Line of Business Financial Performance (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Condensed Income Statement
Securities gains (losses), net	$ 1	$ (9)	$ (18)	$ (22)
Other intangibles	67	75	208	225
Total noninterest expense	2,609	2,476	7,770	7,215
Provision for credit losses	488	519	1,439	1,846
Income before income taxes	2,025	1,742	5,799	4,774
Net income	1,432	1,252	4,115	3,460
Net (income) loss attributable to noncontrolling interests	42	21	112	62
Net income attributable to U.S. Bancorp	1,474	1,273	4,227	3,522
Wholesale Banking and Commercial Real Estate
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	(3.30%)		(0.40%)
Net interest income (taxable-equivalent basis)	526	544	1,580	1,586
Noninterest income, Percent change	(6.60%)		(1.40%)
Noninterest income	296	317	923	936
Total net revenue, Percent change	(4.50%)		(0.80%)
Total net revenue	822	861	2,503	2,522
Noninterest expense, Percent change	(2.20%)		0.60%
Noninterest expense	306	313	941	935
Other intangibles	4	4	12	12
Total noninterest expense, Percent change	(2.20%)		0.60%
Total noninterest expense	310	317	953	947
Income before provision and income taxes, Percent change	(5.90%)		(1.60%)
Income before provision and income taxes	512	544	1,550	1,575
Provision for credit losses, Percent change			(99.20%)
Provision for credit losses		65	3	356
Income before income taxes, Percent change	6.90%		26.90%
Income before income taxes	512	479	1,547	1,219
Income taxes and taxable-equivalent adjustment, Percent change	6.90%		27.10%
Income taxes and taxable-equivalent adjustment	186	174	563	443
Net income, Percent change	6.90%		26.80%
Net income	326	305	984	776
Net (income) loss attributable to noncontrolling interests		(1)		5
Net income attributable to U.S. Bancorp, Percent change	7.20%		26.00%
Net income attributable to U.S. Bancorp	326	304	984	781
Average Balance Sheet
Commercial, Percent change	21.50%		21.90%
Commercial	46,210	38,020	44,376	36,406
Commercial real estate, Percent change	2.40%		1.80%
Commercial real estate	19,681	19,224	19,614	19,271
Residential mortgages, Percent change	(16.90%)		(11.80%)
Residential mortgages	54	65	60	68
Other retail, Percent change	75.00%		(16.70%)
Other retail	7	4	5	6
Total loans, excluding covered loans, Percent change	15.10%		14.90%
Total loans, excluding covered loans	65,952	57,313	64,055	55,751
Covered loans, Percent change	(38.90%)		(36.90%)
Covered loans	806	1,320	1,003	1,589
Total loans, Percent change	13.90%		13.50%
Total loans	66,758	58,633	65,058	57,340
Other intangible assets, Percent change	(32.00%)		(30.90%)
Assets, Percent change	12.50%		12.10%
Noninterest-bearing deposits, Percent change	11.40%		29.00%
Interest checking, Percent change	(28.10%)		(18.60%)
Savings products, Percent change	10.40%		(6.70%)
Time deposits, Percent change	43.90%		15.90%
Total deposits, Percent change	12.00%		10.10%
Total U.S. Bancorp shareholders' equity, Percent change	13.90%		14.40%
Goodwill	1,604	1,604	1,604	1,604
Other intangible assets	34	50	38	55
Assets	72,668	64,594	70,895	63,218
Noninterest-bearing deposits	31,025	27,848	30,630	23,749
Interest checking	7,890	10,974	10,608	13,024
Savings products	10,320	9,351	8,918	9,555
Time deposits	21,202	14,732	17,210	14,845
Total deposits	70,437	62,905	67,366	61,173
Total U.S. Bancorp shareholders' equity	6,383	5,604	6,327	5,533
Consumer and Small Business Banking
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	3.30%		4.10%
Net interest income (taxable-equivalent basis)	1,191	1,153	3,551	3,412
Noninterest income, Percent change	31.70%		35.40%
Noninterest income	931	707	2,701	1,995
Total net revenue, Percent change	14.10%		15.60%
Total net revenue	2,122	1,860	6,252	5,407
Noninterest expense, Percent change	7.50%		7.10%
Noninterest expense	1,251	1,164	3,673	3,430
Other intangibles, Percent change	(31.60%)		(31.60%)
Other intangibles	13	19	39	57
Total noninterest expense, Percent change	6.80%		6.50%
Total noninterest expense	1,264	1,183	3,712	3,487
Income before provision and income taxes, Percent change	26.70%		32.30%
Income before provision and income taxes	858	677	2,540	1,920
Provision for credit losses, Percent change	4.80%		(20.20%)
Provision for credit losses	346	330	875	1,097
Income before income taxes, Percent change	47.60%
Income before income taxes	512	347	1,665	823
Income taxes and taxable-equivalent adjustment, Percent change	47.60%
Income taxes and taxable-equivalent adjustment	186	126	605	299
Net income, Percent change	47.50%
Net income	326	221	1,060	524
Net (income) loss attributable to noncontrolling interests				(1)
Net income attributable to U.S. Bancorp, Percent change	47.50%
Net income attributable to U.S. Bancorp	326	221	1,060	523
Average Balance Sheet
Commercial, Percent change	14.50%		12.20%
Commercial	8,398	7,332	8,127	7,243
Commercial real estate, Percent change	3.50%		3.90%
Commercial real estate	16,208	15,656	16,070	15,462
Residential mortgages, Percent change	20.80%		20.00%
Residential mortgages	40,526	33,561	38,883	32,391
Other retail, Percent change	(0.70%)		(0.20%)
Other retail	45,656	46,000	45,604	45,691
Total loans, excluding covered loans, Percent change	8.00%		7.80%
Total loans, excluding covered loans	110,788	102,549	108,684	100,787
Covered loans, Percent change	(10.50%)		(10.30%)
Covered loans	7,396	8,266	7,642	8,520
Total loans, Percent change	6.60%		6.40%
Total loans	118,184	110,815	116,326	109,307
Goodwill, Percent change			(0.20%)
Other intangible assets, Percent change	(9.40%)		(16.60%)
Assets, Percent change	9.60%		8.30%
Noninterest-bearing deposits, Percent change	18.30%		12.00%
Interest checking, Percent change	11.10%		13.10%
Savings products, Percent change	7.30%		7.00%
Time deposits, Percent change	(3.40%)		(1.60%)
Total deposits, Percent change	7.60%		7.40%
Total U.S. Bancorp shareholders' equity, Percent change	24.00%		20.20%
Goodwill	3,515	3,515	3,515	3,521
Other intangible assets	1,764	1,946	1,784	2,138
Assets	135,828	123,960	133,108	122,942
Noninterest-bearing deposits	21,127	17,852	19,774	17,649
Interest checking	30,051	27,048	29,660	26,228
Savings products	43,723	40,762	43,106	40,290
Time deposits	23,673	24,500	24,097	24,478
Total deposits	118,574	110,162	116,637	108,645
Total U.S. Bancorp shareholders' equity	11,562	9,327	11,147	9,277
Wealth Management and Securities Services
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	(3.40%)		1.50%
Net interest income (taxable-equivalent basis)	86	89	263	259
Noninterest income, Percent change	11.40%		4.40%
Noninterest income	283	254	828	793
Total net revenue, Percent change	7.60%		3.70%
Total net revenue	369	343	1,091	1,052
Noninterest expense, Percent change	8.20%		6.70%
Noninterest expense	289	267	856	802
Other intangibles, Percent change	11.10%		11.10%
Other intangibles	10	9	30	27
Total noninterest expense, Percent change	8.30%		6.90%
Total noninterest expense	299	276	886	829
Income before provision and income taxes, Percent change	4.50%		(8.10%)
Income before provision and income taxes	70	67	205	223
Provision for credit losses	4	2	6	3
Income before income taxes, Percent change	1.50%		(9.50%)
Income before income taxes	66	65	199	220
Income taxes and taxable-equivalent adjustment, Percent change			(11.10%)
Income taxes and taxable-equivalent adjustment	24	24	72	81
Net income, Percent change	2.40%		(8.60%)
Net income	42	41	127	139
Net income attributable to U.S. Bancorp, Percent change	2.40%		(8.60%)
Net income attributable to U.S. Bancorp	42	41	127	139
Average Balance Sheet
Commercial, Percent change	30.80%		18.50%
Commercial	1,398	1,069	1,267	1,069
Commercial real estate, Percent change	5.60%		1.20%
Commercial real estate	599	567	582	575
Residential mortgages, Percent change	(2.00%)		(1.60%)
Residential mortgages	384	392	379	385
Other retail, Percent change	2.40%		(2.20%)
Other retail	1,526	1,490	1,513	1,547
Total loans, excluding covered loans, Percent change	11.10%		4.60%
Total loans, excluding covered loans	3,907	3,518	3,741	3,576
Covered loans, Percent change	(8.30%)
Covered loans	11	12	12	12
Total loans, Percent change	11.00%		4.60%
Total loans	3,918	3,530	3,753	3,588
Goodwill, Percent change	0.40%		0.30%
Other intangible assets, Percent change	(7.80%)		(8.50%)
Assets, Percent change	12.10%		7.20%
Noninterest-bearing deposits, Percent change	25.90%		70.20%
Interest checking, Percent change	38.20%		34.90%
Savings products, Percent change	8.10%		8.60%
Time deposits, Percent change	14.00%		(17.40%)
Total deposits, Percent change	16.10%		19.70%
Total U.S. Bancorp shareholders' equity, Percent change	8.00%		7.00%
Goodwill	1,469	1,463	1,468	1,463
Other intangible assets	165	179	172	188
Assets	6,698	5,976	6,454	6,018
Noninterest-bearing deposits	14,856	11,801	13,899	8,176
Interest checking	3,919	2,835	3,924	2,908
Savings products	23,051	21,314	23,163	21,329
Time deposits	5,459	4,787	4,888	5,919
Total deposits	47,285	40,737	45,874	38,332
Total U.S. Bancorp shareholders' equity	2,241	2,075	2,223	2,078
Payment Services
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	14.00%		16.00%
Net interest income (taxable-equivalent basis)	382	335	1,154	995
Noninterest income, Percent change	(0.40%)		(1.80%)
Noninterest income	851	854	2,399	2,443
Total net revenue, Percent change	3.70%		3.30%
Total net revenue	1,233	1,189	3,553	3,438
Noninterest expense, Percent change	0.40%		2.90%
Noninterest expense	451	449	1,344	1,306
Other intangibles, Percent change	(7.00%)		(1.60%)
Other intangibles	40	43	127	129
Total noninterest expense, Percent change	(0.20%)		2.50%
Total noninterest expense	491	492	1,471	1,435
Income before provision and income taxes, Percent change	6.50%		3.90%
Income before provision and income taxes	742	697	2,082	2,003
Provision for credit losses, Percent change	8.00%		45.40%
Provision for credit losses	135	125	548	377
Income before income taxes, Percent change	6.10%		(5.70%)
Income before income taxes	607	572	1,534	1,626
Income taxes and taxable-equivalent adjustment, Percent change	6.30%		(5.60%)
Income taxes and taxable-equivalent adjustment	221	208	558	591
Net income, Percent change	6.00%		(5.70%)
Net income	386	364	976	1,035
Net (income) loss attributable to noncontrolling interests, Percent change			(3.40%)
Net (income) loss attributable to noncontrolling interests	(10)	(10)	(30)	(29)
Net income attributable to U.S. Bancorp, Percent change	6.20%		(6.00%)
Net income attributable to U.S. Bancorp	376	354	946	1,006
Average Balance Sheet
Commercial, Percent change	4.00%		6.20%
Commercial	6,062	5,828	5,904	5,561
Credit card, Percent change	3.10%		4.10%
Credit card	16,551	16,057	16,675	16,022
Other retail, Percent change	(9.40%)		(10.10%)
Other retail	802	885	817	909
Total loans, excluding covered loans, Percent change	2.80%		4.00%
Total loans, excluding covered loans	23,415	22,770	23,396	22,492
Covered loans, Percent change			25.00%
Covered loans	5	5	5	4
Total loans, Percent change	2.80%		4.00%
Total loans	23,420	22,775	23,401	22,496
Goodwill, Percent change	(0.90%)		(0.70%)
Other intangible assets, Percent change	(16.60%)		(11.00%)
Assets, Percent change	4.60%		7.20%
Noninterest-bearing deposits, Percent change	(4.60%)		(6.70%)
Savings products, Percent change	29.00%		27.60%
Total U.S. Bancorp shareholders' equity, Percent change	7.20%		7.80%
Goodwill	2,346	2,367	2,349	2,365
Other intangible assets	646	775	717	806
Assets	29,522	28,235	29,685	27,679
Noninterest-bearing deposits	623	653	638	684
Interest checking	1,346	184	1,329	174
Savings products	40	31	37	29
Total deposits	2,009	868	2,004	887
Total U.S. Bancorp shareholders' equity	5,654	5,276	5,681	5,272
Treasury and Corporate Support
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	18.90%		15.10%
Net interest income (taxable-equivalent basis)	598	503	1,638	1,423
Noninterest income, Percent change	(29.20%)		(14.70%)
Noninterest income	34	48	157	184
Securities gains (losses), net, Percent change			18.20%
Securities gains (losses), net	1	(9)	(18)	(22)
Total net revenue, Percent change	16.80%		12.10%
Total net revenue	633	542	1,777	1,585
Noninterest expense, Percent change	17.80%		44.70%
Noninterest expense	245	208	748	517
Total noninterest expense, Percent change	17.80%		44.70%
Total noninterest expense	245	208	748	517
Income before provision and income taxes, Percent change	16.20%		(3.70%)
Income before provision and income taxes	388	334	1,029	1,068
Provision for credit losses, Percent change			(46.20%)
Provision for credit losses	3	(3)	7	13
Income before income taxes, Percent change	14.20%		(3.10%)
Income before income taxes	385	337	1,022	1,055
Income taxes and taxable-equivalent adjustment, Percent change			(21.70%)
Income taxes and taxable-equivalent adjustment	33	16	54	69
Net income, Percent change	9.70%		(1.80%)
Net income	352	321	968	986
Net (income) loss attributable to noncontrolling interests, Percent change	62.50%		63.20%
Net (income) loss attributable to noncontrolling interests	52	32	142	87
Net income attributable to U.S. Bancorp, Percent change	14.40%		3.40%
Net income attributable to U.S. Bancorp	404	353	1,110	1,073
Average Balance Sheet
Commercial, Percent change	30.50%		11.50%
Commercial	124	95	116	104
Commercial real estate, Percent change	16.40%		12.80%
Commercial real estate	142	122	123	109
Residential mortgages, Percent change	(37.50%)		(40.00%)
Residential mortgages	5	8	6	10
Other retail		1	1	1
Total loans, excluding covered loans, Percent change	19.90%		9.80%
Total loans, excluding covered loans	271	226	246	224
Covered loans, Percent change	(29.30%)		(24.80%)
Covered loans	4,377	6,190	4,947	6,578
Total loans, Percent change	(27.60%)		(23.70%)
Total loans	4,648	6,416	5,193	6,802
Other intangible assets, Percent change	(20.00%)		(20.00%)
Assets, Percent change	2.10%		6.80%
Noninterest-bearing deposits, Percent change	9.70%		60.70%
Savings products, Percent change	(32.90%)		(29.20%)
Total deposits, Percent change	40.00%		57.20%
Total U.S. Bancorp shareholders' equity, Percent change	18.30%		22.90%
Other intangible assets	4	5	4	5
Assets	100,937	98,816	100,665	94,222
Noninterest-bearing deposits	496	452	482	300
Interest checking	1	1	1	1
Savings products	139	207	136	192
Time deposits	340	37	478	205
Total deposits	976	697	1,097	698
Total U.S. Bancorp shareholders' equity	12,779	10,805	11,727	9,539
Consolidated Company
Condensed Income Statement
Net interest income (taxable-equivalent basis), Percent change	6.10%		6.70%
Net interest income (taxable-equivalent basis)	2,783	2,624	8,186	7,675
Noninterest income, Percent change	9.90%		10.30%
Noninterest income	2,395	2,180	7,008	6,351
Securities gains (losses), net, Percent change			18.20%
Securities gains (losses), net	1	(9)	(18)	(22)
Total net revenue, Percent change	8.00%		8.40%
Total net revenue	5,179	4,795	15,176	14,004
Noninterest expense, Percent change	5.90%		8.20%
Noninterest expense	2,542	2,401	7,562	6,990
Other intangibles, Percent change	(10.70%)		(7.60%)
Other intangibles	67	75	208	225
Total noninterest expense, Percent change	5.40%		7.70%
Total noninterest expense	2,609	2,476	7,770	7,215
Income before provision and income taxes, Percent change	10.80%		9.10%
Income before provision and income taxes	2,570	2,319	7,406	6,789
Provision for credit losses, Percent change	(6.00%)		(22.00%)
Provision for credit losses	488	519	1,439	1,846
Income before income taxes, Percent change	15.70%		20.70%
Income before income taxes	2,082	1,800	5,967	4,943
Income taxes and taxable-equivalent adjustment, Percent change	18.60%		24.90%
Income taxes and taxable-equivalent adjustment	650	548	1,852	1,483
Net income, Percent change	14.40%		18.90%
Net income	1,432	1,252	4,115	3,460
Net (income) loss attributable to noncontrolling interests, Percent change			80.60%
Net (income) loss attributable to noncontrolling interests	42	21	112	62
Net income attributable to U.S. Bancorp, Percent change	15.80%		20.00%
Net income attributable to U.S. Bancorp	1,474	1,273	4,227	3,522
Average Balance Sheet
Commercial, Percent change	18.80%		18.70%
Commercial	62,192	52,344	59,790	50,383
Commercial real estate, Percent change	3.00%		2.70%
Commercial real estate	36,630	35,569	36,389	35,417
Residential mortgages, Percent change	20.40%		19.70%
Residential mortgages	40,969	34,026	39,328	32,854
Credit card, Percent change	3.10%		4.10%
Credit card	16,551	16,057	16,675	16,022
Other retail, Percent change	(0.80%)		(0.40%)
Other retail	47,991	48,380	47,940	48,154
Total loans, excluding covered loans, Percent change	9.60%		9.50%
Total loans, excluding covered loans	204,333	186,376	200,122	182,830
Covered loans, Percent change	(20.20%)		(18.50%)
Covered loans	12,595	15,793	13,609	16,703
Total loans, Percent change	7.30%		7.10%
Total loans	216,928	202,169	213,731	199,533
Goodwill, Percent change	(0.20%)		(0.20%)
Other intangible assets, Percent change	(11.60%)		(14.90%)
Assets, Percent change	7.50%		8.50%
Noninterest-bearing deposits, Percent change	16.20%		29.40%
Interest checking, Percent change	5.30%		7.50%
Savings products, Percent change	7.80%		5.60%
Time deposits, Percent change	15.00%		2.70%
Total deposits, Percent change	11.10%		11.10%
Total U.S. Bancorp shareholders' equity, Percent change	16.70%		17.10%
Goodwill	8,934	8,949	8,936	8,953
Other intangible assets	2,613	2,955	2,715	3,192
Assets	345,653	321,581	340,807	314,079
Noninterest-bearing deposits	68,127	58,606	65,423	50,558
Interest checking	43,207	41,042	45,522	42,335
Savings products	77,273	71,665	75,360	71,395
Time deposits	50,674	44,056	46,673	45,447
Total deposits	239,281	215,369	232,978	209,735
Total U.S. Bancorp shareholders' equity	$ 38,619	$ 33,087	$ 37,105	$ 31,699