Basis of Presentation - Line of Business Financial Performance (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Condensed Income Statement
Net interest income (taxable-equivalent basis)	$ 2,714	$ 2,783	$ 8,095	$ 8,186
Net interest income (taxable-equivalent basis), Percent change	(2.50%)		(1.10%)
Noninterest income	2,180	2,395	6,610	7,008
Noninterest income, Percent change	(9.00%)		(5.70%)
Securities gains (losses), net	(3)	1	8	(18)
Securities gains (losses), net, Percent change
Total net revenue	4,891	5,179	14,713	15,176
Total net revenue, Percent change	(5.60%)		(3.10%)
Noninterest expense	2,510	2,542	7,425	7,562
Noninterest expense, Percent change	(1.30%)		(1.80%)
Other intangibles	55	67	167	208
Other intangibles, Percent change	(17.90%)		(19.70%)
Total noninterest expense	2,565	2,609	7,592	7,770
Total noninterest expense, Percent change	(1.70%)		(2.30%)
Income before provision and income taxes	2,326	2,570	7,121	7,406
Income before provision and income taxes, Percent change	(9.50%)		(3.80%)
Provision for credit losses	298	488	1,063	1,439
Provision for credit losses, Percent change	(38.90%)		(26.10%)
Income before income taxes	2,028	2,082	6,058	5,967
Income before income taxes, Percent change	(2.60%)		1.50%
Income taxes and taxable-equivalent adjustment	598	650	1,797	1,852
Income taxes and taxable-equivalent adjustment, Percent change	(8.00%)		(3.00%)
Net income	1,430	1,432	4,261	4,115
Net income, Percent change	(0.10%)		3.50%
Net (income) loss attributable to noncontrolling interests	38	42	119	112
Net (income) loss attributable to noncontrolling interests, Percent change	(9.50%)		6.30%
Net income attributable to U.S. Bancorp	1,468	1,474	4,380	4,227
Net income attributable to U.S. Bancorp, Percent change	(0.40%)		3.60%
Average Balance Sheet
Commercial	68,064	62,192	66,719	59,790
Commercial, Percent change	9.40%		11.60%
Commercial real estate	38,501	36,630	37,872	36,389
Commercial real estate, Percent change	5.10%		4.10%
Residential mortgages	49,139	40,969	47,055	39,328
Residential mortgages, Percent change	19.90%		19.60%
Credit card	16,931	16,551	16,627	16,675
Credit card, Percent change	2.30%		(0.30%)
Other retail	46,994	47,991	47,034	47,940
Other retail, Percent change	(2.10%)		(1.90%)
Total loans, excluding covered loans	219,629	204,333	215,307	200,122
Total loans, excluding covered loans, Percent change	7.50%		7.60%
Covered loans	9,733	12,595	10,375	13,609
Covered loans, Percent change	(22.70%)		(23.80%)
Total loans	229,362	216,928	225,682	213,731
Total loans, Percent change	5.70%		5.60%
Goodwill	9,161	8,934	9,157	8,936
Goodwill, Percent change	2.50%		2.50%
Other intangible assets	3,399	2,613	3,079	2,715
Other intangible assets, Percent change	30.10%		13.40%
Assets	352,161	345,653	351,048	340,807
Assets, Percent change	1.90%		3.00%
Noninterest-bearing deposits	68,264	68,127	67,183	65,423
Noninterest-bearing deposits, Percent change	0.20%		2.70%
Interest checking	48,235	43,207	48,347	45,522
Interest checking, Percent change	11.60%		6.20%
Savings products	88,065	77,273	86,635	75,360
Savings products, Percent change	14.00%		15.00%
Time deposits	47,804	50,674	46,119	46,673
Time deposits, Percent change	(5.70%)		(1.20%)
Total deposits	252,368	239,281	248,284	232,978
Total deposits, Percent change	5.50%		6.60%
Total U.S. Bancorp shareholders' equity	39,936	38,619	39,675	37,105
Total U.S. Bancorp shareholders' equity, Percent change	3.40%		6.90%
Wholesale Banking and Commercial Real Estate [Member]
Condensed Income Statement
Net interest income (taxable-equivalent basis)	526	528	1,557	1,584
Net interest income (taxable-equivalent basis), Percent change	(0.40%)		(1.70%)
Noninterest income	267	299	819	930
Noninterest income, Percent change	(10.70%)		(11.90%)
Securities gains (losses), net
Securities gains (losses), net, Percent change
Total net revenue	793	827	2,376	2,514
Total net revenue, Percent change	(4.10%)		(5.50%)
Noninterest expense	305	310	932	950
Noninterest expense, Percent change	(1.60%)		(1.90%)
Other intangibles	2	4	6	12
Other intangibles, Percent change	(50.00%)		(50.00%)
Total noninterest expense	307	314	938	962
Total noninterest expense, Percent change	(2.20%)		(2.50%)
Income before provision and income taxes	486	513	1,438	1,552
Income before provision and income taxes, Percent change	(5.30%)		(7.30%)
Provision for credit losses	(38)		(120)	3
Provision for credit losses, Percent change
Income before income taxes	524	513	1,558	1,549
Income before income taxes, Percent change	2.10%		0.60%
Income taxes and taxable-equivalent adjustment	191	187	567	564
Income taxes and taxable-equivalent adjustment, Percent change	2.10%		0.50%
Net income	333	326	991	985
Net income, Percent change	2.10%		0.60%
Net (income) loss attributable to noncontrolling interests
Net (income) loss attributable to noncontrolling interests, Percent change
Net income attributable to U.S. Bancorp	333	326	991	985
Net income attributable to U.S. Bancorp, Percent change	2.10%		0.60%
Average Balance Sheet
Commercial	51,409	46,131	50,331	44,296
Commercial, Percent change	11.40%		13.60%
Commercial real estate	20,663	19,661	20,305	19,594
Commercial real estate, Percent change	5.10%		3.60%
Residential mortgages	24	54	28	61
Residential mortgages, Percent change	(55.60%)		(54.10%)
Credit card
Credit card, Percent change
Other retail	6	7	9	5
Other retail, Percent change	(14.30%)		80.00%
Total loans, excluding covered loans	72,102	65,853	70,673	63,956
Total loans, excluding covered loans, Percent change	9.50%		10.50%
Covered loans	340	813	394	1,010
Covered loans, Percent change	(58.20%)		(61.00%)
Total loans	72,442	66,666	71,067	64,966
Total loans, Percent change	8.70%		9.40%
Goodwill	1,604	1,604	1,604	1,604
Goodwill, Percent change
Other intangible assets	24	34	26	38
Other intangible assets, Percent change	(29.40%)		(31.60%)
Assets	78,785	72,579	77,479	70,806
Assets, Percent change	8.60%		9.40%
Noninterest-bearing deposits	30,925	31,167	30,407	30,762
Noninterest-bearing deposits, Percent change	(0.80%)		(1.20%)
Interest checking	10,038	7,897	10,385	10,621
Interest checking, Percent change	27.10%		(2.20%)
Savings products	15,103	10,358	13,354	8,962
Savings products, Percent change	45.80%		49.00%
Time deposits	22,376	21,247	18,459	17,255
Time deposits, Percent change	5.30%		7.00%
Total deposits	78,442	70,669	72,605	67,600
Total deposits, Percent change	11.00%		7.40%
Total U.S. Bancorp shareholders' equity	7,434	6,378	7,331	6,325
Total U.S. Bancorp shareholders' equity, Percent change	16.60%		15.90%
Consumer and Small Business Banking [Member]
Condensed Income Statement
Net interest income (taxable-equivalent basis)	1,141	1,193	3,427	3,555
Net interest income (taxable-equivalent basis), Percent change	(4.40%)		(3.60%)
Noninterest income	719	930	2,276	2,700
Noninterest income, Percent change	(22.70%)		(15.70%)
Securities gains (losses), net
Securities gains (losses), net, Percent change
Total net revenue	1,860	2,123	5,703	6,255
Total net revenue, Percent change	(12.40%)		(8.80%)
Noninterest expense	1,150	1,236	3,514	3,618
Noninterest expense, Percent change	(7.00%)		(2.90%)
Other intangibles	10	13	30	39
Other intangibles, Percent change	(23.10%)		(23.10%)
Total noninterest expense	1,160	1,249	3,544	3,657
Total noninterest expense, Percent change	(7.10%)		(3.10%)
Income before provision and income taxes	700	874	2,159	2,598
Income before provision and income taxes, Percent change	(19.90%)		(16.90%)
Provision for credit losses	160	349	578	878
Provision for credit losses, Percent change	(54.20%)		(34.20%)
Income before income taxes	540	525	1,581	1,720
Income before income taxes, Percent change	2.90%		(8.10%)
Income taxes and taxable-equivalent adjustment	197	191	576	626
Income taxes and taxable-equivalent adjustment, Percent change	3.10%		(8.00%)
Net income	343	334	1,005	1,094
Net income, Percent change	2.70%		(8.10%)
Net (income) loss attributable to noncontrolling interests
Net (income) loss attributable to noncontrolling interests, Percent change
Net income attributable to U.S. Bancorp	343	334	1,005	1,094
Net income attributable to U.S. Bancorp, Percent change	2.70%		(8.10%)
Average Balance Sheet
Commercial	8,475	8,423	8,468	8,123
Commercial, Percent change	0.60%		4.20%
Commercial real estate	17,084	16,203	16,806	16,065
Commercial real estate, Percent change	5.40%		4.60%
Residential mortgages	48,131	40,530	46,251	38,884
Residential mortgages, Percent change	18.80%		18.90%
Credit card
Credit card, Percent change
Other retail	44,728	45,653	44,737	45,602
Other retail, Percent change	(2.00%)		(1.90%)
Total loans, excluding covered loans	118,418	110,809	116,262	108,674
Total loans, excluding covered loans, Percent change	6.90%		7.00%
Covered loans	6,434	7,384	6,690	7,629
Covered loans, Percent change	(12.90%)		(12.30%)
Total loans	124,852	118,193	122,952	116,303
Total loans, Percent change	5.60%		5.70%
Goodwill	3,515	3,515	3,515	3,515
Goodwill, Percent change
Other intangible assets	2,650	1,764	2,293	1,784
Other intangible assets, Percent change	50.20%		28.50%
Assets	139,539	135,715	139,027	132,973
Assets, Percent change	2.80%		4.60%
Noninterest-bearing deposits	22,460	20,981	21,843	19,638
Noninterest-bearing deposits, Percent change	7.00%		11.20%
Interest checking	32,971	30,020	32,801	29,621
Interest checking, Percent change	9.80%		10.70%
Savings products	46,483	43,647	46,061	43,022
Savings products, Percent change	6.50%		7.10%
Time deposits	20,716	23,624	21,590	24,047
Time deposits, Percent change	(12.30%)		(10.20%)
Total deposits	122,630	118,272	122,295	116,328
Total deposits, Percent change	3.70%		5.10%
Total U.S. Bancorp shareholders' equity	12,154	11,551	12,062	11,135
Total U.S. Bancorp shareholders' equity, Percent change	5.20%		8.30%
Wealth Management and Securities Services [Member]
Condensed Income Statement
Net interest income (taxable-equivalent basis)	85	87	267	264
Net interest income (taxable-equivalent basis), Percent change	(2.30%)		1.10%
Noninterest income	305	282	910	827
Noninterest income, Percent change	8.20%		10.00%
Securities gains (losses), net
Securities gains (losses), net, Percent change
Total net revenue	390	369	1,177	1,091
Total net revenue, Percent change	5.70%		7.90%
Noninterest expense	322	288	962	854
Noninterest expense, Percent change	11.80%		12.60%
Other intangibles	9	10	27	30
Other intangibles, Percent change	(10.00%)		(10.00%)
Total noninterest expense	331	298	989	884
Total noninterest expense, Percent change	11.10%		11.90%
Income before provision and income taxes	59	71	188	207
Income before provision and income taxes, Percent change	(16.90%)		(9.20%)
Provision for credit losses	6	4	7	5
Provision for credit losses, Percent change	50.00%		40.00%
Income before income taxes	53	67	181	202
Income before income taxes, Percent change	(20.90%)		(10.40%)
Income taxes and taxable-equivalent adjustment	19	24	65	73
Income taxes and taxable-equivalent adjustment, Percent change	(20.80%)		(11.00%)
Net income	34	43	116	129
Net income, Percent change	(20.90%)		(10.10%)
Net (income) loss attributable to noncontrolling interests
Net (income) loss attributable to noncontrolling interests, Percent change
Net income attributable to U.S. Bancorp	34	43	116	129
Net income attributable to U.S. Bancorp, Percent change	(20.90%)		(10.10%)
Average Balance Sheet
Commercial	1,774	1,361	1,687	1,264
Commercial, Percent change	30.30%		33.50%
Commercial real estate	653	624	654	607
Commercial real estate, Percent change	4.60%		7.70%
Residential mortgages	983	384	775	379
Residential mortgages, Percent change
Credit card
Credit card, Percent change
Other retail	1,531	1,529	1,544	1,516
Other retail, Percent change	0.10%		1.80%
Total loans, excluding covered loans	4,941	3,898	4,660	3,766
Total loans, excluding covered loans, Percent change	26.80%		23.70%
Covered loans	17	11	14	12
Covered loans, Percent change	54.50%		16.70%
Total loans	4,958	3,909	4,674	3,778
Total loans, Percent change	26.80%		23.70%
Goodwill	1,533	1,469	1,529	1,468
Goodwill, Percent change	4.40%		4.20%
Other intangible assets	166	165	174	172
Other intangible assets, Percent change	0.60%		1.20%
Assets	7,749	6,688	7,513	6,477
Assets, Percent change	15.90%		16.00%
Noninterest-bearing deposits	13,510	14,862	13,807	13,904
Noninterest-bearing deposits, Percent change	(9.10%)		(0.70%)
Interest checking	4,770	3,943	4,716	3,950
Interest checking, Percent change	21.00%		19.40%
Savings products	26,339	23,089	27,081	23,203
Savings products, Percent change	14.10%		16.70%
Time deposits	4,170	5,463	5,228	4,892
Time deposits, Percent change	(23.70%)		6.90%
Total deposits	48,789	47,357	50,832	45,949
Total deposits, Percent change	3.00%		10.60%
Total U.S. Bancorp shareholders' equity	2,398	2,240	2,375	2,223
Total U.S. Bancorp shareholders' equity, Percent change	7.10%		6.80%
Payment Services [Member]
Condensed Income Statement
Net interest income (taxable-equivalent basis)	393	382	1,168	1,154
Net interest income (taxable-equivalent basis), Percent change	2.90%		1.20%
Noninterest income	822	854	2,397	2,402
Noninterest income, Percent change	(3.70%)		(0.20%)
Securities gains (losses), net
Securities gains (losses), net, Percent change
Total net revenue	1,215	1,236	3,565	3,556
Total net revenue, Percent change	(1.70%)		0.30%
Noninterest expense	493	452	1,454	1,344
Noninterest expense, Percent change	9.10%		8.20%
Other intangibles	34	40	104	127
Other intangibles, Percent change	(15.00%)		(18.10%)
Total noninterest expense	527	492	1,558	1,471
Total noninterest expense, Percent change	7.10%		5.90%
Income before provision and income taxes	688	744	2,007	2,085
Income before provision and income taxes, Percent change	(7.50%)		(3.70%)
Provision for credit losses	172	135	553	548
Provision for credit losses, Percent change	27.40%		0.90%
Income before income taxes	516	609	1,454	1,537
Income before income taxes, Percent change	(15.30%)		(5.40%)
Income taxes and taxable-equivalent adjustment	188	222	529	560
Income taxes and taxable-equivalent adjustment, Percent change	(15.30%)		(5.50%)
Net income	328	387	925	977
Net income, Percent change	(15.20%)		(5.30%)
Net (income) loss attributable to noncontrolling interests	(10)	(10)	(29)	(30)
Net (income) loss attributable to noncontrolling interests, Percent change			3.30%
Net income attributable to U.S. Bancorp	318	377	896	947
Net income attributable to U.S. Bancorp, Percent change	(15.60%)		(5.40%)
Average Balance Sheet
Commercial	6,191	6,062	6,030	5,904
Commercial, Percent change	2.10%		2.10%
Commercial real estate
Commercial real estate, Percent change
Residential mortgages
Residential mortgages, Percent change
Credit card	16,931	16,551	16,627	16,675
Credit card, Percent change	2.30%		(0.30%)
Other retail	729	802	744	817
Other retail, Percent change	(9.10%)		(8.90%)
Total loans, excluding covered loans	23,851	23,415	23,401	23,396
Total loans, excluding covered loans, Percent change	1.90%
Covered loans	5	5	5	5
Covered loans, Percent change
Total loans	23,856	23,420	23,406	23,401
Total loans, Percent change	1.90%
Goodwill	2,509	2,346	2,509	2,349
Goodwill, Percent change	6.90%		6.80%
Other intangible assets	557	646	584	717
Other intangible assets, Percent change	(13.80%)		(18.50%)
Assets	30,123	29,517	29,659	29,684
Assets, Percent change	2.10%		(0.10%)
Noninterest-bearing deposits	714	623	694	638
Noninterest-bearing deposits, Percent change	14.60%		8.80%
Interest checking	455	1,346	444	1,329
Interest checking, Percent change	(66.20%)		(66.60%)
Savings products	60	40	54	37
Savings products, Percent change	50.00%		45.90%
Time deposits
Time deposits, Percent change
Total deposits	1,229	2,009	1,192	2,004
Total deposits, Percent change	(38.80%)		(40.50%)
Total U.S. Bancorp shareholders' equity	6,102	5,667	6,033	5,698
Total U.S. Bancorp shareholders' equity, Percent change	7.70%		5.90%
Treasury and Corporate Support [Member]
Condensed Income Statement
Net interest income (taxable-equivalent basis)	569	593	1,676	1,629
Net interest income (taxable-equivalent basis), Percent change	(4.00%)		2.90%
Noninterest income	67	30	208	149
Noninterest income, Percent change			39.60%
Securities gains (losses), net	(3)	1	8	(18)
Securities gains (losses), net, Percent change
Total net revenue	633	624	1,892	1,760
Total net revenue, Percent change	1.40%		7.50%
Noninterest expense	240	256	563	796
Noninterest expense, Percent change	(6.30%)		(29.30%)
Other intangibles
Other intangibles, Percent change
Total noninterest expense	240	256	563	796
Total noninterest expense, Percent change	(6.30%)		(29.30%)
Income before provision and income taxes	393	368	1,329	964
Income before provision and income taxes, Percent change	6.80%		37.90%
Provision for credit losses	(2)		45	5
Provision for credit losses, Percent change
Income before income taxes	395	368	1,284	959
Income before income taxes, Percent change	7.30%		33.90%
Income taxes and taxable-equivalent adjustment	3	26	60	29
Income taxes and taxable-equivalent adjustment, Percent change	(88.50%)
Net income	392	342	1,224	930
Net income, Percent change	14.60%		31.60%
Net (income) loss attributable to noncontrolling interests	48	52	148	142
Net (income) loss attributable to noncontrolling interests, Percent change	(7.70%)		4.20%
Net income attributable to U.S. Bancorp	440	394	1,372	1,072
Net income attributable to U.S. Bancorp, Percent change	11.70%		28.00%
Average Balance Sheet
Commercial	215	215	203	203
Commercial, Percent change
Commercial real estate	101	142	107	123
Commercial real estate, Percent change	(28.90%)		(13.00%)
Residential mortgages	1	1	1	4
Residential mortgages, Percent change			(75.00%)
Credit card
Credit card, Percent change
Other retail
Other retail, Percent change
Total loans, excluding covered loans	317	358	311	330
Total loans, excluding covered loans, Percent change	(11.50%)		(5.80%)
Covered loans	2,937	4,382	3,272	4,953
Covered loans, Percent change	(33.00%)		(33.90%)
Total loans	3,254	4,740	3,583	5,283
Total loans, Percent change	(31.40%)		(32.20%)
Goodwill
Goodwill, Percent change
Other intangible assets	2	4	2	4
Other intangible assets, Percent change	(50.00%)		(50.00%)
Assets	95,965	101,154	97,370	100,867
Assets, Percent change	(5.10%)		(3.50%)
Noninterest-bearing deposits	655	494	432	481
Noninterest-bearing deposits, Percent change	32.60%		(10.20%)
Interest checking	1	1	1	1
Interest checking, Percent change
Savings products	80	139	85	136
Savings products, Percent change	(42.40%)		(37.50%)
Time deposits	542	340	842	479
Time deposits, Percent change	59.40%		75.80%
Total deposits	1,278	974	1,360	1,097
Total deposits, Percent change	31.20%		24.00%
Total U.S. Bancorp shareholders' equity	$ 11,848	$ 12,783	$ 11,874	$ 11,724
Total U.S. Bancorp shareholders' equity, Percent change	(7.30%)		1.30%