Summary of Significant Accounting Policies Narratives(Details) (USD $)	0 Months Ended	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2014		Mar. 31, 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	60 days
Payments of cash dividends on senior preferred stock to Treasury	$ 7,191,000,000	$ 7,191,000,000		$ 4,224,000,000
Expected undeclared dividends payable on senior preferred stock for the next quarter		5,700,000,000
Deficit of core capital over statutory minimum capital requirement	138,000,000,000	138,000,000,000				137,300,000,000
Home Affordable Modification Program administrative expense reimbursements from Treasury and Freddie Mac		17,000,000		26,000,000
Income Taxes Paid		425,000,000		0
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees		322,000,000		186,000,000
Fee and other income		4,355,000,000		568,000,000
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
Initial aggregate liquidation preference of senior preferred stock held by US Treasury	1,000,000,000	1,000,000,000
Aggregate liquidation preference of senior preferred stock	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
Percentage of common shares attributable to warrants issued to US Treasury as percentage to total diluted common shares	79.90%	79.90%
Income Taxes Paid		425,000,000
Percentage of initial principal loss US Treasury will bear for Temporary Credit and Liquidity Facilities and New Issue Bond Programs	35.00%	35.00%
Loss of principal or interest under Treasury's Temporary Credit and Liquidity Facility and New Issue Bond Programs	0	0
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees		322,000,000	[1]	186,000,000	[1],[2]
US Treasury [Member] | Temporary Credit and Liquidity Facilities Program [Member]
Related Parties [Line Items]
Principal and interest outstanding	641,000,000	641,000,000				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				4,500,000,000
Freddie Mac [Member] | Freddie Mac [Member]
Related Parties [Line Items]
Fair value of mortgage-backed securities	8,200,000,000	8,200,000,000				8,700,000,000
Investment income, interest		78,000,000		111,000,000
Federal Housing Finance Agency [Member]
Related Parties [Line Items]
FHFA assessment fees		28,000,000		28,000,000
Single-Family [Member] | US Treasury [Member]
Related Parties [Line Items]
Temporary Payroll Tax Cut Continuation Act of 2011 (“TCCA”) fees		322,000,000	[1]	186,000,000	[1],[2]
Temporary Payroll Tax Cut related guaranty fee paid to US Treasury		306,000,000
Mortgage Backed Private Label Securities and Repurchase Request Resolution Agreement [Member]
Related Parties [Line Items]
Fee and other income		$ 4,100,000,000

[1] Includes the impact of the 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.