	[1]
Recorded investment in nonaccrual loans	14,677	[1]	17,102	[1]
Single-Family [Member] | Other [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	1,678	[1],[6]	1,940	[1],[6]
60 - 89 days delinquent	562	[1],[6]	659	[1],[6]
Seriously delinquent	4,387	[1],[2],[6]	5,404	[1],[2],[6]
Total delinquent	6,627	[1],[6]	8,003	[1],[6]
Current	42,225	[1],[6]	45,288	[1],[6]
Total recorded investment in loans	48,852	[1],[6]	53,291	[1],[6]
Recorded investment in loans 90 days or more delinquent and accruing interest	18	[1],[6]	22	[1],[6]
Recorded investment in nonaccrual loans	4,899	[1],[6]	5,999	[1],[6]
Multifamily [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30 - 59 days delinquent	59	[1],[8]	59	[1],[8]
Seriously delinquent	172	[1],[2],[8]	186	[1],[2],[8]
Total delinquent	231	[1],[8]	245	[1],[8]
Current	182,715	[1],[8]	185,733	[1],[8]
Total recorded investment in loans	182,946	[1],[8],[9]	185,978	[1],[8],[9]
Recorded investment in loans 90 days or more delinquent and accruing interest	0	[1],[8]	0	[1],[8]
Recorded investment in nonaccrual loans	1,617	[1],[8]	2,209	[1],[8]
Multifamily [Member] | Minimum [Member]	'		'
Table Footnote [Abstract]	'		'
Serious delinquency, days past due	'60 days		'60 days
Multifamily [Member] | Maximum [Member]	'		'
Table Footnote [Abstract]	'		'
Serious delinquency, days past due	'89 days		'89 days
[1]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
[2]	Single-family seriously delinquent loans are loans that are 90 days or more past due or in the foreclosure process. Multifamily seriously delinquent loans are loans that are 60 days or more past due.
[3]	Consists of mortgage loans that are not included in other loan classes.
[4]	The aggregate estimated mark-to-market LTV ratio is based on the unpaid principal balance of the loan as of the end of each reported period divided by the estimated current value of the property, which we calculate using an internal valuation model that estimates periodic changes in home value.
[5]	Excludes $47.0 billion and $48.6 billion as of June 30, 2014 and December 31, 2013, respectively, of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A loans. The segment class is primarily reverse mortgages for which we do not calculate an estimated mark-to-market LTV ratio.
[6]	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
[7]	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A. Primarily consists of reverse mortgages which, due to their nature, are not aged and are included in the current column.
[8]	Multifamily loans 60-89 days delinquent are included in the seriously delinquent column.
[9]	Pass (loan is current and adequately protected by the current financial strength and debt service capacity of the borrower); special mention (loan with signs of potential weakness); substandard (loan with a well defined weakness that jeopardizes timely full repayment); and doubtful (loan with a weakness that makes collection or liquidation in full highly questionable and improbable based on existing conditions and values).

Mortgage_Loans_Narratives_Deta

Mortgage Loans Narratives (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Mortgage Loans on Real Estate [Abstract]	'	'	'	'
Carrying value of loans redesignated from HFI to HFS	$19	$74	$2,200	$74
Sale of loans, unpaid principal balance	$862	'	$1,900	'
Minimum Months Past Due of Single-Family Nonaccrual Loans	'	'	'2 months	'
Average term extension of a single-family modified loan	'162 months	'154 months	'161 months	'151 months
Average interest rate reduction of a single-family modified loan	0.99%	1.70%	1.12%	1.76%

Mortgage_Loans_Credit_Quality_

Mortgage Loans Credit Quality Indicators - SF (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	$3,037,299	[1]	$3,064,669	[1]
Primary [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,638,966	[1],[2],[3],[4]	2,649,297	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Less Than or Equal to 80% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,135,261	[1],[2],[3],[4]	2,073,079	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 80% and Less Than or Equal to 90% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	256,754	[1],[2],[3],[4]	276,011	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 90% and Less Than or Equal to 100% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	131,666	[1],[2],[3],[4]	153,474	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 100% and Less Than or Equal to 110% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	49,148	[1],[2],[3],[4]	59,630	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 110% and Less Than or Equal to 120% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	27,280	[1],[2],[3],[4]	33,954	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 120% and Less Than or Equal to 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	8,908	[1],[2],[3],[4]	11,256	[1],[2],[3],[4]
Primary [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	29,949	[1],[2],[3],[4]	41,893	[1],[2],[3],[4]
Alt-A [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	119,532	[1],[2],[3]	127,509	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Less Than or Equal to 80% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	62,455	[1],[2],[3]	61,670	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 80% and Less Than or Equal to 90% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	15,978	[1],[2],[3]	16,794	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 90% and Less Than or Equal to 100% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	13,366	[1],[2],[3]	14,709	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 100% and Less Than or Equal to 110% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	9,783	[1],[2],[3]	11,006	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 110% and Less Than or Equal to 120% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	6,651	[1],[2],[3]	7,742	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 120% and Less Than or Equal to 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,418	[1],[2],[3]	2,951	[1],[2],[3]
Alt-A [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	8,881	[1],[2],[3]	12,637	[1],[2],[3]
Other [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	48,852	[1],[2],[3],[5]	53,291	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Less Than or Equal to 80% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	24,320	[1],[2],[3],[5]	24,112	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 80% and Less Than or Equal to 90% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	6,494	[1],[2],[3],[5]	6,947	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 90% and Less Than or Equal to 100% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	5,760	[1],[2],[3],[5]	6,402	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 100% and Less Than or Equal to 110% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	4,327	[1],[2],[3],[5]	5,146	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 110% and Less Than or Equal to 120% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	3,069	[1],[2],[3],[5]	3,691	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 120% and Less Than or Equal to 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	1,054	[1],[2],[3],[5]	1,406	[1],[2],[3],[5]
Other [Member] | Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 125% [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	3,828	[1],[2],[3],[5]	5,587	[1],[2],[3],[5]
Government [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	47,000		48,600
Single-Family [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,854,353	[1]	2,878,691	[1]
Single-Family [Member] | Primary [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,638,966	[1],[4]	2,649,297	[1],[4]
Single-Family [Member] | Alt-A [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	119,532	[1]	127,509	[1]
Single-Family [Member] | Other [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	48,852	[1],[5]	53,291	[1],[5]
Single-Family [Member] | Government [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	$47,003	[1],[6]	$48,594	[1],[6]
[1]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
[2]	The aggregate estimated mark-to-market LTV ratio is based on the unpaid principal balance of the loan as of the end of each reported period divided by the estimated current value of the property, which we calculate using an internal valuation model that estimates periodic changes in home value.
[3]	Excludes $47.0 billion and $48.6 billion as of June 30, 2014 and December 31, 2013, respectively, of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A loans. The segment class is primarily reverse mortgages for which we do not calculate an estimated mark-to-market LTV ratio.
[4]	Consists of mortgage loans that are not included in other loan classes.
[5]	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.
[6]	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A. Primarily consists of reverse mortgages which, due to their nature, are not aged and are included in the current column.

Mortgage_Loans_Credit_Quality_1

Mortgage Loans Credit Quality Indicators - MF (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	$3,037,299	[1]	$3,064,669	[1]
Multifamily [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	182,946	[1],[2],[3]	185,978	[1],[2],[3]
Multifamily [Member] | Pass [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	174,656	[1],[2]	176,528	[1],[2]
Multifamily [Member] | Special Mention [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	2,523	[1],[2]	2,234	[1],[2]
Multifamily [Member] | Substandard [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	5,346	[1],[2]	6,758	[1],[2]
Multifamily [Member] | Doubtful [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Total recorded investment in loans	$421	[1],[2]	$458	[1],[2]
[1]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
[2]	Pass (loan is current and adequately protected by the current financial strength and debt service capacity of the borrower); special mention (loan with signs of potential weakness); substandard (loan with a well defined weakness that jeopardizes timely full repayment); and doubtful (loan with a weakness that makes collection or liquidation in full highly questionable and improbable based on existing conditions and values).
[3]	Multifamily loans 60-89 days delinquent are included in the seriously delinquent column.

Mortgage_Loans_Individually_Im

Mortgage Loans Individually Impaired Loans (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	$182,375		$185,695
Individually impaired loans with related allowance recorded: total recorded investment	172,401	[1]	175,619	[1]
Related allowance for loan losses	34,873	[2]	37,729	[2]
Individually impaired loans with no related allowance recorded: unpaid principal balance	21,780	[3]	20,452	[3]
Individually impaired loans with no related allowance recorded: total recorded investment	19,345	[1],[3]	17,660	[1],[3]
Total individually impaired loans: unpaid principal balance	204,155	[2]	206,147	[2]
Total individually impaired loans: total recorded investment	191,746	[1],[2]	193,279	[1],[2]
Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	589	[2]	688	[2]
Single-Family [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	180,660		183,438
Individually impaired loans with related allowance recorded: total recorded investment	170,672	[1]	173,343	[1]
Related allowance for loan losses	34,624		37,423
Individually impaired loans with no related allowance recorded: unpaid principal balance	20,167	[3]	18,525	[3]
Individually impaired loans with no related allowance recorded: total recorded investment	17,723	[1],[3]	15,721	[1],[3]
Table Footnote [Abstract]	'		'
Troubled debt restructuring recorded investment	187,100		187,600
Single-Family [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	581		678
Single-Family [Member] | Primary [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	128,363	[4]	130,080	[4]
Individually impaired loans with related allowance recorded: total recorded investment	122,031	[1],[4]	123,631	[1],[4]
Related allowance for loan losses	22,370	[4]	24,145	[4]
Individually impaired loans with no related allowance recorded: unpaid principal balance	15,531	[3],[4]	14,076	[3],[4]
Individually impaired loans with no related allowance recorded: total recorded investment	14,013	[1],[3],[4]	12,305	[1],[3],[4]
Single-Family [Member] | Primary [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	363	[4]	430	[4]
Single-Family [Member] | Government [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	279	[5]	213	[5]
Individually impaired loans with related allowance recorded: total recorded investment	283	[1],[5]	210	[1],[5]
Related allowance for loan losses	42	[5]	35	[5]
Individually impaired loans with no related allowance recorded: unpaid principal balance	61	[3],[5]	120	[3],[5]
Individually impaired loans with no related allowance recorded: total recorded investment	56	[1],[3],[5]	120	[1],[3],[5]
Single-Family [Member] | Government [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	12	[5]	5	[5]
Single-Family [Member] | Alt-A [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	36,695		37,356
Individually impaired loans with related allowance recorded: total recorded investment	33,817	[1]	34,479	[1]
Related allowance for loan losses	8,673		9,364
Individually impaired loans with no related allowance recorded: unpaid principal balance	3,476	[3]	3,290	[3]
Individually impaired loans with no related allowance recorded: total recorded investment	2,705	[1],[3]	2,428	[1],[3]
Single-Family [Member] | Alt-A [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	160		187
Single-Family [Member] | Other [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	15,323	[6]	15,789	[6]
Individually impaired loans with related allowance recorded: total recorded investment	14,541	[1],[6]	15,023	[1],[6]
Related allowance for loan losses	3,539	[6]	3,879	[6]
Individually impaired loans with no related allowance recorded: unpaid principal balance	1,099	[3],[6]	1,039	[3],[6]
Individually impaired loans with no related allowance recorded: total recorded investment	949	[1],[3],[6]	868	[1],[3],[6]
Single-Family [Member] | Other [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	46	[6]	56	[6]
Multifamily [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Individually impaired loans with related allowance recorded: unpaid principal balance	1,715		2,257
Individually impaired loans with related allowance recorded: total recorded investment	1,729	[1]	2,276	[1]
Related allowance for loan losses	249		306
Individually impaired loans with no related allowance recorded: unpaid principal balance	1,613	[3]	1,927	[3]
Individually impaired loans with no related allowance recorded: total recorded investment	1,622	[1],[3]	1,939	[1],[3]
Table Footnote [Abstract]	'		'
Troubled debt restructuring recorded investment	880		911
Multifamily [Member] | Interest Receivable [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Related allowance for loan losses	$8		$10
[1]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.
[2]	Includes single-family loans restructured in a TDR with a recorded investment of $187.1 billion and $187.6 billion as of June 30, 2014 and December 31, 2013, respectively. Includes multifamily loans restructured in a TDR with a recorded investment of $880 million and $911 million as of June 30, 2014 and December 31, 2013, respectively.
[3]	The discounted cash flows or collateral value equals or exceeds the carrying value of the loan and, as such, no valuation allowance is required.
[4]	Consists of mortgage loans that are not included in other loan classes.
[5]	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
[6]	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.

Mortgage_Loans_Individually_Im1

Mortgage Loans Individually Impaired Loans - 2 (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	$173,583,000,000		$179,683,000,000		$174,255,000,000		$179,754,000,000		'
Individually impaired loans with related allowance recorded: total interest income recognized	1,488,000,000	[1]	1,514,000,000	[1]	2,981,000,000	[1]	3,036,000,000	[1]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	152,000,000		203,000,000		331,000,000		429,000,000		'
Individually impaired loans with no related allowance recorded: average recorded investment	18,700,000,000	[2]	14,712,000,000	[2]	18,375,000,000	[2]	15,318,000,000	[2]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	283,000,000	[1],[2]	388,000,000	[1],[2]	541,000,000	[1],[2]	1,291,000,000	[1],[2]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	66,000,000	[2]	74,000,000	[2]	126,000,000	[2]	149,000,000	[2]	'
Individually impaired loans: average recorded investment	192,283,000,000	[3]	194,395,000,000	[3]	192,630,000,000	[3]	195,072,000,000	[3]	'
Individually impaired loans: interest income recognized on a cash basis	218,000,000	[3]	277,000,000	[3]	457,000,000	[3]	578,000,000	[3]	'
Table Footnote [Abstract]	'		'		'		'		'
Individually impaired loans: total interest income recognized	1,771,000,000	[1],[3]	1,902,000,000	[1],[3]	3,522,000,000	[1],[3]	4,327,000,000	[1],[3]	'
Single-Family [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	171,770,000,000		176,979,000,000		172,288,000,000		177,126,000,000		'
Individually impaired loans with related allowance recorded: total interest income recognized	1,465,000,000	[1]	1,478,000,000	[1]	2,935,000,000	[1]	2,969,000,000	[1]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	152,000,000		202,000,000		331,000,000		428,000,000		'
Individually impaired loans with no related allowance recorded: average recorded investment	17,032,000,000	[2]	13,046,000,000	[2]	16,617,000,000	[2]	13,518,000,000	[2]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	263,000,000	[1],[2]	363,000,000	[1],[2]	501,000,000	[1],[2]	1,244,000,000	[1],[2]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	66,000,000	[2]	74,000,000	[2]	126,000,000	[2]	148,000,000	[2]	'
Table Footnote [Abstract]	'		'		'		'		'
Troubled debt restructuring recorded investment	187,100,000,000		'		187,100,000,000		'		187,600,000,000
Individually impaired loans: total interest income recognized	1,700,000,000		1,800,000,000		3,400,000,000		4,200,000,000		'
Individually impaired loans: contractual interest income	1,400,000,000		1,400,000,000		2,900,000,000		2,900,000,000		'
Individually impaired loans: effective yield adjustments	285,000,000		410,000,000		560,000,000		1,300,000,000		'
Single-Family [Member] | Primary [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	122,791,000,000	[4]	125,689,000,000	[4]	123,066,000,000	[4]	125,663,000,000	[4]	'
Individually impaired loans with related allowance recorded: total interest income recognized	1,093,000,000	[1],[4]	1,093,000,000	[1],[4]	2,187,000,000	[1],[4]	2,195,000,000	[1],[4]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	121,000,000	[4]	152,000,000	[4]	261,000,000	[4]	325,000,000	[4]	'
Individually impaired loans with no related allowance recorded: average recorded investment	13,413,000,000	[2],[4]	10,301,000,000	[2],[4]	13,055,000,000	[2],[4]	10,688,000,000	[2],[4]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	205,000,000	[1],[2],[4]	283,000,000	[1],[2],[4]	390,000,000	[1],[2],[4]	924,000,000	[1],[2],[4]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	53,000,000	[2],[4]	57,000,000	[2],[4]	101,000,000	[2],[4]	116,000,000	[2],[4]	'
Single-Family [Member] | Government [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	281,000,000	[5]	214,000,000	[5]	257,000,000	[5]	211,000,000	[5]	'
Individually impaired loans with related allowance recorded: total interest income recognized	3,000,000	[1],[5]	2,000,000	[1],[5]	6,000,000	[1],[5]	5,000,000	[1],[5]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	0	[5]	0	[5]	0	[5]	0	[5]	'
Individually impaired loans with no related allowance recorded: average recorded investment	56,000,000	[2],[5]	112,000,000	[2],[5]	76,000,000	[2],[5]	110,000,000	[2],[5]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	2,000,000	[1],[2],[5]	2,000,000	[1],[2],[5]	3,000,000	[1],[2],[5]	4,000,000	[1],[2],[5]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	0	[2],[5]	0	[2],[5]	0	[2],[5]	0	[2],[5]	'
Single-Family [Member] | Alt-A [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	34,029,000,000		35,376,000,000		34,178,000,000		35,422,000,000		'
Individually impaired loans with related allowance recorded: total interest income recognized	267,000,000	[1]	275,000,000	[1]	537,000,000	[1]	552,000,000	[1]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	22,000,000		35,000,000		50,000,000		74,000,000		'
Individually impaired loans with no related allowance recorded: average recorded investment	2,636,000,000	[2]	1,972,000,000	[2]	2,576,000,000	[2]	2,049,000,000	[2]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	43,000,000	[1],[2]	55,000,000	[1],[2]	84,000,000	[1],[2]	230,000,000	[1],[2]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	10,000,000	[2]	12,000,000	[2]	20,000,000	[2]	22,000,000	[2]	'
Single-Family [Member] | Other [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	14,669,000,000	[6]	15,700,000,000	[6]	14,787,000,000	[6]	15,830,000,000	[6]	'
Individually impaired loans with related allowance recorded: total interest income recognized	102,000,000	[1],[6]	108,000,000	[1],[6]	205,000,000	[1],[6]	217,000,000	[1],[6]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	9,000,000	[6]	15,000,000	[6]	20,000,000	[6]	29,000,000	[6]	'
Individually impaired loans with no related allowance recorded: average recorded investment	927,000,000	[2],[6]	661,000,000	[2],[6]	910,000,000	[2],[6]	671,000,000	[2],[6]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	13,000,000	[1],[2],[6]	23,000,000	[1],[2],[6]	24,000,000	[1],[2],[6]	86,000,000	[1],[2],[6]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	3,000,000	[2],[6]	5,000,000	[2],[6]	5,000,000	[2],[6]	10,000,000	[2],[6]	'
Multifamily [Member]	'		'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'		'
Individually impaired loans with related allowance recorded: average recorded investment	1,813,000,000		2,704,000,000		1,967,000,000		2,628,000,000		'
Individually impaired loans with related allowance recorded: total interest income recognized	23,000,000	[1]	36,000,000	[1]	46,000,000	[1]	67,000,000	[1]	'
Individually impaired loans with related allowance recorded: interest income recognized on a cash basis	0		1,000,000		0		1,000,000		'
Individually impaired loans with no related allowance recorded: average recorded investment	1,668,000,000	[2]	1,666,000,000	[2]	1,758,000,000	[2]	1,800,000,000	[2]	'
Individually impaired loans with no related allowance recorded: total interest income recognized	20,000,000	[1],[2]	25,000,000	[1],[2]	40,000,000	[1],[2]	47,000,000	[1],[2]	'
Individually impaired loans with no related allowance recorded: interest income recognized on a cash basis	0	[2]	0	[2]	0	[2]	1,000,000	[2]	'
Table Footnote [Abstract]	'		'		'		'		'
Troubled debt restructuring recorded investment	$880,000,000		'		$880,000,000		'		$911,000,000
[1]	Total single-family interest income recognized of $1.7 billion and $1.8 billion for the three months ended June 30, 2014 and 2013, respectively, consists of $1.4 billion of contractual interest for both periods and $285 million and $410 million of effective yield adjustments, respectively. Total single-family interest income recognized of $3.4 billion and $4.2 billion for the six months ended June 30, 2014 and 2013, respectively, consists of $2.9 billion of contractual interest for both periods and $560 million and $1.3 billion of effective yield adjustments, respectively.
[2]	The discounted cash flows or collateral value equals or exceeds the carrying value of the loan and, as such, no valuation allowance is required.
[3]	Includes single-family loans restructured in a TDR with a recorded investment of $187.1 billion and $187.6 billion as of June 30, 2014 and December 31, 2013, respectively. Includes multifamily loans restructured in a TDR with a recorded investment of $880 million and $911 million as of June 30, 2014 and December 31, 2013, respectively.
[4]	Consists of mortgage loans that are not included in other loan classes.
[5]	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
[6]	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.

Mortgage_Loans_TDR_Details

Mortgage Loans TDR (Details) (USD $)	3 Months Ended				6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
	contracts		contracts		contracts		contracts
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	29,578		38,227		63,922		85,743
Recorded investment troubled debt restructurings activity	$4,374	[1]	$6,295	[1]	$9,485	[1]	$13,658	[1]
Number of loans troubled debt restructurings subsequent default	10,025		14,790		20,593		30,377
Recorded investment troubled debt restructurings subsequent default	1,596	[2]	2,419	[2]	3,297	[2]	4,974	[2]
Single-Family [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	29,575		38,210		63,913		85,718
Recorded investment troubled debt restructurings activity	4,370	[1]	6,160	[1]	9,447	[1]	13,490	[1]
Number of loans troubled debt restructurings subsequent default	10,024		14,787		20,588		30,371
Recorded investment troubled debt restructurings subsequent default	1,593	[2]	2,414	[2]	3,280	[2]	4,954	[2]
Single-Family [Member] | Primary [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	24,932	[3]	31,304	[3]	53,774	[3]	69,555	[3]
Recorded investment troubled debt restructurings activity	3,564	[1],[3]	4,833	[1],[3]	7,674	[1],[3]	10,477	[1],[3]
Number of loans troubled debt restructurings subsequent default	8,190	[3]	11,320	[3]	16,788	[3]	23,380	[3]
Recorded investment troubled debt restructurings subsequent default	1,251	[2],[3]	1,749	[2],[3]	2,561	[2],[3]	3,616	[2],[3]
Single-Family [Member] | Government [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	111	[4]	90	[4]	173	[4]	180	[4]
Recorded investment troubled debt restructurings activity	13	[1],[4]	10	[1],[4]	21	[1],[4]	21	[1],[4]
Number of loans troubled debt restructurings subsequent default	18	[4]	31	[4]	36	[4]	60	[4]
Recorded investment troubled debt restructurings subsequent default	1	[2],[4]	4	[2],[4]	3	[2],[4]	8	[2],[4]
Single-Family [Member] | Alt-A [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	3,660		5,175		8,056		12,285
Recorded investment troubled debt restructurings activity	614	[1]	947	[1]	1,354	[1]	2,170	[1]
Number of loans troubled debt restructurings subsequent default	1,396		2,584		2,840		5,256
Recorded investment troubled debt restructurings subsequent default	252	[2]	466	[2]	512	[2]	950	[2]
Single-Family [Member] | Other [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	872	[5]	1,641	[5]	1,910	[5]	3,698	[5]
Recorded investment troubled debt restructurings activity	179	[1],[5]	370	[1],[5]	398	[1],[5]	822	[1],[5]
Number of loans troubled debt restructurings subsequent default	420	[5]	852	[5]	924	[5]	1,675	[5]
Recorded investment troubled debt restructurings subsequent default	89	[2],[5]	195	[2],[5]	204	[2],[5]	380	[2],[5]
Multifamily [Member]	'		'		'		'
Financing Receivable, Modifications [Line Items]	'		'		'		'
Number of loans troubled debt restructurings activity	3		17		9		25
Recorded investment troubled debt restructurings activity	4	[1]	135	[1]	38	[1]	168	[1]
Number of loans troubled debt restructurings subsequent default	1		3		5		6
Recorded investment troubled debt restructurings subsequent default	$3	[2]	$5	[2]	$17	[2]	$20	[2]
[1]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Based on the nature of our modification programs, which do not include principal or past-due interest forgiveness, there is not a material difference between the recorded investment in our loans pre- and post- modification, therefore amounts represent recorded investment post-modification.
[2]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable. Represents our recorded investment in the loan at time of payment default.
[3]	Consists of mortgage loans that are not included in other loan classes.
[4]	Consists of mortgage loans guaranteed or insured, in whole or in part, by the U.S. government or one of its agencies that are not Alt-A.
[5]	Includes loans with higher-risk characteristics, such as interest-only loans and negative-amortizing loans, that are neither government nor Alt-A.

Allowance_for_Loan_Losses_Allo

Allowance for Loan Losses Allowance Rollforward (Details) (USD $)

3 Months Ended

6 Months Ended

In Millions, unless otherwise specified

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2013

Dec. 31, 2012

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

($1,558)

[1]

($5,449)

[1]

($2,430)

[1]

($6,433)

[1]

'

'

'

'

Charge-offs

-1,911

[2],[3]

-2,218

[2],[3]

-3,510

[2],[3]

-4,938

[2],[3]

'

'

'

'

Recoveries

458

572

849

1,844

'

'

'

'

Transfers

0

[4]

0

[4]

0

[4]

0

[4]

'

'

'

'

Other

167

[5]

277

[5]

312

[5]

375

[5]

'

'

'

'

Ending balance

39,067

49,643

39,067

49,643

41,911

43,846

56,461

58,795

Fannie Mae [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-1,296

[1]

-4,134

[1]

-2,190

[1]

-4,661

[1]

'

'

'

'

Charge-offs

-1,869

[2],[3]

-2,081

[2],[3]

-3,367

[2],[3]

-4,752

[2],[3]

'

'

'

'

Recoveries

311

466

631

1,493

'

'

'

'

Transfers

339

[4]

776

[4]

759

[4]

1,908

[4]

'

'

'

'

Other

154

[5]

245

[5]

289

[5]

318

[5]

'

'

'

'

Ending balance

36,643

44,825

36,643

44,825

39,004

40,521

49,553

50,519

Consolidated Trusts [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-262

[1]

-1,315

[1]

-240

[1]

-1,772

[1]

'

'

'

'

Charge-offs

-42

[2],[3]

-137

[2],[3]

-143

[2],[3]

-186

[2],[3]

'

'

'

'

Recoveries

147

106

218

351

'

'

'

'

Transfers

-339

[4]

-776

[4]

-759

[4]

-1,908

[4]

'

'

'

'

Other

13

[5]

32

[5]

23

[5]

57

[5]

'

'

'

'

Ending balance

2,424

4,818

2,424

4,818

2,907

3,325

6,908

8,276

Single-Family [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-1,528

[1]

-5,428

[1]

-2,372

[1]

-6,267

[1]

'

'

'

'

Charge-offs

-1,903

[3]

-2,152

[3]

-3,451

[3]

-4,871

[3]

'

'

'

'

Recoveries

458

572

849

1,844

'

'

'

'

Transfers

0

[4]

0

[4]

0

[4]

0

[4]

'

'

'

'

Other

168

[5]

277

[5]

310

[5]

377

[5]

'

'

'

'

Ending balance

38,643

48,770

38,643

48,770

41,448

43,307

55,501

57,687

Single-Family [Member] | Fannie Mae [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-1,288

[1]

-4,098

[1]

-2,170

[1]

-4,534

[1]

'

'

'

'

Charge-offs

-1,861

[3]

-2,015

[3]

-3,308

[3]

-4,685

[3]

'

'

'

'

Recoveries

311

466

631

1,493

'

'

'

'

Transfers

337

[4]

768

[4]

757

[4]

1,891

[4]

'

'

'

'

Other

155

[5]

244

[5]

288

[5]

319

[5]

'

'

'

'

Ending balance

36,400

44,332

36,400

44,332

38,746

40,202

48,967

49,848

Single-Family [Member] | Consolidated Trusts [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-240

[1]

-1,330

[1]

-202

[1]

-1,733

[1]

'

'

'

'

Charge-offs

-42

[3]

-137

[3]

-143

[3]

-186

[3]

'

'

'

'

Recoveries

147

106

218

351

'

'

'

'

Transfers

-337

[4]

-768

[4]

-757

[4]

-1,891

[4]

'

'

'

'

Other

13

[5]

33

[5]

22

[5]

58

[5]

'

'

'

'

Ending balance

2,243

4,438

2,243

4,438

2,702

3,105

6,534

7,839

Multifamily [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-30

[1]

-21

[1]

-58

[1]

-166

[1]

'

'

'

'

Charge-offs

-8

[3]

-66

[3]

-59

[3]

-67

[3]

'

'

'

'

Transfers

0

[4]

0

[4]

0

[4]

0

[4]

'

'

'

'

Other

-1

[5]

0

[5]

2

[5]

-2

[5]

'

'

'

'

Ending balance

424

873

424

873

463

539

960

1,108

Multifamily [Member] | Fannie Mae [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-8

[1]

-36

[1]

-20

[1]

-127

[1]

'

'

'

'

Charge-offs

-8

[3]

-66

[3]

-59

[3]

-67

[3]

'

'

'

'

Transfers

2

[4]

8

[4]

2

[4]

17

[4]

'

'

'

'

Other

-1

[5]

1

[5]

1

[5]

-1

[5]

'

'

'

'

Ending balance

243

493

243

493

258

319

586

671

Multifamily [Member] | Consolidated Trusts [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

(Benefit) provision for loan losses

-22

[1]

15

[1]

-38

[1]

-39

[1]

'

'

'

'

Charge-offs

0

[3]

0

[3]

0

[3]

0

[3]

'

'

'

'

Transfers

-2

[4]

-8

[4]

-2

[4]

-17

[4]

'

'

'

'

Other

0

[5]

-1

[5]

1

[5]

-1

[5]

'

'

'

'

Ending balance

181

380

181

380

205

220

374

437

Interest Receivable [Member]

'

'

'

'

'

'

'

'

Allowance for Loan Losses [Roll Forward]

'

'

'

'

'

'

'

'

Charge-offs

$75

$122

$169

$237

'

'

'

'

[1]

(Benefit) provision for loan losses is included in “Benefit for credit losses” in our condensed consolidated statements of operations and comprehensive income.

[2]

Total charge-offs include accrued interest of $75 million and $122 million for the three months ended June 30, 2014 and 2013, respectively, and $169 million and $237 million for the six months ended June 30, 2014 and 2013, respectively.

[3]

While we purchase the substantial majority of loans that are four or more months delinquent from our MBS trusts, we do not exercise this option to purchase loans during a forbearance period. Charge-offs of consolidated trusts generally represent loans that remained in our consolidated trusts at the time of default.

[4]

Includes transfers from trusts for delinquent loan purchases.

[5]

Amounts represent the net activity recorded in our allowances for accrued interest receivable and preforeclosure property taxes and insurance receivable from borrowers. The (benefit) provision for loan losses, charge-offs, recoveries and transfer activity included in this table reflect all changes for both the allowance for loan losses and the valuation allowances for accrued interest and preforeclosure property taxes and insurance receivable that relate to the mortgage loans.

Allowance_for_Loan_Losses_Allo1

Allowance for Loan Losses Allowance at Recorded Investment (Details) (USD $)	Jun. 30, 2014		Mar. 31, 2014	Dec. 31, 2013		Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses for individually impaired loans	$34,873	[1]	'	$37,729	[1]	'	'	'
Allowance for loan losses for collectively reserved loans	4,194		'	6,117		'	'	'
Allowance for loan losses	39,067		41,911	43,846		49,643	56,461	58,795
Recorded investment in individually impaired loans	191,746	[1],[2]	'	193,279	[1],[2]	'	'	'
Recorded investment in collectively reserved loans	2,845,553	[2]	'	2,871,390	[2]	'	'	'
Total recorded investment in loans	3,037,299	[2]	'	3,064,669	[2]	'	'	'
Single-Family [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses for individually impaired loans	34,624	[1]	'	37,423	[1]	'	'	'
Allowance for loan losses for collectively reserved loans	4,019		'	5,884		'	'	'
Allowance for loan losses	38,643		41,448	43,307		48,770	55,501	57,687
Recorded investment in individually impaired loans	188,395	[1],[2]	'	189,064	[1],[2]	'	'	'
Recorded investment in collectively reserved loans	2,665,958	[2]	'	2,689,627	[2]	'	'	'
Total recorded investment in loans	2,854,353	[2]	'	2,878,691	[2]	'	'	'
Multifamily [Member]	'		'	'		'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'	'		'	'	'
Allowance for loan losses for individually impaired loans	249	[1]	'	306	[1]	'	'	'
Allowance for loan losses for collectively reserved loans	175		'	233		'	'	'
Allowance for loan losses	424		463	539		873	960	1,108
Recorded investment in individually impaired loans	3,351	[1],[2]	'	4,215	[1],[2]	'	'	'
Recorded investment in collectively reserved loans	179,595	[2]	'	181,763	[2]	'	'	'
Total recorded investment in loans	$182,946	[2]	'	$185,978	[2]	'	'	'
[1]	Includes acquired credit-impaired loans.
[2]	Recorded investment consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments, and accrued interest receivable.

Allowance_for_Loan_Losses_Allo2

Allowance for Loan Losses Allowance Narrative (Details) (Interest Receivable [Member], USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fannie Mae [Member]	'	'
Allowance for Loan Losses [Line Items]	'	'
Allowance for Accrued Interest Receivable	$863	$1,100
Consolidated Trusts [Member]	'	'
Allowance for Loan Losses [Line Items]	'	'
Allowance for Accrued Interest Receivable	$81	$104

Investments_in_Securities_Trad

Investments in Securities Trading 1 (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	$26,630	$30,768
Mortgage-related securities [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	13,547	14,462
Freddie Mac [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	1,766	1,839
Ginnie Mae [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	234	407
Alt-A private-label securities [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	1,194	1,516
Subprime private-label securities [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	1,282	1,448
CMBS [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	2,641	2,718
Mortgage revenue bonds [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	643	565
Other mortgage-related securities [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	101	99
U.S. Treasury securities [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	13,083	16,306
Fannie Mae [Member]	'	'
Schedule of Investments in Trading Securities [Line Items]	'	'
Trading, at fair value	$5,686	$5,870

Investments_in_Securities_Trad1

Investments in Securities Trading 2 (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Investments, Debt and Equity Securities [Abstract]	'	'	'	'
Net trading gains (losses)	$249	($228)	$394	$168
Net trading gains (losses) recognized in the period related to securities still held at period end	$233	($273)	$353	$125

Investments_in_Securities_Avai

Investments in Securities Available-for-sale Securities 1 (Details) (USD $)	3 Months Ended				6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Investments, Debt and Equity Securities [Abstract]	'		'		'		'
Gross realized gains	$396		$173		$399		$182
Gross realized losses	0		53		2		57
Total proceeds	$1,705	[1]	$1,676	[1]	$1,740	[1]	$1,770	[1]
[1]	Excludes proceeds from the initial sale of securities from new portfolio securitizations included in “Note 2, Consolidations and Transfers of Financial Assets.”

Investments_in_Securities_Avai1

Investments in Securities Available-for-sale Securities 2 (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	$30,903	[1]	$35,690	[1]
Gross unrealized gains	3,570		3,364
Gross unrealized losses - OTTI	-187	[2]	-385	[2]
Gross unrealized losses - Other	-260	[3]	-498	[3]
Available-for-sale, at fair value	34,026		38,171
Fannie Mae [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	5,663	[1]	6,227	[1]
Gross unrealized gains	385		390
Gross unrealized losses - OTTI	0	[2]	0	[2]
Gross unrealized losses - Other	-26	[3]	-44	[3]
Available-for-sale, at fair value	6,022		6,573
Freddie Mac [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	5,735	[1]	6,365	[1]
Gross unrealized gains	467		477
Gross unrealized losses - OTTI	0	[2]	0	[2]
Gross unrealized losses - Other	0	[3]	0	[3]
Available-for-sale, at fair value	6,202		6,842
Ginnie Mae [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	461	[1]	512	[1]
Gross unrealized gains	67		76
Gross unrealized losses - OTTI	0	[2]	0	[2]
Gross unrealized losses - Other	0	[3]	0	[3]
Available-for-sale, at fair value	528		588
Alt-A private-label securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	5,479	[1]	6,240	[1]
Gross unrealized gains	1,220		1,151
Gross unrealized losses - OTTI	-18	[2]	-40	[2]
Gross unrealized losses - Other	0	[3]	-2	[3]
Available-for-sale, at fair value	6,681		7,349
Subprime private-label securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	4,688	[1]	6,232	[1]
Gross unrealized gains	1,057		991
Gross unrealized losses - OTTI	-19	[2]	-102	[2]
Gross unrealized losses - Other	-21	[3]	-53	[3]
Available-for-sale, at fair value	5,705		7,068
CMBS [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	1,427	[1]	1,526	[1]
Gross unrealized gains	81		80
Gross unrealized losses - OTTI	0	[2]	0	[2]
Gross unrealized losses - Other	0	[3]	0	[3]
Available-for-sale, at fair value	1,508		1,606
Mortgage revenue bonds [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	4,669	[1]	5,645	[1]
Gross unrealized gains	79		35
Gross unrealized losses - OTTI	-126	[2]	-228	[2]
Gross unrealized losses - Other	-62	[3]	-196	[3]
Available-for-sale, at fair value	4,560		5,256
Other mortgage-related securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized cost	2,781	[1]	2,943	[1]
Gross unrealized gains	214		164
Gross unrealized losses - OTTI	-24	[2]	-15	[2]
Gross unrealized losses - Other	-151	[3]	-203	[3]
Available-for-sale, at fair value	$2,820		$2,889
[1]	Amortized cost consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments as well as net other-than-temporary impairments (“OTTI”) recognized in our condensed consolidated statements of operations and comprehensive income.
[2]	Represents the noncredit component of other-than-temporary impairments losses recorded in “Accumulated other comprehensive income” in our condensed consolidated balance sheets, as well as cumulative changes in fair value of securities for which we previously recognized the credit component of other-than-temporary impairments.
[3]	Represents the gross unrealized losses on securities for which we have not recognized other-than-temporary impairments.

Investments_in_Securities_Avai2

Investments in Securities Available-for-sale Securities 3 (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	($11)	($223)
Less than 12 Consecutive Months, Fair Value	548	3,580
12 Consecutive Months or Longer, Gross Unrealized Losses	-436	-660
12 Consecutive Months or Longer, Fair Value	3,850	3,802
Fannie Mae [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	-4	-40
Less than 12 Consecutive Months, Fair Value	284	975
12 Consecutive Months or Longer, Gross Unrealized Losses	-22	-4
12 Consecutive Months or Longer, Fair Value	673	126
Alt-A private-label securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	-3	-12
Less than 12 Consecutive Months, Fair Value	121	490
12 Consecutive Months or Longer, Gross Unrealized Losses	-15	-30
12 Consecutive Months or Longer, Fair Value	113	308
Subprime private-label securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	-2	-24
Less than 12 Consecutive Months, Fair Value	72	448
12 Consecutive Months or Longer, Gross Unrealized Losses	-38	-131
12 Consecutive Months or Longer, Fair Value	618	1,332
Mortgage revenue bonds [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	-2	-147
Less than 12 Consecutive Months, Fair Value	66	1,662
12 Consecutive Months or Longer, Gross Unrealized Losses	-186	-277
12 Consecutive Months or Longer, Fair Value	1,396	970
Other mortgage-related securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less than 12 Consecutive Months, Gross Unrealized Losses	0	0
Less than 12 Consecutive Months, Fair Value	5	5
12 Consecutive Months or Longer, Gross Unrealized Losses	-175	-218
12 Consecutive Months or Longer, Fair Value	$1,050	$1,066

Investments_in_Securities_Othe

Investments in Securities Other-than-temporary Impairments 4 (Details) (USD $)	Jun. 30, 2014
In Millions, unless otherwise specified
Subprime private-label securities [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	$8,026
Weighted average collateral default	52.50%	[1]
Weighted average collateral severities	60.00%	[2]
Weighted average voluntary prepayment rates	2.50%	[3]
Average credit enhancement	11.40%	[4]
Alt-A Option ARM [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	1,279
Weighted average collateral default	36.70%	[1]
Weighted average collateral severities	50.30%	[2]
Weighted average voluntary prepayment rates	7.00%	[3]
Average credit enhancement	5.20%	[4]
Alt-A Fixed Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	2,141
Weighted average collateral default	17.40%	[1]
Weighted average collateral severities	53.80%	[2]
Weighted average voluntary prepayment rates	11.30%	[3]
Average credit enhancement	4.90%	[4]
Alt-A Variable Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	1,605
Weighted average collateral default	34.20%	[1]
Weighted average collateral severities	47.30%	[2]
Weighted average voluntary prepayment rates	8.10%	[3]
Average credit enhancement	5.30%	[4]
Alt-A Hybrid Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	2,952
Weighted average collateral default	21.50%	[1]
Weighted average collateral severities	43.50%	[2]
Weighted average voluntary prepayment rates	9.60%	[3]
Average credit enhancement	2.90%	[4]
2004 and Prior [Member] | Subprime private-label securities [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	117
Weighted average collateral default	26.50%	[1]
Weighted average collateral severities	55.20%	[2]
Weighted average voluntary prepayment rates	10.10%	[3]
Average credit enhancement	38.40%	[4]
2004 and Prior [Member] | Alt-A Option ARM [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	117
Weighted average collateral default	23.90%	[1]
Weighted average collateral severities	54.50%	[2]
Weighted average voluntary prepayment rates	9.70%	[3]
Average credit enhancement	4.10%	[4]
2004 and Prior [Member] | Alt-A Fixed Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	920
Weighted average collateral default	9.50%	[1]
Weighted average collateral severities	52.00%	[2]
Weighted average voluntary prepayment rates	13.40%	[3]
Average credit enhancement	10.90%	[4]
2004 and Prior [Member] | Alt-A Variable Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	133
Weighted average collateral default	20.80%	[1]
Weighted average collateral severities	40.80%	[2]
Weighted average voluntary prepayment rates	9.90%	[3]
Average credit enhancement	21.30%	[4]
2004 and Prior [Member] | Alt-A Hybrid Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	328
Weighted average collateral default	13.30%	[1]
Weighted average collateral severities	38.50%	[2]
Weighted average voluntary prepayment rates	10.20%	[3]
Average credit enhancement	9.40%	[4]
2005 [Member] | Subprime private-label securities [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	41
Weighted average collateral default	49.00%	[1]
Weighted average collateral severities	60.00%	[2]
Weighted average voluntary prepayment rates	2.90%	[3]
Average credit enhancement	47.90%	[4]
2005 [Member] | Alt-A Option ARM [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	472
Weighted average collateral default	31.90%	[1]
Weighted average collateral severities	53.50%	[2]
Weighted average voluntary prepayment rates	7.50%	[3]
Average credit enhancement	8.90%	[4]
2005 [Member] | Alt-A Fixed Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	828
Weighted average collateral default	22.90%	[1]
Weighted average collateral severities	54.00%	[2]
Weighted average voluntary prepayment rates	10.40%	[3]
Average credit enhancement	0.60%	[4]
2005 [Member] | Alt-A Variable Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	384
Weighted average collateral default	33.00%	[1]
Weighted average collateral severities	47.70%	[2]
Weighted average voluntary prepayment rates	8.50%	[3]
Average credit enhancement	12.60%	[4]
2005 [Member] | Alt-A Hybrid Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	1,348
Weighted average collateral default	26.40%	[1]
Weighted average collateral severities	44.20%	[2]
Weighted average voluntary prepayment rates	9.10%	[3]
Average credit enhancement	2.80%	[4]
2006 [Member] | Subprime private-label securities [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	7,527
Weighted average collateral default	0.00%	[1]
Weighted average collateral severities	61.40%	[2]
Weighted average voluntary prepayment rates	2.40%	[3]
Average credit enhancement	10.30%	[4]
2006 [Member] | Alt-A Option ARM [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	690
Weighted average collateral default	0.00%	[1]
Weighted average collateral severities	48.30%	[2]
Weighted average voluntary prepayment rates	6.10%	[3]
Average credit enhancement	2.90%	[4]
2006 [Member] | Alt-A Fixed Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	393
Weighted average collateral default	0.00%	[1]
Weighted average collateral severities	55.20%	[2]
Weighted average voluntary prepayment rates	8.30%	[3]
Average credit enhancement	0.10%	[4]
2006 [Member] | Alt-A Variable Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	1,088
Weighted average collateral default	0.00%	[1]
Weighted average collateral severities	47.70%	[2]
Weighted average voluntary prepayment rates	7.70%	[3]
Average credit enhancement	0.70%	[4]
2006 [Member] | Alt-A Hybrid Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	1,193
Weighted average collateral default	0.00%	[1]
Weighted average collateral severities	43.70%	[2]
Weighted average voluntary prepayment rates	10.10%	[3]
Average credit enhancement	0.00%	[4]
2007 and After [Member] | Subprime private-label securities [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	341
Weighted average collateral default	50.40%	[1]
Weighted average collateral severities	28.00%	[2]
Weighted average voluntary prepayment rates	1.40%	[3]
Average credit enhancement	20.30%	[4]
2007 and After [Member] | Alt-A Option ARM [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	0
2007 and After [Member] | Alt-A Fixed Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	0
2007 and After [Member] | Alt-A Variable Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	0
2007 and After [Member] | Alt-A Hybrid Rate [Member]	'
UPB and Modeled Attributes [Line Items]	'
Unpaid principal balance	$83
Weighted average collateral default	21.90%	[1]
Weighted average collateral severities	39.90%	[2]
Weighted average voluntary prepayment rates	9.90%	[3]
Average credit enhancement	20.40%	[4]
[1]	The expected remaining cumulative default rate of the collateral pool backing the securities, as a percentage of the current collateral unpaid principal balance, weighted by security unpaid principal balance.
[2]	The expected remaining loss given default of the collateral pool backing the securities, calculated as the ratio of remaining cumulative loss divided by cumulative defaults, weighted by security unpaid principal balance.
[3]	The average monthly voluntary prepayment rate, weighted by security unpaid principal balance.
[4]	The average percent current credit enhancement provided by subordination of other securities. Excludes excess interest projections and monoline bond insurance.

Investments_in_Securities_Othe1

Investments in Securities Other-than-temporary Impairments 3 (Details) (Available-for-sale securities [Member], USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Available-for-sale securities [Member]	'	'	'	'
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]	'	'	'	'
Balance, beginning of period	$7,096	$9,136	$7,904	$9,214
Additions for the credit component on debt securities for which OTTI was not previously recognized	0	2	1	7
Additions for the credit component on debt securities for which OTTI was previously recognized	8	4	47	8
Reductions for securities no longer in portfolio at period end	-384	-81	-437	-83
Reductions for securities which we intend to sell or it is more likely than not that we will be required to sell before recovery of amortized cost basis	-755	0	-1,453	0
Reductions for amortization resulting from changes in cash flows expected to be collected over the remaining life of the securities	-94	-97	-191	-182
Balance, end of period	$5,871	$8,964	$5,871	$8,964

Investments_in_Securities_Matu

Investments in Securities Maturity Information (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	$30,903	[1]	$35,690	[1]
Available-for-sale, at fair value	34,026		38,171
One Year or Less, Amortized Cost	26		'
One Year or Less, Fair Value	27		'
After One Year through Five Years, Amortized Cost	2,242		'
After One Year through Five Years, Fair Value	2,367		'
After Five Years through Ten Years, Amortized Cost	1,443		'
After Five Years through Ten Years, Fair Value	1,537		'
After Ten Years, Amortized Cost	27,192		'
After Ten Years, Fair Value	30,095		'
Fannie Mae [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	5,663	[1]	6,227	[1]
Available-for-sale, at fair value	6,022		6,573
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	321		'
After One Year through Five Years, Fair Value	339		'
After Five Years through Ten Years, Amortized Cost	284		'
After Five Years through Ten Years, Fair Value	307		'
After Ten Years, Amortized Cost	5,058		'
After Ten Years, Fair Value	5,376		'
Freddie Mac [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	5,735	[1]	6,365	[1]
Available-for-sale, at fair value	6,202		6,842
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	367		'
After One Year through Five Years, Fair Value	389		'
After Five Years through Ten Years, Amortized Cost	590		'
After Five Years through Ten Years, Fair Value	646		'
After Ten Years, Amortized Cost	4,778		'
After Ten Years, Fair Value	5,167		'
Ginnie Mae [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	461	[1]	512	[1]
Available-for-sale, at fair value	528		588
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	0		'
After One Year through Five Years, Fair Value	0		'
After Five Years through Ten Years, Amortized Cost	66		'
After Five Years through Ten Years, Fair Value	75		'
After Ten Years, Amortized Cost	395		'
After Ten Years, Fair Value	453		'
Alt-A private-label securities [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	5,479	[1]	6,240	[1]
Available-for-sale, at fair value	6,681		7,349
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	0		'
After One Year through Five Years, Fair Value	0		'
After Five Years through Ten Years, Amortized Cost	0		'
After Five Years through Ten Years, Fair Value	0		'
After Ten Years, Amortized Cost	5,479		'
After Ten Years, Fair Value	6,681		'
Subprime private-label securities [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	4,688	[1]	6,232	[1]
Available-for-sale, at fair value	5,705		7,068
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	0		'
After One Year through Five Years, Fair Value	0		'
After Five Years through Ten Years, Amortized Cost	0		'
After Five Years through Ten Years, Fair Value	0		'
After Ten Years, Amortized Cost	4,688		'
After Ten Years, Fair Value	5,705		'
CMBS [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	1,427	[1]	1,526	[1]
Available-for-sale, at fair value	1,508		1,606
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	1,345		'
After One Year through Five Years, Fair Value	1,424		'
After Five Years through Ten Years, Amortized Cost	0		'
After Five Years through Ten Years, Fair Value	0		'
After Ten Years, Amortized Cost	82		'
After Ten Years, Fair Value	84		'
Mortgage revenue bonds [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	4,669	[1]	5,645	[1]
Available-for-sale, at fair value	4,560		5,256
One Year or Less, Amortized Cost	26		'
One Year or Less, Fair Value	27		'
After One Year through Five Years, Amortized Cost	209		'
After One Year through Five Years, Fair Value	212		'
After Five Years through Ten Years, Amortized Cost	467		'
After Five Years through Ten Years, Fair Value	470		'
After Ten Years, Amortized Cost	3,967		'
After Ten Years, Fair Value	3,851		'
Other mortgage-related securities [Member]	'		'
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'		'
Amortized cost	2,781	[1]	2,943	[1]
Available-for-sale, at fair value	2,820		2,889
One Year or Less, Amortized Cost	0		'
One Year or Less, Fair Value	0		'
After One Year through Five Years, Amortized Cost	0		'
After One Year through Five Years, Fair Value	3		'
After Five Years through Ten Years, Amortized Cost	36		'
After Five Years through Ten Years, Fair Value	39		'
After Ten Years, Amortized Cost	2,745		'
After Ten Years, Fair Value	$2,778		'
[1]	Amortized cost consists of unpaid principal balance, unamortized premiums, discounts and other cost basis adjustments as well as net other-than-temporary impairments (“OTTI”) recognized in our condensed consolidated statements of operations and comprehensive income.

Financial_Guarantees_Narrative

Financial Guarantees (Narratives) (Details) (USD $)	6 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Guarantor Obligations [Line Items]	'		'
Maximum Exposure	47,208	[1]	49,915	[1]
Fair value of guaranty obligation associated with Fannie Mae MBS	931		1,100
Minimum [Member]	'		'
Guarantor Obligations [Line Items]	'		'
Contractual terms of our guarantees	'30 days		'30 days
Maximum [Member]	'		'
Guarantor Obligations [Line Items]	'		'
Contractual terms of our guarantees	'40 years		'40 years
Current Debt Service Coverage Ratio, Higher Risk Loans	1		1
Single-Family [Member] | Minimum [Member]	'		'
Guarantor Obligations [Line Items]	'		'
Serious delinquency, days past due	'90 days		'90 days
Multifamily [Member] | Minimum [Member]	'		'
Guarantor Obligations [Line Items]	'		'
Serious delinquency, days past due	'60 days		'60 days
Multifamily [Member] | Maximum [Member]	'		'
Guarantor Obligations [Line Items]	'		'
Serious delinquency, days past due	'89 days		'89 days
[1]	Primarily consists of the unpaid principal balance of the underlying mortgage loans.

Financial_Guarantees_Financial

Financial Guarantees Financial Guarantees and Maximum Recovery (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Financial Guarantees and Maximum Recovery [Line Items]	'		'
Maximum Exposure	$47,208	[1]	$49,915	[1]
Guaranty Obligation	453		485
Maximum Recovery	14,901	[2]	15,066	[2]
Non-consolidated Fannie Mae MBS [Member] | Unconsolidated VIEs [Member]	'		'
Financial Guarantees and Maximum Recovery [Line Items]	'		'
Maximum Exposure	18,257	[1]	19,317	[1]
Guaranty Obligation	222		232
Maximum Recovery	10,332	[2]	10,541	[2]
Other guaranty arrangements [Member] | Unconsolidated VIEs [Member]	'		'
Financial Guarantees and Maximum Recovery [Line Items]	'		'
Maximum Exposure	28,951	[1],[3]	30,598	[1],[3]
Guaranty Obligation	231	[3]	253	[3]
Maximum Recovery	$4,569	[2],[3]	$4,525	[2],[3]
[1]	Primarily consists of the unpaid principal balance of the underlying mortgage loans.
[2]	Recoverability of such credit enhancements and recourse is subject to, among other factors, our mortgage insurers’ and financial guarantors’ ability to meet their obligations to us. For information on our mortgage insurers, see “Note 14, Concentrations of Credit Risk.”
[3]	Primarily consists of credit enhancements, long-term standby commitments, and our commitment under the TCLF program.

Financial_Guarantees_Delinquen

Financial Guarantees Delinquency Status - Single-Family (Details) (Single-Family [Member])	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Minimum [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'90 days		'90 days
Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
30 days delinquent, percentage (unpaid principal balance)	1.27%	[1],[2]	1.41%	[1],[2]
60 days delinquent, percentage (unpaid principal balance)	0.38%	[1],[2]	0.44%	[1],[2]
Seriously delinquent, percentage (unpaid principal balance)	2.18%	[1],[2],[3]	2.54%	[1],[2],[3]
30 days delinquent, percentage (loan count)	1.46%	[1],[4]	1.64%	[1],[4]
60 days delinquent, percentage (loan count)	0.42%	[1],[4]	0.49%	[1],[4]
Seriously delinquent, percentage (loan count)	2.05%	[1],[3],[4]	2.38%	[1],[3],[4]
Percentage of loans with detailed loan level information	99.00%		99.00%
[1]	Consists of the portion of our single-family conventional guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total single-family conventional guaranty book of business as of June 30, 2014 and December 31, 2013.
[2]	Calculated based on the aggregate unpaid principal balance of single-family conventional loans for each category divided by the aggregate unpaid principal balance of loans in our single-family conventional guaranty book of business.
[3]	Consists of single-family conventional loans that were 90 days or more past due or in the foreclosure process as of June 30, 2014 and December 31, 2013.
[4]	Calculated based on the number of single-family conventional loans that were delinquent divided by the total number of loans in our single-family conventional guaranty book of business.

Financial_Guarantees_Risk_Char

Financial Guarantees Risk Characteristics - Single-Family (Details) (Single-Family [Member])	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of loans with detailed loan level information	99.00%		99.00%
Seriously delinquent, percentage (loan count)	2.05%	[1],[2],[3]	2.38%	[1],[2],[3]
2005 [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	3.00%	[1],[4]	4.00%	[1],[4]
Seriously delinquent, percentage (loan count)	6.47%	[1],[3],[5]	7.26%	[1],[3],[5]
2006 [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	3.00%	[1],[4]	3.00%	[1],[4]
Seriously delinquent, percentage (loan count)	10.11%	[1],[3],[5]	11.26%	[1],[3],[5]
2007 [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	4.00%	[1],[4]	5.00%	[1],[4]
Seriously delinquent, percentage (loan count)	11.08%	[1],[3],[5]	12.18%	[1],[3],[5]
2008 [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	3.00%	[1],[4]	3.00%	[1],[4]
Seriously delinquent, percentage (loan count)	6.27%	[1],[3],[5]	6.69%	[1],[3],[5]
All Other Vintages [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	87.00%	[1],[4]	85.00%	[1],[4]
Seriously delinquent, percentage (loan count)	0.91%	[1],[3],[5]	1.02%	[1],[3],[5]
Alt-A [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	4.00%	[1],[4]	5.00%	[1],[4]
Seriously delinquent, percentage (loan count)	8.37%	[1],[3],[5]	9.23%	[1],[3],[5]
Subprime [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Seriously delinquent, percentage (loan count)	15.65%	[1],[3],[5]	16.93%	[1],[3],[5]
California | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	20.00%	[1],[4]	20.00%	[1],[4]
Seriously delinquent, percentage (loan count)	0.77%	[1],[3],[5]	0.98%	[1],[3],[5]
Florida | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	6.00%	[1],[4]	6.00%	[1],[4]
Seriously delinquent, percentage (loan count)	5.46%	[1],[3],[5]	6.89%	[1],[3],[5]
Illinois | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	4.00%	[1],[4]	4.00%	[1],[4]
Seriously delinquent, percentage (loan count)	2.60%	[1],[3],[5]	3.12%	[1],[3],[5]
New Jersey | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	4.00%	[1],[4]	4.00%	[1],[4]
Seriously delinquent, percentage (loan count)	5.94%	[1],[3],[5]	6.25%	[1],[3],[5]
New York | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	5.00%	[1],[4]	5.00%	[1],[4]
Seriously delinquent, percentage (loan count)	4.24%	[1],[3],[5]	4.42%	[1],[3],[5]
All Other States [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	61.00%	[1],[4]	61.00%	[1],[4]
Seriously delinquent, percentage (loan count)	1.60%	[1],[3],[5]	1.85%	[1],[3],[5]
Original LTV Ratio Greater Than Ninety Percent and FICO Score Less Than Six Hundred Twenty [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	1.00%	[1],[4]	1.00%	[1],[4]
Seriously delinquent, percentage (loan count)	9.34%	[1],[3],[5]	10.90%	[1],[3],[5]
Estimated Mark-to-Market Loan-to-Value Ratio Greater Than 100% [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	6.00%	[1],[4]	7.00%	[1],[4]
Seriously delinquent, percentage (loan count)	11.40%	[1],[3],[5]	12.22%	[1],[3],[5]
Maximum [Member] | Subprime [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	0.50%	[1],[4],[6]	0.50%	[1],[4],[6]
Minimum [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'90 days		'90 days
[1]	Consists of the portion of our single-family conventional guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total single-family conventional guaranty book of business as of June 30, 2014 and December 31, 2013.
[2]	Calculated based on the number of single-family conventional loans that were delinquent divided by the total number of loans in our single-family conventional guaranty book of business.
[3]	Consists of single-family conventional loans that were 90 days or more past due or in the foreclosure process as of June 30, 2014 and December 31, 2013.
[4]	Calculated based on the aggregate unpaid principal balance of single-family conventional loans for each category divided by the aggregate unpaid principal balance of loans in our single-family conventional guaranty book of business.
[5]	Calculated based on the number of single-family conventional loans that were seriously delinquent divided by the total number of single-family conventional loans for each category included in our guaranty book of business.
[6]	Represents less than 0.5% of the single-family conventional guaranty book of business.

Financial_Guarantees_Delinquen1

Financial Guarantees Delinquency Status - Multifamily (Details) (Multifamily [Member])	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Guaranty Book of Business [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
30 days delinquent, percentage (unpaid principal balance)	0.03%	[1],[2]	0.03%	[1],[2]
Seriously delinquent, percentage (unpaid principal balance)	0.10%	[1],[2],[3]	0.10%	[1],[2],[3]
Percentage of loans with detailed loan level information	99.00%		99.00%
Minimum [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'60 days		'60 days
[1]	Calculated based on the aggregate unpaid principal balance of multifamily loans for each category divided by the aggregate unpaid principal balance of loans in our multifamily guaranty book of business.
[2]	Consists of the portion of our multifamily guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013 excluding loans that have been defeased.
[3]	Consists of multifamily loans that were 60 days or more past due as of the dates indicated.

Financial_Guarantees_Risk_Char1

Financial Guarantees Risk Characteristics - Multifamily (Details)	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Single-Family [Member] | Guaranty Book of Business [Member] | Conventional Loan [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of loans with detailed loan level information	99.00%		99.00%
Multifamily [Member] | Guaranty Book of Business [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of loans with detailed loan level information	99.00%		99.00%
Multifamily [Member] | Guaranty Book of Business [Member] | Current Debt Service Coverage Ratio Less Than 1.0 [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	3.00%	[1],[2],[3]	4.00%	[1],[2],[3]
Loans seriously delinquent, percentage by unpaid principal balance	0.95%	[2],[3],[4],[5]	1.09%	[2],[3],[4],[5]
Multifamily [Member] | Guaranty Book of Business [Member] | Original Loan to Value Ratio Greater Than 80% [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	3.00%	[1],[2]	3.00%	[1],[2]
Loans seriously delinquent, percentage by unpaid principal balance	0.17%	[2],[4],[5]	0.23%	[2],[4],[5]
Multifamily [Member] | Guaranty Book of Business [Member] | Original Loan to Value Ratio Less Than or Equal to 80% [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Percentage of book of business	97.00%	[1],[2]	97.00%	[1],[2]
Loans seriously delinquent, percentage by unpaid principal balance	0.10%	[2],[4],[5]	0.10%	[2],[4],[5]
Minimum [Member] | Single-Family [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'90 days		'90 days
Minimum [Member] | Multifamily [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'60 days		'60 days
Current Debt service coverage ratio reporting lag	'3 months		'3 months
Maximum [Member] | Multifamily [Member]	'		'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'		'
Serious delinquency, days past due	'89 days		'89 days
Current Debt service coverage ratio reporting lag	'6 months		'6 months
[1]	Calculated based on the aggregate unpaid principal balance of multifamily loans for each category divided by the aggregate unpaid principal balance of loans in our multifamily guaranty book of business.
[2]	Consists of the portion of our multifamily guaranty book of business for which we have detailed loan level information, which constituted approximately 99% of our total multifamily guaranty book of business as of June 30, 2014 and December 31, 2013 excluding loans that have been defeased.
[3]	Our estimates of current DSCRs are based on the latest available income information for these properties. Although we use the most recently available results of our multifamily borrowers, there is a lag in reporting, which typically can range from 3 to 6 months but in some cases may be longer.
[4]	Calculated based on the unpaid principal balance of multifamily loans that were seriously delinquent divided by the aggregate unpaid principal balance of multifamily loans for each category included in our guaranty book of business.
[5]	Consists of multifamily loans that were 60 days or more past due as of the dates indicated.

Acquired_Property_Net_Acquired1

Acquired Property Net Acquired Property Net (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Acquired Property [Roll Forward]	'	'	'	'	'
Acquired Property, Beginning Balance	$12,744	$10,719	$12,307	$11,158	'
Acquired Property, Additions	3,425	4,195	7,197	7,969	'
Acquired Property, Disposals	-3,873	-4,108	-7,208	-8,321	'
Acquired Property, Ending Balance	12,296	10,806	12,296	10,806	'
Real Estate Owned Valuation Allowance [Roll Forward]	'	'	'	'	'
Valuation Allowance, Beginning Balance	-784	-570	-686	-669	'
Valuation Allowance, Period (Increase) Decrease	48	30	-50	129	'
Valuation Allowance, Ending Balance	-736	-540	-736	-540	'
Acquired property, net	$11,560	$10,266	$11,560	$10,266	$11,621

ShortTerm_Borrowings_and_LongT2

Short-Term Borrowings and Long-Term Debt Short-term Debt (Details) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Short-term Borrowings [Line Items]	'		'
Short-term debt, outstanding	92,770,000,000		74,449,000,000
Short-term debt, Weighted-average Interest Rate	0.10%	[1]	0.13%	[1]
Secured Uncommitted Line of Credit [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Line of credit maximum borrowing capacity	20,000,000,000		20,000,000,000
Line of credit amount outstanding	0		0
Fannie Mae [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt, outstanding	90,926,000,000		72,295,000,000
Short-term debt, Weighted-average Interest Rate	0.10%	[1]	0.13%	[1]
Fannie Mae [Member] | Fixed-Rate Discount Notes [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt, outstanding	90,926,000,000	[2]	71,933,000,000	[2]
Short-term debt, Weighted-average Interest Rate	0.10%	[1],[2]	0.12%	[1],[2]
Fannie Mae [Member] | Fixed-Rate Foreign Exchange Discount Notes [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt, outstanding	0	[3]	362,000,000	[3]
Short-term debt, Weighted-average Interest Rate	0.00%	[1],[3]	1.07%	[1],[3]
Consolidated Trusts [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt, outstanding	1,844,000,000		2,154,000,000
Short-term debt, Weighted-average Interest Rate	0.10%	[1]	0.09%	[1]
Minimum [Member] | Fannie Mae [Member] | Fixed-Rate Foreign Exchange Discount Notes [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt instrument maturity	'5 days		'5 days
Maximum [Member] | Fannie Mae [Member] | Fixed-Rate Discount Notes [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt instrument maturity	'360 days		'360 days
Maximum [Member] | Fannie Mae [Member] | Fixed-Rate Foreign Exchange Discount Notes [Member]	'		'
Short-term Borrowings [Line Items]	'		'
Short-term debt instrument maturity	'360 days		'360 days
[1]	Includes the effects of discounts, premiums and other cost basis adjustments.
[2]	Represents unsecured general obligations with maturities ranging from overnight to 360 days from the date of issuance.
[3]	Represents foreign exchange discount notes issued in the Euro commercial paper market with maturities ranging from 5 to 360 days which enable investors to hold short-term investments in different currencies. We do not incur foreign exchange risk on these transactions, as we simultaneously enter into foreign currency swaps that have the effect of converting debt that we issue in foreign denominated currencies into U.S. dollars.

ShortTerm_Borrowings_and_LongT3

Short-Term Borrowings and Long-Term Debt Long-term Debt (Details) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	3,096,775,000,000		3,160,074,000,000
Long-term debt, weighted-average interest rate	3.05%	[1]	3.10%	[1]
Fannie Mae [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	386,609,000,000	[2]	457,139,000,000	[2]
Long-term debt, weighted-average interest rate	2.21%	[1],[2]	2.14%	[1],[2]
Unamortized discount, fair value adjustments and other cost basis adjustments	4,100,000,000		4,800,000,000
Fannie Mae [Member] | Senior Fixed [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	347,780,000,000		412,805,000,000
Long-term debt, weighted-average interest rate	2.31%	[1]	2.24%	[1]
Fannie Mae [Member] | Senior Fixed Benchmark Notes and Bonds [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	186,556,000,000		212,234,000,000
Long-term debt, weighted-average interest rate	2.40%	[1]	2.45%	[1]
Fannie Mae [Member] | Senior Fixed Medium-Term Notes [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	124,483,000,000	[3]	161,445,000,000	[3]
Long-term debt, weighted-average interest rate	1.36%	[1],[3]	1.28%	[1],[3]
Fannie Mae [Member] | Senior Fixed Foreign Exchange Notes and Bonds [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	680,000,000		682,000,000
Long-term debt, weighted-average interest rate	5.25%	[1]	5.41%	[1]
Fannie Mae [Member] | Senior Fixed Other Debt [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	36,061,000,000	[4]	38,444,000,000	[4]
Long-term debt, weighted-average interest rate	5.02%	[1],[4]	4.99%	[1],[4]
Fannie Mae [Member] | Senior Floating [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	34,925,000,000		39,396,000,000
Long-term debt, weighted-average interest rate	0.46%	[1]	0.32%	[1]
Fannie Mae [Member] | Senior Floating Medium-Term Notes [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	31,493,000,000	[3]	38,441,000,000	[3]
Long-term debt, weighted-average interest rate	0.18%	[1],[3]	0.20%	[1],[3]
Fannie Mae [Member] | Senior Floating Other Debt [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	3,432,000,000	[4],[5]	955,000,000	[4],[5]
Long-term debt, weighted-average interest rate	3.18%	[1],[4],[5]	5.18%	[1],[4],[5]
Fannie Mae [Member] | Subordinated Fixed [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	3,674,000,000		4,676,000,000
Long-term debt, weighted-average interest rate	9.92%	[1]	8.76%	[1]
Fannie Mae [Member] | Subordinated Fixed Qualifying Subordinated [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	0		1,169,000,000
Long-term debt, weighted-average interest rate	0.00%	[1]	5.27%	[1]
Fannie Mae [Member] | Subordinated Fixed Subordinated Debentures [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	3,674,000,000		3,507,000,000
Long-term debt, weighted-average interest rate	9.92%	[1]	9.92%	[1]
Fannie Mae [Member] | Secured Borrowings [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	230,000,000	[6]	262,000,000	[6]
Long-term debt, weighted-average interest rate	1.88%	[1],[6]	1.86%	[1],[6]
Consolidated Trusts [Member]	'		'
Long-Term Debt [Line Items]	'		'
Long-term debt, outstanding	2,710,166,000,000	[4]	2,702,935,000,000	[4]
Long-term debt, weighted-average interest rate	3.17%	[1],[4]	3.26%	[1],[4]
Minimum [Member] | Fannie Mae [Member]	'		'
Long-Term Debt [Line Items]	'		'
Medium-term Notes Original Contractual Maturity	'1 year		'1 year
Maximum [Member] | Fannie Mae [Member]	'		'
Long-Term Debt [Line Items]	'		'
Medium-term Notes Original Contractual Maturity	'10 years		'10 years
[1]	Includes the effects of discounts, premiums and other cost basis adjustments.
[2]	Reported amounts include unamortized discounts and premiums, other cost basis adjustments and fair value adjustments of $4.1 billion and $4.8 billion as of June 30, 2014 and December 31, 2013, respectively.
[3]	Includes long-term debt with an original contractual maturity of greater than 1 year and up to 10 years, excluding zero-coupon debt.
[4]	Includes a portion of structured debt instruments that is reported at fair value.
[5]	Includes credit risk sharing securities issued under our Connecticut Avenue Securities series, which transfers some of the credit risk of our mortgage loans to the investors in these securities.
[6]	Represents our remaining liability resulting from the transfer of financial assets from our condensed consolidated balance sheets that did not qualify as a sale under the accounting guidance for the transfer of financial instruments.

Derivative_Instruments_Derivat

Derivative Instruments Derivatives 1 - Notional and FV Position (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
Asset Derivatives [Abstract]	'		'
Notional amount	$211,443,000,000		$245,573,000,000
Derivatives asset, estimated fair value	1,264,000,000		2,073,000,000
Netting adjustment	-6,897,000,000	[1]	-8,422,000,000	[1]
Derivative Liabilities [Abstract]	'		'
Notional amount	397,139,000,000		380,094,000,000
Derivative liability, estimated fair value	-736,000,000		-1,469,000,000
Table Footnote [Abstract]	'		'
Cash collateral posted for derivative instruments	3,300,000,000		2,000,000,000
Cash collateral received for derivative instruments	780,000,000		1,000,000,000
Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	163,017,000,000		205,736,000,000
Derivatives asset, estimated fair value	7,076,000,000		9,444,000,000
Accrued interest receivable, estimated fair value	696,000,000		786,000,000
Netting adjustment	-6,897,000,000	[2]	-8,422,000,000	[2]
Total net risk management derivatives	875,000,000		1,808,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	335,905,000,000		346,994,000,000
Derivative liability, estimated fair value	-8,651,000,000		-9,695,000,000
Accrued interest payable, estimated fair value	-950,000,000		-930,000,000
Netting adjustment	9,390,000,000	[2]	9,370,000,000	[2]
Total net risk management derivatives	-211,000,000		-1,255,000,000
Mortgage commitment derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	48,426,000,000		39,837,000,000
Derivatives asset, estimated fair value	389,000,000		265,000,000
Netting adjustment	0	[1]	0	[1]
Derivative Liabilities [Abstract]	'		'
Notional amount	61,234,000,000		33,100,000,000
Derivative liability, estimated fair value	-525,000,000		-214,000,000
Netting adjustment	0	[1]	0	[1]
Pay-fixed Swap [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	52,489,000,000		68,637,000,000
Derivatives asset, estimated fair value	2,340,000,000		5,378,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	105,272,000,000		93,428,000,000
Derivative liability, estimated fair value	-6,019,000,000		-4,759,000,000
Receive-fixed Swap [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	66,478,000,000		67,527,000,000
Derivatives asset, estimated fair value	4,179,000,000		3,320,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	133,397,000,000		156,250,000,000
Derivative liability, estimated fair value	-1,629,000,000		-3,813,000,000
Basis Swap [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	13,914,000,000		27,014,000,000
Derivatives asset, estimated fair value	79,000,000		36,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	6,850,000,000		600,000,000
Derivative liability, estimated fair value	-1,000,000		0
Foreign Currency Swap [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	377,000,000		389,000,000
Derivatives asset, estimated fair value	139,000,000		120,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	299,000,000		653,000,000
Derivative liability, estimated fair value	-16,000,000		-38,000,000
Pay-fixed Swaption [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	25,150,000,000		33,400,000,000
Derivatives asset, estimated fair value	94,000,000		445,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	43,525,000,000		48,025,000,000
Derivative liability, estimated fair value	-264,000,000		-600,000,000
Receive-fixed Swaption [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	4,500,000,000		8,000,000,000
Derivatives asset, estimated fair value	216,000,000		117,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	46,525,000,000		48,025,000,000
Derivative liability, estimated fair value	-721,000,000		-484,000,000
Other [Member] | Risk Management Derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	109,000,000	[3]	769,000,000	[3]
Derivatives asset, estimated fair value	29,000,000	[3]	28,000,000	[3]
Derivative Liabilities [Abstract]	'		'
Notional amount	37,000,000	[3]	13,000,000	[3]
Derivative liability, estimated fair value	-1,000,000	[3]	-1,000,000	[3]
Mortgage Commitments to Purchase Whole Loans [Member] | Mortgage commitment derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	7,728,000,000		1,138,000,000
Derivatives asset, estimated fair value	44,000,000		1,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	235,000,000		4,353,000,000
Derivative liability, estimated fair value	0		-31,000,000
Forward Contracts to Purchase Mortgage-related Securities [Member] | Mortgage commitment derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	40,214,000,000		3,276,000,000
Derivatives asset, estimated fair value	343,000,000		4,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	663,000,000		20,861,000,000
Derivative liability, estimated fair value	-2,000,000		-168,000,000
Forward Contracts to Sell Mortgage-related Securities [Member] | Mortgage commitment derivatives [Member]	'		'
Asset Derivatives [Abstract]	'		'
Notional amount	484,000,000		35,423,000,000
Derivatives asset, estimated fair value	2,000,000		260,000,000
Derivative Liabilities [Abstract]	'		'
Notional amount	60,336,000,000		7,886,000,000
Derivative liability, estimated fair value	($523,000,000)		($15,000,000)
[1]	Represents the effect of the right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received and accrued interest.
[2]	The netting adjustment for our risk management derivatives transactions represents the effect of the legal right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received. Cash collateral posted was $3.3 billion and $2.0 billion as of June 30, 2014 and December 31, 2013, respectively. Cash collateral received was $780 million and $1.0 billion as of June 30, 2014 and December 31, 2013, respectively.
[3]	Includes interest rate caps, futures, swap credit enhancements and mortgage insurance contracts that we account for as derivatives. The mortgage insurance contracts have payment provisions that are not based on a notional amount.

Derivative_Instruments_Narrati

Derivative Instruments (Narratives) (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'	'
Aggregate fair value of all derivatives with credit-risk-related contingent features that were in a net liability position	$2,300,000,000	$2,100,000,000
Fair value of collateral posted, aggregated	2,100,000,000	2,000,000,000
Additional collateral required or amount required to immediately settle our position if the credit-risk-related contingent features were triggered	$174,000,000	$130,000,000

Derivative_Instruments_Derivat1

Derivative Instruments Derivatives 2 - FV Gains and Losses (Details) (USD $)	3 Months Ended			6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	($1,246)	$1,188		($2,531)	$1,750
Accrual of periodic settlements	4,904	5,667	[1]	9,642	11,971	[1]
Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	-936	691		-1,876	1,122
Mortgage commitment derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	-310	497		-655	628
Pay-fixed Swap [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	-2,349	8,313		-4,467	10,903
Accrual of periodic settlements	-913	-1,211		-1,816	-2,409
Receive-fixed Swap [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	1,639	-7,123		3,104	-9,033
Accrual of periodic settlements	642	1,012		1,333	1,994
Basis Swap [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	8	-45		43	-72
Foreign Currency Swap [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	17	-63		38	-133
Pay-fixed Swaption [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	62	-468		-37	-451
Receive-fixed Swaption [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	-59	247		-101	268
Other [Member] | Risk Management Derivatives [Member]	'	'		'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'		'	'
Derivative fair value gains (losses), net	3	11		0	21
Accrual of periodic settlements	$14	$18		$27	$34
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.

Income_Taxes_Narratives_Detail

Income Taxes - Narratives (Details) (USD $)	3 Months Ended			6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013
Income Tax Disclosure [Abstract]	'	'		'	'
Provision (benefit) for federal income taxes	$1,752	$1,985	[1]	$4,336	($48,586)	[1],[2]
Effective Income Tax Rate Reconciliation, Percent	32.30%	16.40%		32.50%	-240.60%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%		35.00%	35.00%
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.
[2]	Primarily represented the release of the valuation allowance for our deferred tax assets that generally is directly attributable to each segment based on the nature of the item.

Earnings_Loss_Per_Share_Detail

Earnings (Loss) Per Share (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Earnings Per Share [Abstract]	'		'		'		'
Net Income, Including Portion Attributable to Noncontrolling Interest	$3,667,000,000		$10,095,000,000	[1]	$8,992,000,000		$68,780,000,000	[1]
Net Income Attributable to Noncontrolling Interest	-1,000,000		-11,000,000	[1]	-1,000,000		-11,000,000	[1]
Net income attributable to Fannie Mae	3,666,000,000		10,084,000,000	[1]	8,991,000,000		68,769,000,000	[1]
Dividends distributed or available for distribution to senior preferred stockholder	-3,712,000,000	[2]	-10,243,000,000	[2]	-9,404,000,000	[2]	-69,611,000,000	[2]
Net loss attributable to common stockholders	-46,000,000		-159,000,000		-413,000,000		-842,000,000
Weighted-average common shares outstanding: basic and diluted	5,762,000,000	[3]	5,762,000,000	[3]	5,762,000,000	[3]	5,762,000,000	[3]
Loss per share: basic and diluted	($0.01)		($0.03)		($0.07)		($0.15)
Capital Reserve Amount, current year, Senior Preferred Stock Purchase Agreement, Amendment	2,400,000,000		'		2,400,000,000		'
Capital Reserve Amount, prior year, Senior Preferred Stock Purchase Agreement Amendment	'		$3,000,000,000		'		$3,000,000,000
Weighted-average shares of common stock that would be issued upon the full exercise of the warrant issued to Treasury	4,600,000,000		4,600,000,000		4,600,000,000		4,600,000,000
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.
[2]	Represents our dividend payments to Treasury under the terms of the senior preferred stock. Dividends distributed or available for distribution for the three months ended June 30, 2014 (relating to the dividend period for the three months ended September 30, 2014) were calculated based on our net worth as of June 30, 2014 less the applicable capital reserve amount of $2.4 billion and for the six months ended June 30, 2014 we add dividends paid on June 30, 2014 to this amount. Dividends distributed or available for distribution for the three months ended June 30, 2013 (relating to the dividend period for the three months ended September 30, 2013) were calculated based on our net worth as of June 30, 2013 less the applicable capital reserve amount of $3.0 billion and for the six months ended June 30, 2013 we add dividends paid on June 30, 2013 to this amount.
[3]	Includes 4.6 billion of weighted average shares of common stock that would be issued upon the full exercise of the warrant issued to Treasury from the date the warrant was issued through June 30, 2014.

Segment_Reporting_Narrative_De

Segment Reporting (Narrative) (Details)	6 Months Ended
	Jun. 30, 2014
	segments
Segment Reporting [Abstract]	'
Number of Reportable Segments	3

Segment_Reporting_Segment_Repo1

Segment Reporting Segment Reporting(Details) (USD $)	3 Months Ended				6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	$4,904		$5,667	[1]	$9,642		$11,971	[1]
Benefit for credit losses	1,639		5,383	[1]	2,413		6,340	[1]
Net interest income after benefit for credit losses	6,543		11,050	[1]	12,055		18,311	[1]
Guaranty Fee Income (expense)	41	[2],[3]	51	[1],[2],[3]	86	[2],[3]	105	[1],[2],[3]
Investment gains (losses), net	506		290	[1]	652		408	[1]
Net other-than-temporary impairments	-23		-6	[1]	-74		-15	[1]
Fair value (losses) gains, net	-934		829	[1]	-2,124		1,663	[1]
Debt extinguishment (losses) gains, net	38		27	[1]	38		4	[1]
Gains from partnership investments	35	[4]	115	[1],[4]	80	[4]	174	[1],[4]
Fee and other income (expense)	342		434	[1]	4,652		948	[1]
Administrative expenses	-697		-626	[1]	-1,369		-1,267	[1]
Foreclosed property income	214		332	[1]	476		592	[1]
Temporary Payroll Tax Cut Continuation Act of 2011 (TCCA) Fees	-335		-233		-657		-419
Other expenses	-311		-183	[1]	-487		-310	[1]
Income before federal income taxes	5,419		12,080	[1]	13,328		20,194	[1]
(Provision) benefit for federal income taxes	-1,752		-1,985	[1]	-4,336		48,586	[1],[5]
Net Income, Including Portion Attributable to Noncontrolling Interest	3,667		10,095	[1]	8,992		68,780	[1]
Net Income Attributable to Noncontrolling Interest	-1		-11	[1]	-1		-11	[1]
Net income attributable to Fannie Mae	3,666		10,084	[1]	8,991		68,769	[1]
Single-Family [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	5		-50	[1]	-43		470	[1]
Benefit for credit losses	1,603		5,353	[1]	2,348		6,134	[1]
Net interest income after benefit for credit losses	1,608		5,303	[1]	2,305		6,604	[1]
Guaranty Fee Income (expense)	2,893	[2]	2,544	[1],[2]	5,763	[2]	4,919	[1],[2]
Investment gains (losses), net	-1		1	[1]	-1		3	[1]
Net other-than-temporary impairments	0		0	[1]	0		0	[1]
Fair value (losses) gains, net	-2		-1	[1]	-7		-3	[1]
Debt extinguishment (losses) gains, net	0		0	[1]	0		0	[1]
Gains from partnership investments	0	[4]	0	[1],[4]	0	[4]	0	[1],[4]
Fee and other income (expense)	181		179	[1]	325		351	[1]
Administrative expenses	-458		-419	[1]	-908		-845	[1]
Foreclosed property income	178		328	[1]	435		581	[1]
Other expenses	-237		-154	[1]	-392		-322	[1]
Income before federal income taxes	3,827		7,548	[1]	6,863		10,869	[1]
(Provision) benefit for federal income taxes	-1,133		-1,050	[1]	-2,060		30,528	[1],[5]
Net Income, Including Portion Attributable to Noncontrolling Interest	2,694		6,498	[1]	4,803		41,397	[1]
Net Income Attributable to Noncontrolling Interest	0		0	[1]	0		0	[1]
Net income attributable to Fannie Mae	2,694		6,498	[1]	4,803		41,397	[1]
Multifamily [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	-21		-17	[1]	-43		-28	[1]
Benefit for credit losses	36		30	[1]	65		206	[1]
Net interest income after benefit for credit losses	15		13	[1]	22		178	[1]
Guaranty Fee Income (expense)	317	[2]	300	[1],[2]	628	[2]	591	[1],[2]
Investment gains (losses), net	39		4	[1]	42		11	[1]
Net other-than-temporary impairments	0		0	[1]	0		0	[1]
Fair value (losses) gains, net	0		0	[1]	0		0	[1]
Debt extinguishment (losses) gains, net	0		0	[1]	0		0	[1]
Gains from partnership investments	34	[4]	104	[1],[4]	79	[4]	163	[1],[4]
Fee and other income (expense)	31		38	[1]	55		89	[1]
Administrative expenses	-75		-67	[1]	-148		-137	[1]
Foreclosed property income	36		4	[1]	41		11	[1]
Other expenses	-12		0	[1]	-13		1	[1]
Income before federal income taxes	385		396	[1]	706		907	[1]
(Provision) benefit for federal income taxes	-9		-10	[1]	0		7,978	[1],[5]
Net Income, Including Portion Attributable to Noncontrolling Interest	376		386	[1]	706		8,885	[1]
Net Income Attributable to Noncontrolling Interest	0		0	[1]	0		0	[1]
Net income attributable to Fannie Mae	376		386	[1]	706		8,885	[1]
Capital Markets [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	1,917		2,680	[1]	3,747		5,422	[1]
Benefit for credit losses	0		0	[1]	0		0	[1]
Net interest income after benefit for credit losses	1,917		2,680	[1]	3,747		5,422	[1]
Guaranty Fee Income (expense)	-241	[2]	-283	[1],[2]	-487	[2]	-582	[1],[2]
Investment gains (losses), net	1,648		898	[1]	2,984		2,247	[1]
Net other-than-temporary impairments	-23		-6	[1]	-74		-15	[1]
Fair value (losses) gains, net	-1,098		841	[1]	-2,435		1,716	[1]
Debt extinguishment (losses) gains, net	41		3	[1]	34		-37	[1]
Gains from partnership investments	0	[4]	0	[1],[4]	0	[4]	0	[1],[4]
Fee and other income (expense)	136		255	[1]	4,269		604	[1]
Administrative expenses	-164		-140	[1]	-313		-285	[1]
Foreclosed property income	0		0	[1]	0		0	[1]
Other expenses	-57		-8	[1]	-65		50	[1]
Income before federal income taxes	2,159		4,240	[1]	7,660		9,120	[1]
(Provision) benefit for federal income taxes	-610		-925	[1]	-2,276		10,080	[1],[5]
Net Income, Including Portion Attributable to Noncontrolling Interest	1,549		3,315	[1]	5,384		19,200	[1]
Net Income Attributable to Noncontrolling Interest	0		0	[1]	0		0	[1]
Net income attributable to Fannie Mae	1,549		3,315	[1]	5,384		19,200	[1]
Consolidated Trusts [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	2,739	[6]	2,621	[1],[6]	5,437	[6]	5,218	[1],[6]
Benefit for credit losses	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Net interest income after benefit for credit losses	2,739	[6]	2,621	[1],[6]	5,437	[6]	5,218	[1],[6]
Guaranty Fee Income (expense)	-1,452	[2],[3],[6]	-1,283	[1],[2],[3],[6]	-2,879	[2],[3],[6]	-2,487	[1],[2],[3],[6]
Investment gains (losses), net	-104	[6]	-89	[1],[6]	-162	[6]	-156	[1],[6]
Net other-than-temporary impairments	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Fair value (losses) gains, net	171	[6]	-214	[1],[6]	219	[6]	-418	[1],[6]
Debt extinguishment (losses) gains, net	-3	[6]	24	[1],[6]	4	[6]	41	[1],[6]
Gains from partnership investments	0	[4],[6]	0	[1],[4],[6]	0	[4],[6]	0	[1],[4],[6]
Fee and other income (expense)	-95	[6]	-86	[1],[6]	-171	[6]	-170	[1],[6]
Administrative expenses	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Foreclosed property income	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Other expenses	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Income before federal income taxes	1,256	[6]	973	[1],[6]	2,448	[6]	2,028	[1],[6]
(Provision) benefit for federal income taxes	0	[6]	0	[1],[6]	0	[6]	0	[1],[5],[6]
Net Income, Including Portion Attributable to Noncontrolling Interest	1,256	[6]	973	[1],[6]	2,448	[6]	2,028	[1],[6]
Net Income Attributable to Noncontrolling Interest	0	[6]	0	[1],[6]	0	[6]	0	[1],[6]
Net income attributable to Fannie Mae	1,256	[6]	973	[1],[6]	2,448	[6]	2,028	[1],[6]
Eliminations/Adjustments [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Net interest (loss) income	264	[7],[8]	433	[1],[7],[8]	544	[7],[8]	889	[1],[7],[8]
Benefit for credit losses	0	[7]	0	[1],[7]	0	[7]	0	[1],[7]
Net interest income after benefit for credit losses	264	[7]	433	[1],[7]	544	[7]	889	[1],[7]
Guaranty Fee Income (expense)	-1,476	[2],[3],[7]	-1,227	[1],[2],[3],[7]	-2,939	[2],[3],[7]	-2,336	[1],[2],[3],[7]
Investment gains (losses), net	-1,076	[7],[9]	-524	[1],[7],[9]	-2,211	[7],[9]	-1,697	[1],[7],[9]
Net other-than-temporary impairments	0	[7]	0	[1],[7]	0	[7]	0	[1],[7]
Fair value (losses) gains, net	-5	[10],[7]	203	[1],[10],[7]	99	[10],[7]	368	[1],[10],[7]
Debt extinguishment (losses) gains, net	0	[7]	0	[1],[7]	0	[7]	0	[1],[7]
Gains from partnership investments	1	[4],[7]	11	[1],[4],[7]	1	[4],[7]	11	[1],[4],[7]
Fee and other income (expense)	89	[7]	48	[1],[7]	174	[7]	74	[1],[7]
Administrative expenses	0	[7]	0	[1],[7]	0	[7]	0	[1],[7]
Foreclosed property income	0	[7]	0	[1],[7]	0	[7]	0	[1],[7]
Other expenses	-5	[7]	-21	[1],[7]	-17	[7]	-39	[1],[7]
Income before federal income taxes	-2,208	[7]	-1,077	[1],[7]	-4,349	[7]	-2,730	[1],[7]
(Provision) benefit for federal income taxes	0	[7]	0	[1],[7]	0	[7]	0	[1],[5],[7]
Net Income, Including Portion Attributable to Noncontrolling Interest	-2,208	[7]	-1,077	[1],[7]	-4,349	[7]	-2,730	[1],[7]
Net Income Attributable to Noncontrolling Interest	-1	[11],[7]	-11	[1],[11],[7]	-1	[11],[7]	-11	[1],[11],[7]
Net income attributable to Fannie Mae	-2,209	[7]	-1,088	[1],[7]	-4,350	[7]	-2,741	[1],[7]
US Treasury [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Temporary Payroll Tax Cut Continuation Act of 2011 (TCCA) Fees	-335	[2]	-233	[1],[2]	-657	[2]	-419	[1],[2]
US Treasury [Member] | Single-Family [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Temporary Payroll Tax Cut Continuation Act of 2011 (TCCA) Fees	($335)	[2]	($233)	[1],[2]	($657)	[2]	($419)	[1],[2]
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.
[2]	Includes the impact of a 10 basis point guaranty fee increase implemented pursuant to the TCCA, the incremental revenue from which must be remitted to Treasury. The resulting revenue is included in guaranty fee income and the expense is recognized as “TCCA fees.”
[3]	Represents the guaranty fees paid from consolidated trusts to the Single-Family and Multifamily segments. The adjustment to guaranty fee income in the Eliminations/Adjustments column represents the elimination of the amortization of deferred cash fees related to consolidated trusts that were re-established for segment reporting. Total guaranty fee income related to unconsolidated Fannie Mae MBS trusts and other credit enhancement arrangements is included in fee and other income in our condensed consolidated statements of operations and comprehensive income.
[4]	Gains from partnership investments are included in other expenses in our condensed consolidated statements of operations and comprehensive income.
[5]	Primarily represented the release of the valuation allowance for our deferred tax assets that generally is directly attributable to each segment based on the nature of the item.
[6]	Represents activity related to the assets and liabilities of consolidated trusts in our condensed consolidated balance sheets
[7]	Represents the elimination of intercompany transactions occurring between the three business segments and our consolidated trusts, as well as other adjustments to reconcile to our consolidated results
[8]	Represents the amortization expense of cost basis adjustments on securities in the Capital Markets group’s retained mortgage portfolio that on a GAAP basis are eliminated
[9]	Primarily represents the removal of realized gains and losses on sales of Fannie Mae MBS classified as available-for-sale securities that are issued by consolidated trusts and in the Capital Markets group’s retained mortgage portfolio. The adjustment also includes the removal of securitization gains (losses) recognized in the Capital Markets segment relating to portfolio securitization transactions that do not qualify for sale accounting under GAAP.
[10]	Represents the removal of fair value adjustments on consolidated Fannie Mae MBS classified as trading that are in the Capital Markets group’s retained mortgage portfolio.
[11]	Represents the adjustment from equity method of accounting to consolidated accounting for partnership investments that are consolidated in our consolidated balance sheets.

Equity_Activity_in_OCI_Details

Equity Activity in OCI (Details) (USD $)	3 Months Ended			6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013
Equity [Abstract]	'	'		'	'
Net income	$3,667	$10,095	[1]	$8,992	$68,780	[1]
Other comprehensive income, net of tax effect:	'	'		'	'
Changes in net unrealized gains on AFS securities (net of tax of $119 and $47, respectively, for the three months ended and net of tax of $303 and $396, respectively, for the six months ended)	221	88		561	735
Reclassification adjustment for OTTI recognized in net income (net of tax of $8 and $2, respectively, for the three months ended and net of tax of $26 and $5, respectively, for the six months ended)	15	4		48	10
Reclassification adjustment for gains on AFS securities included in net income (net of tax of $104 and $40, respectively, for the three months ended and net of tax of $104 and $43, respectively, for the six months ended)	-191	-75		-192	-80
Other	0	149		0	155
Total other comprehensive income	45	166		417	820
Total comprehensive income	3,712	10,261		9,409	69,600
Other Comprehensive (Income) Loss Parenthetical Disclosures [Abstract]	'	'		'	'
Changes in net unrealized gains on AFS securities, tax	119	47		303	396
Reclassification adjustment for OTTI recognized in net income, tax	8	2		26	5
Reclassification adjustment for gains on AFS securities included in net income, tax	$104	$40		$104	$43
[1]	Certain prior period amounts have been reclassified to conform with the current period presentation.

Equity_AOCI_Details

Equity AOCI (Details) (USD $)	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Equity [Abstract]	'	'	'	'	'	'
Net unrealized Gains on AFS securities for which we have not recorded OTTI, net of tax	$561	'	$365	'	'	'
Net unrealized gains on AFS securities for which we have recorded OTTI, net of tax	1,483	'	1,262	'	'	'
Prior service cost and actuarial losses, net of amortization, net of tax	-395	'	-395	'	'	'
Other Losses	-29	'	-29	'	'	'
Accumulated other comprehensive income	$1,620	$1,575	$1,203	$1,204	$1,038	$384

Equity_Changes_in_AOCI_Details

Equity Changes in AOCI (Details) (USD $)	3 Months Ended				6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]	'		'		'		'
Beginning balance	$1,575		$1,038		$1,203		$384
OCI before reclassifications	221		233		561		880
Amounts reclassified from OCI	-176		-67		-144		-60
Total other comprehensive income	45		166		417		820
Ending balance	1,620		1,204		1,620		1,204
Available-for-Sale Securities [Member]	'		'		'		'
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]	'		'		'		'
Beginning balance	1,999	[1]	1,582	[1]	1,627	[1]	934	[1]
OCI before reclassifications	221	[1]	88	[1]	561	[1]	735	[1]
Amounts reclassified from OCI	-176	[1]	-71	[1]	-144	[1]	-70	[1]
Total other comprehensive income	45	[1]	17	[1]	417	[1]	665	[1]
Ending balance	2,044	[1]	1,599	[1]	2,044	[1]	1,599	[1]
Accumulated Other Comprehensive Income (Loss), Other [Member]	'		'		'		'
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]	'		'		'		'
Beginning balance	-424		-544	[2]	-424		-550	[2]
OCI before reclassifications	0		145	[2]	0		145	[2]
Amounts reclassified from OCI	0		4	[2]	0		10	[2]
Total other comprehensive income	0		149	[2]	0		155	[2]
Ending balance	($424)		($395)	[2]	($424)		($395)	[2]
[1]	The amounts reclassified from AOCI represent the gain or loss recognized in earnings due to a sale of an AFS security or the recognition of a net impairment recognized in earnings, which are recorded in “Investments gains, net” and “Net other-than-temporary impairments,” respectively, in our condensed consolidated statements of operations.
[2]	The amounts reclassified from AOCI represent activity from our defined benefit pension plans, which is recorded in “Salaries and employee benefits” in our condensed consolidated statements of operations.

Concentrations_of_Credit_Risk_1

Concentrations of Credit Risk Concentration of Credit Risk (Narrative) (Details) (USD $)

Jun. 30, 2014

Dec. 31, 2013

Mar. 07, 2014

Dec. 31, 2013

Jul. 01, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

PMI Mortgage Insurance Co. [Member]

PMI Mortgage Insurance Co. [Member]

Republic Mortgage Insurance Company and Affiliate [Member]

Republic Mortgage Insurance Company and Affiliate [Member]

Mortgage Sellers and Servicers [Member]

Mortgage Sellers and Servicers [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Guaranty Book of Business [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Single-Family [Member]

Multifamily [Member]

Multifamily [Member]

Multifamily [Member]

Multifamily [Member]

insurers

insurers

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

servicers

servicers

Unpaid Principal Balance [Member]

Unpaid Principal Balance [Member]

servicers

servicers

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Insurance Service Provider Concentration Risk [Member]

Insurance Service Provider Concentration Risk [Member]

Insurance Service Provider Concentration Risk [Member]

Credit Concentration Risk [Member]

Credit Concentration Risk [Member]

Largest Mortgage Servicers, Including Their Affiliates [Member]

Largest Mortgage Servicers, Including Their Affiliates [Member]

Mortgage Insurance Companies [Member]

Mortgage Insurance Companies [Member]

Largest Mortgage Servicers, Including Their Affiliates [Member]

Largest Mortgage Servicers, Including Their Affiliates [Member]

Concentration of Credit Risk [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of mortgage servicers, including their affiliates, which serviced the majority of our guaranty book of business

'

'

'

'

'

'

'

'

5

5

'

'

'

'

'

'

'

10

10

'

'

Percentage of concentration risk

'

'

'

'

'

'

'

'

'

'

'

'

48.00%

49.00%

13.00%

79.00%

78.00%

'

'

66.00%

65.00%

Mortgage insurance coverage risk in force

'

'

'

'

'

'

'

'

'

'

$104,600,000,000

$102,500,000,000

'

'

'

'

'

'

'

'

'

Mortgage insurance coverage risk in force as percentage

'

'

'

'

'

'

'

'

'

'

4.00%

4.00%

'

'

'

'

'

'

'

'

'

Primary mortgage insurance coverage risk in force

'

'

'

'

'

'

'

'

'

'

103,600,000,000

101,400,000,000

'

'

'

'

'

'

'

'

'

Pool mortgage insurance coverage risk in force

'

'

'

'

'

'

'

'

'

'

959,000,000

1,100,000,000

'

'

'

'

'

'

'

'

'

Number of mortgage insurance companies provided majority of our mortgage insurance

'

'

'

'

'

'

'

'

4

4

'

'

'

'

'

'

'

'

'

'

'

Number of mortgage Insurers publicly disclosed credit quality deterioration

'

'

'

'

'

'

'

'

3

'

'

'

'

'

'

'

'

'

'

'

'

Mortgage insurance coverage risk in force, insurers with credit quality deterioration

'

'

'

'

'

'

'

'

'

'

'

'

'

'

13,500,000,000

'

'

'

'

'

'

Mortgage insurance coverage risk in force, Insurance claim, percentage to be paid in cash by mortgage insurer

'

'

67.00%

55.00%

100.00%

60.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Receivable from claims on insured, defaulted loans excluding government insured loans

2,000,000,000

2,100,000,000

'

'

'

'

328,000,000

402,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Allowance for mortgage insurance receivable

$611,000,000

$655,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Concentrations_of_Credit_Risk_2

Concentrations of Credit Risk Estimated Benefit from Mortgage Insurers (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Risks and Uncertainties [Abstract]	'		'
Contractual mortgage insurance benefit	$5,886		$6,751
Less: Collectability adjustment	354	[1]	431	[1]
Estimated benefit included in total loss reserves	$5,532		$6,320
[1]	Represents an adjustment that reduces the contractual benefit for our assessment of our mortgage insurer counterparties’ inability to fully pay the contractual mortgage insurance claims.

Netting_Arrangements_Netting_A

Netting Arrangements Netting Arrangements Table (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
Assets	'		'
Derivative assets, gross amount	$8,133,000,000		$8,756,000,000
Derivative assets, gross amount offset	-6,897,000,000	[1]	-8,422,000,000	[1]
Derivative assets, net amount presented in the condensed consolidated balance sheets	1,236,000,000	[2]	334,000,000	[2]
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	-145,000,000	[3]	-83,000,000	[3]
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	-16,000,000	[4]	-20,000,000	[4]
Derivative assets, net amount	1,075,000,000		231,000,000
Securities purchased under agreements to resell or similar arrangements, gross amount	32,250,000,000	[5]	50,565,000,000	[5]
Securities purchased under agreements to resell or similar arrangements, gross amount offset	0	[1],[5]	0	[1],[5]
Securities purchased under agreements to resell or similar arrangements, net amount presented in the condensed consolidated balance sheets	32,250,000,000	[5]	50,565,000,000	[5]
Securities purchased under agreements to resell, under master netting arrangement, amounts not offset in the condensed consolidated balance sheets, financial instruments	0	[3],[5]	0	[3],[5]
Securities purchased under agreements to resell or similar arrangements, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	-32,249,000,000	[4],[5]	-50,565,000,000	[4],[5]
Securities purchased under agreements to resell or similar arrangements, net amount	1,000,000	[5]	0	[5]
Total assets, gross amount	40,383,000,000		59,321,000,000
Total assets, gross amount offset	-6,897,000,000	[1]	-8,422,000,000	[1]
Total assets, net amount presented in the condensed consolidated balance sheets	33,486,000,000		50,899,000,000
Total assets, under master netting arrangements, not offset in the condensed consolidated balance sheets, financial instruments	-145,000,000	[3]	-83,000,000	[3]
Total assets, under master netting arrangements, not offset in the condensed consolidated balance sheets, collateral	-32,265,000,000	[4]	-50,585,000,000	[4]
Total assets, net amount	1,076,000,000		231,000,000
Derivative assets not subject to an enforceable master netting arrangement or similar agreement	28,000,000		1,700,000,000
Liabilities:	'		'
Total liabilities, gross amount	-10,125,000,000		-9,717,000,000
Total liabilities, gross amount offset	9,390,000,000	[1]	9,370,000,000	[1]
Total liabilities, net amount presented in the condensed consolidated balance sheets	-735,000,000	[2]	-347,000,000	[2]
Total liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	145,000,000	[3]	83,000,000	[3]
Total liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	0	[4]	0	[4]
Total liabilities, net amount	-590,000,000		-264,000,000
Derivative liabilities not subject to an enforceable master netting arrangement or similar agreement	1,000,000		1,100,000,000
Risk Management Derivatives [Member]	'		'
Assets	'		'
Derivative assets, gross amount offset	-6,897,000,000	[6]	-8,422,000,000	[6]
Liabilities:	'		'
Derivative liabilities, gross amount offset	9,390,000,000	[6]	9,370,000,000	[6]
Mortgage related commitment derivatives [Member]	'		'
Assets	'		'
Derivative assets, gross amount	389,000,000		265,000,000
Derivative assets, gross amount offset	0	[1]	0	[1]
Derivative assets, net amount presented in the condensed consolidated balance sheets	389,000,000		265,000,000
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	-145,000,000	[3]	-83,000,000	[3]
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	-4,000,000	[4]	0	[4]
Derivative assets, net amount	240,000,000		182,000,000
Liabilities:	'		'
Derivative liabilities, gross amount	-525,000,000		-214,000,000
Derivative liabilities, gross amount offset	0	[1]	0	[1]
Derivative liabilities, net amount presented in the condensed consolidated balance sheets	-525,000,000		-214,000,000
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	145,000,000	[3]	83,000,000	[3]
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	0	[4]	0	[4]
Derivative liabilities, net amount	-380,000,000		-131,000,000
OTC Risk Management Derivatives [Member] | Risk Management Derivatives [Member]	'		'
Assets	'		'
Derivative assets, gross amount	6,795,000,000		8,491,000,000
Derivative assets, gross amount offset	-6,777,000,000	[1]	-8,422,000,000	[1]
Derivative assets, net amount presented in the condensed consolidated balance sheets	18,000,000		69,000,000
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	0	[3]	0	[3]
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	-12,000,000	[4]	-20,000,000	[4]
Derivative assets, net amount	6,000,000		49,000,000
Liabilities:	'		'
Derivative liabilities, gross amount	-8,352,000,000		-9,503,000,000
Derivative liabilities, gross amount offset	8,142,000,000	[1]	9,370,000,000	[1]
Derivative liabilities, net amount presented in the condensed consolidated balance sheets	-210,000,000		-133,000,000
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	0	[3]	0	[3]
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	0	[4]	0	[4]
Derivative liabilities, net amount	-210,000,000		-133,000,000
OTC-Cleared Risk Management Derivatives [Member] | Risk Management Derivatives [Member]	'		'
Assets	'		'
Derivative assets, gross amount	949,000,000	[7]	'
Derivative assets, gross amount offset	-120,000,000	[1],[7]	'
Derivative assets, net amount presented in the condensed consolidated balance sheets	829,000,000	[7]	'
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	0	[3],[7]	'
Derivative assets, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	0	[4],[7]	'
Derivative assets, net amount	829,000,000	[7]	'
Liabilities:	'		'
Derivative liabilities, gross amount	-1,248,000,000	[7]	'
Derivative liabilities, gross amount offset	1,248,000,000	[1],[7]	'
Derivative liabilities, net amount presented in the condensed consolidated balance sheets	0	[7]	'
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, financial instruments	0	[3],[7]	'
Derivative liabilities, under master netting arrangements, amounts not offset in the condensed consolidated balance sheets, collateral	0	[4],[7]	'
Derivative liabilities, net amount	0	[7]	'
Cash and cash equivalents [Member]	'		'
Assets	'		'
Securities purchased under agreements to resell or similar arrangements	$15,600,000,000		$11,600,000,000
[1]	Represents the effect of the right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received and accrued interest.
[2]	Excludes derivative assets of $28 million and $1.7 billion and derivative liabilities of $1 million and $1.1 billion recognized in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively, that are not subject to enforceable master netting arrangements.
[3]	Mortgage commitment derivative amounts reflect where we have recognized both an asset and a liability with the same counterparty under an enforceable master netting arrangement but we have not elected to offset the related amounts in our condensed consolidated balance sheets.
[4]	Represents collateral posted or received that has neither been recognized nor offset in our condensed consolidated balance sheets. Does not include collateral held in excess of our exposure.
[5]	Includes $15.6 billion and $11.6 billion of securities purchased under agreements to resell or similar arrangements classified as “Cash and cash equivalents” in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively.
[6]	The netting adjustment for our risk management derivatives transactions represents the effect of the legal right to offset under legally enforceable master netting arrangements to settle with the same counterparty on a net basis, including cash collateral posted and received. Cash collateral posted was $3.3 billion and $2.0 billion as of June 30, 2014 and December 31, 2013, respectively. Cash collateral received was $780 million and $1.0 billion as of June 30, 2014 and December 31, 2013, respectively.
[7]	As of June 30, 2014, we net OTC-cleared derivative assets and derivative liabilities where we have enforceable master netting arrangements.

Netting_Arrangements_Details

Netting Arrangements (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Securities Purchased under Agreements to Resell or Similar Arrangements [Member]	'	'
Securities Received as Collateral [Abstract]	'	'
Fair value of non-cash collateral accepted	$32,300,000,000	$50,700,000,000
Fair value of non-cash collateral accepted that can be resold or repledged	29,000,000,000	39,800,000,000
Fair value of securities accepted as collateral that have been resold or repledged	0	0
OTC Risk Management Derivatives [Member]	'	'
Securities Received as Collateral [Abstract]	'	'
Fair value of non-cash collateral accepted	$12,000,000	$24,000,000

Fair_Value_Recurring_Changes_i

Fair Value Recurring Changes in Fair Value (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	$3,432		$1,308
Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Liabilities [Abstract]	'		'
Long-term debt, fair value	16,420		14,976
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	13,083		16,306
Available-for-sale securities	0		0
Mortgage loans held for investment, at fair value	0		0
Total assets at fair value	47,967		52,939
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Liabilities [Abstract]	'		'
Total liabilities at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	10,878		11,688
Available-for-sale securities	17,216		19,159
Mortgage loans held for investment, at fair value	2,649,758		2,599,667
Total assets at fair value	2,722,513		2,694,859
Other assets [Abstract]	'		'
Derivatives assets at fair value	8,022		10,430
Liabilities [Abstract]	'		'
Total liabilities at fair value	3,253,326		3,231,253
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	10,007		10,734
Significant Other Observable Inputs (Level 2) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	29,361		29,920
Liabilities [Abstract]	'		'
Long-term debt, fair value	398,264		463,991
Significant Other Observable Inputs (Level 2) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	2,620,397		2,569,747
Liabilities [Abstract]	'		'
Long-term debt, fair value	2,754,120		2,684,224
Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	2,669		2,774
Available-for-sale securities	16,810		19,012
Mortgage loans held for investment, at fair value	410,625		392,355
Total assets at fair value	432,006		415,630
Other assets [Abstract]	'		'
Derivatives assets at fair value	139		65
Liabilities [Abstract]	'		'
Total liabilities at fair value	20,006		19,611
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	119		105
Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	219,051		215,960
Liabilities [Abstract]	'		'
Long-term debt, fair value	940		1,557
Significant Unobservable Inputs (Level 3) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	191,574		176,395
Liabilities [Abstract]	'		'
Long-term debt, fair value	15,054		13,362
Netting Adjustment [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Mortgage loans held for investment, at fair value	0		0
Total assets at fair value	-6,897		-8,422
Other assets [Abstract]	'		'
Derivatives assets at fair value	-6,897		-8,422
Liabilities [Abstract]	'		'
Total liabilities at fair value	-9,390		-9,370
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	-9,390		-9,370
Netting Adjustment [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Netting Adjustment [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Estimated Fair Value [Member]	'		'
Assets [Abstract]	'		'
Trading securities	26,630		30,768
Available-for-sale securities	34,026		38,171
Mortgage loans held for investment, at fair value	3,060,383		2,992,022
Total assets at fair value	3,195,589		3,155,006
Other assets [Abstract]	'		'
Derivatives assets at fair value	1,264		2,073
Liabilities [Abstract]	'		'
Total liabilities at fair value	3,263,942		3,241,494
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	736		1,469
Estimated Fair Value [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	248,412		245,880
Liabilities [Abstract]	'		'
Long-term debt, fair value	399,204		465,548
Estimated Fair Value [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	2,811,971		2,746,142
Liabilities [Abstract]	'		'
Long-term debt, fair value	2,769,174		2,697,586
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	13,083		16,306
Available-for-sale securities	0		0
Total assets at fair value	13,083		16,306
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Total liabilities at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Swaps [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Swaptions [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Netting adjustment [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage commitment derivatives [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fannie Mae [Member] | Senior Fixed [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	'		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0		0
Liabilities [Abstract]	'		'
Long-term debt, fair value	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Freddie Mac [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Ginnie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Alt-A private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Subprime private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | CMBS [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage revenue bonds [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Other [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | U.S. Treasury securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	13,083		16,306
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	10,878		11,688
Available-for-sale securities	17,216		19,159
Total assets at fair value	48,701		52,841
Other assets [Abstract]	'		'
Derivatives assets at fair value	8,022		10,430
Liabilities [Abstract]	'		'
Long-term debt, fair value	19,029		14,811
Total liabilities at fair value	29,036		25,545
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	10,007		10,734
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Swaps [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	7,347		9,604
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	8,497		9,444
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Swaptions [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	310		561
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	985		1,084
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Netting adjustment [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage commitment derivatives [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	365		265
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	525		206
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	3,107		353
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fannie Mae [Member] | Senior Fixed [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	'		353
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	3,107		0
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	12,585		11,564
Liabilities [Abstract]	'		'
Long-term debt, fair value	15,922		14,458
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	5,686		5,828
Available-for-sale securities	6,020		6,566
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Freddie Mac [Member]	'		'
Assets [Abstract]	'		'
Trading securities	1,766		1,837
Available-for-sale securities	6,193		6,834
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Ginnie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	234		407
Available-for-sale securities	528		588
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Alt-A private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	551		898
Available-for-sale securities	2,964		3,558
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Subprime private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | CMBS [Member]	'		'
Assets [Abstract]	'		'
Trading securities	2,641		2,718
Available-for-sale securities	1,508		1,606
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage revenue bonds [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		3
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | Other [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	3		4
Recurring Fair Value Measurements [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets [Abstract]	'		'
Trading securities	2,669		2,774
Available-for-sale securities	16,810		19,012
Total assets at fair value	22,149		24,555
Other assets [Abstract]	'		'
Derivatives assets at fair value	139		65
Liabilities [Abstract]	'		'
Long-term debt, fair value	823		1,473
Total liabilities at fair value	942		1,578
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	119		105
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Swaps [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	86		36
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	118		96
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Swaptions [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		1
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	29		28
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	1		1
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Netting adjustment [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage commitment derivatives [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	24		0
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0		8
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	325		955
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member] | Senior Fixed [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	'		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	325		955
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	2,531		2,704
Liabilities [Abstract]	'		'
Long-term debt, fair value	498		518
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		42
Available-for-sale securities	2		7
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Freddie Mac [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		2
Available-for-sale securities	9		8
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Ginnie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Alt-A private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	643		618
Available-for-sale securities	3,717		3,791
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Subprime private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	1,282		1,448
Available-for-sale securities	5,705		7,068
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | CMBS [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Available-for-sale securities	0		0
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage revenue bonds [Member]	'		'
Assets [Abstract]	'		'
Trading securities	643		565
Available-for-sale securities	4,560		5,253
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | Other [Member]	'		'
Assets [Abstract]	'		'
Trading securities	101		99
Available-for-sale securities	2,817		2,885
Recurring Fair Value Measurements [Member] | Significant Unobservable Inputs (Level 3) [Member] | U.S. Treasury securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0		0
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Total assets at fair value	-6,897	[1]	-8,422	[1]
Other assets [Abstract]	'		'
Derivatives assets at fair value	-6,897	[1]	-8,422	[1]
Liabilities [Abstract]	'		'
Long-term debt, fair value	0	[1]	0	[1]
Total liabilities at fair value	-9,390	[1]	-9,370	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	-9,390	[1]	-9,370	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Swaps [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0	[1]	0	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Swaptions [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0	[1]	0	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Other [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0	[1]	0	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Netting adjustment [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	-6,897	[1]	-8,422	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	-9,390	[1]	-9,370	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Mortgage commitment derivatives [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	0	[1]	0	[1]
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Fannie Mae [Member] | Senior Fixed [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	'		0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	0	[1]	0	[1]
Liabilities [Abstract]	'		'
Long-term debt, fair value	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Freddie Mac [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Ginnie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Alt-A private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Subprime private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | CMBS [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Mortgage revenue bonds [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | Other [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Available-for-sale securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Netting Adjustment [Member] | U.S. Treasury securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	0	[1]	0	[1]
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member]	'		'
Assets [Abstract]	'		'
Trading securities	26,630		30,768
Available-for-sale securities	34,026		38,171
Total assets at fair value	77,036		85,280
Other assets [Abstract]	'		'
Derivatives assets at fair value	1,264		2,073
Liabilities [Abstract]	'		'
Long-term debt, fair value	19,852		16,284
Total liabilities at fair value	20,588		17,753
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	736		1,469
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Swaps [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	7,433		9,640
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	8,615		9,540
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Swaptions [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	310		562
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	985		1,084
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Other [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	29		28
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	1		1
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Netting adjustment [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	-6,897		-8,422
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	-9,390		-9,370
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Mortgage commitment derivatives [Member]	'		'
Other assets [Abstract]	'		'
Derivatives assets at fair value	389		265
Other liabilities [Abstract]	'		'
Derivative liabilities at fair value	525		214
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Fannie Mae [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	3,432		1,308
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Fannie Mae [Member] | Senior Fixed [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	'		353
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Liabilities [Abstract]	'		'
Long-term debt, fair value	3,432		955
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Consolidated Trusts [Member]	'		'
Assets [Abstract]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Liabilities [Abstract]	'		'
Long-term debt, fair value	16,420		14,976
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Fannie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	5,686		5,870
Available-for-sale securities	6,022		6,573
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Freddie Mac [Member]	'		'
Assets [Abstract]	'		'
Trading securities	1,766		1,839
Available-for-sale securities	6,202		6,842
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Ginnie Mae [Member]	'		'
Assets [Abstract]	'		'
Trading securities	234		407
Available-for-sale securities	528		588
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Alt-A private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	1,194		1,516
Available-for-sale securities	6,681		7,349
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Subprime private-label securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	1,282		1,448
Available-for-sale securities	5,705		7,068
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | CMBS [Member]	'		'
Assets [Abstract]	'		'
Trading securities	2,641		2,718
Available-for-sale securities	1,508		1,606
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Mortgage revenue bonds [Member]	'		'
Assets [Abstract]	'		'
Trading securities	643		565
Available-for-sale securities	4,560		5,256
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | Other [Member]	'		'
Assets [Abstract]	'		'
Trading securities	101		99
Available-for-sale securities	2,820		2,889
Recurring Fair Value Measurements [Member] | Estimated Fair Value [Member] | U.S. Treasury securities [Member]	'		'
Assets [Abstract]	'		'
Trading securities	$13,083		$16,306
[1]	Derivative contracts are reported on a gross basis by level. The netting adjustment represents the effect of the legal right to offset under legally enforceable master netting agreements to settle with the same counterparty on a net basis, including cash collateral posted and received.

Fair_Value_Level_3_Reconciliat

Fair Value Level 3 Reconciliation (Details) (USD $)	3 Months Ended				6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Total Gains or (Losses) (realized/unrealized) Included in Net Income	$703		$38		$835		$283
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	-417		-3		-531		-135
Interest Income [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Total Gains or (Losses) (realized/unrealized) Included in Net Income	70		70		140		125
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0		0		0		0
Fair Value Gains, net [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Total Gains or (Losses) (realized/unrealized) Included in Net Income	329		-31		435		161
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	-417		-3		-531		-135
Net Other-than-Temporary Impairments [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Total Gains or (Losses) (realized/unrealized) Included in Net Income	-19		-4		-64		-9
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0		0		0		0
Other [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Total Gains or (Losses) (realized/unrealized) Included in Net Income	323		3		324		6
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0		0		0		0
Trading securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	2,811		2,752		2,774		2,286
Total Gains or (Losses) (realized/unrealized) Included in Net Income	235		47		374		287
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-264	[2]	0	[2]	-264	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-62	[3]	-88	[3]	-157	[3]	-143	[3]
Transfers out of Level 3	-67	[4]	-162	[4]	-184	[4]	-206	[4]
Transfers into Level 3	16	[4]	410	[4]	126	[4]	735	[4]
Ending Balance	2,669		2,959		2,669		2,959
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	336	[5]	45	[5]	474	[5]	281	[5]
Trading securities [Member] | Fannie Mae [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	'		61		42		68
Total Gains or (Losses) (realized/unrealized) Included in Net Income	'		-3		-1		-6
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	'		0	[1]	0	[1]	0	[1]
Purchases	'		0	[2]	0	[2]	0	[2]
Sales	'		0	[2]	0	[2]	0	[2]
Issues	'		0	[3]	0	[3]	0	[3]
Settlements	'		-6	[3]	-2	[3]	-10	[3]
Transfers out of Level 3	'		0	[4]	-39	[4]	0	[4]
Transfers into Level 3	'		0	[4]	0	[4]	0	[4]
Ending Balance	0		52		0		52
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	'		-3	[5]	0	[5]	-6	[5]
Trading securities [Member] | Freddie Mac [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	'		2		2		2
Total Gains or (Losses) (realized/unrealized) Included in Net Income	'		0		0		0
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	'		0	[1]	0	[1]	0	[1]
Purchases	'		0	[2]	0	[2]	0	[2]
Sales	'		0	[2]	0	[2]	0	[2]
Issues	'		0	[3]	0	[3]	0	[3]
Settlements	'		0	[3]	0	[3]	0	[3]
Transfers out of Level 3	'		0	[4]	-2	[4]	0	[4]
Transfers into Level 3	'		0	[4]	0	[4]	0	[4]
Ending Balance	0		2		0		2
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	'		0	[5]	0	[5]	0	[5]
Trading securities [Member] | Ginnie Mae [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	'		0		'		1
Total Gains or (Losses) (realized/unrealized) Included in Net Income	'		0		'		0
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	'		0	[1]	'		0	[1]
Purchases	'		0	[2]	'		0	[2]
Sales	'		0	[2]	'		0	[2]
Issues	'		0	[3]	'		0	[3]
Settlements	'		0	[3]	'		-1	[3]
Transfers out of Level 3	'		0	[4]	'		0	[4]
Transfers into Level 3	'		2	[4]	'		2	[4]
Ending Balance	'		2		'		2
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	'		0	[5]	'		0	[5]
Trading securities [Member] | Alt-A private-label securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	655		464		618		104
Total Gains or (Losses) (realized/unrealized) Included in Net Income	84		32		103		127
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-23	[2]	0	[2]	-23	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-22	[3]	-39	[3]	-38	[3]	-55	[3]
Transfers out of Level 3	-67	[4]	-162	[4]	-143	[4]	-206	[4]
Transfers into Level 3	16	[4]	408	[4]	126	[4]	733	[4]
Ending Balance	643		703		643		703
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	84	[5]	31	[5]	101	[5]	121	[5]
Trading securities [Member] | Subprime private-label securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	1,453		1,446		1,448		1,319
Total Gains or (Losses) (realized/unrealized) Included in Net Income	103		80		179		239
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-241	[2]	0	[2]	-241	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-33	[3]	-38	[3]	-104	[3]	-70	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	1,282		1,488		1,282		1,488
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	204	[5]	79	[5]	280	[5]	239	[5]
Trading securities [Member] | Mortgage revenue bonds [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	601		661		565		675
Total Gains or (Losses) (realized/unrealized) Included in Net Income	44		-56		84		-69
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-2	[3]	-2	[3]	-6	[3]	-3	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	643		603		643		603
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	44	[5]	-56	[5]	84	[5]	-69	[5]
Trading securities [Member] | Other [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	102		118		99		117
Total Gains or (Losses) (realized/unrealized) Included in Net Income	4		-6		9		-4
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-5	[3]	-3	[3]	-7	[3]	-4	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	101		109		101		109
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	4	[5]	-6	[5]	9	[5]	-4	[5]
Available-for-sale securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	18,463		24,451		19,012		25,034
Total Gains or (Losses) (realized/unrealized) Included in Net Income	367		70		396		125
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	79	[1]	283	[1]	605	[1]	1,193	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-1,708	[2]	0	[2]	-1,727	[2]	-19	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-889	[3]	-1,502	[3]	-1,753	[3]	-2,606	[3]
Transfers out of Level 3	-269	[4]	-773	[4]	-880	[4]	-1,979	[4]
Transfers into Level 3	767	[4]	1,811	[4]	1,157	[4]	2,592	[4]
Ending Balance	16,810		24,340		16,810		24,340
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Fannie Mae [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	5		12		7		29
Total Gains or (Losses) (realized/unrealized) Included in Net Income	0		0		0		0
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	-1	[1]	0	[1]	-1	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-1	[3]	-1	[3]	-1	[3]	-4	[3]
Transfers out of Level 3	-4	[4]	0	[4]	-6	[4]	-14	[4]
Transfers into Level 3	2	[4]	0	[4]	2	[4]	0	[4]
Ending Balance	2		10		2		10
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Freddie Mac [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	8		9		8		10
Total Gains or (Losses) (realized/unrealized) Included in Net Income	0		0		0		0
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	-1	[1]	0	[1]	-1	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	0	[3]	0	[3]	0	[3]	-1	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	1	[4]	1	[4]	1	[4]	1	[4]
Ending Balance	9		9		9		9
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Alt-A private-label securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	3,570		6,112		3,791		6,564
Total Gains or (Losses) (realized/unrealized) Included in Net Income	103		11		116		20
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	-24	[1]	249	[1]	49	[1]	467	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-320	[2]	0	[2]	-320	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-111	[3]	-401	[3]	-199	[3]	-669	[3]
Transfers out of Level 3	-265	[4]	-773	[4]	-874	[4]	-1,965	[4]
Transfers into Level 3	764	[4]	1,810	[4]	1,154	[4]	2,591	[4]
Ending Balance	3,717		7,008		3,717		7,008
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Subprime private-label securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	7,030		7,868		7,068		7,447
Total Gains or (Losses) (realized/unrealized) Included in Net Income	268		46		301		90
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	-38	[1]	234	[1]	181	[1]	911	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-1,349	[2]	0	[2]	-1,349	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-206	[3]	-286	[3]	-496	[3]	-586	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	5,705		7,862		5,705		7,862
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Mortgage revenue bonds [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	5,006		7,351		5,253		7,837
Total Gains or (Losses) (realized/unrealized) Included in Net Income	-7		12		-27		10
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	87	[1]	-253	[1]	280	[1]	-282	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	-39	[2]	0	[2]	-58	[2]	-19	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-487	[3]	-710	[3]	-888	[3]	-1,146	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	4,560		6,400		4,560		6,400
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Available-for-sale securities [Member] | Other [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	2,844		3,099		2,885		3,147
Total Gains or (Losses) (realized/unrealized) Included in Net Income	3		1		6		5
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	54	[1]	55	[1]	95	[1]	99	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-84	[3]	-104	[3]	-169	[3]	-200	[3]
Transfers out of Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	2,817		3,051		2,817		3,051
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	0	[5]	0	[5]	0	[5]	0	[5]
Mortgage Loans [Member] | Consolidated Trusts [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	2,608		2,882		2,704		2,634
Total Gains or (Losses) (realized/unrealized) Included in Net Income	102		30		127		57
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	7	[2]	85	[2]	31	[2]	243	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-85	[3]	-122	[3]	-166	[3]	-234	[3]
Transfers out of Level 3	-165	[4]	-51	[4]	-313	[4]	-89	[4]
Transfers into Level 3	64	[4]	137	[4]	148	[4]	350	[4]
Ending Balance	2,531		2,961		2,531		2,961
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	86	[5]	25	[5]	94	[5]	-393	[5]
Net derivatives [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	-23		-7		-40		14
Total Gains or (Losses) (realized/unrealized) Included in Net Income	47		-89		77		-129
Total Gains or (Losses) (realized/unrealized) Included in Other Comprehensive Income	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	0	[3]	0	[3]
Settlements	-4	[3]	31	[3]	-16	[3]	54	[3]
Transfers out of Level 3	0	[4]	16	[4]	-1	[4]	16	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	-4	[4]
Ending Balance	20		-49		20		-49
Net unrealized gains (losses) included in net income related to assets and liabilities still held at period end	41	[5]	-44	[5]	54	[5]	-61	[5]
Long-term debt [Member]	'		'		'		'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	-816		-1,460		-1,473		-1,528
Total (Losses) Gains (Realized/Unrealized) Included in Net Loss	-48		-20		-139		-57
Total Gains or (Losses) Included in Other Comprehensive Income (Loss)	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	-1	[3]	-5	[3]	-751	[3]	-20	[3]
Settlements	17	[3]	56	[3]	55	[3]	105	[3]
Transfers out of Level 3	47	[4]	57	[4]	1,531	[4]	170	[4]
Transfers into Level 3	-22	[4]	-42	[4]	-46	[4]	-84	[4]
Ending Balance	-823		-1,414		-823		-1,414
Net Unrealized (Loss) Gain Included in Net Loss Related to Liabilities Still Held at period end	-46	[5]	-23	[5]	-91	[5]	308	[5]
Long-term debt [Member] | Consolidated Trusts [Member]	'		'		'		'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	-506		-1,077		-518		-1,128
Total (Losses) Gains (Realized/Unrealized) Included in Net Loss	-33		-66		-34		-120
Total Gains or (Losses) Included in Other Comprehensive Income (Loss)	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	-1	[3]	-5	[3]	-1	[3]	-20	[3]
Settlements	17	[3]	56	[3]	35	[3]	105	[3]
Transfers out of Level 3	47	[4]	57	[4]	66	[4]	170	[4]
Transfers into Level 3	-22	[4]	-42	[4]	-46	[4]	-84	[4]
Ending Balance	-498		-1,077		-498		-1,077
Net Unrealized (Loss) Gain Included in Net Loss Related to Liabilities Still Held at period end	-31	[5]	-69	[5]	-32	[5]	245	[5]
Long-term debt [Member] | Senior Floating [Member] | Fannie Mae [Member]	'		'		'		'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Beginning Balance	-310		-383		-955		-400
Total (Losses) Gains (Realized/Unrealized) Included in Net Loss	-15		46		-105		63
Total Gains or (Losses) Included in Other Comprehensive Income (Loss)	0	[1]	0	[1]	0	[1]	0	[1]
Purchases	0	[2]	0	[2]	0	[2]	0	[2]
Sales	0	[2]	0	[2]	0	[2]	0	[2]
Issues	0	[3]	0	[3]	-750	[3]	0	[3]
Settlements	0	[3]	0	[3]	20	[3]	0	[3]
Transfers out of Level 3	0	[4]	0	[4]	1,465	[4]	0	[4]
Transfers into Level 3	0	[4]	0	[4]	0	[4]	0	[4]
Ending Balance	-325		-337		-325		-337
Net Unrealized (Loss) Gain Included in Net Loss Related to Liabilities Still Held at period end	($15)	[5]	$46	[5]	($59)	[5]	$63	[5]
[1]	Gains (losses) included in other comprehensive income are included in “Changes in unrealized gains on available-for-sale securities, net of reclassification adjustments and taxes” in the condensed consolidated statements of operations and comprehensive income.
[2]	Purchases and sales include activity related to the consolidation and deconsolidation of assets of securitization trusts.
[3]	Issues and settlements include activity related to the consolidation and deconsolidation of liabilities of securitization trusts.
[4]	Transfers out of Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans and credit risk sharing securities issued under our Connecticut Avenue Securities series. Prices for these securities were obtained from multiple third-party vendors or dealers supported by market observable inputs. Transfers into Level 3 consisted primarily of private-label mortgage-related securities backed by Alt-A loans. Prices for these securities are based on inputs from a single source or inputs that were not readily observable.
[5]	Amount represents temporary changes in fair value. Amortization, accretion and other-than-temporary impairments are not considered unrealized and are not included in this amount.

Fair_Value_Nonrecurring_Change

Fair Value Nonrecurring Changes in Fair Value (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	$0		$0
Mortgage loans held for investment, at fair value	0		0
Total nonrecurring fair value measurements	47,967		52,939
Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	169		185
Mortgage loans held for investment, at fair value	2,649,758		2,599,667
Total nonrecurring fair value measurements	2,722,513		2,694,859
Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	492		195
Mortgage loans held for investment, at fair value	410,625		392,355
Total nonrecurring fair value measurements	432,006		415,630
Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	661		380
Mortgage loans held for investment, at fair value	3,060,383		2,992,022
Total nonrecurring fair value measurements	3,195,589		3,155,006
Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	0		0
Other assets	0		0
Total nonrecurring fair value measurements	0		0
Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	89		101
Other assets	0		0
Total nonrecurring fair value measurements	89		101
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	151		132
Other assets	113		121
Total nonrecurring fair value measurements	23,002		25,970
Fair Value, Measurements, Nonrecurring [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	240		233
Other assets	113		121
Total nonrecurring fair value measurements	23,091		26,071
Fannie Mae [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0		0
Fannie Mae [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	29,361		29,920
Fannie Mae [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	219,051		215,960
Fannie Mae [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	248,412		245,880
Consolidated Trusts [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Consolidated Trusts [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0		0
Consolidated Trusts [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	2,620,397		2,569,747
Consolidated Trusts [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	191,574		176,395
Consolidated Trusts [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	2,811,971		2,746,142
Single-Family [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Acquired property, net	0		0
Single-Family [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Acquired property, net	0		0
Single-Family [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Acquired property, net	4,300		4,041
Single-Family [Member] | Fair Value, Measurements, Nonrecurring [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Acquired property, net	4,300		4,041
Single-Family [Member] | Fannie Mae [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0	[1]	0	[1]
Single-Family [Member] | Fannie Mae [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0	[1]	0	[1]
Single-Family [Member] | Fannie Mae [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189	[1]	19,966	[1]
Single-Family [Member] | Fannie Mae [Member] | Fair Value, Measurements, Nonrecurring [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189	[1]	19,966	[1]
Single-Family [Member] | Consolidated Trusts [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0	[1]	0	[1]
Single-Family [Member] | Consolidated Trusts [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0	[1]	0	[1]
Single-Family [Member] | Consolidated Trusts [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	53	[1]	79	[1]
Single-Family [Member] | Consolidated Trusts [Member] | Fair Value, Measurements, Nonrecurring [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	53	[1]	79	[1]
Multifamily [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0		0
Acquired property, net	0		0
Multifamily [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	0		0
Acquired property, net	0		0
Multifamily [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	1,033		1,533
Acquired property, net	163		98
Multifamily [Member] | Fair Value, Measurements, Nonrecurring [Member] | Estimated Fair Value [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Mortgage loans held for investment, at fair value	1,033		1,533
Acquired property, net	$163		$98
[1]	Excludes estimated recoveries from mortgage insurance proceeds.

Fair_Value_Level_3_Valuation_I

Fair Value Level 3 Valuation Inputs (Details) (USD $)	6 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Derivatives	1,236	[1]	334	[1]
Fannie Mae [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-3,432		-1,308
Consolidated Trusts [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Long-term Debt, Fair Value	-16,420		-14,976
Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	492		195
Trading securities	2,669		2,774
Available-for-sale securities	16,810		19,012
Mortgage loans held for investment, at fair value	410,625		392,355
Total assets at fair value	432,006		415,630
Significant Unobservable Inputs (Level 3) [Member] | Fannie Mae [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	219,051		215,960
Long-term Debt, Fair Value	-940		-1,557
Significant Unobservable Inputs (Level 3) [Member] | Consolidated Trusts [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	191,574		176,395
Long-term Debt, Fair Value	-15,054		-13,362
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	151		132
Other assets	113		121
Total assets at fair value	23,002		25,970
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Appraisals [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	1		26
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Build-Up [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	39		0
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Internal Model [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	104		81
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	8		14
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Consensus without Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	112		132
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	4,300		4,041
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member] | Appraisals [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	1,370		1,077
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member] | Internal Model [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	783		1,049
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	119		118
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member] | Accepted Offers [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	854		691
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Single-Family [Member] | Walk Forwards [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	1,174		1,106
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	1,033		1,533
Acquired property, net	163		98
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member] | Appraisals [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	44		39
Acquired property, net	68		65
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	38		16
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member] | Broker Price Opinions [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	109		248
Acquired property, net	78		9
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member] | Accepted Offers [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	17		24
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Multifamily [Member] | Asset Manager Estimate [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	842		1,230
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fannie Mae [Member] | Single-Family [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189	[2]	19,966	[2]
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fannie Mae [Member] | Single-Family [Member] | Internal Model [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189		19,966
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Consolidated Trusts [Member] | Single-Family [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	53	[2]	79	[2]
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Internal Model [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	53		79
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	2,669		2,774
Available-for-sale securities	16,810		19,012
Derivatives	20		-40
Long-term Debt, Fair Value	-823		-1,473
Total assets at fair value	22,149		24,555
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	1,282		1,448
Available-for-sale securities	5,705		7,068
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Mortgage revenue bonds [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	643		565
Available-for-sale securities	4,560		5,253
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	101		99
Available-for-sale securities	2,817		2,885
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	643		618
Available-for-sale securities	3,717		3,791
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	'		50
Available-for-sale securities	'		816
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		6.90%	[3],[4]
Prepayment Speed (%)	'		0.10%	[4]
Severity (%)	'		75.00%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		6.90%	[3],[4]
Prepayment Speed (%)	'		0.10%	[4]
Severity (%)	'		75.00%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		6.90%	[3],[4]
Prepayment Speed (%)	'		0.10%	[4]
Severity (%)	'		75.00%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		0.70%	[3],[4]
Prepayment Speed (%)	'		0.20%	[4]
Severity (%)	'		43.80%	[4]
Spreads (bps)	'		1.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		7.60%	[3],[4]
Prepayment Speed (%)	'		12.50%	[4]
Severity (%)	'		98.00%	[4]
Spreads (bps)	'		3.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		5.10%	[3],[4]
Prepayment Speed (%)	'		4.10%	[4]
Severity (%)	'		79.50%	[4]
Spreads (bps)	'		2.92%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	464		539
Available-for-sale securities	1,677		1,899
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	1.03%	[4]	0.35%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	4.35%	[4]	4.40%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	3.22%	[4]	3.41%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	0.00%	[4]	0.06%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	5.93%	[4]	4.90%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	3.27%	[4]	3.10%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	101		99
Available-for-sale securities	855		610
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	4.45%	[4]	5.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	4.45%	[4]	5.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	4.45%	[4]	5.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	0.00%	[4]	5.00%	[4]
Prepayment Speed (%)	0.00%	[4]	10.00%	[4]
Severity (%)	0.00%	[4]	55.00%	[4]
Spreads (bps)	2.20%	[4]	3.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.00%	[4]	5.00%	[4]
Prepayment Speed (%)	8.80%	[4]	10.00%	[4]
Severity (%)	85.00%	[4]	55.00%	[4]
Spreads (bps)	4.45%	[4]	5.11%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	1.00%	[4]	5.00%	[4]
Prepayment Speed (%)	1.40%	[4]	10.00%	[4]
Severity (%)	8.40%	[4]	55.00%	[4]
Spreads (bps)	3.51%	[4]	4.70%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	381		148
Available-for-sale securities	812		420
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	4.20%	[3],[4]	4.00%	[3],[4]
Prepayment Speed (%)	2.20%	[4]	1.90%	[4]
Severity (%)	47.10%	[4]	42.70%	[4]
Spreads (bps)	2.48%	[4]	3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	8.80%	[3],[4]	6.90%	[3],[4]
Prepayment Speed (%)	5.10%	[4]	3.40%	[4]
Severity (%)	85.30%	[4]	77.30%	[4]
Spreads (bps)	3.00%	[4]	4.39%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	7.70%	[3],[4]	6.50%	[3],[4]
Prepayment Speed (%)	3.40%	[4]	2.20%	[4]
Severity (%)	75.50%	[4]	67.60%	[4]
Spreads (bps)	2.67%	[4]	4.19%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	2.00%	[3],[4]	2.30%	[3],[4]
Prepayment Speed (%)	0.60%	[4]	1.20%	[4]
Severity (%)	24.70%	[4]	45.20%	[4]
Spreads (bps)	1.46%	[4]	2.20%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	11.80%	[3],[4]	10.10%	[3],[4]
Prepayment Speed (%)	8.70%	[4]	7.00%	[4]
Severity (%)	95.00%	[4]	79.50%	[4]
Spreads (bps)	3.50%	[4]	5.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Discounted Cash Flow with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.30%	[3],[4]	5.10%	[3],[4]
Prepayment Speed (%)	6.10%	[4]	3.40%	[4]
Severity (%)	51.10%	[4]	60.50%	[4]
Spreads (bps)	2.43%	[4]	3.81%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Internal Model [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Derivatives	-89		-64
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Dealer Mark [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Derivatives	85		32
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Derivatives	24		-8
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member] | Agency [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	'		44	[5]
Available-for-sale securities	11	[5]	15	[5]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	119		'
Available-for-sale securities	492		65
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member] | Mortgage revenue bonds [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	179		26
Available-for-sale securities	81		31
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	1,140		1,045
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Other Valuation Technique [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	37		'
Available-for-sale securities	353		109
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	416		400
Available-for-sale securities	2,020		2,981
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	3.70%	[3],[4]	3.00%	[3],[4]
Prepayment Speed (%)	0.20%	[4]	1.40%	[4]
Severity (%)	71.70%	[4]	50.40%	[4]
Spreads (bps)	2.45%	[4]	3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	11.20%	[3],[4]	9.20%	[3],[4]
Prepayment Speed (%)	4.10%	[4]	2.20%	[4]
Severity (%)	95.00%	[4]	87.20%	[4]
Spreads (bps)	3.45%	[4]	4.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	7.80%	[3],[4]	6.40%	[3],[4]
Prepayment Speed (%)	1.50%	[4]	1.90%	[4]
Severity (%)	80.60%	[4]	74.40%	[4]
Spreads (bps)	2.73%	[4]	3.53%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	1.80%	[3],[4]	0.00%	[3],[4]
Prepayment Speed (%)	0.10%	[4]	0.30%	[4]
Severity (%)	28.00%	[4]	36.80%	[4]
Spreads (bps)	1.35%	[4]	1.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	20.60%	[3],[4]	36.80%	[3],[4]
Prepayment Speed (%)	19.80%	[4]	9.70%	[4]
Severity (%)	95.00%	[4]	100.00%	[4]
Spreads (bps)	2.45%	[4]	3.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	6.30%	[3],[4]	7.40%	[3],[4]
Prepayment Speed (%)	2.90%	[4]	2.30%	[4]
Severity (%)	84.30%	[4]	81.70%	[4]
Spreads (bps)	1.97%	[4]	3.20%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	493		483
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	3.10%	[4]	0.10%	[4]
Prepayment Speed (%)	2.00%	[4]	3.00%	[4]
Severity (%)	0.20%	[4]	65.00%	[4]
Spreads (bps)	1.95%	[4]	2.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.00%	[4]	5.00%	[4]
Prepayment Speed (%)	9.80%	[4]	11.40%	[4]
Severity (%)	85.00%	[4]	85.00%	[4]
Spreads (bps)	7.45%	[4]	9.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Other [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	4.70%	[4]	5.00%	[4]
Prepayment Speed (%)	3.70%	[4]	3.00%	[4]
Severity (%)	71.60%	[4]	84.60%	[4]
Spreads (bps)	3.36%	[4]	5.26%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	67		325
Available-for-sale securities	1,254		1,948
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	4.20%	[3],[4]	6.90%	[3],[4]
Prepayment Speed (%)	2.20%	[4]	1.90%	[4]
Severity (%)	47.10%	[4]	77.30%	[4]
Spreads (bps)	2.41%	[4]	2.98%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	4.20%	[3],[4]	10.40%	[3],[4]
Prepayment Speed (%)	2.20%	[4]	2.50%	[4]
Severity (%)	47.10%	[4]	97.80%	[4]
Spreads (bps)	2.41%	[4]	4.20%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	4.20%	[3],[4]	8.90%	[3],[4]
Prepayment Speed (%)	2.20%	[4]	2.20%	[4]
Severity (%)	47.10%	[4]	88.70%	[4]
Spreads (bps)	2.41%	[4]	3.66%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	0.90%	[3],[4]	0.10%	[3],[4]
Prepayment Speed (%)	0.00%	[4]	0.10%	[4]
Severity (%)	27.80%	[4]	7.20%	[4]
Spreads (bps)	1.70%	[4]	2.11%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	16.70%	[3],[4]	10.30%	[3],[4]
Prepayment Speed (%)	36.80%	[4]	32.90%	[4]
Severity (%)	95.00%	[4]	100.00%	[4]
Spreads (bps)	2.25%	[4]	4.04%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus with Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.20%	[3],[4]	3.50%	[3],[4]
Prepayment Speed (%)	10.10%	[4]	9.90%	[4]
Severity (%)	69.70%	[4]	62.30%	[4]
Spreads (bps)	2.20%	[4]	3.37%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	'		113
Available-for-sale securities	'		442
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		3.10%	[3],[4]
Prepayment Speed (%)	'		1.80%	[4]
Severity (%)	'		75.00%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		7.50%	[3],[4]
Prepayment Speed (%)	'		2.50%	[4]
Severity (%)	'		87.20%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		3.90%	[3],[4]
Prepayment Speed (%)	'		2.00%	[4]
Severity (%)	'		75.80%	[4]
Spreads (bps)	'		3.25%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		1.80%	[3],[4]
Prepayment Speed (%)	'		1.00%	[4]
Severity (%)	'		65.00%	[4]
Spreads (bps)	'		2.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		11.00%	[3],[4]
Prepayment Speed (%)	'		9.40%	[4]
Severity (%)	'		100.00%	[4]
Spreads (bps)	'		3.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Subprime private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		7.40%	[3],[4]
Prepayment Speed (%)	'		2.00%	[4]
Severity (%)	'		82.20%	[4]
Spreads (bps)	'		3.15%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Mortgage revenue bonds [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	2,155		1,937
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	0.00%	[4]	0.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	3.25%	[4]	4.63%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Mortgage revenue bonds [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	0.58%	[4]	1.12%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	'		60
Available-for-sale securities	454		139
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		6.00%	[3],[4]
Prepayment Speed (%)	'		4.10%	[4]
Severity (%)	'		76.10%	[4]
Spreads (bps)	'		4.14%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		10.80%	[3],[4]
Prepayment Speed (%)	'		5.40%	[4]
Severity (%)	'		92.70%	[4]
Spreads (bps)	'		4.22%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Trading securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		8.70%	[3],[4]
Prepayment Speed (%)	'		4.60%	[4]
Severity (%)	'		83.10%	[4]
Spreads (bps)	'		4.18%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	2.20%	[3],[4]	0.90%	[3],[4]
Prepayment Speed (%)	1.60%	[4]	9.30%	[4]
Severity (%)	14.20%	[4]	53.70%	[4]
Spreads (bps)	1.56%	[4]	3.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.70%	[3],[4]	6.40%	[3],[4]
Prepayment Speed (%)	20.70%	[4]	11.90%	[4]
Severity (%)	95.00%	[4]	82.60%	[4]
Spreads (bps)	3.20%	[4]	4.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor With Inputs [Member] | Alt-A private-label securities [Member] | Available-for-sale securities [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	3.90%	[3],[4]	3.90%	[3],[4]
Prepayment Speed (%)	7.10%	[4]	11.30%	[4]
Severity (%)	54.60%	[4]	68.80%	[4]
Spreads (bps)	2.39%	[4]	3.49%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus without Inputs [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	549		808
Available-for-sale securities	2,846		2,442
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus without Inputs [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	329		625
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consensus without Inputs [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	158		85
Available-for-sale securities	844		740
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor Without Inputs [Member] | Subprime private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Trading securities	198		77
Available-for-sale securities	347		322
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor Without Inputs [Member] | Mortgage revenue bonds [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	647		1,386
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor Without Inputs [Member] | Other [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	'		122
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Single Vendor Without Inputs [Member] | Alt-A private-label securities [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Available-for-sale securities	'		435
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-325		-955
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Senior Floating [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-325		-955
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Consensus with Inputs [Member] | Senior Floating [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	'		-689
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Senior Floating [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		0.20%	[4]
Prepayment Speed (%)	'		8.40%	[4]
Spreads (bps)	'		1.71%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Senior Floating [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		0.20%	[4]
Prepayment Speed (%)	'		8.40%	[4]
Spreads (bps)	'		4.38%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Senior Floating [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		0.20%	[4]
Prepayment Speed (%)	'		8.40%	[4]
Spreads (bps)	'		3.06%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Fannie Mae [Member] | Discounted Cash Flow without Inputs [Member] | Senior Floating [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-325		-266
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	2,531		2,704
Long-term Debt, Fair Value	-498		-518
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Discounted Cash Flow with Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-139		'
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Discounted Cash Flow with Inputs [Member] | Long-term debt [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	1.00%	[4]	'
Prepayment Speed (%)	0.20%	[4]	'
Severity (%)	38.40%	[4]	'
Spreads (bps)	0.64%	[4]	'
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Discounted Cash Flow with Inputs [Member] | Long-term debt [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	10.20%	[4]	'
Prepayment Speed (%)	100.00%	[4]	'
Severity (%)	95.00%	[4]	'
Spreads (bps)	5.95%	[4]	'
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Discounted Cash Flow with Inputs [Member] | Long-term debt [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	3.40%	[4]	'
Prepayment Speed (%)	23.90%	[4]	'
Severity (%)	44.80%	[4]	'
Spreads (bps)	2.09%	[4]	'
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-143		-95
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Consensus with Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	'		-116
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		1.10%	[4]
Prepayment Speed (%)	'		0.20%	[4]
Severity (%)	'		63.90%	[4]
Spreads (bps)	'		1.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		4.70%	[4]
Prepayment Speed (%)	'		16.70%	[4]
Severity (%)	'		89.50%	[4]
Spreads (bps)	'		9.50%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Consensus with Inputs [Member] | Long-term debt [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		3.20%	[4]
Prepayment Speed (%)	'		15.20%	[4]
Severity (%)	'		85.60%	[4]
Spreads (bps)	'		2.95%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Consensus without Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	-216		-227
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single Vendor Without Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Long-term Debt, Fair Value	'		-80
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	2,351		2,529
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Build-Up [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	1,634		1,828
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Build-Up [Member] | Mortgage Loans [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	0.10%	[4]	0.10%	[4]
Prepayment Speed (%)	2.80%	[4]	2.30%	[4]
Severity (%)	0.00%	[4]	0.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Build-Up [Member] | Mortgage Loans [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	97.60%	[4]	95.60%	[4]
Prepayment Speed (%)	45.70%	[4]	37.60%	[4]
Severity (%)	100.00%	[4]	100.00%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Build-Up [Member] | Mortgage Loans [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	14.70%	[4]	15.70%	[4]
Prepayment Speed (%)	17.20%	[4]	14.10%	[4]
Severity (%)	27.40%	[4]	26.60%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Discounted Cash Flow with Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	408		310
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage Loans [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	1.00%	[4]	1.20%	[4]
Prepayment Speed (%)	0.20%	[4]	1.90%	[4]
Severity (%)	38.40%	[4]	58.80%	[4]
Spreads (bps)	1.35%	[4]	1.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage Loans [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	14.60%	[4]	15.70%	[4]
Prepayment Speed (%)	17.50%	[4]	16.70%	[4]
Severity (%)	95.00%	[4]	97.70%	[4]
Spreads (bps)	5.95%	[4]	3.61%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Discounted Cash Flow with Inputs [Member] | Mortgage Loans [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	5.00%	[4]	7.00%	[4]
Prepayment Speed (%)	7.90%	[4]	7.00%	[4]
Severity (%)	56.40%	[4]	75.50%	[4]
Spreads (bps)	1.92%	[4]	2.52%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Other Valuation Technique [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	72		60
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Consensus with Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	'		112
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Consensus with Inputs [Member] | Mortgage Loans [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		1.10%	[4]
Prepayment Speed (%)	'		0.20%	[4]
Severity (%)	'		63.90%	[4]
Spreads (bps)	'		1.75%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Consensus with Inputs [Member] | Mortgage Loans [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		4.70%	[4]
Prepayment Speed (%)	'		16.70%	[4]
Severity (%)	'		89.50%	[4]
Spreads (bps)	'		9.50%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Consensus with Inputs [Member] | Mortgage Loans [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Default Rate (%)	'		3.20%	[4]
Prepayment Speed (%)	'		15.20%	[4]
Severity (%)	'		85.60%	[4]
Spreads (bps)	'		2.94%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Single-Family [Member] | Consensus without Inputs [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	237		219
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Multifamily [Member] | Build-Up [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	180		175
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Multifamily [Member] | Build-Up [Member] | Mortgage Loans [Member] | Minimum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	0.46%	[4]	0.62%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Multifamily [Member] | Build-Up [Member] | Mortgage Loans [Member] | Maximum [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	2.86%	[4]	2.43%	[4]
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member] | Consolidated Trusts [Member] | Multifamily [Member] | Build-Up [Member] | Mortgage Loans [Member] | Weighted Average [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Spreads (bps)	1.15%	[4]	1.14%	[4]
[1]	Excludes derivative assets of $28 million and $1.7 billion and derivative liabilities of $1 million and $1.1 billion recognized in our condensed consolidated balance sheets as of June 30, 2014 and December 31, 2013, respectively, that are not subject to enforceable master netting arrangements.
[2]	Excludes estimated recoveries from mortgage insurance proceeds.
[3]	Default Rate as disclosed represents the estimated beginning annualized rate of default and is used as a basis to forecast the future default rates that serve as an input for valuation.
[4]	Valuation techniques for which no unobservable inputs are disclosed generally reflect the use of third-party pricing services or dealers, and the range of unobservable inputs applied by these sources is not readily available or cannot be reasonably estimated. Where we have disclosed unobservable inputs for consensus and single vendor techniques, those inputs are based on our validations performed at the security level using discounted cash flows.
[5]	Includes Fannie Mae and Freddie Mac securities.

Fair_Value_Level_3_Valuation_N

Fair Value Level 3 Valuation - Nonrecurring (Details) (USD $)	Jun. 30, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	$492		$195
Mortgage loans held for investment, at fair value	410,625		392,355
Total assets at fair value	432,006		415,630
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	151		132
Other assets	113		121
Total assets at fair value	23,002		25,970
Fannie Mae [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	219,051		215,960
Consolidated Trusts [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Consolidated Trusts [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	191,574		176,395
Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	4,300		4,041
Single-Family [Member] | Fannie Mae [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189	[1]	19,966	[1]
Single-Family [Member] | Consolidated Trusts [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	53	[1]	79	[1]
Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	1,033		1,533
Acquired property, net	163		98
Proprietary Home Price Model and Appraisals [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Number of Acquired Properties Valuated, Percentage	76.00%		81.00%
Consensus without Inputs [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	112		132
Build-Up [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for sale, at lower of cost or fair value	39		0
Internal Model [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	104		81
Internal Model [Member] | Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	783		1,049
Internal Model [Member] | Single-Family [Member] | Fannie Mae [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	17,189		19,966
Internal Model [Member] | Single-Family [Member] | Consolidated Trusts [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	53		79
Appraisals [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	1		26
Appraisals [Member] | Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	1,370		1,077
Appraisals [Member] | Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	44		39
Acquired property, net	68		65
Walk Forwards [Member] | Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	1,174		1,106
Broker Price Opinions [Member] | Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	109		248
Acquired property, net	78		9
Asset Manager Estimate [Member] | Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	842		1,230
Other Valuation Technique [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Other assets	8		14
Other Valuation Technique [Member] | Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	119		118
Other Valuation Technique [Member] | Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Mortgage loans held for investment, at fair value	38		16
Accepted Offers [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Number of Acquired Properties Valuated, Percentage	20.00%		16.00%
Accepted Offers [Member] | Single-Family [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	854		691
Accepted Offers [Member] | Multifamily [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'
Fair Value Inputs, Quantitative Information [Line Items]	'		'
Acquired property, net	$17		$24
[1]	Excludes estimated recoveries from mortgage insurance proceeds.

Fair_Value_Fair_Value_of_Finan

Fair Value Fair Value of Financial Instruments (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Carrying Value [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	$50,434,000,000	$48,223,000,000
Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700,000,000	38,975,000,000
Trading securities	26,630,000,000	30,768,000,000
Available-for-sale securities	34,026,000,000	38,171,000,000
Mortgage loans held for sale	625,000,000	380,000,000
Mortgage loans held for investment, at fair value	3,004,161,000,000	3,025,860,000,000
Advances to lenders	4,741,000,000	3,727,000,000
Derivatives assets at fair value	1,264,000,000	2,073,000,000
Guaranty assets and buy-ups	253,000,000	267,000,000
Total financial assets	3,138,834,000,000	3,188,444,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	736,000,000	1,469,000,000
Guaranty obligations	453,000,000	485,000,000
Total financial liabilities	3,190,734,000,000	3,236,477,000,000
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	34,884,000,000	36,633,000,000
Federal funds sold and securities purchased under agreements to resell or similar arrangements	0	0
Trading securities	13,083,000,000	16,306,000,000
Available-for-sale securities	0	0
Mortgage loans held for sale	0	0
Mortgage loans held for investment, at fair value	0	0
Advances to lenders	0	0
Derivatives assets at fair value	0	0
Guaranty assets and buy-ups	0	0
Total financial assets	47,967,000,000	52,939,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	0	0
Guaranty obligations	0	0
Total financial liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	15,550,000,000	11,590,000,000
Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700,000,000	38,975,000,000
Trading securities	10,878,000,000	11,688,000,000
Available-for-sale securities	17,216,000,000	19,159,000,000
Mortgage loans held for sale	169,000,000	185,000,000
Mortgage loans held for investment, at fair value	2,649,758,000,000	2,599,667,000,000
Advances to lenders	4,220,000,000	3,165,000,000
Derivatives assets at fair value	8,022,000,000	10,430,000,000
Guaranty assets and buy-ups	0	0
Total financial assets	2,722,513,000,000	2,694,859,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	10,007,000,000	10,734,000,000
Guaranty obligations	0	0
Total financial liabilities	3,253,326,000,000	3,231,253,000,000
Significant Unobservable Inputs (Level 3) [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	0	0
Federal funds sold and securities purchased under agreements to resell or similar arrangements	0	0
Trading securities	2,669,000,000	2,774,000,000
Available-for-sale securities	16,810,000,000	19,012,000,000
Mortgage loans held for sale	492,000,000	195,000,000
Mortgage loans held for investment, at fair value	410,625,000,000	392,355,000,000
Advances to lenders	505,000,000	523,000,000
Derivatives assets at fair value	139,000,000	65,000,000
Guaranty assets and buy-ups	766,000,000	706,000,000
Total financial assets	432,006,000,000	415,630,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	119,000,000	105,000,000
Guaranty obligations	2,049,000,000	2,433,000,000
Total financial liabilities	20,006,000,000	19,611,000,000
Netting Adjustment [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	0	0
Federal funds sold and securities purchased under agreements to resell or similar arrangements	0	0
Trading securities	0	0
Available-for-sale securities	0	0
Mortgage loans held for sale	0	0
Mortgage loans held for investment, at fair value	0	0
Advances to lenders	0	0
Derivatives assets at fair value	-6,897,000,000	-8,422,000,000
Guaranty assets and buy-ups	0	0
Total financial assets	-6,897,000,000	-8,422,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	-9,390,000,000	-9,370,000,000
Guaranty obligations	0	0
Total financial liabilities	-9,390,000,000	-9,370,000,000
Estimated Fair Value [Member]	'	'
Financial assets [Abstract]	'	'
Cash and cash equivalents and restricted cash	50,434,000,000	48,223,000,000
Federal funds sold and securities purchased under agreements to resell or similar arrangements	16,700,000,000	38,975,000,000
Trading securities	26,630,000,000	30,768,000,000
Available-for-sale securities	34,026,000,000	38,171,000,000
Mortgage loans held for sale	661,000,000	380,000,000
Mortgage loans held for investment, at fair value	3,060,383,000,000	2,992,022,000,000
Advances to lenders	4,725,000,000	3,688,000,000
Derivatives assets at fair value	1,264,000,000	2,073,000,000
Guaranty assets and buy-ups	766,000,000	706,000,000
Total financial assets	3,195,589,000,000	3,155,006,000,000
Financial liabilities [Abstract]	'	'
Derivative liabilities at fair value	736,000,000	1,469,000,000
Guaranty obligations	2,049,000,000	2,433,000,000
Total financial liabilities	3,263,942,000,000	3,241,494,000,000
Fannie Mae [Member]	'	'
Financial liabilities [Abstract]	'	'
Long-term debt	3,432,000,000	1,308,000,000
Fannie Mae [Member] | Carrying Value [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	247,966,000,000	259,638,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	90,926,000,000	72,295,000,000
Long-term debt	386,609,000,000	457,139,000,000
Fannie Mae [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	0	0
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	0	0
Fannie Mae [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	29,361,000,000	29,920,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	90,935,000,000	72,304,000,000
Long-term debt	398,264,000,000	463,991,000,000
Fannie Mae [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	219,051,000,000	215,960,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	940,000,000	1,557,000,000
Fannie Mae [Member] | Netting Adjustment [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	0	0
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	0	0
Fannie Mae [Member] | Estimated Fair Value [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	248,412,000,000	245,880,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	90,935,000,000	72,304,000,000
Long-term debt	399,204,000,000	465,548,000,000
Consolidated Trusts [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	15,116,000,000	14,268,000,000
Financial liabilities [Abstract]	'	'
Long-term debt	16,420,000,000	14,976,000,000
Consolidated Trusts [Member] | Carrying Value [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	2,756,195,000,000	2,766,222,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	1,844,000,000	2,154,000,000
Long-term debt	2,710,166,000,000	2,702,935,000,000
Consolidated Trusts [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	0	0
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	0	0
Consolidated Trusts [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	2,620,397,000,000	2,569,747,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	2,754,120,000,000	2,684,224,000,000
Consolidated Trusts [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	191,574,000,000	176,395,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	1,844,000,000	2,154,000,000
Long-term debt	15,054,000,000	13,362,000,000
Consolidated Trusts [Member] | Netting Adjustment [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	0	0
Financial liabilities [Abstract]	'	'
Short-term debt	0	0
Long-term debt	0	0
Consolidated Trusts [Member] | Estimated Fair Value [Member]	'	'
Financial assets [Abstract]	'	'
Mortgage loans held for investment, at fair value	2,811,971,000,000	2,746,142,000,000
Financial liabilities [Abstract]	'	'
Short-term debt	1,844,000,000	2,154,000,000
Long-term debt	2,769,174,000,000	2,697,586,000,000
HARP loans [Member]	'	'
Financial liabilities [Abstract]	'	'
Loans Receivable Refinanced under Home Affordable Refinance Program, Fair Value Disclosure	303,600,000,000	306,900,000,000
HARP loans [Member] | Fair Value Estimation Process [Member]	'	'
Financial Instruments [Line Items]	'	'
Change In Estimated Fair Value Resulting From Change In Principal Market	$10,100,000,000	$11,500,000,000

Fair_Value_Fair_Value_Measurem

Fair Value Fair Value Measurement (Narratives) (Details) (HARP loans [Member], USD $)	Jun. 30, 2014	Dec. 31, 2013
In Billions, unless otherwise specified
Changes due to new accounting guidance or enhanced fair value estimation process [Line Items]	'	'
Loans Receivable Refinanced under Home Affordable Refinance Program, Fair Value Disclosure	$303.60	$306.90
Fair Value Estimation Process [Member]	'	'
Changes due to new accounting guidance or enhanced fair value estimation process [Line Items]	'	'
Changes in estimated fair value	$10.10	$11.50

Fair_Value_FV_Realized_and_Unr

Fair Value FV Realized and Unrealized Gains and Losses (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Total realized and unrealized gains (losses) included in net income	$703	$38	$835	$283
Net unrealized gains related to Level 3 assets and liabilities still held at period end	417	3	531	135
Interest Income [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Total realized and unrealized gains (losses) included in net income	70	70	140	125
Net unrealized gains related to Level 3 assets and liabilities still held at period end	0	0	0	0
Fair Value Gains, net [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Total realized and unrealized gains (losses) included in net income	329	-31	435	161
Net unrealized gains related to Level 3 assets and liabilities still held at period end	417	3	531	135
Net Other-than-Temporary Impairments [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Total realized and unrealized gains (losses) included in net income	-19	-4	-64	-9
Net unrealized gains related to Level 3 assets and liabilities still held at period end	0	0	0	0
Other [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Total realized and unrealized gains (losses) included in net income	323	3	324	6
Net unrealized gains related to Level 3 assets and liabilities still held at period end	$0	$0	$0	$0

Fair_Value_Fair_Value_Option_D

Fair Value Fair Value Option (Details) (USD $)	6 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Fair value of nonaccrual loans	204		196
Difference between unpaid principal balance and the fair value of nonaccrual loans	67		74
Fair value of loans that are 90 days past due	276		288
Difference between unpaid principal balance and the fair value of these 90 days or more days past due loans	64		75
Consolidated Trusts [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Mortgage loans held for investment, at fair value	15,116		14,268
Long-term debt, fair value	16,420		14,976
Fannie Mae [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Long-term debt, fair value	3,432		1,308
Interest-only debt instruments [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Long-term debt, fair value	74		85
Loans [Member] | Consolidated Trusts [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Mortgage loans held for investment, at fair value	15,116	[1]	14,268	[1]
Loans, unpaid principal balance	14,732	[1]	14,440	[1]
Long-term debt [Member] | Consolidated Trusts [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Long-term debt, fair value	16,420	[2]	14,976	[2]
Long-term debt, unpaid principal balance	15,086	[2]	13,988	[2]
Long-term debt [Member] | Fannie Mae [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Long-term debt, fair value	3,432		1,308
Long-term debt, unpaid principal balance	3,239		1,290
Single-Family [Member] | Minimum [Member]	'		'
Fair Value, Option, Quantitative Disclosures [Line Items]	'		'
Serious delinquency, days past due	'90 days		'90 days
[1]	Includes nonaccrual loans with a fair value of $204 million and $196 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these nonaccrual loans as of June 30, 2014 and December 31, 2013 was $67 million and $74 million, respectively. Includes loans that are 90 days or more past due with a fair value of $276 million and $288 million as of June 30, 2014 and December 31, 2013, respectively. The difference between unpaid principal balance and the fair value of these 90 or more days past due loans as of June 30, 2014 and December 31, 2013 was $64 million and $75 million, respectively.
[2]	Includes interest-only debt instruments with no unpaid principal balance and a fair value of $74 million and $85 million as of June 30, 2014 and December 31, 2013, respectively.

Fair_Value_Changes_in_FV_under

Fair Value Changes in FV under the FV Option (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'	'	'
Changes in instrument-specific credit risk	($60)	$68	($102)	($2)
Other changes in fair value	150	-210	157	-301
Fair value (losses) gains, net	90	-142	55	-303
Loans [Member]	'	'	'	'
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'	'	'
Changes in instrument-specific credit risk - Loans	16	66	25	1
Other changes in fair value	371	-549	494	-706
Fair value (losses) gains, net	387	-483	519	-705
Long-term debt [Member]	'	'	'	'
Fair Value, Option, Quantitative Disclosures [Line Items]	'	'	'	'
Changes in instrument-specific credit risk - Long-Term Debt	-76	2	-127	-3
Other changes in fair value	-221	339	-337	405
Fair value (losses) gains, net	($297)	$341	($464)	$402

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (Pending Litigation [Member], USD $)

12 Months Ended

9 Months Ended

0 Months Ended

1 Months Ended

In Billions, unless otherwise specified

Dec. 31, 2008

Feb. 25, 2010

Oct. 22, 2012

Mar. 02, 2012

Aug. 30, 2012

Jul. 30, 2008

Dec. 31, 2010

Sep. 30, 2010

Dec. 31, 2010

Sep. 30, 2010

31-May-08

Dec. 31, 2007

2008 Class Action Lawsuits and Related Proceedings [Member]

Individual Securities Actions [Member]

In re 2008 Fannie Mae ERISA Litigation [Member]

In re 2008 Fannie Mae ERISA Litigation [Member]

Comprehensive Investment Services v. Mudd, et al. [Member]

Housing Trust Fund [Member]

Unasserted Claim [Member]

Unasserted Claim [Member]

Unasserted Claim [Member]

Unasserted Claim [Member]

Series T Preferred Stock [Member]

Series S Preferred Stock [Member]

cases

cases

defendants

defendants

defendants

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Comprehensive Investment Services v. Mudd, et al. [Member]

Smith v. Fannie Mae, et al. [Member]

In re Fannie Mae Securities Litigation [Member]

In re Fannie Mae Securities Litigation [Member]

In re Fannie Mae Securities Litigation [Member]

In re Fannie Mae Securities Litigation [Member]

Loss Contingencies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Damages claimed to plaintiffs under various scenarios

'

'

'

'

'

'

$2.20

$2.20

$8.60

$8.60

'

'

Number of lawsuits that Fannie Mae is a defendant

2

2

'

'

'

'

'

'

'

'

'

'

Number of current Board members added as defendants

'

'

'

2

'

'

'

'

'

'

'

'

Number of former and current directors and officers dismissed from the action

'

'

7

'

2

'

'

'

'

'

'

'

Preferred stock offering amount

'

'

'

'

'

'

'

'

'

'

$2

$7

Preferred stock, annual dividend rate

'

'

'

'

'

'

'

'

'

'

8.25%

7.75%

Basis points of each dollar of unpaid principal balance

'

'

'

'

'

0.04%

'

'

'

'

'

'

Percentage of the funds set aside as required by the Federal Housing Finance Regulatory Reform Act of 2008 that should be allocated to the Housing Trust Fund

'

'

'

'

'

65.00%

'

'

'

'

'

'

Percentage of the funds set aside as required by the Federal Housing Finance Regulatory Reform Act of 2008 that should be allocated to the Capital Magnet Fund

'

'

'

'

'

35.00%

'

'

'

'

'

'