Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Assets:
Restricted cash (includes $22,642 and $31,536, related to consolidated trusts)	$ 27,321	$ 36,953
Investments in securities:
Trading, at fair value (includes $1,066 and $1,277, respectively, pledged as collateral )	1,066	1,277
Available-for-sale, at fair value (includes $113 and $107, respectively, related to consolidated trusts)	7,721	8,363
Accrued interest receivable (includes $7,089 and $7,064, respectively, related to consolidated trusts)	7,704	7,737
Mortgage loans:
Total loans held for investment (includes $11,683 and $12,057, respectively, at fair value)	11,683	12,057
Liabilities:
Accrued interest payable (includes $8,311 and $8,285, respectively, related to consolidated trusts)	9,588	9,431
Other liabilities (includes $336 and $390, respectively, related to consolidated trusts)	$ 9,133	$ 10,150
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, 1,308,762,703 shares issued	1,308,762,703	1,308,762,703
Common stock, 1,158,087,567 shares outstanding	1,158,087,567	1,158,082,750
Treasury stock, at cost, 150,675,136 shares	150,675,136	150,679,953
Consolidated Trusts [Member]
Assets:
Restricted cash (includes $22,642 and $31,536, related to consolidated trusts)	$ 22,642	$ 31,536
Investments in securities:
Available-for-sale, at fair value (includes $113 and $107, respectively, related to consolidated trusts)	113	107
Accrued interest receivable (includes $7,089 and $7,064, respectively, related to consolidated trusts)	7,089	7,064
Liabilities:
Accrued interest payable (includes $8,311 and $8,285, respectively, related to consolidated trusts)	8,311	8,285
Debt (includes $9,162 and $9,582, respectively, of debt of Fannie Mae at fair value and $36,372 and $36,524, respectively, of debt of consolidated trusts, at fair value)	36,372	36,524
Other liabilities (includes $336 and $390, respectively, related to consolidated trusts)	336	390
Fannie Mae [Member]
Liabilities:
Debt (includes $9,162 and $9,582, respectively, of debt of Fannie Mae at fair value and $36,372 and $36,524, respectively, of debt of consolidated trusts, at fair value)	$ 9,162	$ 9,582