Condensed Consolidated Statements of Income - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Interest income
Credit card loans		$ 2,416	$ 2,362
Other loans		484	457
Investment securities		58	28
Other interest income		24	90
Total interest income		2,982	2,937
Interest expense
Deposits		373	386
Long-term borrowings		211	246
Total interest expense		584	632
Net interest income		2,398	2,305
Provision for credit losses	[1],[2]	1,807	809	[3]
Net interest income after provision for credit losses		591	1,496
Other income
Discount and interchange revenue, net		216	231
Protection products revenue		47	49
Loan fee income		119	104
Transaction processing revenue		44	46
Gains on equity investments		36	0
Other income		28	28
Total other income		490	458
Other expense
Employee compensation and benefits		467	425
Marketing and business development		231	195
Information processing and communications		114	99
Professional fees		193	167
Premises and equipment		30	28
Other expense		124	110
Total other expense		1,159	1,024
(Loss) income before income taxes		(78)	930
Income tax (benefit) expense		(17)	204
Net (loss) income		(61)	726
Net (loss) income allocated to common stockholders		$ (78)	$ 705
Basic earnings (loss) per common share (in dollars per share)		$ (0.25)	$ 2.15
Diluted earnings (loss) per common share (in dollars per share)		$ (0.25)	$ 2.15

[1] Prior to adoption of ASU No. 2016-13 on January 1, 2020, credit losses were estimated using the incurred loss approach.

[2] Prior to adoption of ASU No. 2016-13 on January 1, 2020, credit losses were estimated using the incurred loss approach.

[3] Prior to adoption of ASU No. 2016-13 on January 1, 2020, credit losses were estimated using the incurred loss approach.