Condensed Consolidated Statements of Income - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019		Jun. 30, 2020		Jun. 30, 2019
Interest income
Credit card loans		$ 2,173	$ 2,396		$ 4,589		$ 4,758
Other loans		439	460		923		917
Investment securities		55	39		113		67
Other interest income		5	82		29		172
Total interest income		2,672	2,977		5,654		5,914
Interest expense
Deposits		340	401		713		787
Long-term borrowings		142	244		353		490
Total interest expense		482	645		1,066		1,277
Net interest income		2,190	2,332		4,588		4,637
Provision for credit losses	[1]	2,046	787	[2]	3,853	[3]	1,596	[2],[3]
Net interest income after provision for credit losses		144	1,545		735		3,041
Other income
Discount and interchange revenue, net		237	299		453		530
Protection products revenue		44	49		91		98
Loan fee income		85	102		204		206
Transaction processing revenue		49	48		93		94
Gains on equity investments		43	0		79		0
Other income		14	22		42		50
Total other income		472	520		962		978
Other expense
Employee compensation and benefits		452	427		919		852
Marketing and business development		129	224		360		419
Information processing and communications		117	101		231		200
Professional fees		181	183		374		350
Premises and equipment		27	26		57		54
Other expense		171	117		295		227
Total other expense		1,077	1,078		2,236		2,102
(Loss) income before income taxes		(461)	987		(539)		1,917
Income tax (benefit) expense		(93)	234		(110)		438
Net (loss) income		(368)	753		(429)		1,479
Net (loss) income allocated to common stockholders		$ (369)	$ 747		$ (446)		$ 1,452
Basic (loss) earnings per common share		$ (1.20)	$ 2.32		$ (1.45)		$ 4.46
Diluted (loss) earnings per common share		$ (1.20)	$ 2.32		$ (1.45)		$ 4.46

[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.