Securities Available for Sale (Tables)

9 Months Ended

Sep. 30, 2015

Schedule of Available-for-sale Securities [Line Items]

Securities Portfolio Composition

	September 30, 2015
(Dollars in millions)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. Treasury securities		$3,020		$45		$—		$3,065
Federal agency securities	408		13		1		420
U.S. states and political subdivisions	167		7		—		174
MBS - agency	22,452		511		58		22,905
MBS - private	100		2		—		102
ABS	13		2		—		15
Corporate and other debt securities	36		2		—		38
Other equity securities 1	551		1		1		551
Total securities AFS		$26,747		$583		$60		$27,270
	December 31, 2014
(Dollars in millions)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. Treasury securities		$1,913		$9		$1		$1,921
Federal agency securities	471		15		2		484
U.S. states and political subdivisions	200		9		—		209
MBS - agency	22,573		558		83		23,048
MBS - private	122		2		1		123
ABS	19		2		—		21
Corporate and other debt securities	38		3		—		41
Other equity securities 1	921		2		—		923
Total securities AFS		$26,257		$600		$87		$26,770

¹ At September 30, 2015, the fair value of other equity securities was comprised of the following: $32 million of FHLB of Atlanta stock, $402 million of Federal Reserve Bank of Atlanta stock, $111 million of mutual fund investments, and $6 million of other. At December 31, 2014, the fair value of other equity securities was comprised of the following: $376 million of FHLB of Atlanta stock, $402 million of Federal Reserve Bank of Atlanta stock, $138 million of mutual fund investments, and $7 million of other.

Investment Income [Table Text Block]

	Three Months Ended September 30				Nine Months Ended September 30
(Dollars in millions)	2015		2014		2015		2014
Taxable interest		$143		$142		$397		$421
Tax-exempt interest	2		2		5		8
Dividends	8		9		28		27
Total interest and dividends		$153		$153		$430		$456

Amortized Cost and Fair Value of Investments in Debt Securities by Estimated Average Life

	Distribution of Maturities
(Dollars in millions)	1 Year or Less			1-5 Years			5-10 Years			After 10 Years			Total
Amortized Cost:
U.S. Treasury securities		$25			$921			$2,074			$—			$3,020
Federal agency securities	159			109			14			126			408
U.S. states and political subdivisions	38			13			101			15			167
MBS - agency	2,462			11,098			3,756			5,136			22,452
MBS - private	3			89			8			—			100
ABS	—			12			1			—			13
Corporate and other debt securities	—			36			—			—			36
Total debt securities AFS		$2,687			$12,278			$5,954			$5,277			$26,196
Fair Value:
U.S. Treasury securities		$25			$931			$2,109			$—			$3,065
Federal agency securities	163			116			14			127			420
U.S. states and political subdivisions	39			13			106			16			174
MBS - agency	2,605			11,391			3,772			5,137			22,905
MBS - private	3			91			8			—			102
ABS	—			13			2			—			15
Corporate and other debt securities	—			38			—			—			38
Total debt securities AFS		$2,835			$12,593			$6,011			$5,280			$26,719
Weighted average yield 1	2.35		%	2.41		%	2.57		%	2.80		%	2.52		%

¹ Weighted average yields are based on amortized cost and presented on an FTE basis.

Securities in a Continuous Unrealized Loss Position

	September 30, 2015
	Less than twelve months				Twelve months or longer				Total
(Dollars in millions)	Fair Value		Unrealized Losses 2		Fair Value		Unrealized Losses 2		Fair Value		Unrealized Losses 2
Temporarily impaired securities AFS:
Federal agency securities		$33		$—		$35		$1		$68		$1
MBS - agency	3,996		35		982		23		4,978		58
ABS	—		—		9		—		9		—
Other equity securities	4		1		—		—		4		1
Total temporarily impaired securities AFS	4,033		36		1,026		24		5,059		60
OTTI securities AFS 1:
Total OTTI securities AFS	—		—		—		—		—		—
Total impaired securities AFS		$4,033		$36		$1,026		$24		$5,059		$60

	December 31, 2014
	Less than twelve months				Twelve months or longer				Total
(Dollars in millions)	Fair Value		Unrealized  Losses 2		Fair Value		Unrealized Losses 2		Fair Value		Unrealized  Losses 2
Temporarily impaired securities AFS:
U.S. Treasury securities		$150		$1		$—		$—		$150		$1
Federal agency securities	20		—		132		2		152		2
MBS - agency	2,347		6		4,911		77		7,258		83
ABS	—		—		14		—		14		—
Total temporarily impaired securities AFS	2,517		7		5,057		79		7,574		86
OTTI securities AFS 1:
MBS - private	69		1		—		—		69		1
Total OTTI securities AFS	69		1		—		—		69		1
Total impaired securities AFS		$2,586		$8		$5,057		$79		$7,643		$87

¹ Includes OTTI securities AFS for which credit losses have been recorded in earnings in current or prior periods.

² Unrealized losses less than $0.5 million are presented as zero within the table.