Business Segments - Business Segment Results (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Noninterest income	$ 2,381	$ 2,525
Other intangibles	38	42
Total noninterest expense	3,379	3,316
Provision for credit losses	(827)	993
Net income	2,285	1,179
Net (income) loss attributable to noncontrolling interests	(5)	(8)
Net income attributable to U.S. Bancorp	2,280	1,171
Corporate and Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	666	784
Noninterest income	259	271
Total net revenue	925	1,055
Noninterest expense	406	443
Total noninterest expense	406	443
Income before provision and income taxes	519	612
Provision for credit losses	(40)	424
Income before income taxes	559	188
Income taxes and taxable-equivalent adjustment	140	47
Net income	419	141
Net income attributable to U.S. Bancorp	419	141
Loans	94,872	103,368
Other earning assets	4,308	4,555
Goodwill	1,647	1,647
Other intangible assets	5	7
Assets	107,022	115,308
Noninterest-bearing deposits	51,020	29,370
Interest-bearing deposits	67,750	80,657
Total deposits	118,770	110,027
Total U.S. Bancorp shareholders' equity	13,074	14,182
Consumer and Business Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	1,625	1,531
Noninterest income	617	757
Total net revenue	2,242	2,288
Noninterest expense	1,388	1,336
Other intangibles	3	4
Total noninterest expense	1,391	1,340
Income before provision and income taxes	851	948
Provision for credit losses	(44)	123
Income before income taxes	895	825
Income taxes and taxable-equivalent adjustment	224	206
Net income	671	619
Net income attributable to U.S. Bancorp	671	619
Loans	153,177	146,718
Other earning assets	10,203	4,967
Goodwill	3,475	3,574
Other intangible assets	2,491	2,411
Assets	175,541	161,886
Noninterest-bearing deposits	39,186	27,866
Interest-bearing deposits	166,876	133,718
Total deposits	206,062	161,584
Total U.S. Bancorp shareholders' equity	13,453	13,422
Wealth Management and Investment Services [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	204	284
Noninterest income	492	466
Total net revenue	696	750
Noninterest expense	459	449
Other intangibles	2	3
Total noninterest expense	461	452
Income before provision and income taxes	235	298
Provision for credit losses	7	23
Income before income taxes	228	275
Income taxes and taxable-equivalent adjustment	57	69
Net income	171	206
Net income attributable to U.S. Bancorp	171	206
Loans	12,443	10,608
Other earning assets	279	281
Goodwill	1,619	1,617
Other intangible assets	42	44
Assets	15,662	13,950
Noninterest-bearing deposits	20,277	13,232
Interest-bearing deposits	71,629	68,842
Total deposits	91,906	82,074
Total U.S. Bancorp shareholders' equity	2,634	2,571
Payments Services [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	628	661
Noninterest income	785	794
Total net revenue	1,413	1,455
Noninterest expense	782	754
Other intangibles	33	35
Total noninterest expense	815	789
Income before provision and income taxes	598	666
Provision for credit losses	(41)	262
Income before income taxes	639	404
Income taxes and taxable-equivalent adjustment	160	101
Net income	479	303
Net income attributable to U.S. Bancorp	479	303
Loans	29,630	33,688
Other earning assets	5	6
Goodwill	3,173	2,856
Other intangible assets	544	557
Assets	35,095	38,285
Noninterest-bearing deposits	5,264	1,471
Interest-bearing deposits	132	114
Total deposits	5,396	1,585
Total U.S. Bancorp shareholders' equity	7,480	7,619
Treasury and Corporate Support [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	(34)	(13)
Noninterest income	228	237
Total net revenue	194	224
Noninterest expense	306	292
Total noninterest expense	306	292
Income before provision and income taxes	(112)	(68)
Provision for credit losses	(709)	161
Income before income taxes	597	(229)
Income taxes and taxable-equivalent adjustment	52	(139)
Net income	545	(90)
Net (income) loss attributable to noncontrolling interests	(5)	(8)
Net income attributable to U.S. Bancorp	540	(98)
Loans	3,867	3,275
Other earning assets	188,927	140,256
Assets	215,414	165,378
Noninterest-bearing deposits	2,605	2,203
Interest-bearing deposits	1,625	5,331
Total deposits	4,230	7,534
Total U.S. Bancorp shareholders' equity	16,088	13,352
Consolidated Company [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	3,089	3,247
Noninterest income	2,381	2,525
Total net revenue	5,470	5,772
Noninterest expense	3,341	3,274
Other intangibles	38	42
Total noninterest expense	3,379	3,316
Income before provision and income taxes	2,091	2,456
Provision for credit losses	(827)	993
Income before income taxes	2,918	1,463
Income taxes and taxable-equivalent adjustment	633	284
Net income	2,285	1,179
Net (income) loss attributable to noncontrolling interests	(5)	(8)
Net income attributable to U.S. Bancorp	2,280	1,171
Loans	293,989	297,657
Other earning assets	203,722	150,065
Goodwill	9,914	9,694
Other intangible assets	3,082	3,019
Assets	548,734	494,807
Noninterest-bearing deposits	118,352	74,142
Interest-bearing deposits	308,012	288,662
Total deposits	426,364	362,804
Total U.S. Bancorp shareholders' equity	$ 52,729	$ 51,146