Business Segments - Business Segment Results (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Securities gains (losses), net	$ 50	$ 5
Other intangibles	42	40
Total noninterest expense	3,316	3,087
Provision for credit losses	993	377
Net income	1,179	1,708
Net (income) loss attributable to noncontrolling interests	(8)	(9)
Net income attributable to U.S. Bancorp	1,171	1,699
Corporate and Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	797	778
Noninterest income	274	208
Total net revenue	1,071	986
Noninterest expense	429	420
Other intangibles		1
Total noninterest expense	429	421
Income before provision and income taxes	642	565
Provision for credit losses	425	23
Income before income taxes	217	542
Income taxes and taxable-equivalent adjustment	54	136
Net income	163	406
Net income attributable to U.S. Bancorp	163	406
Loans	103,397	98,702
Other earning assets	4,555	3,168
Goodwill	1,647	1,647
Other intangible assets	7	9
Assets	115,404	107,338
Noninterest-bearing deposits	29,329	30,211
Interest-bearing Deposits	80,704	71,223
Total deposits	110,033	101,434
Total U.S. Bancorp shareholders' equity	15,815	15,346
Consumer and Business Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	1,541	1,581
Noninterest income	757	535
Total net revenue	2,298	2,116
Noninterest expense	1,344	1,266
Other intangibles	4	5
Total noninterest expense	1,348	1,271
Income before provision and income taxes	950	845
Provision for credit losses	123	70
Income before income taxes	827	775
Income taxes and taxable-equivalent adjustment	207	194
Net income	620	581
Net income attributable to U.S. Bancorp	620	581
Loans	146,704	141,795
Other earning assets	4,967	2,389
Goodwill	3,475	3,475
Other intangible assets	2,405	2,882
Assets	161,750	154,720
Noninterest-bearing deposits	27,986	26,574
Interest-bearing Deposits	133,802	127,303
Total deposits	161,788	153,877
Total U.S. Bancorp shareholders' equity	14,929	14,998
Wealth Management and Investment Services [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	283	293
Noninterest income	464	430
Total net revenue	747	723
Noninterest expense	444	432
Other intangibles	3	3
Total noninterest expense	447	435
Income before provision and income taxes	300	288
Provision for credit losses	23	(3)
Income before income taxes	277	291
Income taxes and taxable-equivalent adjustment	69	73
Net income	208	218
Net income attributable to U.S. Bancorp	208	218
Loans	10,594	9,818
Other earning assets	281	245
Goodwill	1,617	1,617
Other intangible assets	44	54
Assets	13,936	13,183
Noninterest-bearing deposits	13,184	13,275
Interest-bearing Deposits	68,702	54,135
Total deposits	81,886	67,410
Total U.S. Bancorp shareholders' equity	2,465	2,442
Payments Services [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	652	617
Noninterest income	794	851
Total net revenue	1,446	1,468
Noninterest expense	731	722
Other intangibles	35	31
Total noninterest expense	766	753
Income before provision and income taxes	680	715
Provision for credit losses	262	286
Income before income taxes	418	429
Income taxes and taxable-equivalent adjustment	105	107
Net income	313	322
Net income attributable to U.S. Bancorp	313	322
Loans	33,688	32,414
Other earning assets	399	448
Goodwill	2,811	2,814
Other intangible assets	535	513
Assets	38,562	38,615
Noninterest-bearing deposits	1,402	1,157
Interest-bearing Deposits	114	111
Total deposits	1,516	1,268
Total U.S. Bancorp shareholders' equity	6,081	5,974
Treasury and Corporate Support [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	(26)	17
Noninterest income	186	262
Securities gains (losses), net	50	5
Total net revenue	210	284
Noninterest expense	326	207
Total noninterest expense	326	207
Income before provision and income taxes	(116)	77
Provision for credit losses	160	1
Income before income taxes	(276)	76
Income taxes and taxable-equivalent adjustment	(151)	(105)
Net income	(125)	181
Net (income) loss attributable to noncontrolling interests	(8)	(9)
Net income attributable to U.S. Bancorp	(133)	172
Loans	3,274	3,381
Other earning assets	139,863	127,134
Goodwill	144
Other intangible assets	28
Assets	165,155	149,543
Noninterest-bearing deposits	2,241	2,216
Interest-bearing Deposits	5,340	9,161
Total deposits	7,581	11,377
Total U.S. Bancorp shareholders' equity	11,856	12,829
Consolidated Company [Member]
Segment Reporting Information [Line Items]
Net interest income (taxable-equivalent basis)	3,247	3,286
Noninterest income	2,475	2,286
Securities gains (losses), net	50	5
Total net revenue	5,772	5,577
Noninterest expense	3,274	3,047
Other intangibles	42	40
Total noninterest expense	3,316	3,087
Income before provision and income taxes	2,456	2,490
Provision for credit losses	993	377
Income before income taxes	1,463	2,113
Income taxes and taxable-equivalent adjustment	284	405
Net income	1,179	1,708
Net (income) loss attributable to noncontrolling interests	(8)	(9)
Net income attributable to U.S. Bancorp	1,171	1,699
Loans	297,657	286,110
Other earning assets	150,065	133,384
Goodwill	9,694	9,553
Other intangible assets	3,019	3,458
Assets	494,807	463,399
Noninterest-bearing deposits	74,142	73,433
Interest-bearing Deposits	288,662	261,933
Total deposits	362,804	335,366
Total U.S. Bancorp shareholders' equity	$ 51,146	$ 51,589