Securities (Tables)

3 Months Ended

Mar. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Summary of AFS Securities

The following tables summarize AFS and HTM securities:

March 31, 2019 (Dollars in millions)	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
AFS securities:
U.S. Treasury	$	1,920	$	1	$	43	$	1,878
GSE	238		1		6		233
Agency MBS	23,450		65		468		23,047
States and political subdivisions	607		31		12		626
Non-agency MBS	313		184		—		497
Other	34		—		—		34
Total AFS securities	$	26,562	$	282	$	529	$	26,315
HTM securities:
U.S. Treasury	$	1,099	$	—	$	2	$	1,097
GSE	2,199		6		15		2,190
Agency MBS	16,792		25		223		16,594
States and political subdivisions	4		—		—		4
Other	1		—		—		1
Total HTM securities	$	20,095	$	31	$	240	$	19,886
December 31, 2018 (Dollars in millions)	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
AFS securities:
U.S. Treasury	$	3,503	$	22	$	84	$	3,441
GSE	209		—		9		200
Agency MBS	20,927		15		787		20,155
States and political subdivisions	694		25		18		701
Non-agency MBS	321		184		—		505
Other	35		1		—		36
Total AFS securities	$	25,689	$	247	$	898	$	25,038
HTM securities:
U.S. Treasury	$	1,099	$	—	$	6	$	1,093
GSE	2,199		4		43		2,160
Agency MBS	17,248		27		487		16,788
States and political subdivisions	5		—		—		5
Other	1		—		—		1
Total HTM securities	$	20,552	$	31	$	536	$	20,047

Summary of HTM Securities

The following tables summarize AFS and HTM securities:

March 31, 2019 (Dollars in millions)	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
AFS securities:
U.S. Treasury	$	1,920	$	1	$	43	$	1,878
GSE	238		1		6		233
Agency MBS	23,450		65		468		23,047
States and political subdivisions	607		31		12		626
Non-agency MBS	313		184		—		497
Other	34		—		—		34
Total AFS securities	$	26,562	$	282	$	529	$	26,315
HTM securities:
U.S. Treasury	$	1,099	$	—	$	2	$	1,097
GSE	2,199		6		15		2,190
Agency MBS	16,792		25		223		16,594
States and political subdivisions	4		—		—		4
Other	1		—		—		1
Total HTM securities	$	20,095	$	31	$	240	$	19,886
December 31, 2018 (Dollars in millions)	Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses
AFS securities:
U.S. Treasury	$	3,503	$	22	$	84	$	3,441
GSE	209		—		9		200
Agency MBS	20,927		15		787		20,155
States and political subdivisions	694		25		18		701
Non-agency MBS	321		184		—		505
Other	35		1		—		36
Total AFS securities	$	25,689	$	247	$	898	$	25,038
HTM securities:
U.S. Treasury	$	1,099	$	—	$	6	$	1,093
GSE	2,199		4		43		2,160
Agency MBS	17,248		27		487		16,788
States and political subdivisions	5		—		—		5
Other	1		—		—		1
Total HTM securities	$	20,552	$	31	$	536	$	20,047

Schedule of Amortized Cost and Estimated Fair Value by Contractual Maturity

The amortized cost and estimated fair value of the securities portfolio by contractual maturity are shown in the following table. The expected life of MBS may differ from contractual maturities because borrowers have the right to prepay the underlying mortgage loans.

	AFS				HTM
March 31, 2019 (Dollars in millions)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in one year or less	$	285	$	285	$	1	$	1
Due after one year through five years	1,674		1,631		3,300		3,289
Due after five years through ten years	502		503		597		591
Due after ten years	24,101		23,896		16,197		16,005
Total debt securities	$	26,562	$	26,315	$	20,095	$	19,886

Schedule of Fair Values and Gross Unrealized Losses

The following tables present the fair values and gross unrealized losses of investments based on the length of time that individual securities have been in a continuous unrealized loss position:

	Less than 12 months				12 months or more				Total
March 31, 2019 (Dollars in millions)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
AFS securities:
U.S. Treasury	$	49	$	—	$	1,442	$	43	$	1,491	$	43
GSE	12		—		179		6		191		6
Agency MBS	1,165		2		16,679		466		17,844		468
States and political subdivisions	44		—		241		12		285		12
Total	$	1,270	$	2	$	18,541	$	527	$	19,811	$	529
HTM securities:
U.S. Treasury	$	400	$	—	$	496	$	2	$	896	$	2
GSE	—		—		1,768		15		1,768		15
Agency MBS	1,121		5		13,748		218		14,869		223
Total	$	1,521	$	5	$	16,012	$	235	$	17,533	$	240
	Less than 12 months				12 months or more				Total
December 31, 2018 (Dollars in millions)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
AFS securities:
U.S. Treasury	$	111	$	—	$	2,121	$	84	$	2,232	$	84
GSE	3		—		176		9		179		9
Agency MBS	322		2		18,478		785		18,800		787
States and political subdivisions	100		1		288		17		388		18
Total	$	536	$	3	$	21,063	$	895	$	21,599	$	898
HTM securities:
U.S. Treasury	$	698	$	3	$	395	$	3	$	1,093	$	6
GSE	—		—		1,749		43		1,749		43
Agency MBS	264		3		14,976		484		15,240		487
Total	$	962	$	6	$	17,120	$	530	$	18,082	$	536