Investments in Securities (Tables)

3 Months Ended

Mar. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Investments In Trading Securities [Table Text Block]

The following table displays our investments in trading securities.



	As of
	March 31, 2018			December 31, 2017
	(Dollars in millions)
Mortgage-related securities:
Fannie Mae⁽¹⁾		$	1,739		$	3,876
Other agency		2,347			1,118
Alt-A and subprime private-label securities⁽¹⁾		2,745			453
Commercial mortgage-backed securities (“CMBS”)		8			9
Mortgage revenue bonds		1			1
Total mortgage-related securities		6,840			5,457
Non-mortgage-related securities:
U.S. Treasury securities		33,160			29,222
Other securities		97			—
Total non-mortgage-related securities		33,257			29,222
Total trading securities		$	40,097		$	34,679

__________


⁽¹⁾	The increase in Alt-A and subprime private-label securities and the corresponding decrease in Fannie Mae securities from December 31, 2017 to March 31, 2018 was due to the dissolution of a Fannie Mae-wrapped private-label securities trust during the period.

Schedule of Trading Securities Gains (Losses), Net [Table Text Block]

The following table displays information about our net trading gains.



	For the Three Months Ended March 31,


	2018		2017
	(Dollars in millions)
Net trading gains	$	98	$	68
Net trading gains recognized in the period related to securities still held at period end	76		77

Schedule of Realized Gain (Loss) [Table Text Block]

The following table displays the gross realized gains and proceeds on sales of AFS securities.



	For the Three Months
	Ended March 31,
	2018		2017
	(Dollars in millions)
Gross realized gains	$	363	$	3
Total proceeds (excludes initial sale of securities from new portfolio securitizations)	635		95

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.



	As of March 31, 2018
	Total Amortized Cost⁽¹⁾			Gross Unrealized Gains			Gross Unrealized Losses⁽²⁾				Total Fair Value
	(Dollars in millions)
Fannie Mae		$	1,940		$	83		$	(37	)	$	1,986
Other agency		305			22			—			327
Alt-A and subprime private-label securities		376			295			—			671
CMBS		5			—			—			5
Mortgage revenue bonds		536			14			(11		)	539
Other mortgage-related securities		346			14			—			360
Total		$	3,508		$	428		$	(48	)	$	3,888



	As of December 31, 2017
	Total Amortized Cost⁽¹⁾			Gross Unrealized Gains			Gross Unrealized Losses⁽²⁾				Total Fair Value
	(Dollars in millions)
Fannie Mae		$	2,044		$	102		$	(27	)	$	2,119
Other agency		332			25			—			357
Alt-A and subprime private-label securities		662			652			—			1,314
CMBS		15			—			—			15
Mortgage revenue bonds		655			20			(4		)	671
Other mortgage-related securities		350			17			—			367
Total		$	4,058		$	816		$	(31	)	$	4,843

__________


⁽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 “Investment gains (losses), net” in our condensed consolidated statements of operations and comprehensive income.


⁽²⁾	Represents the gross unrealized losses on securities for which we have not recognized OTTI, as well as the noncredit component of OTTI and cumulative changes in fair value of securities for which we previously recognized the credit component of OTTI in “Accumulated other comprehensive income” in our condensed consolidated balance sheets.

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.



	As of March 31, 2018
	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		$	(5	)	$	157		$	(32	)	$	425
Mortgage revenue bonds		(8		)	45			(3		)	3
Total		$	(13	)	$	202		$	(35	)	$	428

	As of December 31, 2017
	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		$	(1	)	$	134		$	(26	)	$	461
Mortgage revenue bonds		—			—			(4		)	3
Total		$	(1	)	$	134		$	(30	)	$	464

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. 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 March 31, 2018
	Total Amortized Cost			Total Fair Value		One Year or Less					After One Year Through Five Years					After Five Years Through Ten Years					After Ten Years
	Total Amortized Cost			Total Fair Value		Amortized Cost			Fair Value		Amortized Cost			Fair Value		Amortized Cost			Fair Value		Amortized Cost			Fair Value
	(Dollars in millions)
Fannie Mae		$	1,940	$	1,986		$	1	$	1		$	11	$	11		$	82	$	87		$	1,846	$	1,887
Other agency		305		327			1		1			11		11			53		57			240		258
Alt-A and subprime private-label securities		376		671			—		—			—		—			—		—			376		671
CMBS		5		5			5		5			—		—			—		—			—		—
Mortgage revenue bonds		536		539			3		3			36		36			65		67			432		433
Other mortgage-related securities		346		360			—		—			—		—			5		5			341		355
Total		$	3,508	$	3,888		$	10	$	10		$	58	$	58		$	205	$	216		$	3,235	$	3,604