Honda Motor (HMC) 20-F 20 Jun 14 2014 FY Annual report (foreign) Financial data

Document_and_Entity_Informatio

Document and Entity Information	12 Months Ended
	Mar. 31, 2014
Document Type	'20-F
Amendment Flag	'false
Document Period End Date	31-Mar-14
Document Fiscal Year Focus	'2014
Document Fiscal Period Focus	'FY
Trading Symbol	'HMC
Entity Registrant Name	'HONDA MOTOR CO LTD
Entity Central Index Key	'0000715153
Current Fiscal Year End Date	'--03-31
Entity Well-known Seasoned Issuer	'Yes
Entity Current Reporting Status	'Yes
Entity Filer Category	'Large Accelerated Filer
Entity Common Stock, Shares Outstanding	1,802,291,196

Consolidated_Balance_Sheets

Consolidated Balance Sheets (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	¥ 1,168,914	¥ 1,206,128
Trade accounts and notes receivable, net of allowance for doubtful accounts of ¥7,885 million in 2013 and ¥9,677 million in 2014 (notes 3, 9 and 20)	1,158,671	1,005,981
Finance subsidiaries-receivables, net (notes 3, 4, 9 and 20)	1,464,215	1,243,002
Inventories (notes 5 and 9)	1,302,895	1,215,421
Deferred income taxes (notes 11 and 20)	202,123	234,075
Other current assets (notes 3, 4, 7, 9 and 17)	474,448	418,446
Total current assets	5,771,266	5,323,053
Finance subsidiaries-receivables, net (notes 3, 4, 9 and 20)	3,317,553	2,788,135
Investments and advances:	'	'
Investments in and advances to affiliates (note 6)	564,266	459,110
Other, including marketable equity securities (notes 3, 4 and 7)	253,661	209,680
Total investments and advances	817,927	668,790
Property on operating leases (note 8):	'	'
Vehicles	2,718,131	2,243,424
Less accumulated depreciation	481,410	400,292
Net property on operating leases	2,236,721	1,843,132
Property, plant and equipment, at cost (note 9):	'	'
Land	521,806	515,661
Buildings	1,895,140	1,686,638
Machinery and equipment	4,384,255	3,832,090
Construction in progress	339,093	288,073
Gross property, plant and equipment	7,140,294	6,322,462
Less accumulated depreciation and amortization	4,321,862	3,922,932
Net property, plant and equipment	2,818,432	2,399,530
Other assets, net of allowance for doubtful accounts of ¥22,754 million in 2013 and ¥22,100 million in 2014 (notes 3, 4, 9, 11, 13, 17 and 20)	660,132	612,717
Total assets	15,622,031	13,635,357
Current liabilities:	'	'
Short-term debt (notes 4 and 9)	1,319,344	1,238,297
Current portion of long-term debt (notes 4 and 9)	1,303,464	945,046
Trade payables:	'	'
Notes	28,501	31,354
Accounts	1,071,179	956,660
Accrued expenses (note 13)	626,503	593,570
Income taxes payable (note 11)	43,085	48,454
Other current liabilities (notes 9, 11 and 17)	319,253	275,623
Total current liabilities	4,711,329	4,089,004
Long-term debt, excluding current portion (notes 4 and 9)	3,234,066	2,710,845
Other liabilities (notes 4, 10, 11 and 13)	1,563,238	1,630,085
Total liabilities	9,508,633	8,429,934
Honda Motor Co., Ltd. shareholders' equity:	'	'
Common stock, authorized 7,086,000,000 shares; issued 1,811,428,430 shares	86,067	86,067
Capital surplus	171,117	171,117
Legal reserves (note 12)	49,276	47,583
Retained earnings (notes 1(c) and 12)	6,431,682	6,001,649
Accumulated other comprehensive income (loss), net (notes 7, 11, 13, 15 and 17)	-793,014	-1,236,792
Treasury stock, at cost 9,131,140 shares in 2013 and 9,137,234 shares in 2014	-26,149	-26,124
Total Honda Motor Co., Ltd. shareholders' equity	5,918,979	5,043,500
Noncontrolling interests (note 1(c))	194,419	161,923
Total equity	6,113,398	5,205,423
Commitments and contingent liabilities (notes 18 and 19)	'	'
Total liabilities and equity	¥ 15,622,031	¥ 13,635,357

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, except Share data, unless otherwise specified
Trade accounts and notes receivable, allowance for doubtful accounts	¥ 9,677	¥ 7,885
Other assets, allowance for doubtful accounts	¥ 22,100	¥ 22,754
Common stock, authorized (in shares)	7,086,000,000	7,086,000,000
Common stock, issued (in shares)	1,811,428,430	1,811,428,430
Treasury stock (in shares)	9,137,234	9,131,140

Consolidated_Statements_of_Inc

Consolidated Statements of Income (JPY ¥)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Net sales and other operating revenue (note 2)	¥ 11,842,451	¥ 9,877,947	¥ 7,948,095
Operating costs and expenses:	'	'	'
Cost of sales (notes 1(k), 1(u), 2 and 13)	8,761,083	7,345,162	5,919,633
Selling, general and administrative (notes 1(k), 1(u) and 13)	1,696,957	1,427,705	1,277,280
Research and development (note 1(k))	634,130	560,270	519,818
Total operating costs and expenses	11,092,170	9,333,137	7,716,731
Operating income	750,281	544,810	231,364
Other income (expenses):	'	'	'
Interest income	24,026	25,742	33,461
Interest expense	-12,703	-12,157	-10,378
Other, net (notes 1(p), 7, 15 and 17)	-32,664	-69,504	2,956
Total other income (expenses)	-21,341	-55,919	26,039
Income before income taxes and equity in income of affiliates	728,940	488,891	257,403
Income tax expense (notes 11 and 15):	'	'	'
Current	207,236	125,724	86,074
Deferred	45,426	53,252	49,661
Total	252,662	178,976	135,735
Income before equity in income of affiliates	476,278	309,915	121,668
Equity in income of affiliates (note 6)	132,471	82,723	100,406
Net income	608,749	392,638	222,074
Less: Net income attributable to noncontrolling interests	34,642	25,489	10,592
Net income attributable to Honda Motor Co., Ltd.	¥ 574,107	¥ 367,149	¥ 211,482
Basic net income attributable to Honda Motor Co., Ltd. per common share (in yen per share) (note 1(o))	¥ 318.54	¥ 203.71	¥ 117.34

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Net income	¥ 608,749		¥ 392,638		¥ 222,074
Other comprehensive income (loss), net of tax:	'		'		'
Adjustments from foreign currency translation	333,659		430,812		-118,135
Unrealized gains (losses) on available-for-sale securities, net	15,252		7,984		5,812
Unrealized gains (losses) on derivative instruments, net	237		-52		-29
Pension and other postretirement benefits adjustments (note 13)	107,718	[1]	-15,297	[1]	-39,653	[1]
Other comprehensive income (loss), net of tax (note 15)	456,866		423,447		-152,005
Comprehensive income (loss)	1,065,615		816,085		70,069
Less: Comprehensive income attributable to noncontrolling interests	47,730		39,650		9,285
Comprehensive income (loss) attributable to Honda Motor Co., Ltd.	¥ 1,017,885		¥ 776,435		¥ 60,784
[1]	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Equity (JPY ¥)	Total	Common stock	Capital surplus	Legal reserves	Retained earnings	Accumulated other comprehensive income (loss), net	Treasury stock	Total Honda Motor Co., Ltd. shareholders' equity	Noncontrolling interests
In Millions, unless otherwise specified
Balance at beginning of year at Mar. 31, 2011 (Scenario Previously Reported [Member])	¥ 4,572,524	¥ 86,067	¥ 172,529	¥ 46,330	¥ 5,656,151	¥ (1,495,380)	¥ (26,110)	¥ 4,439,587	¥ 132,937
Balance at beginning of year (Restatement Adjustment [Member]) (Adjustment resulting from change in fiscal year-end of a subsidiary, net of tax (note 1(c)))	7,681	'	'	'	6,023	'	'	6,023	1,658
Balance at beginning of year at Mar. 31, 2011	4,580,205	86,067	172,529	46,330	5,662,174	-1,495,380	-26,110	4,445,610	134,595
Transfer to legal reserves	'	'	'	854	-854	'	'	'	'
Dividends paid to Honda Motor Co., Ltd. shareholders	-108,138	'	'	'	-108,138	'	'	-108,138	'
Dividends paid to noncontrolling interests	-15,763	'	'	'	'	'	'	'	-15,763
Capital transactions and others	-783	'	'	'	'	'	'	'	-783
Comprehensive income (loss):	'	'	'	'	'	'	'	'	'
Net income	222,074	'	'	'	211,482	'	'	211,482	10,592
Other comprehensive income (loss), net of tax (note 15)	-152,005	'	'	'	'	-150,698	'	-150,698	-1,307
Total comprehensive income (loss)	70,069	'	'	'	'	'	'	60,784	9,285
Purchase of treasury stock	-8	'	'	'	'	'	-8	-8	'
Reissuance of treasury stock	1	'	'	'	'	'	1	1	'
Balance at end of year at Mar. 31, 2012	4,525,583	86,067	172,529	47,184	5,764,664	-1,646,078	-26,117	4,398,249	127,334
Transfer to legal reserves	'	'	'	399	-399	'	'	'	'
Dividends paid to Honda Motor Co., Ltd. shareholders	-129,765	'	'	'	-129,765	'	'	-129,765	'
Dividends paid to noncontrolling interests	-6,250	'	'	'	'	'	'	'	-6,250
Capital transactions and others	-223	'	-1,412	'	'	'	'	-1,412	1,189
Comprehensive income (loss):	'	'	'	'	'	'	'	'	'
Net income	392,638	'	'	'	367,149	'	'	367,149	25,489
Other comprehensive income (loss), net of tax (note 15)	423,447	'	'	'	'	409,286	'	409,286	14,161
Total comprehensive income (loss)	816,085	'	'	'	'	'	'	776,435	39,650
Purchase of treasury stock	-8	'	'	'	'	'	-8	-8	'
Reissuance of treasury stock	1	'	'	'	'	'	1	1	'
Balance at end of year at Mar. 31, 2013	5,205,423	86,067	171,117	47,583	6,001,649	-1,236,792	-26,124	5,043,500	161,923
Transfer to legal reserves	'	'	'	1,693	-1,693	'	'	'	'
Dividends paid to Honda Motor Co., Ltd. shareholders	-142,381	'	'	'	-142,381	'	'	-142,381	'
Dividends paid to noncontrolling interests	-9,677	'	'	'	'	'	'	'	-9,677
Capital transactions and others	-5,557	'	'	'	'	'	'	'	-5,557
Comprehensive income (loss):	'	'	'	'	'	'	'	'	'
Net income	608,749	'	'	'	574,107	'	'	574,107	34,642
Other comprehensive income (loss), net of tax (note 15)	456,866	'	'	'	'	443,778	'	443,778	13,088
Total comprehensive income (loss)	1,065,615	'	'	'	'	'	'	1,017,885	47,730
Purchase of treasury stock	-26	'	'	'	'	'	-26	-26	'
Reissuance of treasury stock	1	'	'	'	'	'	1	1	'
Balance at end of year at Mar. 31, 2014	¥ 6,113,398	¥ 86,067	¥ 171,117	¥ 49,276	¥ 6,431,682	¥ (793,014)	¥ (26,149)	¥ 5,918,979	¥ 194,419

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities (note 14):	'	'	'
Net income	¥ 608,749	¥ 392,638	¥ 222,074
Adjustments to reconcile net income to net cash provided by operating activities:	'	'	'
Depreciation excluding property on operating leases	442,318	335,536	345,105
Depreciation of property on operating leases	352,402	254,933	209,762
Deferred income taxes	45,426	53,252	49,661
Equity in income of affiliates	-132,471	-82,723	-100,406
Dividends from affiliates	98,955	84,705	95,106
Provision for credit and lease residual losses on finance subsidiaries-receivables	18,904	10,059	13,032
Impairment loss on investments in securities	'	'	1,062
Damaged and impairment loss on long-lived assets excluding property on operating leases (note 1(u))	'	'	10,590
Impairment loss on property on operating leases	3,301	4,773	1,514
Loss (gain) on derivative instruments, net	-39,376	35,027	-1,847
Decrease (increase) in assets:	'	'	'
Trade accounts and notes receivable	-92,638	-90,495	-35,475
Inventories	-2,901	-74,662	-154,222
Other current assets	-7,363	2,019	2,883
Other assets	-59,816	-27,243	-24,000
Increase (decrease) in liabilities:	'	'	'
Trade accounts and notes payable	70,988	-95,192	242,814
Accrued expenses	49,718	52,021	-25,718
Income taxes payable	-8,688	21,764	-7,568
Other current liabilities	31,404	-4,489	-12,395
Other liabilities	-53,815	-4,384	-14,744
Other, net	-95,906	-66,795	-55,690
Net cash provided by operating activities	1,229,191	800,744	761,538
Cash flows from investing activities:	'	'	'
Increase in investments and advances	-45,617	-34,426	-23,129
Decrease in investments and advances	58,243	19,850	14,647
Payments for purchases of available-for-sale securities	-44,459	-5,642	-1,784
Proceeds from sales of available-for-sale securities	14,501	1,347	1,879
Payments for purchases of held-to-maturity securities	-20,771	-5,186	-26,078
Proceeds from redemptions of held-to-maturity securities	3,358	17,005	47,193
Proceeds from sales of subsidiaries, net of cash and cash equivalents disposed	9,129	'	'
Proceeds from sales of investments in affiliates	5,363	'	9,957
Capital expenditures	-774,006	-626,879	-397,218
Proceeds from sales of property, plant and equipment	34,069	44,182	23,260
Proceeds from insurance recoveries for damaged property, plant and equipment (note 1(u))	6,800	9,600	16,217
Acquisitions of finance subsidiaries-receivables	-2,792,774	-1,951,802	-1,784,720
Collections of finance subsidiaries-receivables	2,354,029	1,833,669	1,765,204
Purchases of operating lease assets	-1,127,840	-793,118	-683,767
Proceeds from sales of operating lease assets	611,317	418,086	365,270
Other, net	-86	3,558	'
Net cash used in investing activities	-1,708,744	-1,069,756	-673,069
Cash flows from financing activities:	'	'	'
Proceeds from short-term debt	8,559,288	6,775,636	6,778,336
Repayments of short-term debt	-8,563,616	-6,621,897	-6,882,932
Proceeds from long-term debt	1,588,826	1,101,469	1,151,971
Repayments of long-term debt	-1,039,595	-970,702	-967,588
Dividends paid (note 12)	-142,381	-129,765	-108,138
Dividends paid to noncontrolling interests	-9,677	-6,250	-15,763
Sales (purchases) of treasury stock, net	-25	-7	-7
Other, net	-22,265	-28,917	-24,109
Net cash provided by (used in) financing activities	370,555	119,567	-68,230
Effect of exchange rate changes on cash and cash equivalents	71,784	108,460	-52,150
Net change in cash and cash equivalents	-37,214	-40,985	-31,911
Cash and cash equivalents at beginning of year	1,206,128	1,247,113	1,279,024
Cash and cash equivalents at end of year	¥ 1,168,914	¥ 1,206,128	¥ 1,247,113

General_and_Summary_of_Signifi

General and Summary of Significant Accounting Policies	12 Months Ended
	Mar. 31, 2014
General and Summary of Significant Accounting Policies	'
	(1) General and Summary of Significant Accounting Policies
	(a) Description of Business
	Honda Motor Co., Ltd. (the “Company”) and its subsidiaries (collectively “Honda”) mainly develop, manufacture and distribute motorcycles, automobiles, power products, and also provide financing for the sale of those products. Principal manufacturing facilities are located in Japan, the United States of America, Canada, Mexico, the United Kingdom, Italy, China, India, Thailand, Vietnam, Indonesia, Argentina, Brazil and Turkey.
	(b) Basis of Presenting Consolidated Financial Statements
	The Company and its Japanese subsidiaries maintain their books of account in conformity with financial accounting standards of Japan, and its foreign subsidiaries generally maintain their books of account in conformity with those of the countries of their domicile.
	The consolidated financial statements presented herein have been prepared in a manner and reflect the adjustments which are necessary to conform them with U.S. generally accepted accounting principles (U.S.GAAP).
	(c) Consolidation Policy
	The consolidated financial statements include the accounts of the Company, its subsidiaries and those variable interest entities where Honda is the primary beneficiary. All significant intercompany balances and transactions have been eliminated in consolidation.
	Noncontrolling interests in the net assets of subsidiary are reported as a component of equity in the consolidated financial statements. Changes in a parent’s ownership interest while the parent retains its controlling financial interest in its subsidiary are accounted for as equity transactions. Noncontrolling interests in a subsidiary’s earnings or losses are reported as a component of net income in the consolidated financial statements.
	Investments in affiliates in which Honda has the ability to exercise significant influence over their operating and financial policies, but where Honda does not have a controlling financial interest are accounted for using the equity method.
	There are some subsidiaries and affiliates of which the fiscal year-end is December 31.
	Effective April 1, 2013, a subsidiary of the Company changed its fiscal year-end from December 31 to March 31. As a result, the Company eliminated the previously existing three month differences between the reporting periods of the Company and the subsidiary in the consolidated financial statements. The elimination of the lag period represents a change in accounting principle and has been reported by retrospective application. The impacts on the retained earnings and noncontrolling interests as of April 1, 2011 are ¥6,023 million and ¥1,658 million, respectively. Honda believes the effect of the retrospective application is not material to the Company’s consolidated financial statements as of and for the year ended March 31, 2012 and 2013, and therefore the Company’s consolidated financial statements have not been retrospectively adjusted, except for the adjustment to retained earnings and noncontrolling interests as of April 1, 2011.
	(d) Use of Estimates
	Management of Honda has made a number of estimates and assumptions relating to the reporting of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities to prepare its consolidated financial statements in conformity with U.S. GAAP. Significant items subject to such estimates and assumptions include, but are not limited to, allowance for credit losses, losses on lease residual values, realizable values of inventories, realization of deferred tax assets, damaged and impairment losses on long-lived assets, unrecognized tax benefits, product warranty obligations, the fair values of assets and obligations related to employee benefits, and the fair value of derivative financial instruments. Further changes in the economic environment surrounding Honda, effects by market conditions, effects of currency fluctuations or other factors have combined to increase the uncertainty inherent in such estimates and assumptions. Actual results could differ from those estimates.
	(e) Revenue Recognition
	Sales of manufactured products are recognized when persuasive evidence of an arrangement exists, delivery has occurred, title and risk of loss have passed to the customers, the sales price is fixed or determinable, and collectibility is probable.
	Honda provides dealer incentives passed on to the end customers generally in the form of below-market interest rate loans or lease programs. The amount of interest or lease subsidies paid is the difference between the amount offered to retail customers and the amount stemmed from a market-based interest or lease rate. Honda also provides dealer incentives retained by the dealer, which generally represent discounts provided from Honda to the dealers. These incentives are classified as a reduction of sales revenue as the consideration is paid in cash, because Honda does not receive an identifiable benefit in exchange for this consideration. The incentives are estimated and accrued at the time the product is sold to the dealer.
	Operating lease revenues are recorded on a straight-line basis over the term of the lease.
	Interest income from finance receivables is recognized using the interest method. Finance receivable origination fees and certain direct origination costs are deferred, and the net fee or cost is amortized using the interest method over the contractual life of the finance receivables.
	Taxes collected from customers and remitted to governmental authorities on revenue-producing transactions are accounted for on a net basis and therefore are excluded from revenues in the consolidated statements of income.
	(f) Cash Equivalents
	Honda considers all highly liquid debt instruments with original maturities of three months or less to be cash equivalents. Cash equivalents mainly consist of money market funds and certificates of deposit.
	(g) Inventories
	Inventories are stated at the lower of cost or market. Cost is determined principally on a first-in, first-out basis.
	(h) Investments in Securities
	Investments in securities consist of investment in affiliates and debt and equity securities.
	Investments in affiliates in which Honda has the ability to exercise significant influence over their operating and financial policies, but where Honda does not have a controlling financial interest are accounted for using the equity method. Differences between the cost of investments in affiliates and the amount of underlying equity of the affiliates principally represent investor level goodwill.
	Honda considers whether the fair value of any of its equity method investments have declined below their carrying value whenever adverse events or changes in circumstances indicate that recorded values may not be recoverable. If Honda considers any such decline to be other-than-temporary based on various factors, then a write-down will be recorded to estimated fair value.
	Honda classifies its debt and marketable equity securities into the following categories: available-for-sale, trading, or held-to-maturity. Debt securities classified as “held-to-maturity” securities are reported at amortized cost. Debt and marketable equity securities classified as “trading” securities are reported at fair value, with unrealized gains and losses included in earnings. Other debt and marketable equity securities are classified as “available-for-sale” securities and are reported at fair value, with unrealized gains or losses, net of deferred taxes included in accumulated other comprehensive income (loss) in the equity section of the consolidated balance sheets. The costs of available-for-sale securities sold are accounted for using the moving-average method. Honda did not hold any “trading” securities at March 31, 2013 and 2014.
	Honda periodically compares the fair value of debt and marketable equity securities with their cost basis. If the fair value of the securities has declined below the cost basis and such decline is judged to be other-than-temporary, Honda recognizes the impairment of the securities through a charge to income. The determination of other-than-temporary impairment is based upon an assessment of the facts and circumstances related to each investment security. In assessing impairment of securities, Honda considers the factors such as degree and period of the decline in fair value, financial position and results of operations of investees and forecast earnings based on market and economic trend in which the investees operate. Honda did not recognize significant impairment loss on investments in securities for the years ended March 31, 2012, 2013 and 2014.
	Non-marketable equity securities are carried at cost, and are examined for the possibility of impairment periodically.
	(i) Goodwill
	Goodwill, all of which is allocated to Honda’s reporting units, is not amortized but is tested for impairment at least annually. Honda performs its annual impairment review of goodwill at March 31, and when a triggering event occurs between annual impairment dates. For the years ended March 31, 2012, 2013 and 2014, Honda did not recognize any goodwill impairment losses.
	The carrying amount of goodwill at March 31, 2013 and 2014 was ¥10,296 million and ¥11,439 million, respectively and is included in other assets of the consolidated balance sheets.
	(j) Property on Operating Leases
	Property on operating leases is reported at cost, less accumulated depreciation. Depreciation of vehicles is generally provided on a straight-line basis to an estimated residual value over the lease term. The residual values of the vehicles related to operating leases are estimated by using the estimate of future used vehicle values, taking into consideration external industry data and our own historical experience.
	(k) Depreciation and Amortization
	Depreciation of property, plant and equipment is calculated principally by the straight line method based on estimated useful lives and salvage values of the respective assets.
	The estimated useful lives used in computing depreciation and amortization of property, plant and equipment are as follows:
	Asset	Life
	Buildings and structures		3 to 50 years
	Machinery and equipment		2 to 20 years
	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. In recent years, because sales of global strategic product models are increasing, Honda has been enhancing its production systems and the versatility of production equipment to have better flexibility to meet changes in global customer demand. Further, Honda has resumed more normalized capital expenditures which Honda had previously held down due to the financial crisis beginning in the fiscal year ended March 31, 2009. Effective April 1, 2012, Honda changed to the straight line method of depreciation because management believes it better reflects the future economic benefit from the usage of property, plant and equipment under this more flexible and versatile production arrangement. The effect of the change in depreciation method is recognized prospectively as a change in accounting estimate in accordance with the FASB Accounting Standards Codification (ASC) 250 “Accounting Changes and Error Corrections”.
	As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥56,300 million. Net income attributable to Honda Motor Co., Ltd. and Basic net income attributable to Honda Motor Co., Ltd. per common share for the year ended March 31, 2013 increased by approximately ¥35,746 million and ¥19.83, respectively.
	(l) Impairment of Long-Lived Assets to Be Held and Used and Long-Lived Assets to Be Disposed of
	Honda’s long-lived assets and identifiable intangible assets other than goodwill having finite useful lives are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of an asset to be held and used is measured by a comparison of the carrying amount of an asset to future net cash flows (undiscounted and without interest charges) expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets. Honda did not recognize any significant impairment losses on long-lived assets, excluding property on operating leases for the years ended March 31, 2012, 2013 and 2014.
	Assets to be disposed of by sale are reported at the lower of the carrying amount or estimated fair value less costs to sell.
	(m) Income Taxes
	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period that includes the enactment date.
	Honda recognizes in the consolidated financial statements the impact of a tax position, if any, based on the technical merits of the position, when that position is more likely than not to be sustained upon examination. Benefits from tax positions that meet the more likely than not recognition threshold are measured at the largest amount of benefit that is greater than 50 percent likely to be realized upon settlement. Honda accounts for interest and penalties related to the liability for unrecognized tax benefits as a component of income tax expense in the consolidated statements of income.
	(n) Product-Related Expenses
	Advertising and sales promotion costs are expensed as incurred. Advertising expenses were ¥195,284 million, ¥254,016 million and ¥297,514 million, for the years ended March 31, 2012, 2013 and 2014, respectively. Estimated costs related to product warranty are accrued at the time the products are sold to customers, or those costs for new warranty programs, including product recalls, are deemed to be probable and can be reasonably estimated. Estimated warranty expenses are provided based on historical warranty claim experience with consideration given to the expected level of future warranty costs as well as current information on repair costs. Included in warranty expenses accruals are costs for general warranties on vehicles Honda sells and costs for warranty programs, including product recalls.
	(o) Basic Net Income Attributable to Honda Motor Co., Ltd. per Common Share
	Basic net income attributable to Honda Motor Co., Ltd. per common share has been computed by dividing net income attributable to Honda Motor Co., Ltd. by the weighted average number of common shares outstanding during each year. The weighted average number of common shares outstanding for the years ended March 31, 2012, 2013 and 2014 was 1,802,300,720 shares, 1,802,298,819 shares and 1,802,294,383 shares, respectively. There were no potentially dilutive shares outstanding during the years ended March 31, 2012, 2013 or 2014.
	(p) Foreign Currency Translation and Transactions
	Foreign currency financial statement amounts are translated into Japanese yen on the basis of the year-end exchange rate for all assets and liabilities and the weighted average rate for the year for all income and expense amounts. The resulting translation adjustments are included in accumulated other comprehensive income (loss) in the equity section of the consolidated balance sheets.
	All revenues and expenses associated with foreign currencies are converted at the rates of exchange prevailing when such transactions occur and foreign currency receivables and payables are re-measured at the applicable exchange rates on the balance sheet date. Foreign currency translation and transaction gains or losses are included in other income (expenses)-other, net and these net gains or losses for each of the years in the three-year period ended March 31, 2014 are as follows:
	Yen (millions)
	2012	2013		2014
	¥  4,563	¥  36,794		¥  (6,461)
	The gains or losses on translation of receivables and payables dominated in foreign currencies intended to be hedged are presented on a net basis with derivative financial instruments (note 17).
	(q) Derivative Financial Instruments
	Honda has entered into foreign exchange agreements and interest rate agreements to manage currency and interest rate exposures. These instruments include foreign currency forward contracts, currency swap agreements, currency option contracts and interest rate swap agreements (notes 16 and 17).
Honda recognizes all derivative financial instruments at fair value in its consolidated balance sheets. Derivative asset and liability positions are presented net by counterparty on the consolidated balance sheets when valid master netting agreements exist and the other conditions set out in the FASB Accounting Standards Codification (ASC) 210-20 “Balance Sheet-Offsetting” are met.
The Company applies hedge accounting for certain foreign currency forward contracts related to forecasted foreign currency transactions between the Company and its subsidiaries. These are designated as cash flow hedges on the date derivative contracts are entered into. The Company has a documented currency rate risk management policy. In addition, it documents all relationships between derivative financial instruments designated as cash flow hedges and the relevant hedged items to identify the relationship between them. The Company assesses, both at the hedge’s inception and on an ongoing basis, whether the derivative financial instruments designated as cash flow hedge are highly effective to offset changes in cash flows of hedged items.
When it is determined that a derivative financial instrument is not highly effective as a cash flow hedge, when the hedged item matures, is sold or is terminated, or when it is identified that the forecasted transaction is no longer probable, the Company discontinues hedge accounting. To the extent derivative financial instruments are designated as cash flow hedges and have been assessed as being highly effective, changes in their fair value are recognized in other comprehensive income (loss). The amounts are reclassified into earnings in the period when forecasted hedged transactions affect earnings. When these cash flow hedges prove to be ineffective, changes in the fair value of the derivatives are immediately recognized in earnings.
Changes in the fair value of derivative financial instruments not designated as accounting hedges are recognized in earnings in the period of the change.
Honda does not hold any derivative financial instruments for trading purposes.
(r) Shipping and Handling Costs
Shipping and handling costs included in selling, general and administrative expenses for each of the years in the three-year period ended March 31, 2014 are as follows:
Yen (millions)
2012	2013		2014
¥ 155,276	¥160,843		¥180,554
(s) Asset Retirement Liability
Honda recognizes an asset retirement liability if the fair value of the obligation can be reasonably estimated. Asset retirement obligations include those for which an entity has a legal obligation to perform an asset retirement activity, however, the timing and (or) method of settling the obligation are conditional on a future event that may or may not be within the control of the entity.
(t) Adoption of New Accounting Pronouncements
In February 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2013-02 “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”. This amendment requires reporting entities to provide information about the amounts reclassified out of accumulated other comprehensive income by component, and to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income.
Honda adopted ASU 2013-02, effective April 1, 2013, and discloses in accompanying note 15 to consolidated financial statements. This adoption has no impact on the Honda’s financial position or results of operations.
(u) Impact on the Company’s Consolidated Financial Position or Results of Operations of the Floods in Thailand
In October 2011, Thailand suffered from severe floods that caused damage to inventories, and machinery and equipment of certain consolidated subsidiaries and affiliates of the Company. Accordingly, production activities in plant facilities at Honda and its affiliates had been temporarily affected by the floods for the year ended March 31, 2012.
Honda recognized ¥23,420 million of costs and expenses, of which ¥10,680 million is included in cost of sales and ¥12,740 million is included in selling, general and administrative expenses in the accompanying consolidated statements of income for the year ended March 31, 2012. These costs and expenses mainly consist of losses on damaged inventories of ¥7,330 million which is included in cost of sales, and losses on damaged property, plant and equipment of ¥7,654 million which is included in selling, general and administrative expenses.
In addition, Honda recognized insurance recoveries of ¥21,725 million and ¥16,278 million for the years ended March 31, 2012 and 2013, respectively, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income. Honda recognizes insurance recoveries in excess of the incurred losses when settlements with insurance companies are reached.
(v) New Accounting Pronouncements Not Yet Adopted
In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09 “Revenue from Contracts with Customers”, which amends the revenue recognition requirements in the FASB Accounting Standards Codification (ASC). This statement requires that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The statement shall be applied using one of two methods: retrospectively to each prior reporting period presented, or retrospectively with the cumulative effect of initially applying this statement recognized at the date of initial application. The Company has not yet determined which method it will apply. This statement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. Honda is currently evaluating the impact of this statement on the Company’s consolidated financial position or results of operations.

Finance_Income_and_Related_Cos

Finance Income and Related Costs of Finance Subsidiaries	12 Months Ended
	Mar. 31, 2014
Finance Income and Related Costs of Finance Subsidiaries	'
	(2) Finance Income and Related Costs of Finance Subsidiaries
	Net sales and other operating revenue and cost of sales include finance income and related costs of finance subsidiaries for each of the years in the three-year period ended March 31, 2014 as follows:
		Yen (millions)
		2012		2013		2014
	Finance income	¥	526,576	¥	560,256	¥	708,588
	Finance costs		293,216		336,203		440,148

Finance_Receivables

Finance Receivables	12 Months Ended
	Mar. 31, 2014
Finance Receivables	'
	(3) Finance Receivables
	The finance subsidiaries of the Company provide retail lending and leasing to customers and wholesale financing to dealers primarily to support sales of our products. Honda classifies retail and direct financing lease receivables (consumer finance receivables) derived from those services as finance subsidiaries-receivables. Operating leases are classified as property on operating leases. Certain finance receivables related to sales of inventory are included in trade accounts and notes receivable and other assets in the consolidated balance sheets.
	Finance subsidiaries-receivables, net, consisted of the following at March 31, 2013 and 2014:
			Yen (millions)
			2013			2014
	Retail		¥	3,865,430		¥	4,678,741
	Direct financing lease			448,672			422,936
	Wholesale flooring			389,562			434,219
	Commercial loans			42,433			63,176
	Total finance receivables			4,746,097			5,599,072
	Less:
	Allowance for credit losses			19,716			24,851
	Allowance for losses on lease residual values			3,354			2,131
	Unearned interest income and fees			18,697			38,093
				4,704,330			5,533,997
	Less:
	Finance receivables included in trade accounts and notes receivables, net			461,450			498,230
	Finance receivables included in other assets, net			211,743			253,999
	Finance subsidiaries-receivables, net			4,031,137			4,781,768
	Less current portion			1,243,002			1,464,215
	Noncurrent finance subsidiaries-receivables, net		¥	2,788,135		¥	3,317,553
	Allowance for credit losses
	The majority of the credit risk is with consumer financing and to a lesser extent with dealer financing. Credit risk is affected by general economic conditions. The allowance for credit losses is management’s estimate of probable losses incurred on finance receivables.
	Consumer finance receivables are collectively evaluated for impairment. Delinquencies and losses are continuously monitored and this historical experience provides the primary basis for estimating the allowance. Various methodologies are utilized when estimating the allowance for credit losses including models that incorporate vintage loss and delinquency migration analysis. The models take into consideration attributes of the portfolio including loan-to-value ratios, internal and external credit scores, and collateral types. Economic factors such as used vehicle prices, unemployment rates, and consumer debt service burdens are also incorporated when estimating losses.
	Wholesales receivables are individually evaluated for impairment when specifically identified as impaired. Wholesales receivables are considered to be impaired when it is probable that our finance subsidiaries will be unable to collect all amounts due according to the original terms of the loan. The determination of whether dealer loans are impaired is based on evaluations of dealerships’ payment history, financial condition and cash flows, and their ability to perform under the terms of the loans. Dealer loans that have not been specifically identified as impaired are collectively evaluated for impairment.
	Honda regularly reviews the adequacy of the allowance for credit losses. The estimates are based on information available as of each reporting date. However, actual losses may differ from the original estimates as a result of actual results varying from those assumed in our estimates with inherently uncertain items.
	The following tables present the changes in the allowance for credit losses on finance receivables for the years ended March 31, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2013		Retail			Direct			Wholesale			Total
						financing lease
	Balance at beginning of year		¥	20,497		¥	1,151		¥	1,401		¥	23,049
	Provision			8,707			392			59			9,158
	Charge-offs			(20,838	)		(940	)		(289	)		(22,067	)
	Recoveries			8,143			117			16			8,276
	Adjustments from foreign currency translation			1,134			69			97			1,300
	Balance at end of year		¥	17,643		¥	789		¥	1,284		¥	19,716
			Yen (millions)
	For the year ended March 31, 2014		Retail			Direct			Wholesale			Total
						financing lease
	Balance at beginning of year		¥	17,643		¥	789		¥	1,284		¥	19,716
	Provision			18,616			310			1,484			20,410
	Charge-offs			(27,550	)		(573	)		(425	)		(28,548	)
	Recoveries			11,676			93			11			11,780
	Adjustments from foreign currency translation			1,252			17			224			1,493
	Balance at end of year		¥	21,637		¥	636		¥	2,578		¥	24,851
	In the finance subsidiaries of the Company in North America, retail and direct financing lease receivables are charged off when they become 120 days past due or earlier if they have been specifically identified as uncollectible. Wholesale receivables are charged off when they have been individually identified as uncollectible. In the finance subsidiaries of the Company in other areas except for North America, finance receivables are charged off when they have been identified as substantially uncollectible according to the internal standards of each subsidiary.
	Allowance for losses on lease residual values
	Finance subsidiaries of the Company purchase insurance to cover a substantial amount of the estimated residual value of vehicles leased as direct financing leases to customers. The allowance for losses on lease residual values is maintained at an amount management deems adequate to cover estimated losses on the uninsured portion of the vehicles’ lease residual values. The allowance is also based on management’s evaluation of many factors, including current economic conditions, industry experience and the finance subsidiaries’ historical experience with residual value losses.
	Delinquencies
	In the finance subsidiaries of the Company in North America, retail and direct financing lease receivables are considered delinquent if more than 10% of a monthly scheduled payment is contractually past due on a cumulative basis. Wholesale receivables are considered delinquent when any principal payments are past due. In the finance subsidiaries of the Company in other areas except for North America, finance receivables are considered delinquent when any principal payments are past due.
	The following tables present an age analysis of past due finance receivables at March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		30-59 days			60-89 days			90 days and			Total			Current*		Total finance
			past due			past due			greater			past due					receivables
									past due
	Retail
	New auto		¥	12,947		¥	1,805		¥	2,607		¥	17,359		¥	3,247,241	¥	3,264,600
	Used & certified auto			5,064			643			276			5,983			434,183		440,166
	Others			1,213			419			1,353			2,985			157,679		160,664
	Total retail			19,224			2,867			4,236			26,327			3,839,103		3,865,430
	Direct financing lease			966			161			1,644			2,771			445,901		448,672
	Wholesale
	Wholesale flooring			205			67			311			583			388,979		389,562
Commercial loans			—			—			—			—			42,433		42,433
Total wholesale			205			67			311			583			431,412		431,995
Total finance receivables		¥	20,395		¥	3,095		¥	6,191		¥	29,681		¥	4,716,416	¥	4,746,097
		Yen (millions)
As of March 31, 2014		30-59 days			60-89 days			90 days and			Total			Current*		Total finance
		past due			past due			greater			past due					receivables
								past due
Retail
New auto		¥	15,948		¥	2,069		¥	2,745		¥	20,762		¥	4,044,290	¥	4,065,052
Used & certified auto			5,557			689			281			6,527			424,872		431,399
Others			1,239			507			1,800			3,546			178,744		182,290
Total retail			22,744			3,265			4,826			30,835			4,647,906		4,678,741
Direct financing lease			1,106			214			384			1,704			421,232		422,936
Wholesale
Wholesale flooring			526			227			758			1,511			432,708		434,219
Commercial loans			—			—			133			133			63,043		63,176
Total wholesale			526			227			891			1,644			495,751		497,395
Total finance receivables		¥	24,376		¥	3,706		¥	6,101		¥	34,183		¥	5,564,889	¥	5,599,072
*	Includes recorded investment of finance receivables that are less than 30 days past due.
Credit quality indicators
The collection experience of consumer finance receivables provides an indication of the credit quality of consumer finance receivables. The likelihood of accounts charging off becomes significantly higher once an account becomes 60 days delinquent. The table below segments the Company’s portfolio of consumer finance receivables between groups the Company considers to be performing and nonperforming. Accounts that are delinquent for 60 days or greater are included in the nonperforming group and all other accounts are considered to be performing.
The following tables present the balances of consumer finance receivables by this credit quality indicator at March 31, 2013 and 2014.
		Yen (millions)
As of March 31, 2013		Performing			Nonperforming			Total consumer
								finance
								receivables
Retail
New auto		¥	3,260,188		¥	4,412		¥	3,264,600
Used & certified auto			439,247			919			440,166
Others			158,892			1,772			160,664
Total retail			3,858,327			7,103			3,865,430
Direct financing lease			446,867			1,805			448,672
Total		¥	4,305,194		¥	8,908		¥	4,314,102
		Yen (millions)
As of March 31, 2014		Performing			Nonperforming			Total consumer
								finance
								receivables
Retail
New auto		¥	4,060,238		¥	4,814		¥	4,065,052
Used & certified auto			430,429			970			431,399
Others			179,983			2,307			182,290
Total retail			4,670,650			8,091			4,678,741
Direct financing lease			422,338			598			422,936
Total		¥	5,092,988		¥	8,689		¥	5,101,677
A credit quality indicator for wholesale receivables is the internal risk ratings for the dealerships. Dealerships are assigned an internal risk rating based primarily on their financial condition. At a minimum, risk ratings for dealerships are updated annually and more frequently for dealerships with weaker risk ratings. The table below presents outstanding wholesale receivables balances by the internal risk rating group. Group A includes the loans of dealerships with the highest credit quality characteristics in the strongest risk rating tier. Group B includes the loans of all remaining dealers and are considered to have weaker credit quality characteristics. Although the likelihood of losses can be higher for dealerships in Group B, the overall risk of losses is not considered to be significant.
The following tables present the balances of wholesale receivables by this credit quality indicator at March 31, 2013 and 2014.
		Yen (millions)
As of March 31, 2013		Group A			Group B			Total
Wholesale
Wholesale flooring		¥	236,203		¥	153,359		¥	389,562
Commercial loans			24,198			18,235			42,433
Total		¥	260,401		¥	171,594		¥	431,995
		Yen (millions)
As of March 31, 2014		Group A			Group B			Total
Wholesale
Wholesale flooring		¥	245,019		¥	189,200		¥	434,219
Commercial loans			36,364			26,812			63,176
Total		¥	281,383		¥	216,012		¥	497,395
Contractual maturities
The following schedule shows the contractual maturities of finance receivables for each of the five years following March 31, 2014 and thereafter:
Years ending March 31		Yen
		(millions)
2015		¥	1,992,551
2016			1,425,249
2017			1,020,626
2018			685,494
2019			356,586
After five years			118,566
			3,606,521
Total		¥	5,599,072
Other finance receivables
Except for the finance subsidiaries-receivables, the other finance receivables about which credit quality information and the allowance for credit losses are required to be disclosed of ¥37,274 million and ¥29,605 million are included in other current assets, investments and advances-other and other assets in the consolidated balance sheets at March 31, 2013 and 2014, respectively. Honda estimates, individually, the collectibility of the other finance receivables based on the financial condition of the debtor. The impaired finance receivables amounted to ¥19,562 million and ¥20,094 million at March 31, 2013 and 2014, respectively, for which the allowance for credit losses were ¥19,541 million and ¥19,996 million at March 31, 2013 and 2014, respectively.
Regarding the other finance receivables which are not impaired, there are no past due receivables.

Variable_Interest_Entities

Variable Interest Entities	12 Months Ended
	Mar. 31, 2014
Variable Interest Entities	'
	(4) Variable Interest Entities
	Honda considers its involvement with a variable interest entity (VIE) under the FASB Accounting Standards Codification (ASC) 810 “Consolidation”. This standard prescribes that the reporting entity shall consolidate a VIE as its primary beneficiary when it is deemed to have a controlling financial interest in a VIE, meeting both of the following characteristics:
		(a)	The power to direct the activities of a VIE that most significantly impact the VIE’s economic performance.
		(b)	The obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE.
	The finance subsidiaries of the Company periodically securitize for liquidity and funding purposes and transfer finance receivables to the trust which is newly established to issue asset-backed securities. The finance subsidiaries of the Company are deemed to have the power to direct the activities of these trusts that most significantly impact the trusts’ economic performance, as they retain servicing rights in all securitizations, and manage delinquencies and defaults of the underlying receivables. Furthermore, the finance subsidiaries of the Company are deemed to have the obligation to absorb losses of these trusts that could potentially be significant to these trusts, as they would absorb the majority of the expected losses of these trusts by retaining certain subordinated interests of these trusts. Therefore, the Company has consolidated these trusts, as it is deemed to have controlling financial interests in these trusts.
	The following table presents the balances of the assets and liabilities of consolidated VIEs at March 31, 2013 and 2014.
			Yen (millions)
			2013		2014
	Finance subsidiaries-receivables, net		¥	713,631	¥	872,621
	Restricted cash*1			20,885		27,468
	Other assets			1,545		1,462
	Total assets		¥	736,061	¥	901,551
	Secured debt*2		¥	718,980	¥	877,054
	Other liabilities			237		249
	Total liabilities		¥	719,217	¥	877,303
	*1	Restricted cash as collateral for the payment of the related secured debt obligation is included in other current assets and investment and advances-other on the consolidated balance sheets.
	*2	Secured debt is included in short-term, current portion of long-term and long-term debt on the consolidated balance sheets.
	The creditors of these trusts do not have recourse to the finance subsidiaries’ general credit with the exception of representations and warranties customary in the industry provided by the finance subsidiaries to these trusts.
	There is no VIE in which Honda holds a significant variable interest but is not the primary beneficiary as of March 31, 2013 and 2014.

Inventories

Inventories	12 Months Ended
	Mar. 31, 2014
Inventories	'
	(5) Inventories
	Inventories at March 31, 2013 and 2014 are summarized as follows:
		Yen (millions)
		2013		2014
	Finished goods	¥	726,034	¥	759,099
	Work in process		53,035		69,731
	Raw materials		436,352		474,065
	Total	¥	1,215,421	¥	1,302,895

Investments_in_and_Advances_to

Investments in and Advances to Affiliates	12 Months Ended
	Mar. 31, 2014
Investments in and Advances to Affiliates	'
	(6) Investments in and Advances to Affiliates
	The difference between the carrying amount of investments in affiliates and the amount of underlying equity is mainly investor level goodwill and recognizing of impairment losses. The amounts are not material as of March 31, 2013 and 2014.
	Investments in affiliates include equity securities which have quoted market values at March 31, 2013 and 2014 compared with related carrying amounts as follows:
		Yen (millions)
		2013				2014
	Carrying amounts	¥	175,420			¥	212,615
	Market values		220,221				242,671
	For the year ended March 31, 2013, Honda recognized impairment losses of ¥12,757 million, net of tax, on certain investments in affiliates which have quoted market values because of other-than-temporary declines in fair values below their carrying values. The fair values of the investments were based on quoted market prices. The impairment losses are included in equity in income of affiliates in the accompanying consolidated statement of income. For the year ended March 31, 2014, Honda did not recognize any significant impairment losses.
	Certain combined financial information in respect of affiliates accounted for under the equity method at March 31, 2013 and 2014, and for each of the years in the three-year period ended March 31, 2014 is shown below (note 21):
		Yen (millions)
	As of March 31, 2013	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Current assets	¥	228,358			¥	1,335,075	¥	25,438	¥	1,588,871
	Other assets, principally property, plant and equipment		134,901				1,137,654		27,219		1,299,774
	Total assets		363,259				2,472,729		52,657		2,888,645
	Current liabilities		149,033				1,013,565		8,358		1,170,956
	Other liabilities		10,075				242,194		2,979		255,248
	Total liabilities		159,108				1,255,759		11,337		1,426,204
	Equity	¥	204,151			¥	1,216,970	¥	41,320	¥	1,462,441
		Yen (millions)
	As of March 31, 2014	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Current assets	¥	258,565			¥	1,732,609	¥	26,185	¥	2,017,359
	Other assets, principally property, plant and equipment		126,888				1,212,313		30,450		1,369,651
	Total assets		385,453				2,944,922		56,635		3,387,010
	Current liabilities		168,060				1,337,236		10,111		1,515,407
	Other liabilities		12,849				226,822		2,972		242,643
	Total liabilities		180,909				1,564,058		13,083		1,758,050
	Equity	¥	204,544			¥	1,380,864	¥	43,552	¥	1,628,960
		Yen (millions)
	For the year ended March 31, 2012	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	888,914			¥	3,579,019	¥	23,934	¥	4,491,867
	Net income attributable to Honda’s affiliates		72,168				177,309		1,516		250,993
		Yen (millions)
	For the year ended March 31, 2013	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	891,343			¥	3,876,766	¥	25,918	¥	4,794,027
	Net income attributable to Honda’s affiliates		60,586				162,037		1,717		224,340
		Yen (millions)
	For the year ended March 31, 2014	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	1,070,837			¥	4,314,804	¥	27,578	¥	5,413,219
	Net income attributable to Honda’s affiliates		79,381				230,397		2,708		312,486
	Significant investments in affiliates accounted for under the equity method at March 31, 2013 and 2014 are shown below:
	Business	Company		Percentage ownership
	Motorcycle	P.T. Astra Honda Motor			50	%
	Automobile	Guangqi Honda Automobile Co., Ltd.			50	%
		Dongfeng Honda Automobile Co., Ltd.			50	%
		Dongfeng Honda Engine Co., Ltd.			50	%
	There are no equity method affiliates that are in Financial services business.
	Sales to affiliates by the Company and its subsidiaries and sales among such affiliates are made on the same basis as sales to unaffiliated parties.
	Honda’s equity in undistributed income of affiliates at March 31, 2013 and 2014 included in retained earnings was ¥376,888 million and ¥417,050 million, respectively.
	Trade receivables and trade payables include the following balances with affiliates at March 31, 2013 and 2014, and purchases and sales include the following transactions with affiliates for each of the years in the three-year period ended March 31, 2014. Honda mainly purchases materials, supplies and services from affiliates, and sells finished goods, parts used in its products, equipment and services to affiliates.
		Yen (millions)
		2013				2014
	Amounts due from	¥	160,470			¥	225,383
	Amounts due to		97,958				138,181
	Yen (millions)
	2012				2013		2014
Purchases from	¥	762,415			¥	789,261	¥	1,028,523
Sales to		561,426				636,299		786,802

Investments_and_AdvancesOther

Investments and Advances-Other	12 Months Ended
	Mar. 31, 2014
Investments and Advances-Other	'
	(7) Investments and Advances-Other
	Investments and advances at March 31, 2013 and 2014 consist of the following:
		Yen (millions)
		2013		2014
	Current
	Corporate debt securities	¥	1,553	¥	11,050
	Government bonds		—		2,000
	Local bonds		—		6,620
	Advances		926		1,028
	Certificates of deposit		1,550		1,558
	Other		10,846		15,012
	Total	¥	14,875	¥	37,268
	Investments and advances due within one year are included in other current assets in the consolidated balance sheets.
		Yen (millions)
		2013		2014
	Noncurrent
	Auction rate securities	¥	6,928	¥	6,999
	Marketable equity securities		117,110		138,476
	Corporate debt securities		1,505		8,542
	Government bonds		2,000		—
	Local bonds		9,499		15,850
	U.S. government agency debt securities		1,068		5,455
	Non-marketable equity securities accounted for under the cost method
	Non-marketable preferred stocks		969		969
	Other		10,780		10,316
	Guaranty deposits		20,210		18,742
	Advances		2,132		1,998
	Other		37,479		46,314
	Total	¥	209,680	¥	253,661
	Certain information with respect to available-for-sale securities and held-to-maturity securities at March 31, 2013 and 2014 are summarized below:
		Yen (millions)
		2013		2014
	Available-for-sale
	Cost	¥	49,990	¥	84,820
	Fair value		128,848		185,960
	Gross unrealized gains		80,453		101,917
	Gross unrealized losses		1,595		777
	Held-to-maturity
	Amortized cost	¥	16,511	¥	34,650
	Fair value		16,556		34,667
	Gross unrealized gains		45		17
	Gross unrealized losses		—		—
	Maturities of debt securities classified as available-for-sale at March 31, 2014 are as follows:
		Yen
		(millions)
	Due within one year	¥	2,676
	Due after one year through five years		12,968
	Due after five years through ten years		8,748
	Due after ten years		14,512
	Total	¥	38,904
	Maturities of debt securities classified as held-to-maturity at March 31, 2014 are as follows:
		Yen
		(millions)
	Due within one year	¥	22,378
	Due after one year through five years		476
	Due after five years through ten years		10,954
	Due after ten years		842
	Total	¥	34,650
	There were no significant realized gains and losses from available-for-sale securities included in other income (expenses) – other, net for the years ended March 31, 2012, 2013 and 2014.
	Gross unrealized losses on available-for-sale securities and fair value of the related securities, aggregated by length of time that individual securities have been in a continuous unrealized loss position at March 31, 2014 are as follows:
		Yen (millions)
		Fair		Unrealized
		value		losses
Less than 12 months	¥	8,877	¥	224
12 months or longer		7,351		553
Total	¥	16,228	¥	777
Honda does not believe the decline in fair value of any of its investment securities to be other than temporary, based on factors such as financial and operating conditions of the issuer, the industry in which the issuer operates, degree and period of the decline in fair value and other relevant factors.
There were no held-to-maturity securities in a loss position at March 31, 2014.

Property_on_Operating_Leases

Property on Operating Leases	12 Months Ended
	Mar. 31, 2014
Property on Operating Leases	'
	(8) Property on Operating Leases
	Future minimum lease rentals expected to be received from property on operating leases at March 31, 2014 are as follows:
	Years ending March 31	Yen
		(millions)
	2015	¥	380,146
	2016		247,759
	2017		89,967
	2018		9,148
	2019		2,058
	Total future minimum lease rentals	¥	729,078
	Future minimum lease rentals as shown above should not necessarily be considered indicative of future cash collections.

Shortterm_and_Longterm_Debt

Short-term and Long-term Debt	12 Months Ended
	Mar. 31, 2014
Short-term and Long-term Debt	'
	(9) Short-term and Long-term Debt
	Short-term debt at March 31, 2013 and 2014 is as follows:
		Yen (millions)
		2013		2014
	Short-term bank loans	¥	347,842	¥	373,610
	Asset-backed notes		37,448		69,032
	Medium-term notes		159,963		231,519
	Commercial paper		693,044		645,183
	Total	¥	1,238,297	¥	1,319,344
	The weighted average interest rates on short-term debt outstanding at March 31, 2013 and 2014 were 0.86% and 1.15%, respectively.
	Long-term debt at March 31, 2013 and 2014 is as follows:
		Yen (millions)
		2013		2014
	Honda Motor Co., Ltd.:
	Loans, maturing through 2031:
	Unsecured, principally from banks	¥	160	¥	128
			160		128
	Subsidiaries:
	Loans, maturing through 2029:
	Secured, principally from banks		15,830		30,466
	Unsecured, principally from banks		1,043,857		1,224,947
	Asset-backed notes, maturing through 2019		681,020		808,022
	1.31% Japanese yen unsecured bond due 2013		40,000		—
	1.05% Japanese yen unsecured bond due 2014		30,000		30,000
	0.56% Japanese yen unsecured bond due 2015		30,000		30,000
	0.59% Japanese yen unsecured bond due 2015		30,000		30,000
	0.47% Japanese yen unsecured bond due 2016		40,000		40,000
	0.48% Japanese yen unsecured bond due 2017		40,000		40,000
	0.37% Japanese yen unsecured bond due 2017		30,000		30,000
	0.35% Japanese yen unsecured bond due 2017		35,000		35,000
	0.27% Japanese yen unsecured bond due 2018		30,000		30,000
	0.55% Japanese yen unsecured bond due 2018		—		50,000
	0.32% Japanese yen unsecured bond due 2018		—		40,000
	0.25% Japanese yen unsecured bond due 2019		—		40,000
	0.59% Japanese yen unsecured bond due 2019		10,000		10,000
	0.56% Japanese yen unsecured bond due 2019		15,000		15,000
	0.55% Japanese yen unsecured bond due 2020		10,000		10,000
	0.49% Japanese yen unsecured bond due 2020		—		10,000
	0.43% Japanese yen unsecured bond due 2021		—		10,000
	Medium-term notes, maturing through 2023		1,580,951		2,030,968
	Less unamortized discount, net		5,927		7,001
			3,655,731		4,537,402
	Total long-term debt		3,655,891		4,537,530
	Less current portion		945,046		1,303,464
	Total long-term debt, excluding current portion	¥	2,710,845	¥	3,234,066
	Pledged assets at March 31, 2013 and 2014 are as follows:
		Yen (millions)
		2013		2014
	Trade accounts and notes receivable	¥	25,528	¥	31,318
	Inventories		11,154		12,908
	Property, plant and equipment		26,169		58,504
	Finance subsidiaries-receivables		724,399		883,776
	Certain loans are secured by trade accounts and notes receivable, inventories and property, plant and equipment presented above and subject to collateralization upon request, and their interest rates range from 0.45% to 12.50% per annum at March 31, 2014 and weighted average interest rates on total outstanding long-term debt at March 31, 2013 and 2014 were 1.82% and 1.71%, respectively. Asset-backed notes are secured by finance subsidiaries-receivables, and their weighted average interest rates at March 31, 2013 and 2014 were 0.89% and 0.70%, respectively. Medium-term notes are unsecured, and their interest rates range from 0.38% to 5.03% at March 31, 2013 and from 0.22% to 7.63% at March 31, 2014.
	The following schedule shows the maturities of long-term debt for each of the five years following March 31, 2014 and thereafter:
	Years ending March 31	Yen
		(millions)
	2015	¥	1,303,464
	2016		963,462
	2017		1,125,196
	2018		391,004
	2019		460,730
	After five years		293,674
			3,234,066
Total	¥	4,537,530
Certain of the Company’s subsidiaries have entered into currency swap and interest rate swap agreements for hedging currency and interest rate exposures resulting from the issuance of long-term debt. Fair value of contracts related to currency swaps and interest rate swaps is included in other assets and other current assets and/or liabilities in the consolidated balance sheets, as appropriate (notes 16 and 17).
At March 31, 2014, Honda had unused line of credit facilities amounting to ¥2,718,969 million, of which ¥727,803 million related to commercial paper programs and ¥1,991,166 million related to medium-term notes programs. Honda is authorized to obtain financing at prevailing interest rates under these programs.
At March 31, 2014, the Company and its finance subsidiaries also had committed lines of unused credit amounting to ¥1,024,274 million. Within these lines, the unused committed lines supporting the commercial paper programs are ¥965,066 million. Borrowings under those committed lines of credit generally are available at the prime interest rate.
As is customary in Japan, both short-term and long-term bank loans are made under general agreements which provide that security and guarantees for present and future indebtedness will be given upon request of the bank, and that the bank shall have the right to offset cash deposits against obligations that have become due or, in the event of default, against all obligations due to the bank. Certain debenture trust agreements provide that Honda must give additional security upon request of the trustee.

Other_Liabilities

Other Liabilities	12 Months Ended
	Mar. 31, 2014
Other Liabilities	'
	(10) Other Liabilities
	Other liabilities at March 31, 2013 and 2014 consist of the following:
		Yen (millions)
		2013		2014
	Accrued liabilities for product warranty, excluding current portion	¥	104,584	¥	114,927
	Pension and other postretirement benefits		622,462		445,350
	Deferred income taxes		615,879		706,662
	Other		287,160		296,299
	Total	¥	1,630,085	¥	1,563,238

Income_Taxes

Income Taxes	12 Months Ended
	Mar. 31, 2014
Income Taxes	'
	(11) Income Taxes
	Total income tax expense (benefit) for each of the years in the three-year period ended March 31, 2014 are allocated as follows:
			Yen (millions)
			2012			2013			2014
	Income from continuing operations		¥	135,735		¥	178,976		¥	252,662
	Other comprehensive income (loss) (note 15)			(20,701	)		252			72,486
	Total		¥	115,034		¥	179,228		¥	325,148
	Income (loss) before income taxes and equity in income of affiliates by Japanese and foreign source for each of the years in the three-year period ended March 31, 2014 consisted of the following:
			Yen (millions)
			2012			2013			2014
	Income (loss) before income taxes
	Japanese		¥	(125,787	)	¥	50,450		¥	214,698
	Foreign			383,190			438,441			514,242
	Total		¥	257,403		¥	488,891		¥	728,940
	Income tax expense (benefit) for each of the years in the three-year period ended March 31, 2014 consisted of the following:
			Yen (millions)
			2012			2013			2014
	Income taxes
	Current
	Japanese		¥	8,136		¥	(3,666	)	¥	(794	)
	Foreign			77,938			129,390			208,030
	Total		¥	86,074		¥	125,724		¥	207,236
	Deferred
	Japanese		¥	(26,071	)	¥	21,977		¥	54,622
	Foreign			75,732			31,275			(9,196	)
	Total		¥	49,661		¥	53,252		¥	45,426
	Total
	Japanese		¥	(17,935	)	¥	18,311		¥	53,828
	Foreign			153,670			160,665			198,834
	Total		¥	135,735		¥	178,976		¥	252,662
	The statutory income tax rate in Japan for the years ended March 31, 2012, 2013 and 2014 was 40.0%, 37.9% and 37.9%, respectively. The foreign subsidiaries are subject to taxes based on income at rates ranging from 16.0% to 38.0%.
	The effective income tax rate for Honda for each of the years in the three-year period ended March 31, 2014 differs from the Japanese statutory income tax rate for the following reasons:
			2012			2013			2014
	Statutory income tax rate			40	%		37.9	%		37.9	%
	Recognition of valuation allowance			7.2			2.2			2.3
	Difference in statutory tax rates of foreign subsidiaries			(12.2	)		(6.7	)		(8.1	)
	Reversal of valuation allowance			(1.8	)		(1.5	)		(0.8	)
	Research and development credit			(0.6	)		(0.7	)		(0.9	)
	Dividend and royalty income from subsidiaries and affiliates, net of foreign tax credit			9.8			4.4			4.7
	Undistributed earnings of subsidiaries and affiliates			2.7			1.8			2
	Other adjustments relating to prior years			0.4			(1.5	)		0.4
	Adjustments for unrecognized tax benefits			(1.1	)		0.2			(3.9	)
	Adjustments for the change in income tax laws*			8.3			0.5			1.2
	Other			0			0			(0.1	)
	Effective tax rate			52.7	%		36.6	%		34.7	%
	*	On November 30, 2011, the National Diet of Japan approved the laws for amendments to previous income tax laws. Upon the change in the laws, the statutory income tax rate in Japan for the year ended March 31, 2013 was changed to 37.9%. The tax rate will be changed to 35.1% for fiscal years beginning on or after April 1, 2015. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net deferred tax assets decreased ¥16,072 million, and income tax expenses increased ¥16,072 million, as of the enactment date of the laws. This impact is included in Adjustments for the change in income tax laws for the year ended March 31, 2012. The impact for the year ended March 31, 2013 is not material.
		On March 20, 2014, the National Diet of Japan approved amendments to existing income tax laws and the Special Reconstruction Corporation Tax imposed on companies will be abolished for fiscal years beginning on or after April 1, 2014. Upon the change in the laws, the statutory income tax rate in Japan for fiscal years beginning on or after April 1, 2014 will be changed to approximately 35%. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net of deferred tax assets decreased ¥7,321 million, and income tax expenses increased ¥7,321 million, as of the enactment date of the laws.
	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at March 31, 2013 and 2014 are presented below:
			Yen (millions)
			2013			2014
	Deferred tax assets:
	Inventories		¥	28,122		¥	30,190
	Allowance for dealers and customers			87,224			110,936
	Accrued bonus			32,380			32,837
	Property, plant and equipment			65,397			58,671
	Operating loss carryforwards			138,559			107,269
	Pension and other postretirement benefits			229,102			152,409
	Other			166,894			188,057
	Total gross deferred tax assets			747,678			680,369
	Less valuation allowance			81,007			97,138
	Net deferred tax assets			666,671			583,231
	Deferred tax liabilities:
	Inventories			(16,575	)		(13,924	)
Prepaid pension expenses			(12,274	)		(4,977	)
Property, plant and equipment, excluding lease transactions			(80,103	)		(78,898	)
Direct financing lease transactions			(23,580	)		(26,658	)
Operating lease transactions			(623,535	)		(695,507	)
Undistributed earnings of subsidiaries and affiliates			(89,126	)		(112,085	)
Net unrealized gains on available-for-sale securities			(27,042	)		(33,709	)
Other			(51,727	)		(44,887	)
Total gross deferred tax liabilities			(923,962	)		(1,010,645	)
Net deferred tax asset (liability)		¥	(257,291	)	¥	(427,414	)
Deferred income tax assets and liabilities at March 31, 2013 and 2014 are reflected in the consolidated balance sheets under the following captions:
		Yen (millions)
		2013			2014
Current assets-Deferred income taxes		¥	234,075		¥	202,123
Other assets			127,248			80,289
Other current liabilities			(2,735	)		(3,164	)
Other liabilities			(615,879	)		(706,662	)
Net deferred tax asset (liability)		¥	(257,291	)	¥	(427,414	)
In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income over the periods in which those temporary differences become deductible and operating loss carryforwards utilized. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods for which the deferred tax assets are deductible, management believes it is more likely than not that Honda will realize the benefits of these deductible differences and operating loss carryforwards, net of the existing valuation allowances at March 31, 2013 and 2014. The amount of the deferred tax asset considered realizable, however, could be significantly reduced in the near term if estimates of future taxable income during the carryforward period are reduced due to further changes in the economic environment surrounding Honda, effects by market conditions, effects of currency fluctuations or other factors. For the years ended March 31, 2012, 2013 and 2014, the net change in the total valuation allowance was an increase of ¥3,613 million, ¥11,915 million, and ¥16,131 million, respectively (note 20). The valuation allowance primarily relates to deferred tax assets associated with net operating loss carryforwards.
At March 31, 2014, Honda has operating loss and tax credit carryforwards for income tax purposes of ¥353,357 million and ¥34,578 million, respectively, which are available to offset future taxable income and income taxes, if any. Periods available to offset future taxable income and income taxes vary in each tax jurisdiction and range from one year to an indefinite period as follows:
		Yen
		(millions)
Operating loss carryforwards:
Within 1 year		¥	434
1 to 5 years			12,975
5 to 20 years			222,937
Indefinite periods			117,011
Total		¥	353,357
		Yen
		(millions)
Tax credit carryforwards:
Within 1 year		¥	37
1 to 5 years			17,146
5 to 20 years			17,076
Indefinite periods			319
Total		¥	34,578
At March 31, 2013 and 2014, Honda did not recognize deferred tax liabilities of ¥140,691 million and ¥195,476 million, respectively, for certain portions of the undistributed earnings of the Company’s foreign subsidiaries and foreign corporate joint ventures because such portions were considered indefinitely reinvested. Deferred tax liabilities will be recognized when Honda expects that it will realize those undistributed earnings in a taxable manner, such as through receipt of dividends or sale of the investment. At March 31, 2013 and 2014, the undistributed earnings not subject to deferred tax liabilities were ¥4,133,175 million and ¥4,284,270 million, respectively.
Honda’s unrecognized tax benefits totaled ¥43,627 million, ¥39,151 million and ¥6,983 million at March 31, 2012, 2013 and 2014, respectively. Of these amounts, the amounts that would impact Honda’s effective income tax rate, if recognized, are ¥32,460 million, ¥37,012 million and ¥5,362 million in fiscal years 2012, 2013 and 2014, respectively.
Recognized interest and penalties, net included in income tax expense for the years ended March 31, 2012, 2013 and 2014 were ¥513 million benefit, ¥764 million loss and ¥2,406 million benefit, respectively. Honda had recorded approximately ¥3,292 million and ¥1,235 million for accrued interest and accrued penalties at March 31, 2013 and 2014, respectively. Reconciliations of the beginning and ending amount of unrecognized tax benefits for the years ended March 31 are as follows:
		Yen (millions)
		2012			2013			2014
Balance at beginning of year		¥	46,265		¥	43,627		¥	39,151
Additions for tax positions related to the current year			2,910			—			—
Additions for tax positions of prior years			4,538			687			3,332
Reductions for tax positions of prior years*			(1,217	)		(7,855	)		(26,063	)
Settlements			(1,688	)		—			(3,808	)
Reductions for statute of limitations			(6,894	)		—			(6,909	)
Effect of exchange rate changes			(287	)		2,692			1,280
Balance at end of year		¥	43,627		¥	39,151		¥	6,983
*	Due to the Company’s remeasurement based on technical merits regarding transfer pricing matters of overseas transactions between the Company and foreign affiliates, the Company has decreased a portion of unrecognized tax benefits during the year ended March 31, 2014.
Tax liabilities associated with uncertain tax positions are primarily classified as other noncurrent liabilities, as Honda does not expect to pay cash or settle these positions within the next twelve months.
Honda has open tax years primarily from 2005 to 2014 with various significant tax jurisdictions including Japan (fiscal years 2008-2014), the United States (fiscal years 2005-2014), Canada, the United Kingdom, Germany, France, Belgium, Thailand, India, Brazil and Australia.
Honda is subject to income tax examinations in many tax jurisdictions. Tax examinations can involve complex issues and the resolution of issues may span multiple years, particularly if subject to negotiation or litigation. Although Honda believes its estimates of the total unrecognized tax benefits are reasonable, uncertainties regarding the final determination of income tax audit settlements and any related litigation could affect the amount of total unrecognized tax benefits in future periods.
It is difficult to estimate the timing and range of possible change related to uncertain tax positions, as finalizing audits with the relevant income tax authorities may involve formal administrative and legal proceedings. Accordingly, it is not possible to reasonably estimate the expected changes to the total unrecognized tax benefits over the next twelve months, although any settlements or statute expirations may result in a significant increase or decrease in the total unrecognized tax benefits, including those positions related to tax examinations being currently conducted.

Dividends_and_Legal_Reserves

Dividends and Legal Reserves	12 Months Ended
	Mar. 31, 2014
Dividends and Legal Reserves	'
	(12) Dividends and Legal Reserves
	The Company Law of Japan provides that earnings in an amount equal to 10% of dividends of retained earnings shall be appropriated as a capital surplus or a legal reserve on the date of distribution of retained earnings until an aggregated amount of capital surplus and legal reserve equals 25% of stated capital. Certain foreign subsidiaries are also required to appropriate their earnings to legal reserves under the laws of their respective countries.
	Dividends and appropriations to the legal reserves charged to retained earnings during the years in the three-year period ended March 31, 2014 represent dividends paid out during those years and the related appropriations to the legal reserves. Dividends per share were ¥60, ¥72 and ¥79 for the years ended March 31, 2012, 2013 and 2014, respectively. The accompanying consolidated financial statements do not include any accrued liabilities for the dividend of ¥22 per share aggregating to ¥39,650 million proposed and resolved in the general shareholders’ meeting held on June 13, 2014.

Pension_and_Other_Postretireme

Pension and Other Postretirement Benefits	12 Months Ended
	Mar. 31, 2014
Pension and Other Postretirement Benefits	'
	(13) Pension and Other Postretirement Benefits
	The Company and its subsidiaries have various pension plans covering substantially all of their employees in Japan and certain employees in foreign countries. Benefits under the plans are primarily based on the combination of years of service and compensation. The funding policy is to make periodic contributions as required by applicable regulations. Plan assets consist primarily of domestic and foreign equity and debt securities.
	In September 2013, certain consolidated subsidiaries in North America amended their existing defined benefit pension plans, effective January 1, 2014, to reduce the benefits in future periods for their employees on or after January 1, 2014.
	This plan amendment resulted in a reduction of the projected benefit obligation and recognition of the prior service benefit at the date of the plan amendment which is amortized over the average remaining service period from the date of the plan amendment. The consolidated subsidiaries also remeasured their projected benefit obligation and the fair value of related plan assets at the date of the plan amendment. The effects of the plan amendment and the remeasurement were recognized in other comprehensive income (loss), net of tax during the fiscal year ended March 31, 2014.
	Following this plan amendment, employees of these consolidated subsidiaries could elect to move from the existing defined benefit pension plans to a defined contribution pension plan on January 1, 2014. Consequently, certain employees elected to move to the defined contribution pension plan in October 2013, resulting in a curtailment in the existing defined benefit pension plans. As a result, Honda recognized ¥21,368 million of the prior service benefit included in accumulated other comprehensive income (loss) as a curtailment gain, of which ¥15,407 million is included in cost of sales and ¥5,961 million is included in selling, general and administrative expense in the accompanying consolidated statements of income for the fiscal year ended March 31, 2014. The consolidated subsidiaries also remeasured their projected benefit obligation and the fair value of plan assets in the existing defined benefit pension plans at the date of the curtailment. The effect of the remeasurement was recognized in other comprehensive income (loss), net of tax during the fiscal year ended March 31, 2014.
	Obligations and funded status
	Reconciliations of beginning and ending balances of the pension benefit obligations and the fair value of the plan assets are as follows:
			Yen (millions)
			Japanese plans						Foreign plans
			2013			2014			2013			2014
	Change in benefit obligations:
	Benefit obligations at beginning of year		¥	(1,193,566	)	¥	(1,283,216	)	¥	(536,064	)	¥	(685,155	)
	Service cost			(31,124	)		(33,701	)		(24,826	)		(27,342	)
	Interest cost			(23,871	)		(19,248	)		(26,107	)		(31,857	)
	Plan participants’ contributions			—			—			(26	)		(13	)
	Actuarial gain (loss)			(82,834	)		(4,833	)		(33,210	)		20,074
	Benefits paid			48,179			47,363			11,177			39,339
	Amendment			—			—			—			57,251
	Curtailment			—			—			—			1,084
	Foreign currency translation			—			—			(76,099	)		(63,053	)
	Benefit obligations at end of year			(1,283,216	)		(1,293,635	)		(685,155	)		(689,672	)
	Change in plan assets:
	Fair value of plan assets at beginning of year			801,701			918,518			422,500			543,164
	Actual return on plan assets			94,446			71,304			45,124			67,666
	Employer contributions			70,550			69,580			23,795			33,557
	Plan participants’ contributions			—			—			26			13
	Benefits paid			(48,179	)		(47,363	)		(11,177	)		(39,339	)
	Foreign currency translation			—			—			62,896			51,891
	Fair value of plan assets at end of year			918,518			1,012,039			543,164			656,952
	Funded status		¥	(364,698	)	¥	(281,596	)	¥	(141,991	)	¥	(32,720	)
	Amounts recognized in the consolidated balance sheets consist of:
	Noncurrent assets		¥	1,480		¥	2,626		¥	—		¥	18,643
	Current liabilities			(364	)		(335	)		(38	)		(40	)
	Noncurrent liabilities			(365,814	)		(283,887	)		(141,953	)		(51,323	)
	Total		¥	(364,698	)	¥	(281,596	)	¥	(141,991	)	¥	(32,720	)
	Amounts recognized in accumulated other comprehensive income (loss) consist of:
	Actuarial loss (gain)		¥	394,998		¥	335,886		¥	206,941		¥	145,979
	Net transition obligation			—			—			77			35
	Prior service cost (benefit)			(121,671	)		(105,367	)		(1,905	)		(35,497	)
	Total		¥	273,327		¥	230,519		¥	205,113		¥	110,517
	Pension plans with accumulated benefit obligations in excess of plan assets:
	Projected benefit obligations		¥	(1,262,263	)	¥	(1,272,687	)	¥	(493,040	)	¥	(469,569	)
	Accumulated benefit obligations			(1,180,781	)		(1,191,640	)		(453,165	)		(469,152	)
	Fair value of plan assets			897,066			988,744			367,949			429,441
	The accumulated benefit obligations for all Japanese defined benefit plans at March 31, 2013 and 2014 were ¥1,197,913 million and ¥1,209,003 million, respectively. The accumulated benefit obligations for all foreign defined benefit plans at March 31, 2013 and 2014 were ¥610,517 million and ¥645,939 million, respectively.
	Components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss)
	Pension expense and other amounts recognized in other comprehensive income (loss) for each of the years in the three-year period ended March 31, 2014 include the following:
			Yen (millions)
			2012			2013			2014
	Japanese plans:
	Pension cost
	Service cost-benefits earned during the year		¥	33,454		¥	31,124		¥	33,701
	Interest cost on projected benefit obligations			23,481			23,871			19,248
	Expected return on plan assets			(23,645	)		(24,048	)		(25,341	)
	Amortization of actuarial loss (gain)			20,373			18,149			17,218
	Amortization of prior service cost (benefit)			(16,304	)		(16,304	)		(16,304	)
	Total		¥	37,359		¥	32,792		¥	28,522
	Other amounts recognized in other comprehensive income (loss)
	Actuarial loss (gain)		¥	(13,305	)	¥	10,137		¥	(41,894	)
	Amortization of actuarial loss (gain)			(20,373	)		(18,149	)		(17,218	)
	Amortization of prior service cost (benefit)			16,304			16,304			16,304
	Total			(17,374	)		8,292			(42,808	)
	Total recognized in pension cost and other comprehensive income (loss)		¥	19,985		¥	41,084		¥	(14,286	)
Foreign plans:
Pension cost
Service cost-benefits earned during the year		¥	19,506		¥	24,826		¥	27,342
Interest cost on projected benefit obligations			24,130			26,107			31,857
Expected return on plan assets			(26,796	)		(30,254	)		(39,624	)
Amortization of actuarial loss (gain)			5,829			10,724			12,538
Amortization of net transition obligation			30			33			42
Amortization of prior service cost (benefit)			6			(205	)		(2,291	)
Curtailment gain			—			—			(21,368	)
Other			3			17			—
Total		¥	22,708		¥	31,248		¥	8,496
Other amounts recognized in other comprehensive income (loss)
Actuarial loss (gain)		¥	71,160		¥	16,466		¥	(48,424	)
Amortization of actuarial loss (gain)			(5,829	)		(10,724	)		(12,538	)
Amortization of net transition obligation			(30	)		(33	)		(42	)
Prior service cost (benefit)			(2,677	)		41			(57,251	)
Amortization of prior service cost (benefit)			(6	)		205			2,291
Curtailment gain			—			—			21,368
Total			62,618			5,955			(94,596	)
Total recognized in pension cost and other comprehensive income (loss)		¥	85,326		¥	37,203		¥	(86,100	)
The following table presents the estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost over the next fiscal year.
		Yen (millions)
		Japanese			Foreign
		plans			plans
Amortization of actuarial loss (gain)		¥	13,451		¥	12,019
Amortization of net transition obligation			—			3
Amortization of prior service cost (benefit)			(16,304	)		(3,371	)
Assumptions
Weighted-average assumptions used to determine benefit obligation at March 31, 2013 and 2014 were as follows:
		2013			2014
Japanese plans:
Discount rate			1.5	%		1.5	%
Rate of salary increase			2.2	%		2.2	%
Foreign plans:
Discount rate			4.5 ~  4.7	%		4.6 ~  4.8	%
Rate of salary increase			2.5 ~  4.1	%		2.5 ~  3.9	%
Weighted-average assumptions used to determine net periodic benefit cost for each of the years in the three-year period ended March 31, 2014 were as follows:
		2012			2013			2014
Japanese plans:
Discount rate			2	%		2	%		1.5	%
Rate of salary increase			2.2	%		2.1	%		2.2	%
Expected long-term rate of return			3	%		3	%		3	%
Foreign plans:
Discount rate			5.5 ~ 6.0	%		4.6 ~ 5.2	%		4.5 ~ 4.7	%
Rate of salary increase			1.5 ~ 4.6	%		1.5 ~ 4.4	%		2.5 ~ 4.1	%
Expected long-term rate of return			6.5 ~ 7.5	%		6.2 ~ 7.7	%		6.0 ~ 7.4	%
Honda determines the expected long-term rate of return based on its investment policies. Honda considers the eligible investment assets under its investment policies, historical experience, expected long-term rate of return under the investment environment, and the long-term target allocations of the various asset categories.
Measurement date
Honda uses the balance sheet date as the measurement date for its plans.
Plan assets
Honda’s investment policies for the Japanese and foreign pension plan assets are designed to maximize total medium-to-long term returns that are available to provide future payments of pension benefits to eligible participants under accepted risks. Plan assets are invested in well-diversified Japanese and foreign individual equity and debt securities using the target asset allocations, consistent with accepted tolerance for risks. Honda sets target asset allocations for each asset category with future anticipated performance over medium-to-long term periods based on the expected returns, long-term risks and historical returns. Target asset allocations are adjusted as necessary when there are significant changes in the expected long-term returns of plan assets or the investment environment.
The following tables present the fair value of the Japanese pension plan assets by asset category as of March 31, 2013 and 2014.
		Yen (millions)
As of March 31, 2013		Level 1			Level 2			Level 3			Total
Cash and cash equivalents		¥	25,534		¥	—		¥	—		¥	25,534
Equity securities			312,764			263			—			313,027
Corporate bonds			4,320			5,477			18			9,815
Government, agency and local bonds			93,450			217,964			163			311,577
Group annuity insurance:
General accounts			—			21,042			—			21,042
Separate accounts			—			10,773			—			10,773
Pooled funds:
Hedge funds			—			—			85,391			85,391
Commingled and other mutual funds			2,033			135,619			1,213			138,865
Derivative instruments			81			2,413			—			2,494
Total		¥	438,182		¥	393,551		¥	86,785		¥	918,518
		Yen (millions)
As of March 31, 2014		Level 1			Level 2			Level 3			Total
Cash and cash equivalents		¥	20,438		¥	—		¥	—		¥	20,438
Equity securities			349,601			254			2			349,857
Corporate bonds			8,341			1,829			86			10,256
Government, agency and local bonds			256,114			107,491			—			363,605
Group annuity insurance:
General accounts			—			23,688			—			23,688
Separate accounts			—			11,625			—			11,625
Pooled funds:
Hedge funds			—			—			95,860			95,860
Commingled and other mutual funds			1,559			137,078			1,286			139,923
Derivative instruments			16			(3,229	)		—			(3,213	)
Total		¥	636,069		¥	278,736		¥	97,234		¥	1,012,039
*	Information about the three hierarchy levels is described in note 16.
The following tables present reconciliations during the years ended March 31, 2013 and 2014 for Level 3 Japanese pension plan assets.
		Yen (millions)
		Equity			Corporate			Government,			Pooled funds					Total
		securities			bonds			agency and
For the year ended March 31, 2013								local bonds			Hedge			Commingled
											funds			and other
														mutual
														funds
Balance at beginning of year		¥	180		¥	—		¥	100		¥	63,271		¥	—	¥	63,551
Actual return on plan assets:
Relating to assets still held at the reporting date			—			—			22			10,484			13		10,519
Relating to assets sold during the period			60			—			1			804			—		865
Purchases, sales and settlements, net			(240	)		18			40			10,832			1,200		11,850
Transfers in and/or out of Level 3			—			—			—			—			—		—
Balance at end of year		¥	—		¥	18		¥	163		¥	85,391		¥	1,213	¥	86,785
		Yen (millions)
		Equity			Corporate			Government,			Pooled funds					Total
		securities			bonds			agency and
For the year ended March 31, 2014								local bonds			Hedge			Commingled
											funds			and other
														mutual
														funds
Balance at beginning of year		¥	—		¥	18		¥	163		¥	85,391		¥	1,213	¥	86,785
Actual return on plan assets:
Relating to assets still held at the reporting date			—			4			—			9,600			73		9,677
Relating to assets sold during the period			—			—			3			644			—		647
Purchases, sales and settlements, net			2			64			(139	)		225			—		152
Transfers in and/or out of Level 3			—			—			(27	)		—			—		(27	)
Balance at end of year		¥	2		¥	86		¥	—		¥	95,860		¥	1,286	¥	97,234
The major valuation methodologies for Japanese pension plan assets are as follows:
Equity securities are mainly marketable securities and fair value is estimated using quoted market prices. Fair value measurement for equity securities is mainly classified as Level 1. At March 31, 2013 and 2014, this class includes approximately 10% and 8% of Japanese equity securities, 43% and 45% of United States equity securities and 47% and 47% of other foreign equity securities, respectively.
Fair value measurement for corporate, government, agency and local bonds, for which fair value is estimated using quoted market prices, is classified as Level 1. Fair value measurement for the assets of which fair value is estimated based on market observable inputs such as market interest rates and conditions of issuances is classified as Level 2. At March 31, 2013 and 2014, this class includes approximately 23% and 18% of Japanese bonds, 24% and 23% of United States bonds and 53% and 59% of other foreign bonds, respectively.
General accounts of group annuity insurance are assets invested by life insurance companies to meet fixed guaranteed rates of return for policyholders, and that life insurance companies bear the investment risk on such assets. Fair value of general accounts is estimated based on inputs such as contractual interest rates. Fair value measurement for general accounts is classified as Level 2. Separate accounts of group annuity insurance mainly consist of marketable equity securities and corporate, government, agency and local bonds traded in active markets. Honda estimates the fair value of the separate accounts based on their net asset values and Honda’s ownership percentage. Fair value measurement for separate accounts is classified as Level 2.
Hedge funds invest in various assets at the discretion of fund managers and their fair value is estimated based on prices using net asset value provided by the fund managers or third parties which include unobservable inputs in valuation. Fair value measurement for hedge funds is classified as Level 3. Hedge funds are diversely invested in various funds in order to avoid excessive concentration on investment portfolio. Commingled and other mutual funds are pooled funds which have underlying assets mainly consisting of marketable equity securities and corporate, government, agency and local bonds traded in active markets. Honda estimates the fair value of commingled and other mutual funds based on their net asset values and Honda’s ownership percentage. Fair value measurement for commingled and other mutual funds is mainly classified as Level 2.
Derivative instruments mainly consist of foreign exchange instruments and fair value of derivative instruments is estimated based on market observable inputs such as foreign exchange rates. Fair value measurement for derivative instruments is mainly classified as Level 2. At March 31, 2013 and 2014, on a gross basis, asset position is ¥6,623 million and ¥2,711 million and liability position is ¥4,129 million and ¥5,924 million, respectively.
The following tables present the fair value of the foreign pension plan assets by asset category as of March 31, 2013 and 2014.
		Yen (millions)
As of March 31, 2013		Level 1			Level 2			Level 3			Total
Cash and cash equivalents		¥	6,178		¥	—		¥	—		¥	6,178
Short-term investments			742			10,787			—			11,529
Equity securities			157,704			—			—			157,704
Corporate bonds			—			51,660			282			51,942
Government, agency and local bonds			2,868			42,416			373			45,657
Pooled funds:
Real estate funds			—			—			26,995			26,995
Private equity funds			—			—			22,946			22,946
Hedge funds			—			—			28,695			28,695
Commingled and other mutual funds			309			176,534			10,788			187,631
Derivative instruments			—			130			(73	)		57
Asset-backed securities			—			3,830			—			3,830
Total		¥	167,801		¥	285,357		¥	90,006		¥	543,164
		Yen (millions)
As of March 31, 2014		Level 1			Level 2			Level 3			Total
Cash and cash equivalents		¥	6,597		¥	—		¥	—		¥	6,597
Short-term investments			462			11,891			—			12,353
Equity securities			201,787			3,514			—			205,301
Corporate bonds			—			61,883			266			62,149
Government, agency and local bonds			4,170			54,136			49			58,355
Pooled funds:
Real estate funds			—			—			35,856			35,856
Private equity funds			—			—			33,215			33,215
Hedge funds			—			—			35,807			35,807
Commingled and other mutual funds			—			184,288			17,091			201,379
Derivative instruments			(704	)		1,475			(6	)		765
Asset-backed securities			—			5,175			—			5,175
Total		¥	212,312		¥	322,362		¥	122,278		¥	656,952
*	Information about the three hierarchy levels is described in note 16.
The following tables present reconciliations during the years ended March 31, 2013 and 2014 for Level 3 foreign pension plan assets.
		Yen (millions)
								Pooled funds
For the year ended March 31, 2013		Corporate			Government,			Real			Private			Hedge		Commingled			Derivative			Total
		bonds			agency and			estate			equity			funds		and other			instruments
					local bonds			funds			funds					mutual
																funds
Balance at beginning of year		¥	—		¥	—		¥	15,190		¥	10,030		¥	19,726	¥	1,840		¥	(28	)	¥	46,758
Actual return on plan assets:
Relating to assets still held at the reporting date			(2	)		7			1,010			898			1,537		606			2			4,058
Relating to assets sold during the period			11			7			(2	)		291			3		—			7			317
Purchases, sales and settlements, net			70			95			7,935			9,056			3,869		7,438			(45	)		28,418
Transfers in and/or out of Level 3			171			219			—			—			—		—			—			390
Foreign currency translation			32			45			2,862			2,671			3,560		904			(9	)		10,065
Balance at end of year		¥	282		¥	373		¥	26,995		¥	22,946		¥	28,695	¥	10,788		¥	(73	)	¥	90,006
		Yen (millions)
								Pooled funds
For the year ended March 31, 2014		Corporate			Government,			Real			Private			Hedge		Commingled			Derivative			Total
		bonds			agency and			estate			equity			funds		and other			instruments
					local bonds			funds			funds					mutual
																funds
Balance at beginning of year		¥	282		¥	373		¥	26,995		¥	22,946		¥	28,695	¥	10,788		¥	(73	)	¥	90,006
Actual return on plan assets:
Relating to assets still held at the reporting date			(12	)		2			2,403			1,778			3,217		353			—			7,741
Relating to assets sold during the period			(3	)		—			2			401			—		—			1			401
Purchases, sales and settlements, net			21			45			3,499			6,355			1,075		3,539			71			14,605
Transfers in and/or out of Level 3			(48	)		(397	)		—			—			—		—			—			(445	)
Foreign currency translation			26			26			2,957			1,735			2,820		2,411			(5	)		9,970
Balance at end of year		¥	266		¥	49		¥	35,856		¥	33,215		¥	35,807	¥	17,091		¥	(6	)	¥	122,278
The major valuation methodologies for foreign pension plan assets are as follows:
Fair value of short-term investments is mainly estimated based on market observable inputs. Fair value measurement for short-term investments is mainly classified as Level 2.
Equity securities are mainly marketable securities and their fair value is estimated using quoted market prices. Fair value measurement for equity securities is mainly classified as Level 1. At March 31, 2013 and 2014, this class includes approximately 6% and 5% of Japanese equity securities, 56% and 58% of United States equity securities and 38% and 37% of other foreign equity securities, respectively.
Fair value measurement for corporate, government, agency and local bonds of which fair value is estimated using quoted market prices is classified as Level 1. Fair value measurement for the assets of which fair value is estimated based on market observable inputs such as market interest rates and conditions of issuances is classified as Level 2. Fair value measurement for the assets of which fair value is estimated based on unobservable inputs provided by third parties is classified as Level 3.
Real estate funds invest in real estate mainly in the United States and the United Kingdom and their fair value is estimated based on prices using net asset value provided by the investment managers which include unobservable inputs in valuation. Fair value measurement for real estate funds is classified as Level 3. Fair value of private equity funds is estimated based on unobservable inputs such as proprietary models and uncorroborated data from the limited partnerships. Fair value measurement for private equity funds is classified as Level 3. Hedge funds invest in various assets at the discretion of fund managers and their fair value is estimated based on prices using net asset value provided by the fund managers or third parties which include unobservable inputs in valuation. Fair value measurement for hedge funds is classified as Level 3. Hedge funds are diversely invested in various funds in order to avoid excessive concentration on investment portfolios. Commingled and other mutual funds are pooled funds which have underlying assets mainly consisting of marketable equity securities and corporate, government, agency and local bonds traded in active markets. Honda estimates the fair value of commingled and other mutual funds based on their net asset values and Honda’s ownership percentage. Fair value measurement for commingled and other mutual funds is mainly classified as Level 2.
Fair value of asset-backed securities is mainly estimated based on market observable inputs provided by independent vendors. Fair value measurement for asset-backed securities is classified as Level 2.
Cash flows
Contributions
Honda expects to contribute ¥56,152 million to its Japanese pension plans and ¥23,088 million to its foreign pension plans in the year ending March 31, 2015.
Estimated future benefit payment
The following table presents estimated future gross benefit payments:
Years ending March 31		Yen (millions)
		Japanese			Foreign
		plans			plans
2015		¥	46,670		¥	23,297
2016			47,386			24,904
2017			48,683			26,797
2018			50,984			29,143
2019			53,616			32,020
2020-2024			298,741			198,433
Certain of the Company’s subsidiaries in North America provide mainly health care and life insurance benefits to retired employees. Such benefits have no material effect on Honda’s financial position and results of operations.
Special termination benefits
Yachiyo Industry Co., Ltd., which is a domestic consolidated subsidiary, implemented a special early retirement support plan in connection with the discontinuation of construction of a new auto plant resulting from the revision of Honda’s completed automobile production strategy for the year ended March 31, 2012. Honda recognized the cost related to this plan when the eligible employees decided to utilize the plan and the amount could be reasonably estimated. The cost of ¥10,354 million is included in selling, general and administrative expenses in the consolidated statement of income for the year ended March 31, 2012.

Supplemental_Disclosures_of_Ca

Supplemental Disclosures of Cash Flow Information	12 Months Ended
	Mar. 31, 2014
Supplemental Disclosures of Cash Flow Information	'
	(14) Supplemental Disclosures of Cash Flow Information
		Yen (millions)
		2012		2013		2014
	Cash paid (provided), net during the year for:
	Interest	¥	97,788	¥	86,989	¥	82,796
	Income taxes		47,217		138,583		240,668

Other_Comprehensive_Income_Los

Other Comprehensive Income (Loss)	12 Months Ended
	Mar. 31, 2014
Other Comprehensive Income (Loss)	'
	(15) Other Comprehensive Income (Loss)
	The following tables present the changes in accumulated other comprehensive income (loss) by component for the years ended March 31, 2012, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2012		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(1,268,233	)	¥	30,299		¥	(156	)	¥	(257,290	)	¥	(1,495,380	)
	Other comprehensive income (loss) before reclassifications			(118,135	)		6,351			(76	)		(46,543	)		(158,403	)
	Amounts reclassified from accumulated other comprehensive income (loss)			—			(539	)		47			6,890			6,398
	Net current-period other comprehensive income (loss)			(118,135	)		5,812			(29	)		(39,653	)		(152,005	)
	Less: Other comprehensive income attributable to noncontrolling interests			(1,323	)		(87	)		—			103			(1,307	)
	Balance at end of year		¥	(1,385,045	)	¥	36,198		¥	(185	)	¥	(297,046	)	¥	(1,646,078	)
			Yen (millions)
	For the year ended March 31, 2013		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(1,385,045	)	¥	36,198		¥	(185	)	¥	(297,046	)	¥	(1,646,078	)
	Other comprehensive income (loss) before reclassifications			430,812			7,968			(797	)		(24,534	)		413,449
	Amounts reclassified from accumulated other comprehensive income (loss)			—			16			745			9,237			9,998
	Net current-period other comprehensive income (loss)			430,812			7,984			(52	)		(15,297	)		423,447
	Less: Other comprehensive income attributable to noncontrolling interests			15,350			51			—			(1,240	)		14,161
	Balance at end of year		¥	(969,583	)	¥	44,131		¥	(237	)	¥	(311,103	)	¥	(1,236,792	)
			Yen (millions)
	For the year ended March 31, 2014		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(969,583	)	¥	44,131		¥	(237	)	¥	(311,103	)	¥	(1,236,792	)
	Other comprehensive income (loss) before reclassifications			333,022			15,975			(19	)		112,952			461,930
	Amounts reclassified from accumulated other comprehensive income (loss)			637			(723	)		256			(5,234	)		(5,064	)
	Net current-period other comprehensive income (loss)			333,659			15,252			237			107,718			456,866
	Less: Other comprehensive income attributable to noncontrolling interests			13,235			33			—			(180	)		13,088
	Balance at end of year		¥	(649,159	)	¥	59,350		¥	—		¥	(203,205	)	¥	(793,014	)
	The following table presents the reclassifications out of accumulated other comprehensive income (loss) by component for the year ended March 31, 2014.
	For the year ended March 31, 2014		Yen (millions)
	Details about accumulated other comprehensive income		Amounts reclassified			Affected line items in the statement where net
	(loss) components		from accumulated other			income is presented
			comprehensive income
			(loss)
	Adjustments from foreign currency translation
			¥	(1,027	)	Other income (expenses) – Other, net
				390		Income tax expense
			¥	(637	)	Net income
	Unrealized gains (losses) on available-for-sale securities, net
			¥	1,114		Other income (expenses) – Other, net
				(391	)	Income tax expense
			¥	723		Net income
	Unrealized gains (losses) on derivative instruments, net
			¥	(411	)	Other income (expenses) – Other, net
				155		Income tax expense
			¥	(256	)	Net income
	Pension and other postretirement benefits adjustments
			¥	8,823		*
				(3,589	)	Income tax expense
			¥	5,234		Net income
	Total reclassifications for the period		¥	5,064
	*	This accumulated other comprehensive income (loss) components is included in the computation of net periodic pension cost.
	The following tables present the tax effects allocated to each component of other comprehensive income (loss) and reclassification adjustments for the years ended March 31, 2012, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2012		Before-tax			Tax			Net-of-tax
						(expense)
or benefit
(note 11)
Adjustments from foreign currency translation:
Unrealized gains (losses) arising during the year		¥	(119,910	)	¥	1,775		¥	(118,135	)
Reclassification adjustments for losses (gains) realized in net income			—			—			—
Net unrealized gains (losses)			(119,910	)		1,775			(118,135	)
Unrealized gains (losses) on available-for-sale securities:
Unrealized holding gains (losses) arising during the year			9,438			(3,087	)		6,351
Reclassification adjustments for losses (gains) realized in net income			(706	)		167			(539	)
Net unrealized gains (losses)			8,732			(2,920	)		5,812
Unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses) arising during the year			(115	)		39			(76	)
Reclassification adjustments for losses (gains) realized in net income			78			(31	)		47
Net unrealized gains (losses)			(37	)		8			(29	)
Pension and other postretirement benefits adjustments*:
(Increase) decrease in net unrealized losses on pension and other postretirement benefits			(72,225	)		25,682			(46,543	)
Amortization of unrealized (gain) loss on pension and other postretirement benefits			10,734			(3,844	)		6,890
Net unrealized gains (losses)			(61,491	)		21,838			(39,653	)
Other comprehensive income (loss)		¥	(172,706	)	¥	20,701		¥	(152,005	)
		Yen (millions)
For the year ended March 31, 2013		Before-tax			Tax			Net-of-tax
					(expense)
					or benefit
					(note 11)
Adjustments from foreign currency translation:
Unrealized gains (losses) arising during the year		¥	433,640		¥	(2,828	)	¥	430,812
Reclassification adjustments for losses (gains) realized in net income			—			—			—
Net unrealized gains (losses)			433,640			(2,828	)		430,812
Unrealized gains (losses) on available-for-sales securities:
Unrealized holding gains (losses) arising during the year			12,336			(4,368	)		7,968
Reclassification adjustments for losses (gains) realized in net income			24			(8	)		16
Net unrealized gains (losses)			12,360			(4,376	)		7,984
Unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses) arising during the year			(1,281	)		484			(797	)
Reclassification adjustments for losses (gains) realized in net income			1,197			(452	)		745
Net unrealized gains (losses)			(84	)		32			(52	)
Pension and other postretirement benefits adjustments*:
(Increase) decrease in net unrealized losses on pension and other postretirement benefits			(36,611	)		12,077			(24,534	)
Amortization of unrealized (gain) loss on pension and other postretirement benefits			14,394			(5,157	)		9,237
Net unrealized gains (losses)			(22,217	)		6,920			(15,297	)
Other comprehensive income (loss)		¥	423,699		¥	(252	)	¥	423,447
		Yen (millions)
For the year ended March 31, 2014		Before-tax			Tax			Net-of-tax
					(expense)
					or benefit
					(note 11)
Adjustments from foreign currency translation:
Unrealized gains (losses) arising during the year		¥	343,695		¥	(10,673	)	¥	333,022
Reclassification adjustments for losses (gains) realized in net income			1,027			(390	)		637
Net unrealized gains (losses)			344,722			(11,063	)		333,659
Unrealized gains (losses) on available-for-sale securities:
Unrealized holding gains (losses) arising during the year			22,261			(6,286	)		15,975
Reclassification adjustments for losses (gains) realized in net income			(1,114	)		391			(723	)
Net unrealized gains (losses)			21,147			(5,895	)		15,252
Unrealized gains (losses) on derivative instruments:
Unrealized holding gains (losses) arising during the year			(29	)		10			(19	)
Reclassification adjustments for losses (gains) realized in net income			411			(155	)		256
Net unrealized gains (losses)			382			(145	)		237
Pension and other postretirement benefits adjustments*:
(Increase) decrease in net unrealized losses on pension and other postretirement benefits			171,924			(58,972	)		112,952
Amortization of unrealized (gain) loss on pension and other postretirement benefits			(8,823	)		3,589			(5,234	)
Net unrealized gains (losses)			163,101			(55,383	)		107,718
Other comprehensive income (loss)		¥	529,352		¥	(72,486	)	¥	456,866
*	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Mar. 31, 2014
Fair Value Measurements	'
	(16) Fair Value Measurements
	In accordance with the FASB Accounting Standards Codification (ASC) 820 “Fair Value Measurements and Disclosures”, Honda uses a three-level hierarchy when measuring fair value. The following is a description of the three hierarchy levels:
		Level 1	Quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date
		Level 2	Inputs other than quoted prices included within Level 1 that are observable for the assets or liabilities, either directly or indirectly
		Level 3	Unobservable inputs for the assets or liabilities
	The level in the fair value hierarchy within which a fair value measurement in its entirety falls is based on the lowest input that is significant to the fair value measurement in its entirety.
	The following tables present the assets and liabilities measured at fair value on a recurring basis as of March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Level 1			Level 2			Level 3			Gross			Netting			Net
												fair value			adjustment			amount
	Assets:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	6,538		¥	—		¥	6,538		¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			32,152			—			32,152			—			—
	Total derivative instruments			—			38,690			—			38,690			(18,071	)		20,619
	Available-for-sale securities
	Marketable equity securities			117,110			—			—			117,110			—			117,110
	Auction rate securities			—			—			6,928			6,928			—			6,928
	Debt securities			—			4,226			—			4,226			—			4,226
	Others			584			—			—			584			—			584
	Total available-for-sale securities			117,694			4,226			6,928			128,848			—			128,848
	Total		¥	117,694		¥	42,916		¥	6,928		¥	167,538		¥	(18,071	)	¥	149,467
	Liabilities:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	(78,934	)	¥	—		¥	(78,934	)	¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			(14,639	)		—			(14,639	)		—			—
	Total derivative instruments			—			(93,573	)		—			(93,573	)		18,071			(75,502	)
	Total		¥	—		¥	(93,573	)	¥	—		¥	(93,573	)	¥	18,071		¥	(75,502	)
			Yen (millions)
	As of March 31, 2014		Level 1			Level 2			Level 3			Gross			Netting			Net
												fair value			adjustment			amount
	Assets:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	11,036		¥	—		¥	11,036		¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			19,814			—			19,814			—			—
	Total derivative instruments			—			30,850			—			30,850			(10,804	)		20,046
	Available-for-sale securities
	Marketable equity securities			138,476			—			—			138,476			—			138,476
	Auction rate securities			—			—			6,999			6,999			—			6,999
	Debt securities			—			31,905			—			31,905			—			31,905
	Others			5,146			3,434			—			8,580			—			8,580
	Total available-for-sale securities			143,622			35,339			6,999			185,960			—			185,960
	Total		¥	143,622		¥	66,189		¥	6,999		¥	216,810		¥	(10,804	)	¥	206,006
	Liabilities:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	(14,852	)	¥	—		¥	(14,852	)	¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			(10,887	)		—			(10,887	)		—			—
	Total derivative instruments			—			(25,739	)		—			(25,739	)		10,804			(14,935	)
	Total		¥	—		¥	(25,739	)	¥	—		¥	(25,739	)	¥	10,804		¥	(14,935	)
	Derivative asset and liability positions are presented net by counterparty on the consolidated balance sheets when valid master netting agreement exists and the other conditions set out in ASC 210-20 “Balance Sheet-Offsetting” are met.
	The following tables present reconciliations during the years ended March 31, 2013 and 2014 for all Level 3 assets and liabilities measured at fair value on a recurring basis.
			Yen
			(millions)
	For the year ended March 31, 2013		Auction rate
			securities
	Balance at beginning of year		¥	6,651
	Total realized/unrealized gains or losses
	Included in earnings			—
	Included in other comprehensive income (loss)			115
	Purchases, issuances, settlements and sales
	Purchases			—
	Issuances			—
	Settlements			—
Sales			(691	)
Foreign currency translation			853
Balance at end of year		¥	6,928
The amounts of total gains or losses for the period attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date
Included in earnings		¥	—
Included in other comprehensive income (loss)			115
		Yen
		(millions)
For the year ended March 31, 2014		Auction rate
		securities
Balance at beginning of year		¥	6,928
Total realized/unrealized gains or losses
Included in earnings			—
Included in other comprehensive income (loss)			202
Purchases, issuances, settlements and sales
Purchases			—
Issuances			—
Settlements			—
Sales			(790	)
Foreign currency translation			659
Balance at end of year		¥	6,999
The amounts of total gains or losses for the period attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date
Included in earnings		¥	—
Included in other comprehensive income (loss)			103
The valuation methodologies for the assets and liabilities measured at fair value on a recurring basis are as follows:
Foreign exchange and interest rate instruments (notes 1(q) and 17)
The fair values of foreign currency forward exchange contracts and foreign currency option contracts are estimated by using market observable inputs such as spot exchange rates, discount rates and implied volatility. Fair value measurements for foreign currency forward exchange contracts and foreign currency option contracts are classified as Level 2. The fair values of currency swap agreements and interest rate swap agreements are estimated by discounting future cash flows using market observable inputs such as LIBOR rates, swap rates, and foreign exchange rates. Fair value measurements for these currency swap agreements and interest rate swap agreements are classified as Level 2.
The credit risk of Honda and its counterparties are considered in the valuation of foreign exchange and interest rate instruments.
Marketable equity securities
The fair value of marketable equity securities is estimated by using quoted market prices. Fair value measurement for marketable equity securities is classified as Level 1.
Auction rate securities
The subsidiary’s auction rate securities holdings were AAA rated and are insured by qualified guarantee agencies, and reinsured by the Secretary of Education and United States Government, and are guaranteed about 95% by the United States Government. To estimate fair value of auction rate securities, Honda uses a third-party-developed valuation model which obtains a wide array of market observable inputs, as well as unobservable inputs including probability of passing or failing auction at each auction. Fair value measurement for auction rate securities is classified as Level 3.
Debt securities
Debt securities consist mainly of corporate bonds and local bonds and the fair values are estimated based on proprietary pricing models provided by specialists and/or market makers and the models obtain a wide array of market observable inputs such as credit ratings and discount rates. Fair value measurement for debt securities is classified as Level 2.
For the year ended March 31, 2013, Honda measured certain investments in affiliates which have quoted market values at fair value on a nonrecurring basis due to the recognition of impairment loss (note 6). The fair value of the investments was ¥68,778 million and estimated by using quoted market prices. Fair value measurement for the investments is classified as Level 1.
Honda does not have significant assets and liabilities measured at fair value on a nonrecurring basis as of and for the year ended March 31, 2014.
Honda has not elected the fair value option for the fiscal years ended March 31, 2013 and 2014.
The estimated fair values of significant financial instruments at March 31, 2013 and 2014 are as follows:
		Yen (millions)
		2013						2014
		Carrying			Estimated			Carrying			Estimated
		amount			fair value			amount			fair value
Finance subsidiaries-receivables*		¥	4,278,460		¥	4,326,333		¥	5,140,064		¥	5,175,564
Held-to-maturity securities			16,511			16,556			34,650			34,667
Debt			(4,894,188	)		(4,966,318	)		(5,856,874	)		(5,917,087	)
*	The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table exclude ¥425,870 million and ¥393,933 million, respectively, of direct financing leases, net, classified as finance subsidiaries-receivables in the consolidated balance sheets. The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table also include ¥673,193 million and ¥752,229 million of finance receivables classified as trade accounts and notes receivable and other assets in the consolidated balance sheets, respectively.
The estimated fair values have been determined using relevant market information and appropriate valuation methodologies. However, these estimates are subjective in nature and involve uncertainties and matters of significant judgment and, therefore, cannot be determined with precision. The effect of using different assumptions and/or estimation methodologies may be significant to the estimated fair values.
The methodologies and assumptions used to estimate the fair values of financial instruments are as follows:
Cash and cash equivalents, trade receivables and trade payables
The carrying amounts approximate fair values because of the short maturity of these instruments.
Finance subsidiaries-receivables
The fair values of retail receivables and commercial loans are estimated by discounting future cash flows using the current rates for these instruments of similar remaining maturities. Given the short maturities of wholesale flooring receivables, the carrying amount of these receivables approximates fair value. Fair value measurements for retail receivables and commercial loans are mainly classified as Level 3.
Held-to-maturity securities
The fair value of Government bonds is estimated by using quoted market prices. Fair value measurement of those Government bonds is classified as Level 1. The fair values of corporate bonds and local bonds are estimated based on proprietary pricing models provided by specialists and/or market makers and the models obtain a wide array of market observable inputs such as credit ratings and discount rates. Fair value measurement for these securities is classified as Level 2.
Debt
The fair values of bonds are estimated by using quoted market prices. Fair value measurement of those bonds is mainly classified as Level 1. The fair values of short-term loans and long-term loans are estimated by discounting future cash flows using interest rates currently available for loans of similar terms and remaining maturities. Fair value measurements for these loans are mainly classified as Level 2.

Risk_Management_Activities_and

Risk Management Activities and Derivative Financial Instruments	12 Months Ended
	Mar. 31, 2014
Risk Management Activities and Derivative Financial Instruments	'
	(17) Risk Management Activities and Derivative Financial Instruments
	Honda uses derivative financial instruments in the normal course of business to reduce their exposure to fluctuations in foreign exchange rates and interest rates (notes 1(q) and 16). Currency swap agreements are used to manage currency risk exposure on foreign currency denominated debt. Foreign currency forward exchange contracts and purchased option contracts are used to hedge currency risk of sale commitments denominated in foreign currencies (principally U.S. dollars). Foreign currency written option contracts are entered into in combination with purchased option contracts to offset premium amounts to be paid for purchased option contracts. Interest rate swap agreements are mainly used to manage interest rate risk exposure and to convert floating rate financing, such as commercial paper, to (normally three-five years) fixed rate financing in order to match financing costs with income from finance receivables. These instruments involve, to varying degrees, elements of credit, exchange rate and interest rate risks in excess of the amount recognized in the consolidated balance sheets.
	The aforementioned instruments contain an element of risk in the event the counterparties are unable to meet the terms of the agreements. However, Honda minimizes the risk exposure by limiting the counterparties to major international banks and financial institutions meeting established credit guidelines. Management of Honda does not expect any counterparty to default on its obligations and, therefore, does not expect to incur any losses due to counterparty default. Honda currently does not require or place collateral for these financial instruments with any counterparties.
	Contract amounts outstanding for foreign currency forward exchange contracts, foreign currency option contracts and currency swap agreements and the notional principal amounts of interest rate swap agreements at March 31, 2013 and 2014 are as follows:
	Derivatives designated as hedging instruments
		Yen (millions)
		2013				2014
	Foreign currency forward exchange contracts	¥	23,324			¥	—
	Total foreign exchange instruments	¥	23,324			¥	—
	Derivatives not designated as hedging instruments
		Yen (millions)
		2013				2014
	Foreign currency forward exchange contracts	¥	724,435			¥	506,734
	Foreign currency option contracts		4,145				3,721
	Currency swap agreements		337,254				366,031
	Total foreign exchange instruments	¥	1,065,834			¥	876,486
	Interest rate swap agreements	¥	4,063,289			¥	4,809,037
	Total interest rate instruments	¥	4,063,289			¥	4,809,037
	Cash flow hedges
	The Company applies hedge accounting for certain foreign currency forward exchange contracts related to forecasted foreign currency transactions between the Company and its subsidiaries. Changes in the fair value of derivative financial instruments designated as cash flow hedges are recognized in other comprehensive income (loss). The amounts are reclassified into earnings in the same period when forecasted hedged transactions affect earnings. The amount recognized in accumulated other comprehensive income (loss) at March 31, 2013 was ¥237 million loss. The Company does not hold any derivative financial instruments designated as cash flow hedges and there is no amount recognized in accumulated other comprehensive income (loss) at March 31, 2014.
	The period that hedges the changes in cash flows related to the risk of foreign currency rate is at most around two months. There are no derivative financial instruments where hedge accounting has been discontinued due to the forecasted transaction no longer being probable. The Company excludes financial instruments’ time value component from the assessment of hedge effectiveness. There is no portion of hedging instruments that has been assessed ineffective.
	Derivative financial instruments not designated as accounting hedges
	Changes in the fair value of derivative financial instruments not designated as accounting hedges are recognized in earnings in the period of the change.
	The estimated fair values of derivative instruments at March 31, 2013 and 2014 are as follows.
	As of March 31, 2013
	Derivatives designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	—			¥	(211)			¥	—		¥	—		¥	(211)
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	6,538			¥	(78,723	)		¥	(1,534	)	¥	(314	)	¥	(70,337	)
	Interest rate instruments		32,152				(14,639	)			3,907			18,560			(4,954	)
	Total	¥	38,690			¥	(93,362	)		¥	2,373		¥	18,246		¥	(75,291	)
	Netting adjustment		(18,071	)			18,071
	Net amount	¥	20,619			¥	(75,291	)
	As of March 31, 2014
	Derivatives designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	—			¥	—			¥	—		¥	—		¥	—
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	11,036			¥	(14,852	)		¥	4,910		¥	2,288		¥	(11,014	)
	Interest rate instruments		19,814				(10,887	)			593			12,255			(3,921	)
	Total	¥	30,850			¥	(25,739	)		¥	5,503		¥	14,543		¥	(14,935	)
	Netting adjustment		(10,804	)			10,804
	Net amount	¥	20,046			¥	(14,935	)
	Derivative asset and liability positions are presented net by counterparty on the consolidated balance sheets when valid master netting agreement exists and the other conditions set out in the FASB Accounting Standards Codification (ASC) 210-20 “Balance Sheet-Offsetting” are met.
The pre-tax effects of derivative instruments on the Company’s results of operations for each of the years in the three-year period ended March 31, 2014 are as follows:
For the year ended March 31, 2012
Derivatives designated as hedging instruments
Cash flow hedges:
	Yen (millions)
	Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
	recognized in other				accumulated other comprehensive						earnings (financial
	comprehensive				income (loss) into earnings						instruments’ time value
	income (loss)				(effective portion)						component excluded from
	(effective portion)										the assessment of hedge effectiveness)
	Amount				Location		Amount				Location	Amount
Foreign exchange instruments	¥	-115			Other income		¥	-78			Other income	¥	-455
					(expenses) – Other, net						(expenses) – Other, net
Derivatives not designated as hedging instruments
	Yen (millions)
	Gain (Loss) recognized in earnings
	Location		Amount
Foreign exchange instruments	Other income (expenses) – Other, net		¥	(3,709	)
Interest rate instruments	Other income (expenses) –  Other, net			(1,421	)
Total			¥	(5,130	)
For the year ended March 31, 2013
Derivatives designated as hedging instruments
Cash flow hedges:
	Yen (millions)
	Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
	recognized in other				accumulated other comprehensive						earnings (financial
	comprehensive				income (loss) into earnings						instruments’ time value
	income (loss)				(effective portion)						component excluded from
	(effective portion)										the assessment of hedge effectiveness)
	Amount				Location		Amount				Location	Amount
Foreign exchange instruments	¥	-1,281			Other income		¥	-1,197			Other income	¥	-589
					(expenses) – Other, net						(expenses) – Other, net
Derivatives not designated as hedging instruments
	Yen (millions)
	Gain (Loss) recognized in earnings
	Location		Amount
Foreign exchange instruments	Other income (expenses) – Other, net		¥	(111,004	)
Interest rate instruments	Other income (expenses) – Other, net			3,212
Total			¥	(107,792	)
For the year ended March 31, 2014
Derivatives designated as hedging instruments
Cash flow hedges:
	Yen (millions)
	Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
	recognized in other				accumulated other comprehensive						earnings (financial
	comprehensive				income (loss) into earnings						instruments’ time value
	income (loss)				(effective portion)						component excluded from
	(effective portion)										the assessment of hedge effectiveness)
	Amount				Location		Amount				Location	Amount
Foreign exchange instruments	¥	-29			Other income		¥	-411			Other income	¥	-714
					(expenses) – Other, net						(expenses) – Other, net
Derivatives not designated as hedging instruments
	Yen (millions)
	Gain (Loss) recognized in earnings
	Location		Amount
Foreign exchange instruments	Other income (expenses) – Other, net		¥	(23,765	)
Interest rate instruments	Other income (expenses) – Other, net			(10,547	)
Total			¥	(34,312	)
The gains and losses are included in other income (expenses) – other, net on a net basis with related items, such as foreign currency translation (note 1(p)).

Commitments_and_Contingent_Lia

Commitments and Contingent Liabilities	12 Months Ended
	Mar. 31, 2014
Commitments and Contingent Liabilities	'
	(18) Commitments and Contingent Liabilities
	At March 31, 2014, Honda had commitments for purchases of property, plant and equipment and other commitments of approximately ¥131,238 million.
	Honda has entered into various guarantee and indemnification agreements. At March 31, 2013 and 2014, Honda has guaranteed ¥26,475 million and ¥25,368 million of bank loans of employees for their housing costs, respectively. If an employee defaults on his/her loan payments, Honda is required to perform under the guarantee. The undiscounted maximum amount of Honda’s obligation to make future payments in the event of defaults is ¥26,475 million and ¥25,368 million, respectively, at March 31, 2013 and 2014. At March 31, 2014, no amount has been accrued for any estimated losses under the obligations, as it is probable that the employees will be able to make all scheduled payments.
	Honda warrants its products for specific periods of time. Honda also provides specific warranty programs, including product recalls, as needed. Product warranties vary depending upon the nature of the product, the geographic location of its sale and other factors.
	The changes in the accrued liabilities for those product warranties for each of the years in the two-year period ended March 31, 2014 are as follows:
		Yen (millions)
		2013			2014
	Balance at beginning of year	¥	170,562		¥	208,033
	Warranty claims paid during the period		(64,942	)		(104,090	)
	Liabilities accrued for warranties issued during the period		97,108			153,898
	Changes in liabilities for pre-existing warranties during the period		(8,583	)		397
	Foreign currency translation		13,888			11,382
	Balance at end of year	¥	208,033		¥	269,620
	With respect to product liability, personal injury claims or lawsuits, Honda believes that any judgment that may be recovered by any plaintiff for general and special damages and court costs will be adequately covered by Honda’s insurance and accrued liabilities. Punitive damages are claimed in certain of these lawsuits. Honda is also subject to potential liability under other various lawsuits and claims. Honda recognizes an accrued liability for loss contingencies when it is probable that an obligation has been incurred and the amount of loss can be reasonably estimated. Honda reviews these pending lawsuits and claims periodically and adjusts the amounts recorded for these contingent liabilities, if necessary, by considering the nature of lawsuits and claims, the progress of the case and the opinions of legal counsel. After consultation with legal counsel, and taking into account all known factors pertaining to existing lawsuits and claims, Honda believes that the ultimate outcome of such lawsuits and pending claims should not result in liability to Honda that would be likely to have an adverse material effect on its consolidated financial position, results of operations or cash flows.

Leases

Leases	12 Months Ended
	Mar. 31, 2014
Leases	'
	(19) Leases
	Honda is the lessee under several operating leases, primarily for office and other facilities, and certain office equipment.
	Future minimum lease payments under noncancelable operating leases that have initial or remaining lease terms in excess of one year at March 31, 2014 are as follows:
	Years ending March 31	Yen
		(millions)
	2015	¥	18,862
	2016		14,466
	2017		13,101
	2018		8,423
	2019		7,604
	After five years		39,724
	Total minimum lease payments	¥	102,180
	Rental expenses under operating leases were ¥34,079 million, ¥32,728 million and ¥34,953 million, for the years ended March 31, 2012, 2013 and 2014, respectively.

Valuation_and_Qualifying_Accou

Valuation and Qualifying Accounts	12 Months Ended
	Mar. 31, 2014
Valuation and Qualifying Accounts	'
	(20) Valuation and Qualifying Accounts
	The valuation and qualifying accounts for the years ended March 31, 2012, 2013 and 2014 are set forth in the following table:
			Yen (millions)
					Additions
			Balance at		Charged to		Charged		Deductions*		Foreign			Balance at
			beginning		costs and		to other				currency			end of
			of year		expenses		accounts				translation			year
	March 31, 2012:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,904	¥	3,773		—	¥	3,858	¥	(526	)	¥	7,293
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	24,890	¥	11,625		—	¥	15,484	¥	(415	)	¥	20,616
	Allowance for losses on lease residual values			7,225		1,407		—		2,954		(312	)		5,366
			¥	32,115	¥	13,032		—	¥	18,438	¥	(727	)	¥	25,982
	Other assets
	Allowance for doubtful accounts		¥	23,275	¥	1,293		—	¥	1,311	¥	(221	)	¥	23,036
	Deferred tax assets
	Valuation allowance		¥	65,479	¥	18,665		—	¥	4,651	¥	(10,401	)	¥	69,092
	March 31, 2013:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,293	¥	2,810		—	¥	2,721	¥	503		¥	7,885
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	20,616	¥	9,234		—	¥	13,198	¥	1,176		¥	17,828
	Allowance for losses on lease residual values			5,366		825		—		3,178		341			3,354
			¥	25,982	¥	10,059		—	¥	16,376	¥	1,517		¥	21,182
	Other assets
	Allowance for doubtful accounts		¥	23,036	¥	687		—	¥	1,063	¥	94		¥	22,754
	Deferred tax assets
	Valuation allowance		¥	69,092	¥	9,570	¥	1,171	¥	7,347	¥	8,521		¥	81,007
	March 31, 2014:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,885	¥	3,290		—	¥	2,094	¥	596		¥	9,677
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	17,828	¥	18,503		—	¥	16,136	¥	1,364		¥	21,559
	Allowance for losses on lease residual values			3,354		401		—		1,671		47			2,131
			¥	21,182	¥	18,904		—	¥	17,807	¥	1,411		¥	23,690
	Other assets
	Allowance for doubtful accounts		¥	22,754	¥	175		—	¥	881	¥	52		¥	22,100
	Deferred tax assets
	Valuation allowance		¥	81,007	¥	16,488		—	¥	6,710	¥	6,353		¥	97,138
	*	Receivable: Bad debts written off
	Deferred tax assets:		Reversal of valuation allowance. Deductions in valuation allowance for the years ended March 31, 2012 and 2014 include a portion credited to other comprehensive income of ¥1,650 million and ¥1,173 million, respectively. Deductions in valuation allowance in the three-year period ended March 31, 2014 related to deferred tax assets that expired unused are immaterial.

Segment_Information

Segment Information	12 Months Ended
	Mar. 31, 2014
Segment Information	'
	(21) Segment Information
	Honda has four reportable segments: Motorcycle business, Automobile business, Financial services business and Power product and other businesses, which are based on Honda’s organizational structure and characteristics of products and services. Operating segments are defined as components of Honda’s about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The accounting policies used for these reportable segments are consistent with the accounting policies used in Honda’s consolidated financial statements.
	Principal products and services, and functions of each segment are as follows:
	Segment		Principal products and services		Functions
	Motorcycle Business		Motorcycles, all-terrain vehicles (ATVs) and relevant parts		Research & Development
					Manufacturing
					Sales and related services
	Automobile Business		Automobiles and relevant parts		Research & Development
					Manufacturing
					Sales and related services
	Financial Services Business		Financial, insurance services		Retail loan and lease related to
					Honda products
					Others
	Power Product and Other Businesses		Power products and relevant parts, and others		Research & Development
					Manufacturing
					Sales and related services
					Others
	Segment Information
	As of and for the year ended March 31, 2012
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
	External customers		¥	1,348,828		¥	5,805,975		¥	516,148		¥	277,144		¥	7,948,095	¥	—		¥	7,948,095
	Intersegment			—			16,767			10,428			12,590			39,785		(39,785	)		—
	Total		¥	1,348,828		¥	5,822,742		¥	526,576		¥	289,734		¥	7,987,880	¥	(39,785	)	¥	7,948,095
	Cost of sales, SG&A and R&D expenses			1,206,226			5,899,948			356,570			293,772			7,756,516		(39,785	)		7,716,731
	Segment income (loss)		¥	142,602		¥	(77,206	)	¥	170,006		¥	(4,038	)	¥	231,364	¥	—		¥	231,364
	Equity in income of affiliates		¥	31,185		¥	68,521		¥	—		¥	700		¥	100,406	¥	—		¥	100,406
	Segment assets		¥	1,006,684		¥	4,955,791		¥	5,644,380		¥	305,235		¥	11,912,090	¥	(124,491	)	¥	11,787,599
	Investments in affiliates		¥	70,275		¥	343,429		¥	—		¥	17,079		¥	430,783	¥	—		¥	430,783
	Depreciation and amortization		¥	43,564		¥	289,845		¥	211,325		¥	10,133		¥	554,867	¥	—		¥	554,867
	Capital expenditures		¥	62,075		¥	349,605		¥	686,495		¥	10,005		¥	1,108,180	¥	—		¥	1,108,180
	Damaged and impairment losses on long-lived assets		¥	—		¥	8,260		¥	1,514		¥	2,330		¥	12,104	¥	—		¥	12,104
	Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	13,032		¥	—		¥	13,032	¥	—		¥	13,032
	As of and for the year ended March 31, 2013
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
	External customers		¥	1,339,549		¥	7,709,216		¥	548,506		¥	280,676		¥	9,877,947	¥	—		¥	9,877,947
	Intersegment			—			14,374			11,750			10,994			37,118		(37,118	)		—
	Total		¥	1,339,549		¥	7,723,590		¥	560,256		¥	291,670		¥	9,915,065	¥	(37,118	)	¥	9,877,947
	Cost of sales, SG&A and R&D expenses			1,229,316			7,437,599			402,098			301,242			9,370,255		(37,118	)		9,333,137
	Segment income (loss)		¥	110,233		¥	285,991		¥	158,158		¥	(9,572	)	¥	544,810	¥	—		¥	544,810
	Equity in income of affiliates		¥	25,606		¥	56,361		¥	—		¥	756		¥	82,723	¥	—		¥	82,723
	Segment assets		¥	1,095,357		¥	5,759,126		¥	6,765,322		¥	309,149		¥	13,928,954	¥	(293,597	)	¥	13,635,357
	Investments in affiliates		¥	85,039		¥	352,317		¥	—		¥	20,020		¥	457,376	¥	—		¥	457,376
	Depreciation and amortization		¥	34,665		¥	290,522		¥	256,166		¥	9,116		¥	590,469	¥	—		¥	590,469
	Capital expenditures		¥	73,513		¥	540,625		¥	794,869		¥	14,519		¥	1,423,526	¥	—		¥	1,423,526
	Damaged and impairment losses on long-lived assets		¥	—		¥	—		¥	4,773		¥	—		¥	4,773	¥	—		¥	4,773
	Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	10,059		¥	—		¥	10,059	¥	—		¥	10,059
	As of and for the year ended March 31, 2014
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
External customers		¥	1,663,631		¥	9,176,360		¥	698,185		¥	304,275		¥	11,842,451	¥	—		¥	11,842,451
Intersegment			—			18,569			10,403			13,900			42,872		(42,872	)		—
Total		¥	1,663,631		¥	9,194,929		¥	708,588		¥	318,175		¥	11,885,323	¥	(42,872	)	¥	11,842,451
Cost of sales, SG&A and R&D expenses			1,498,026			8,791,228			525,832			319,956			11,135,042		(42,872	)		11,092,170
Segment income (loss)		¥	165,605		¥	403,701		¥	182,756		¥	(1,781	)	¥	750,281	¥	—		¥	750,281
Equity in income of affiliates		¥	36,479		¥	94,506		¥	—		¥	1,486		¥	132,471	¥	—		¥	132,471
Segment assets		¥	1,264,903		¥	6,398,580		¥	7,980,989		¥	346,177		¥	15,990,649	¥	(368,618	)	¥	15,622,031
Investments in affiliates		¥	102,359		¥	439,556		¥	—		¥	20,749		¥	562,664	¥	—		¥	562,664
Depreciation and amortization		¥	46,038		¥	383,325		¥	354,704		¥	10,653		¥	794,720	¥	—		¥	794,720
Capital expenditures		¥	57,702		¥	705,696		¥	1,131,761		¥	14,708		¥	1,909,867	¥	—		¥	1,909,867
Damaged and impairment losses on long-lived assets		¥	—		¥	—		¥	3,301		¥	—		¥	3,301	¥	—		¥	3,301
Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	18,904		¥	—		¥	18,904	¥	—		¥	18,904
Explanatory notes:
1	Segment income (loss) of each segment is measured in a consistent manner with consolidated operating income, which is income before income taxes and equity in income of affiliates before other income (expenses). Expenses not directly associated with specific segments are allocated based on the most reasonable measures applicable.
2	Segment assets of each segment are defined as total assets, including derivative financial instruments, investments in affiliates, and deferred tax assets. Segment assets are based on those directly associated with each segment and those not directly associated with specific segments are allocated based on the most reasonable measures applicable except for the corporate assets described below.
3	Intersegment sales and revenues are generally made at values that approximate arm’s-length prices.
4	Unallocated corporate assets, included in reconciling items, amounted to ¥399,732 million as of March 31, 2012, ¥293,583 million as of March 31, 2013 and ¥294,819 million as of March 31, 2014, respectively, which consist primarily of cash and cash equivalents, available-for-sale securities and held-to-maturity securities held by the Company. Reconciling items also include elimination of intersegment transactions.
5	Depreciation and amortization of Financial services business include ¥209,762 million for the year ended March 31, 2012, ¥254,933 million for the year ended March 31, 2013 and ¥352,402 million for the year ended March 31, 2014, respectively, of depreciation of property on operating leases.
6	Capital expenditures of Financial services business includes ¥683,767 million for the year ended March 31, 2012, ¥793,118 million for the year ended March 31, 2013 and ¥1,127,840 million for the year ended March 31, 2014, respectively, of purchases of operating lease assets.
7	Liabilities accrued for warranties issued are ¥60,004 million, ¥97,108 million and ¥153,898 million, for the years ended March 31, 2012, 2013 and 2014, respectively. These are mainly included in Cost of sales, SG&A and R&D expenses of Automobile business.
8	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. Effective April 1, 2012, Honda changed to the straight line method of depreciation. As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥6,358 million in Motorcycle business, ¥48,568 million in Automobile business, ¥77 million in Financial services business and ¥1,297 million in Power product and other businesses, respectively. It resulted in an increase of segment income, see note 1(k).
9	For the year ended March 31, 2012 and 2013, impacts of the floods in Thailand are mainly included in Cost of sales, SG&A and R&D expenses of Automobile business, see note 1(u).
External Sales and Other Operating Revenue by Product or Service Groups
		Yen (millions)
		2012			2013			2014
Motorcycles and relevant parts		¥	1,286,319		¥	1,274,890		¥	1,582,901
All-terrain vehicles (ATVs) and relevant parts			62,509			64,659			80,730
Automobiles and relevant parts			5,805,975			7,709,216			9,176,360
Financial, insurance services			516,148			548,506			698,185
Power products and relevant parts			208,661			221,321			251,630
Others			68,483			59,355			52,645
Total		¥	7,948,095		¥	9,877,947		¥	11,842,451
Geographical Information
As of and for the year ended March 31, 2012
		Yen (millions)
		Japan			United			Other			Total
					States			Countries
Net sales and other operating revenue		¥	1,774,573		¥	3,099,810		¥	3,073,712		¥	7,948,095
Long-lived assets		¥	1,048,402		¥	1,889,567		¥	596,939		¥	3,534,908
As of and for the year ended March 31, 2013
		Yen (millions)
		Japan			United			Other			Total
					States			Countries
Net sales and other operating revenue		¥	1,925,333		¥	4,063,727		¥	3,888,887		¥	9,877,947
Long-lived assets		¥	1,167,236		¥	2,380,885		¥	802,697		¥	4,350,818
As of and for the year ended March 31, 2014
		Yen (millions)
		Japan			United			Other			Total
					States			Countries
Net sales and other operating revenue		¥	2,216,735		¥	4,934,018		¥	4,691,698		¥	11,842,451
Long-lived assets		¥	1,280,071		¥	2,783,977		¥	1,134,021		¥	5,198,069
The above information is based on the location of the Company and its subsidiaries.
Supplemental Geographical Information
In addition to the disclosure required by U.S.GAAP, Honda provides the following supplemental information in order to provide financial statements users with additional useful information:
Supplemental geographical information based on the location of the Company and its subsidiaries
As of and for the year ended March 31, 2012
		Yen (millions)
		Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
					America									Regions					Items
Net sales and other operating revenue:
External customers		¥	1,774,573		¥	3,500,245		¥	519,329		¥	1,276,621		¥	877,327	¥	7,948,095		¥	—		¥	7,948,095
Transfers between geographic areas			1,588,379			214,511			61,463			213,857			15,805		2,094,015			(2,094,015	)		—
Total		¥	3,362,952		¥	3,714,756		¥	580,792		¥	1,490,478		¥	893,132	¥	10,042,110		¥	(2,094,015	)	¥	7,948,095
Cost of sales, SG&A and R&D expenses		¥	3,472,786		¥	3,491,463		¥	592,901		¥	1,413,608		¥	836,176	¥	9,806,934		¥	(2,090,203	)	¥	7,716,731
Operating income (loss)		¥	(109,834	)	¥	223,293		¥	(12,109	)	¥	76,870		¥	56,956	¥	235,176		¥	(3,812	)	¥	231,364
Assets		¥	3,112,901		¥	6,333,851		¥	568,790		¥	1,070,331		¥	611,818	¥	11,697,691		¥	89,908		¥	11,787,599
Long-lived assets		¥	1,048,402		¥	1,970,631		¥	111,354		¥	274,182		¥	130,339	¥	3,534,908		¥	—		¥	3,534,908
As of and for the year ended March 31, 2013
		Yen (millions)
		Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
					America									Regions					Items
Net sales and other operating revenue:
External customers		¥	1,925,333		¥	4,612,361		¥	536,856		¥	1,926,434		¥	876,963	¥	9,877,947		¥	—		¥	9,877,947
Transfers between geographic areas			1,968,179			244,741			105,254			379,213			19,504		2,716,891			(2,716,891	)		—
Total		¥	3,893,512		¥	4,857,102		¥	642,110		¥	2,305,647		¥	896,467	¥	12,594,838		¥	(2,716,891	)	¥	9,877,947
Cost of sales, SG&A and R&D expenses		¥	3,715,084		¥	4,648,184		¥	641,650		¥	2,158,889		¥	860,773	¥	12,024,580		¥	(2,691,443	)	¥	9,333,137
Operating income (loss)		¥	178,428		¥	208,918		¥	460		¥	146,758		¥	35,694	¥	570,258		¥	(25,448	)	¥	544,810
Assets		¥	3,264,383		¥	7,645,540		¥	673,667		¥	1,523,192		¥	660,856	¥	13,767,638		¥	(132,281	)	¥	13,635,357
Long-lived assets		¥	1,167,236		¥	2,481,097		¥	124,088		¥	434,827		¥	143,570	¥	4,350,818		¥	—		¥	4,350,818
As of and for the year ended March 31, 2014
		Yen (millions)
		Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
					America									Regions					Items
Net sales and other operating revenue:
External customers		¥	2,216,735		¥	5,595,981		¥	676,502		¥	2,340,100		¥	1,013,133	¥	11,842,451		¥	—		¥	11,842,451
Transfers between geographic areas			1,975,544			374,018			98,766			486,823			12,368		2,947,519			(2,947,519	)		—
Total		¥	4,192,279		¥	5,969,999		¥	775,268		¥	2,826,923		¥	1,025,501	¥	14,789,970		¥	(2,947,519	)	¥	11,842,451
Cost of sales, SG&A and R&D expenses		¥	3,978,185		¥	5,679,094		¥	792,393		¥	2,609,023		¥	980,600	¥	14,039,295		¥	(2,947,125	)	¥	11,092,170
Operating income (loss)		¥	214,094		¥	290,905		¥	(17,125	)	¥	217,900		¥	44,901	¥	750,675		¥	(394	)	¥	750,281
Assets		¥	3,442,746		¥	8,825,278		¥	709,469		¥	1,996,929		¥	767,225	¥	15,741,647		¥	(119,616	)	¥	15,622,031
Long-lived assets		¥	1,280,071		¥	3,025,095		¥	133,061		¥	588,413		¥	171,429	¥	5,198,069		¥	—		¥	5,198,069
Explanatory notes:
1	Major countries or regions in each geographic area:
North America		United States, Canada, Mexico
Europe		United Kingdom, Germany, France, Belgium, Russia
Asia		Thailand, Indonesia, China, India, Vietnam
Other Regions		Brazil, Australia
2	Operating income (loss) of each geographical region is measured in a consistent manner with consolidated operating income, which is income before income taxes and equity in income of affiliates before other income (expenses).
3	Assets of each geographical region are defined as total assets, including derivative financial instruments, investments in affiliates, and deferred tax assets.
4	Sales and revenues between geographic areas are generally made at values that approximate arm’s-length prices.
5	Unallocated corporate assets, included in reconciling items, amounted to ¥399,732 million as of March 31, 2012, ¥293,583 million as of March 31, 2013 and ¥294,819 million as of March 31, 2014, respectively, which consist primarily of cash and cash equivalents, available-for-sale securities and held-to-maturity securities held by the Company. Reconciling items also include elimination of transactions between geographic areas.
6	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. Effective April 1, 2012, Honda changed to the straight line method of depreciation. As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥42,486 million in Japan, ¥9,602 million in North America, ¥1,068 million in Europe and ¥3,144 million in Asia, respectively. It resulted in an increase of operating income, see note 1(k).
7	For the year ended March 31, 2012 and 2013, impacts of the floods in Thailand are included in Cost of sales, SG&A and R&D expenses of Asia, see note 1(u).

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Mar. 31, 2014
Selected Quarterly Financial Data (Unaudited) *	'
	(22) Selected Quarterly Financial Data (Unaudited)*
	Quarterly financial data for the years ended March 31, 2012, 2013 and 2014 are set forth in the following table:
			Yen (millions)						Yen
			Net sales and other		Operating		Net income (loss)		Basic net income (loss)
			operating revenue		Income (loss)		attributable to		attributable to
							Honda Motor Co., Ltd.		Honda Motor Co., Ltd.
									per common share
	Year ended March 31, 2012:
	First quarter		¥	1,714,596	¥	22,579	¥	31,797	¥	17.64
	Second quarter			1,885,892		52,511		60,429		33.53
	Third quarter			1,942,545		44,298		47,662		26.45
	Fourth quarter			2,405,062		111,976		71,594		39.72
			¥	7,948,095	¥	231,364	¥	211,482	¥	117.34
	Year ended March 31, 2013:
	First quarter		¥	2,435,909	¥	176,013	¥	131,723	¥	73.09
	Second quarter			2,271,286		100,867		82,233		45.63
	Third quarter			2,425,792		131,941		77,441		42.97
	Fourth quarter			2,744,960		135,989		75,752		42.03
			¥	9,877,947	¥	544,810	¥	367,149	¥	203.71
	Year ended March 31, 2014:
	First quarter		¥	2,834,095	¥	184,963	¥	122,499	¥	67.97
	Second quarter			2,890,221		171,451		120,368		66.79
	Third quarter			3,020,889		228,574		160,732		89.18
	Fourth quarter			3,097,246		165,293		170,508		94.61
			¥	11,842,451	¥	750,281	¥	574,107	¥	318.54
	*	All quarterly financial data is unaudited and also has not been reviewed by the independent registered public accounting firm.

General_and_Summary_of_Signifi1

General and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Mar. 31, 2014
Description of Business	'
	(a) Description of Business
	Honda Motor Co., Ltd. (the “Company”) and its subsidiaries (collectively “Honda”) mainly develop, manufacture and distribute motorcycles, automobiles, power products, and also provide financing for the sale of those products. Principal manufacturing facilities are located in Japan, the United States of America, Canada, Mexico, the United Kingdom, Italy, China, India, Thailand, Vietnam, Indonesia, Argentina, Brazil and Turkey.
Basis of Presenting Consolidated Financial Statements	'
	(b) Basis of Presenting Consolidated Financial Statements
	The Company and its Japanese subsidiaries maintain their books of account in conformity with financial accounting standards of Japan, and its foreign subsidiaries generally maintain their books of account in conformity with those of the countries of their domicile.
	The consolidated financial statements presented herein have been prepared in a manner and reflect the adjustments which are necessary to conform them with U.S. generally accepted accounting principles (U.S.GAAP).
Consolidation Policy	'
	(c) Consolidation Policy
	The consolidated financial statements include the accounts of the Company, its subsidiaries and those variable interest entities where Honda is the primary beneficiary. All significant intercompany balances and transactions have been eliminated in consolidation.
	Noncontrolling interests in the net assets of subsidiary are reported as a component of equity in the consolidated financial statements. Changes in a parent’s ownership interest while the parent retains its controlling financial interest in its subsidiary are accounted for as equity transactions. Noncontrolling interests in a subsidiary’s earnings or losses are reported as a component of net income in the consolidated financial statements.
	Investments in affiliates in which Honda has the ability to exercise significant influence over their operating and financial policies, but where Honda does not have a controlling financial interest are accounted for using the equity method.
	There are some subsidiaries and affiliates of which the fiscal year-end is December 31.
	Effective April 1, 2013, a subsidiary of the Company changed its fiscal year-end from December 31 to March 31. As a result, the Company eliminated the previously existing three month differences between the reporting periods of the Company and the subsidiary in the consolidated financial statements. The elimination of the lag period represents a change in accounting principle and has been reported by retrospective application. The impacts on the retained earnings and noncontrolling interests as of April 1, 2011 are ¥6,023 million and ¥1,658 million, respectively. Honda believes the effect of the retrospective application is not material to the Company’s consolidated financial statements as of and for the year ended March 31, 2012 and 2013, and therefore the Company’s consolidated financial statements have not been retrospectively adjusted, except for the adjustment to retained earnings and noncontrolling interests as of April 1, 2011.
Use of Estimates	'
	(d) Use of Estimates
	Management of Honda has made a number of estimates and assumptions relating to the reporting of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities to prepare its consolidated financial statements in conformity with U.S. GAAP. Significant items subject to such estimates and assumptions include, but are not limited to, allowance for credit losses, losses on lease residual values, realizable values of inventories, realization of deferred tax assets, damaged and impairment losses on long-lived assets, unrecognized tax benefits, product warranty obligations, the fair values of assets and obligations related to employee benefits, and the fair value of derivative financial instruments. Further changes in the economic environment surrounding Honda, effects by market conditions, effects of currency fluctuations or other factors have combined to increase the uncertainty inherent in such estimates and assumptions. Actual results could differ from those estimates.
Revenue Recognition	'
	(e) Revenue Recognition
	Sales of manufactured products are recognized when persuasive evidence of an arrangement exists, delivery has occurred, title and risk of loss have passed to the customers, the sales price is fixed or determinable, and collectibility is probable.
	Honda provides dealer incentives passed on to the end customers generally in the form of below-market interest rate loans or lease programs. The amount of interest or lease subsidies paid is the difference between the amount offered to retail customers and the amount stemmed from a market-based interest or lease rate. Honda also provides dealer incentives retained by the dealer, which generally represent discounts provided from Honda to the dealers. These incentives are classified as a reduction of sales revenue as the consideration is paid in cash, because Honda does not receive an identifiable benefit in exchange for this consideration. The incentives are estimated and accrued at the time the product is sold to the dealer.
	Operating lease revenues are recorded on a straight-line basis over the term of the lease.
	Interest income from finance receivables is recognized using the interest method. Finance receivable origination fees and certain direct origination costs are deferred, and the net fee or cost is amortized using the interest method over the contractual life of the finance receivables.
	Taxes collected from customers and remitted to governmental authorities on revenue-producing transactions are accounted for on a net basis and therefore are excluded from revenues in the consolidated statements of income.
Cash Equivalents	'
	(f) Cash Equivalents
	Honda considers all highly liquid debt instruments with original maturities of three months or less to be cash equivalents. Cash equivalents mainly consist of money market funds and certificates of deposit.
Inventories	'
	(g) Inventories
	Inventories are stated at the lower of cost or market. Cost is determined principally on a first-in, first-out basis.
Investments in Securities	'
	(h) Investments in Securities
	Investments in securities consist of investment in affiliates and debt and equity securities.
	Investments in affiliates in which Honda has the ability to exercise significant influence over their operating and financial policies, but where Honda does not have a controlling financial interest are accounted for using the equity method. Differences between the cost of investments in affiliates and the amount of underlying equity of the affiliates principally represent investor level goodwill.
	Honda considers whether the fair value of any of its equity method investments have declined below their carrying value whenever adverse events or changes in circumstances indicate that recorded values may not be recoverable. If Honda considers any such decline to be other-than-temporary based on various factors, then a write-down will be recorded to estimated fair value.
	Honda classifies its debt and marketable equity securities into the following categories: available-for-sale, trading, or held-to-maturity. Debt securities classified as “held-to-maturity” securities are reported at amortized cost. Debt and marketable equity securities classified as “trading” securities are reported at fair value, with unrealized gains and losses included in earnings. Other debt and marketable equity securities are classified as “available-for-sale” securities and are reported at fair value, with unrealized gains or losses, net of deferred taxes included in accumulated other comprehensive income (loss) in the equity section of the consolidated balance sheets. The costs of available-for-sale securities sold are accounted for using the moving-average method. Honda did not hold any “trading” securities at March 31, 2013 and 2014.
	Honda periodically compares the fair value of debt and marketable equity securities with their cost basis. If the fair value of the securities has declined below the cost basis and such decline is judged to be other-than-temporary, Honda recognizes the impairment of the securities through a charge to income. The determination of other-than-temporary impairment is based upon an assessment of the facts and circumstances related to each investment security. In assessing impairment of securities, Honda considers the factors such as degree and period of the decline in fair value, financial position and results of operations of investees and forecast earnings based on market and economic trend in which the investees operate. Honda did not recognize significant impairment loss on investments in securities for the years ended March 31, 2012, 2013 and 2014.
	Non-marketable equity securities are carried at cost, and are examined for the possibility of impairment periodically.
Goodwill	'
	(i) Goodwill
	Goodwill, all of which is allocated to Honda’s reporting units, is not amortized but is tested for impairment at least annually. Honda performs its annual impairment review of goodwill at March 31, and when a triggering event occurs between annual impairment dates. For the years ended March 31, 2012, 2013 and 2014, Honda did not recognize any goodwill impairment losses.
	The carrying amount of goodwill at March 31, 2013 and 2014 was ¥10,296 million and ¥11,439 million, respectively and is included in other assets of the consolidated balance sheets.
Property on Operating Leases	'
	(j) Property on Operating Leases
	Property on operating leases is reported at cost, less accumulated depreciation. Depreciation of vehicles is generally provided on a straight-line basis to an estimated residual value over the lease term. The residual values of the vehicles related to operating leases are estimated by using the estimate of future used vehicle values, taking into consideration external industry data and our own historical experience.
Depreciation and Amortization	'
	(k) Depreciation and Amortization
	Depreciation of property, plant and equipment is calculated principally by the straight line method based on estimated useful lives and salvage values of the respective assets.
	The estimated useful lives used in computing depreciation and amortization of property, plant and equipment are as follows:
	Asset	Life
	Buildings and structures		3 to 50 years
	Machinery and equipment		2 to 20 years
	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. In recent years, because sales of global strategic product models are increasing, Honda has been enhancing its production systems and the versatility of production equipment to have better flexibility to meet changes in global customer demand. Further, Honda has resumed more normalized capital expenditures which Honda had previously held down due to the financial crisis beginning in the fiscal year ended March 31, 2009. Effective April 1, 2012, Honda changed to the straight line method of depreciation because management believes it better reflects the future economic benefit from the usage of property, plant and equipment under this more flexible and versatile production arrangement. The effect of the change in depreciation method is recognized prospectively as a change in accounting estimate in accordance with the FASB Accounting Standards Codification (ASC) 250 “Accounting Changes and Error Corrections”.
	As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥56,300 million. Net income attributable to Honda Motor Co., Ltd. and Basic net income attributable to Honda Motor Co., Ltd. per common share for the year ended March 31, 2013 increased by approximately ¥35,746 million and ¥19.83, respectively.
Impairment of Long-Lived Assets to Be Held and Used and Long-Lived Assets to Be Disposed of	'
	(l) Impairment of Long-Lived Assets to Be Held and Used and Long-Lived Assets to Be Disposed of
	Honda’s long-lived assets and identifiable intangible assets other than goodwill having finite useful lives are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of an asset to be held and used is measured by a comparison of the carrying amount of an asset to future net cash flows (undiscounted and without interest charges) expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets. Honda did not recognize any significant impairment losses on long-lived assets, excluding property on operating leases for the years ended March 31, 2012, 2013 and 2014.
	Assets to be disposed of by sale are reported at the lower of the carrying amount or estimated fair value less costs to sell.
Income Taxes	'
	(m) Income Taxes
	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period that includes the enactment date.
	Honda recognizes in the consolidated financial statements the impact of a tax position, if any, based on the technical merits of the position, when that position is more likely than not to be sustained upon examination. Benefits from tax positions that meet the more likely than not recognition threshold are measured at the largest amount of benefit that is greater than 50 percent likely to be realized upon settlement. Honda accounts for interest and penalties related to the liability for unrecognized tax benefits as a component of income tax expense in the consolidated statements of income.
Product-Related Expenses	'
	(n) Product-Related Expenses
	Advertising and sales promotion costs are expensed as incurred. Advertising expenses were ¥195,284 million, ¥254,016 million and ¥297,514 million, for the years ended March 31, 2012, 2013 and 2014, respectively. Estimated costs related to product warranty are accrued at the time the products are sold to customers, or those costs for new warranty programs, including product recalls, are deemed to be probable and can be reasonably estimated. Estimated warranty expenses are provided based on historical warranty claim experience with consideration given to the expected level of future warranty costs as well as current information on repair costs. Included in warranty expenses accruals are costs for general warranties on vehicles Honda sells and costs for warranty programs, including product recalls.
Basic Net Income Attributable to Honda Motor Co., Ltd. per Common Share	'
	(o) Basic Net Income Attributable to Honda Motor Co., Ltd. per Common Share
	Basic net income attributable to Honda Motor Co., Ltd. per common share has been computed by dividing net income attributable to Honda Motor Co., Ltd. by the weighted average number of common shares outstanding during each year. The weighted average number of common shares outstanding for the years ended March 31, 2012, 2013 and 2014 was 1,802,300,720 shares, 1,802,298,819 shares and 1,802,294,383 shares, respectively. There were no potentially dilutive shares outstanding during the years ended March 31, 2012, 2013 or 2014.
Foreign Currency Translation and Transactions	'
	(p) Foreign Currency Translation and Transactions
	Foreign currency financial statement amounts are translated into Japanese yen on the basis of the year-end exchange rate for all assets and liabilities and the weighted average rate for the year for all income and expense amounts. The resulting translation adjustments are included in accumulated other comprehensive income (loss) in the equity section of the consolidated balance sheets.
	All revenues and expenses associated with foreign currencies are converted at the rates of exchange prevailing when such transactions occur and foreign currency receivables and payables are re-measured at the applicable exchange rates on the balance sheet date. Foreign currency translation and transaction gains or losses are included in other income (expenses)-other, net and these net gains or losses for each of the years in the three-year period ended March 31, 2014 are as follows:
	Yen (millions)
	2012	2013		2014
	¥  4,563	¥  36,794		¥  (6,461)
	The gains or losses on translation of receivables and payables dominated in foreign currencies intended to be hedged are presented on a net basis with derivative financial instruments (note 17).
Derivative Financial Instruments	'
	(q) Derivative Financial Instruments
	Honda has entered into foreign exchange agreements and interest rate agreements to manage currency and interest rate exposures. These instruments include foreign currency forward contracts, currency swap agreements, currency option contracts and interest rate swap agreements (notes 16 and 17).
	Honda recognizes all derivative financial instruments at fair value in its consolidated balance sheets. Derivative asset and liability positions are presented net by counterparty on the consolidated balance sheets when valid master netting agreements exist and the other conditions set out in the FASB Accounting Standards Codification (ASC) 210-20 “Balance Sheet-Offsetting” are met.
	The Company applies hedge accounting for certain foreign currency forward contracts related to forecasted foreign currency transactions between the Company and its subsidiaries. These are designated as cash flow hedges on the date derivative contracts are entered into. The Company has a documented currency rate risk management policy. In addition, it documents all relationships between derivative financial instruments designated as cash flow hedges and the relevant hedged items to identify the relationship between them. The Company assesses, both at the hedge’s inception and on an ongoing basis, whether the derivative financial instruments designated as cash flow hedge are highly effective to offset changes in cash flows of hedged items.
	When it is determined that a derivative financial instrument is not highly effective as a cash flow hedge, when the hedged item matures, is sold or is terminated, or when it is identified that the forecasted transaction is no longer probable, the Company discontinues hedge accounting. To the extent derivative financial instruments are designated as cash flow hedges and have been assessed as being highly effective, changes in their fair value are recognized in other comprehensive income (loss). The amounts are reclassified into earnings in the period when forecasted hedged transactions affect earnings. When these cash flow hedges prove to be ineffective, changes in the fair value of the derivatives are immediately recognized in earnings.
	Changes in the fair value of derivative financial instruments not designated as accounting hedges are recognized in earnings in the period of the change.
	Honda does not hold any derivative financial instruments for trading purposes.
Shipping and Handling Costs	'
	(r) Shipping and Handling Costs
	Shipping and handling costs included in selling, general and administrative expenses for each of the years in the three-year period ended March 31, 2014 are as follows:
	Yen (millions)
	2012	2013		2014
	¥ 155,276	¥160,843		¥180,554
Asset Retirement Liability	'
	(s) Asset Retirement Liability
	Honda recognizes an asset retirement liability if the fair value of the obligation can be reasonably estimated. Asset retirement obligations include those for which an entity has a legal obligation to perform an asset retirement activity, however, the timing and (or) method of settling the obligation are conditional on a future event that may or may not be within the control of the entity.
Adoption of New Accounting Pronouncements	'
	(t) Adoption of New Accounting Pronouncements
	In February 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2013-02 “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income”. This amendment requires reporting entities to provide information about the amounts reclassified out of accumulated other comprehensive income by component, and to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income.
	Honda adopted ASU 2013-02, effective April 1, 2013, and discloses in accompanying note 15 to consolidated financial statements. This adoption has no impact on the Honda’s financial position or results of operations.
New Accounting Pronouncements Not Yet Adopted	'
	(v) New Accounting Pronouncements Not Yet Adopted
	In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09 “Revenue from Contracts with Customers”, which amends the revenue recognition requirements in the FASB Accounting Standards Codification (ASC). This statement requires that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The statement shall be applied using one of two methods: retrospectively to each prior reporting period presented, or retrospectively with the cumulative effect of initially applying this statement recognized at the date of initial application. The Company has not yet determined which method it will apply. This statement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. Honda is currently evaluating the impact of this statement on the Company’s consolidated financial position or results of operations.
The Floods in Thailand	'
Impact on the Company's Consolidated Financial Position or Results of Operations	'
	(u) Impact on the Company’s Consolidated Financial Position or Results of Operations of the Floods in Thailand
	In October 2011, Thailand suffered from severe floods that caused damage to inventories, and machinery and equipment of certain consolidated subsidiaries and affiliates of the Company. Accordingly, production activities in plant facilities at Honda and its affiliates had been temporarily affected by the floods for the year ended March 31, 2012.
	Honda recognized ¥23,420 million of costs and expenses, of which ¥10,680 million is included in cost of sales and ¥12,740 million is included in selling, general and administrative expenses in the accompanying consolidated statements of income for the year ended March 31, 2012. These costs and expenses mainly consist of losses on damaged inventories of ¥7,330 million which is included in cost of sales, and losses on damaged property, plant and equipment of ¥7,654 million which is included in selling, general and administrative expenses.
	In addition, Honda recognized insurance recoveries of ¥21,725 million and ¥16,278 million for the years ended March 31, 2012 and 2013, respectively, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income. Honda recognizes insurance recoveries in excess of the incurred losses when settlements with insurance companies are reached.

General_and_Summary_of_Signifi2

General and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Mar. 31, 2014
Estimated Useful Lives Used in Computing Depreciation and Amortization of Property, Plant and Equipment	'
	The estimated useful lives used in computing depreciation and amortization of property, plant and equipment are as follows:
	Asset	Life
	Buildings and structures		3 to 50 years
	Machinery and equipment		2 to 20 years
Foreign Currency Translation and Transaction Net Gains or Losses	'
	Foreign currency translation and transaction gains or losses are included in other income (expenses)-other, net and these net gains or losses for each of the years in the three-year period ended March 31, 2014 are as follows:
	Yen (millions)
	2012	2013		2014
	¥  4,563	¥  36,794		¥  (6,461)
Shipping and Handling Costs	'
	Shipping and handling costs included in selling, general and administrative expenses for each of the years in the three-year period ended March 31, 2014 are as follows:
	Yen (millions)
	2012	2013		2014
	¥ 155,276	¥160,843		¥180,554

Finance_Income_and_Related_Cos1

Finance Income and Related Costs of Finance Subsidiaries (Tables)	12 Months Ended
	Mar. 31, 2014
Finance Income and Related Costs of Finance Subsidiaries	'
	Net sales and other operating revenue and cost of sales include finance income and related costs of finance subsidiaries for each of the years in the three-year period ended March 31, 2014 as follows:
		Yen (millions)
		2012		2013		2014
	Finance income	¥	526,576	¥	560,256	¥	708,588
	Finance costs		293,216		336,203		440,148

Finance_Receivables_Tables

Finance Receivables (Tables)	12 Months Ended
	Mar. 31, 2014
Finance Subsidiaries-receivables, Net	'
	Finance subsidiaries-receivables, net, consisted of the following at March 31, 2013 and 2014:
			Yen (millions)
			2013			2014
	Retail		¥	3,865,430		¥	4,678,741
	Direct financing lease			448,672			422,936
	Wholesale flooring			389,562			434,219
	Commercial loans			42,433			63,176
	Total finance receivables			4,746,097			5,599,072
	Less:
	Allowance for credit losses			19,716			24,851
	Allowance for losses on lease residual values			3,354			2,131
	Unearned interest income and fees			18,697			38,093
				4,704,330			5,533,997
	Less:
	Finance receivables included in trade accounts and notes receivables, net			461,450			498,230
	Finance receivables included in other assets, net			211,743			253,999
	Finance subsidiaries-receivables, net			4,031,137			4,781,768
	Less current portion			1,243,002			1,464,215
	Noncurrent finance subsidiaries-receivables, net		¥	2,788,135		¥	3,317,553
Changes in Allowance for Credit Losses on Finance Receivables	'
	The following tables present the changes in the allowance for credit losses on finance receivables for the years ended March 31, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2013		Retail			Direct			Wholesale			Total
						financing lease
	Balance at beginning of year		¥	20,497		¥	1,151		¥	1,401		¥	23,049
	Provision			8,707			392			59			9,158
	Charge-offs			(20,838	)		(940	)		(289	)		(22,067	)
	Recoveries			8,143			117			16			8,276
	Adjustments from foreign currency translation			1,134			69			97			1,300
	Balance at end of year		¥	17,643		¥	789		¥	1,284		¥	19,716
			Yen (millions)
	For the year ended March 31, 2014		Retail			Direct			Wholesale			Total
						financing lease
	Balance at beginning of year		¥	17,643		¥	789		¥	1,284		¥	19,716
	Provision			18,616			310			1,484			20,410
	Charge-offs			(27,550	)		(573	)		(425	)		(28,548	)
	Recoveries			11,676			93			11			11,780
	Adjustments from foreign currency translation			1,252			17			224			1,493
	Balance at end of year		¥	21,637		¥	636		¥	2,578		¥	24,851
Age Analysis of Past Due Finance Receivables	'
	The following tables present an age analysis of past due finance receivables at March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		30-59 days			60-89 days			90 days and			Total			Current*		Total finance
			past due			past due			greater			past due					receivables
									past due
	Retail
	New auto		¥	12,947		¥	1,805		¥	2,607		¥	17,359		¥	3,247,241	¥	3,264,600
	Used & certified auto			5,064			643			276			5,983			434,183		440,166
	Others			1,213			419			1,353			2,985			157,679		160,664
	Total retail			19,224			2,867			4,236			26,327			3,839,103		3,865,430
	Direct financing lease			966			161			1,644			2,771			445,901		448,672
	Wholesale
	Wholesale flooring			205			67			311			583			388,979		389,562
	Commercial loans			—			—			—			—			42,433		42,433
	Total wholesale			205			67			311			583			431,412		431,995
	Total finance receivables		¥	20,395		¥	3,095		¥	6,191		¥	29,681		¥	4,716,416	¥	4,746,097
			Yen (millions)
	As of March 31, 2014		30-59 days			60-89 days			90 days and			Total			Current*		Total finance
			past due			past due			greater			past due					receivables
									past due
	Retail
	New auto		¥	15,948		¥	2,069		¥	2,745		¥	20,762		¥	4,044,290	¥	4,065,052
	Used & certified auto			5,557			689			281			6,527			424,872		431,399
	Others			1,239			507			1,800			3,546			178,744		182,290
	Total retail			22,744			3,265			4,826			30,835			4,647,906		4,678,741
	Direct financing lease			1,106			214			384			1,704			421,232		422,936
	Wholesale
	Wholesale flooring			526			227			758			1,511			432,708		434,219
	Commercial loans			—			—			133			133			63,043		63,176
	Total wholesale			526			227			891			1,644			495,751		497,395
	Total finance receivables		¥	24,376		¥	3,706		¥	6,101		¥	34,183		¥	5,564,889	¥	5,599,072
	*	Includes recorded investment of finance receivables that are less than 30 days past due.
Contractual Maturities of Finance Receivables	'
	The following schedule shows the contractual maturities of finance receivables for each of the five years following March 31, 2014 and thereafter:
	Years ending March 31		Yen
			(millions)
	2015		¥	1,992,551
	2016			1,425,249
	2017			1,020,626
	2018			685,494
	2019			356,586
	After five years			118,566
				3,606,521
	Total		¥	5,599,072
Consumer portfolio segment	'
Finance Receivables by Credit Quality Indicator	'
	The following tables present the balances of consumer finance receivables by this credit quality indicator at March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Performing			Nonperforming			Total consumer
									finance
									receivables
	Retail
	New auto		¥	3,260,188		¥	4,412		¥	3,264,600
	Used & certified auto			439,247			919			440,166
	Others			158,892			1,772			160,664
	Total retail			3,858,327			7,103			3,865,430
	Direct financing lease			446,867			1,805			448,672
	Total		¥	4,305,194		¥	8,908		¥	4,314,102
			Yen (millions)
	As of March 31, 2014		Performing			Nonperforming			Total consumer
									finance
									receivables
	Retail
	New auto		¥	4,060,238		¥	4,814		¥	4,065,052
	Used & certified auto			430,429			970			431,399
	Others			179,983			2,307			182,290
	Total retail			4,670,650			8,091			4,678,741
	Direct financing lease			422,338			598			422,936
	Total		¥	5,092,988		¥	8,689		¥	5,101,677
Wholesale	'
Finance Receivables by Credit Quality Indicator	'
	The following tables present the balances of wholesale receivables by this credit quality indicator at March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Group A			Group B			Total
	Wholesale
	Wholesale flooring		¥	236,203		¥	153,359		¥	389,562
	Commercial loans			24,198			18,235			42,433
	Total		¥	260,401		¥	171,594		¥	431,995
			Yen (millions)
	As of March 31, 2014		Group A			Group B			Total
	Wholesale
	Wholesale flooring		¥	245,019		¥	189,200		¥	434,219
	Commercial loans			36,364			26,812			63,176
	Total		¥	281,383		¥	216,012		¥	497,395

Variable_Interest_Entities_Tab

Variable Interest Entities (Tables)	12 Months Ended
	Mar. 31, 2014
Assets and Liabilities of Consolidated VIEs	'
	The following table presents the balances of the assets and liabilities of consolidated VIEs at March 31, 2013 and 2014.
			Yen (millions)
			2013		2014
	Finance subsidiaries-receivables, net		¥	713,631	¥	872,621
	Restricted cash*1			20,885		27,468
	Other assets			1,545		1,462
	Total assets		¥	736,061	¥	901,551
	Secured debt*2		¥	718,980	¥	877,054
	Other liabilities			237		249
	Total liabilities		¥	719,217	¥	877,303
	*1	Restricted cash as collateral for the payment of the related secured debt obligation is included in other current assets and investment and advances-other on the consolidated balance sheets.
	*2	Secured debt is included in short-term, current portion of long-term and long-term debt on the consolidated balance sheets.

Inventories_Tables

Inventories (Tables)	12 Months Ended
	Mar. 31, 2014
Inventories	'
	Inventories at March 31, 2013 and 2014 are summarized as follows:
		Yen (millions)
		2013		2014
	Finished goods	¥	726,034	¥	759,099
	Work in process		53,035		69,731
	Raw materials		436,352		474,065
	Total	¥	1,215,421	¥	1,302,895

Investments_in_and_Advances_to1

Investments in and Advances to Affiliates (Tables)	12 Months Ended
	Mar. 31, 2014
Equity Securities which Have Quoted Market Values, Included in Investments in Affiliates	'
	Investments in affiliates include equity securities which have quoted market values at March 31, 2013 and 2014 compared with related carrying amounts as follows:
		Yen (millions)
		2013				2014
	Carrying amounts	¥	175,420			¥	212,615
	Market values		220,221				242,671
Combined Financial Information in Respect of Affiliates Accounted for under Equity Method	'
	Certain combined financial information in respect of affiliates accounted for under the equity method at March 31, 2013 and 2014, and for each of the years in the three-year period ended March 31, 2014 is shown below (note 21):
		Yen (millions)
	As of March 31, 2013	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Current assets	¥	228,358			¥	1,335,075	¥	25,438	¥	1,588,871
	Other assets, principally property, plant and equipment		134,901				1,137,654		27,219		1,299,774
	Total assets		363,259				2,472,729		52,657		2,888,645
	Current liabilities		149,033				1,013,565		8,358		1,170,956
	Other liabilities		10,075				242,194		2,979		255,248
	Total liabilities		159,108				1,255,759		11,337		1,426,204
	Equity	¥	204,151			¥	1,216,970	¥	41,320	¥	1,462,441
		Yen (millions)
	As of March 31, 2014	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Current assets	¥	258,565			¥	1,732,609	¥	26,185	¥	2,017,359
	Other assets, principally property, plant and equipment		126,888				1,212,313		30,450		1,369,651
	Total assets		385,453				2,944,922		56,635		3,387,010
	Current liabilities		168,060				1,337,236		10,111		1,515,407
	Other liabilities		12,849				226,822		2,972		242,643
	Total liabilities		180,909				1,564,058		13,083		1,758,050
	Equity	¥	204,544			¥	1,380,864	¥	43,552	¥	1,628,960
		Yen (millions)
	For the year ended March 31, 2012	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	888,914			¥	3,579,019	¥	23,934	¥	4,491,867
	Net income attributable to Honda’s affiliates		72,168				177,309		1,516		250,993
		Yen (millions)
	For the year ended March 31, 2013	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	891,343			¥	3,876,766	¥	25,918	¥	4,794,027
	Net income attributable to Honda’s affiliates		60,586				162,037		1,717		224,340
		Yen (millions)
	For the year ended March 31, 2014	Motorcycle				Automobile		Power Product		Total
		Business				Business		and Other
								Businesses
	Net sales	¥	1,070,837			¥	4,314,804	¥	27,578	¥	5,413,219
	Net income attributable to Honda’s affiliates		79,381				230,397		2,708		312,486
Significant Investments in Affiliates Accounted for under Equity Method	'
	Significant investments in affiliates accounted for under the equity method at March 31, 2013 and 2014 are shown below:
	Business	Company		Percentage ownership
	Motorcycle	P.T. Astra Honda Motor			50	%
	Automobile	Guangqi Honda Automobile Co., Ltd.			50	%
		Dongfeng Honda Automobile Co., Ltd.			50	%
		Dongfeng Honda Engine Co., Ltd.			50	%
Transactions with Affiliates	'
	Trade receivables and trade payables include the following balances with affiliates at March 31, 2013 and 2014, and purchases and sales include the following transactions with affiliates for each of the years in the three-year period ended March 31, 2014. Honda mainly purchases materials, supplies and services from affiliates, and sells finished goods, parts used in its products, equipment and services to affiliates.
		Yen (millions)
		2013				2014
	Amounts due from	¥	160,470			¥	225,383
	Amounts due to		97,958				138,181
		Yen (millions)
		2012				2013		2014
	Purchases from	¥	762,415			¥	789,261	¥	1,028,523
	Sales to		561,426				636,299		786,802

Investments_and_AdvancesOther_

Investments and Advances-Other (Tables)	12 Months Ended
	Mar. 31, 2014
Investments and Advances-Other, Current	'
		Yen (millions)
		2013		2014
	Current
	Corporate debt securities	¥	1,553	¥	11,050
	Government bonds		—		2,000
	Local bonds		—		6,620
	Advances		926		1,028
	Certificates of deposit		1,550		1,558
	Other		10,846		15,012
	Total	¥	14,875	¥	37,268
Investments and Advances-Other, Noncurrent	'
		Yen (millions)
		2013		2014
	Noncurrent
	Auction rate securities	¥	6,928	¥	6,999
	Marketable equity securities		117,110		138,476
	Corporate debt securities		1,505		8,542
	Government bonds		2,000		—
	Local bonds		9,499		15,850
	U.S. government agency debt securities		1,068		5,455
	Non-marketable equity securities accounted for under the cost method
	Non-marketable preferred stocks		969		969
	Other		10,780		10,316
	Guaranty deposits		20,210		18,742
	Advances		2,132		1,998
	Other		37,479		46,314
	Total	¥	209,680	¥	253,661
Available-for-sale Securities and Held-to-maturity Securities	'
	Certain information with respect to available-for-sale securities and held-to-maturity securities at March 31, 2013 and 2014 are summarized below:
		Yen (millions)
		2013		2014
	Available-for-sale
	Cost	¥	49,990	¥	84,820
	Fair value		128,848		185,960
	Gross unrealized gains		80,453		101,917
	Gross unrealized losses		1,595		777
	Held-to-maturity
	Amortized cost	¥	16,511	¥	34,650
	Fair value		16,556		34,667
	Gross unrealized gains		45		17
	Gross unrealized losses		—		—
Maturities of Debt Securities Classified as Available-for-sale	'
	Maturities of debt securities classified as available-for-sale at March 31, 2014 are as follows:
		Yen
		(millions)
	Due within one year	¥	2,676
	Due after one year through five years		12,968
	Due after five years through ten years		8,748
	Due after ten years		14,512
	Total	¥	38,904
Maturities of Debt Securities Classified as Held-to-maturity	'
	Maturities of debt securities classified as held-to-maturity at March 31, 2014 are as follows:
		Yen
		(millions)
	Due within one year	¥	22,378
	Due after one year through five years		476
	Due after five years through ten years		10,954
	Due after ten years		842
	Total	¥	34,650
Gross Unrealized Losses on Available-for-sale Securities	'
	Gross unrealized losses on available-for-sale securities and fair value of the related securities, aggregated by length of time that individual securities have been in a continuous unrealized loss position at March 31, 2014 are as follows:
		Yen (millions)
		Fair		Unrealized
		value		losses
	Less than 12 months	¥	8,877	¥	224
	12 months or longer		7,351		553
	Total	¥	16,228	¥	777

Property_on_Operating_Leases_T

Property on Operating Leases (Tables)	12 Months Ended
	Mar. 31, 2014
Future Minimum Lease Rentals Expected to Be Received from Property on Operating Leases	'
	Future minimum lease rentals expected to be received from property on operating leases at March 31, 2014 are as follows:
	Years ending March 31	Yen
		(millions)
	2015	¥	380,146
	2016		247,759
	2017		89,967
	2018		9,148
	2019		2,058
	Total future minimum lease rentals	¥	729,078

Shortterm_and_Longterm_Debt_Ta

Short-term and Long-term Debt (Tables)	12 Months Ended
	Mar. 31, 2014
Short-term Debt	'
	Short-term debt at March 31, 2013 and 2014 is as follows:
		Yen (millions)
		2013		2014
	Short-term bank loans	¥	347,842	¥	373,610
	Asset-backed notes		37,448		69,032
	Medium-term notes		159,963		231,519
	Commercial paper		693,044		645,183
	Total	¥	1,238,297	¥	1,319,344
Long-term Debt	'
	Long-term debt at March 31, 2013 and 2014 is as follows:
		Yen (millions)
		2013		2014
	Honda Motor Co., Ltd.:
	Loans, maturing through 2031:
	Unsecured, principally from banks	¥	160	¥	128
			160		128
	Subsidiaries:
	Loans, maturing through 2029:
	Secured, principally from banks		15,830		30,466
	Unsecured, principally from banks		1,043,857		1,224,947
	Asset-backed notes, maturing through 2019		681,020		808,022
	1.31% Japanese yen unsecured bond due 2013		40,000		—
	1.05% Japanese yen unsecured bond due 2014		30,000		30,000
	0.56% Japanese yen unsecured bond due 2015		30,000		30,000
	0.59% Japanese yen unsecured bond due 2015		30,000		30,000
	0.47% Japanese yen unsecured bond due 2016		40,000		40,000
	0.48% Japanese yen unsecured bond due 2017		40,000		40,000
	0.37% Japanese yen unsecured bond due 2017		30,000		30,000
	0.35% Japanese yen unsecured bond due 2017		35,000		35,000
	0.27% Japanese yen unsecured bond due 2018		30,000		30,000
	0.55% Japanese yen unsecured bond due 2018		—		50,000
	0.32% Japanese yen unsecured bond due 2018		—		40,000
	0.25% Japanese yen unsecured bond due 2019		—		40,000
	0.59% Japanese yen unsecured bond due 2019		10,000		10,000
	0.56% Japanese yen unsecured bond due 2019		15,000		15,000
	0.55% Japanese yen unsecured bond due 2020		10,000		10,000
	0.49% Japanese yen unsecured bond due 2020		—		10,000
	0.43% Japanese yen unsecured bond due 2021		—		10,000
	Medium-term notes, maturing through 2023		1,580,951		2,030,968
	Less unamortized discount, net		5,927		7,001
			3,655,731		4,537,402
	Total long-term debt		3,655,891		4,537,530
	Less current portion		945,046		1,303,464
	Total long-term debt, excluding current portion	¥	2,710,845	¥	3,234,066
Pledged Assets	'
	Pledged assets at March 31, 2013 and 2014 are as follows:
		Yen (millions)
		2013		2014
	Trade accounts and notes receivable	¥	25,528	¥	31,318
	Inventories		11,154		12,908
	Property, plant and equipment		26,169		58,504
	Finance subsidiaries-receivables		724,399		883,776
Maturities of Long-term Debt	'
	The following schedule shows the maturities of long-term debt for each of the five years following March 31, 2014 and thereafter:
	Years ending March 31	Yen
		(millions)
	2015	¥	1,303,464
	2016		963,462
	2017		1,125,196
	2018		391,004
	2019		460,730
	After five years		293,674
			3,234,066
	Total	¥	4,537,530

Other_Liabilities_Tables

Other Liabilities (Tables)	12 Months Ended
	Mar. 31, 2014
Other Liabilities	'
	Other liabilities at March 31, 2013 and 2014 consist of the following:
		Yen (millions)
		2013		2014
	Accrued liabilities for product warranty, excluding current portion	¥	104,584	¥	114,927
	Pension and other postretirement benefits		622,462		445,350
	Deferred income taxes		615,879		706,662
	Other		287,160		296,299
	Total	¥	1,630,085	¥	1,563,238

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Mar. 31, 2014
Total Income Tax Expense (Benefit)	'
	Total income tax expense (benefit) for each of the years in the three-year period ended March 31, 2014 are allocated as follows:
			Yen (millions)
			2012			2013			2014
	Income from continuing operations		¥	135,735		¥	178,976		¥	252,662
	Other comprehensive income (loss) (note 15)			(20,701	)		252			72,486
	Total		¥	115,034		¥	179,228		¥	325,148
Income (Loss) before Income Taxes and Equity in Income of Affiliates by Japanese and Foreign Source	'
	Income (loss) before income taxes and equity in income of affiliates by Japanese and foreign source for each of the years in the three-year period ended March 31, 2014 consisted of the following:
			Yen (millions)
			2012			2013			2014
	Income (loss) before income taxes
	Japanese		¥	(125,787	)	¥	50,450		¥	214,698
	Foreign			383,190			438,441			514,242
	Total		¥	257,403		¥	488,891		¥	728,940
Income Tax Expense (Benefit)	'
	Income tax expense (benefit) for each of the years in the three-year period ended March 31, 2014 consisted of the following:
			Yen (millions)
			2012			2013			2014
	Income taxes
	Current
	Japanese		¥	8,136		¥	(3,666	)	¥	(794	)
	Foreign			77,938			129,390			208,030
	Total		¥	86,074		¥	125,724		¥	207,236
	Deferred
	Japanese		¥	(26,071	)	¥	21,977		¥	54,622
	Foreign			75,732			31,275			(9,196	)
	Total		¥	49,661		¥	53,252		¥	45,426
	Total
	Japanese		¥	(17,935	)	¥	18,311		¥	53,828
	Foreign			153,670			160,665			198,834
	Total		¥	135,735		¥	178,976		¥	252,662
Effective Income Tax Rate	'
	The effective income tax rate for Honda for each of the years in the three-year period ended March 31, 2014 differs from the Japanese statutory income tax rate for the following reasons:
			2012			2013			2014
	Statutory income tax rate			40	%		37.9	%		37.9	%
	Recognition of valuation allowance			7.2			2.2			2.3
	Difference in statutory tax rates of foreign subsidiaries			(12.2	)		(6.7	)		(8.1	)
	Reversal of valuation allowance			(1.8	)		(1.5	)		(0.8	)
	Research and development credit			(0.6	)		(0.7	)		(0.9	)
	Dividend and royalty income from subsidiaries and affiliates, net of foreign tax credit			9.8			4.4			4.7
	Undistributed earnings of subsidiaries and affiliates			2.7			1.8			2
	Other adjustments relating to prior years			0.4			(1.5	)		0.4
	Adjustments for unrecognized tax benefits			(1.1	)		0.2			(3.9	)
	Adjustments for the change in income tax laws*			8.3			0.5			1.2
	Other			0			0			(0.1	)
	Effective tax rate			52.7	%		36.6	%		34.7	%
	*	On November 30, 2011, the National Diet of Japan approved the laws for amendments to previous income tax laws. Upon the change in the laws, the statutory income tax rate in Japan for the year ended March 31, 2013 was changed to 37.9%. The tax rate will be changed to 35.1% for fiscal years beginning on or after April 1, 2015. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net deferred tax assets decreased ¥16,072 million, and income tax expenses increased ¥16,072 million, as of the enactment date of the laws. This impact is included in Adjustments for the change in income tax laws for the year ended March 31, 2012. The impact for the year ended March 31, 2013 is not material.
		On March 20, 2014, the National Diet of Japan approved amendments to existing income tax laws and the Special Reconstruction Corporation Tax imposed on companies will be abolished for fiscal years beginning on or after April 1, 2014. Upon the change in the laws, the statutory income tax rate in Japan for fiscal years beginning on or after April 1, 2014 will be changed to approximately 35%. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net of deferred tax assets decreased ¥7,321 million, and income tax expenses increased ¥7,321 million, as of the enactment date of the laws.
Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities	'
	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at March 31, 2013 and 2014 are presented below:
			Yen (millions)
			2013			2014
	Deferred tax assets:
	Inventories		¥	28,122		¥	30,190
	Allowance for dealers and customers			87,224			110,936
	Accrued bonus			32,380			32,837
	Property, plant and equipment			65,397			58,671
	Operating loss carryforwards			138,559			107,269
	Pension and other postretirement benefits			229,102			152,409
	Other			166,894			188,057
	Total gross deferred tax assets			747,678			680,369
	Less valuation allowance			81,007			97,138
	Net deferred tax assets			666,671			583,231
	Deferred tax liabilities:
	Inventories			(16,575	)		(13,924	)
	Prepaid pension expenses			(12,274	)		(4,977	)
	Property, plant and equipment, excluding lease transactions			(80,103	)		(78,898	)
	Direct financing lease transactions			(23,580	)		(26,658	)
	Operating lease transactions			(623,535	)		(695,507	)
	Undistributed earnings of subsidiaries and affiliates			(89,126	)		(112,085	)
	Net unrealized gains on available-for-sale securities			(27,042	)		(33,709	)
	Other			(51,727	)		(44,887	)
	Total gross deferred tax liabilities			(923,962	)		(1,010,645	)
	Net deferred tax asset (liability)		¥	(257,291	)	¥	(427,414	)
Deferred Income Tax Assets and Liabilities	'
	Deferred income tax assets and liabilities at March 31, 2013 and 2014 are reflected in the consolidated balance sheets under the following captions:
			Yen (millions)
			2013			2014
	Current assets-Deferred income taxes		¥	234,075		¥	202,123
	Other assets			127,248			80,289
	Other current liabilities			(2,735	)		(3,164	)
	Other liabilities			(615,879	)		(706,662	)
	Net deferred tax asset (liability)		¥	(257,291	)	¥	(427,414	)
Operating Loss and Tax Credit Carryforwards	'
	Periods available to offset future taxable income and income taxes vary in each tax jurisdiction and range from one year to an indefinite period as follows:
			Yen
			(millions)
	Operating loss carryforwards:
	Within 1 year		¥	434
	1 to 5 years			12,975
	5 to 20 years			222,937
	Indefinite periods			117,011
	Total		¥	353,357
			Yen
			(millions)
	Tax credit carryforwards:
	Within 1 year		¥	37
	1 to 5 years			17,146
	5 to 20 years			17,076
	Indefinite periods			319
	Total		¥	34,578
Reconciliations of Beginning and Ending Amount of Unrecognized Tax Benefits	'
	Reconciliations of the beginning and ending amount of unrecognized tax benefits for the years ended March 31 are as follows:
			Yen (millions)
			2012			2013			2014
	Balance at beginning of year		¥	46,265		¥	43,627		¥	39,151
	Additions for tax positions related to the current year			2,910			—			—
	Additions for tax positions of prior years			4,538			687			3,332
	Reductions for tax positions of prior years*			(1,217	)		(7,855	)		(26,063	)
	Settlements			(1,688	)		—			(3,808	)
	Reductions for statute of limitations			(6,894	)		—			(6,909	)
	Effect of exchange rate changes			(287	)		2,692			1,280
	Balance at end of year		¥	43,627		¥	39,151		¥	6,983
	*	Due to the Company’s remeasurement based on technical merits regarding transfer pricing matters of overseas transactions between the Company and foreign affiliates, the Company has decreased a portion of unrecognized tax benefits during the year ended March 31, 2014.

Pension_and_Other_Postretireme1

Pension and Other Postretirement Benefits (Tables)	12 Months Ended
	Mar. 31, 2014
Reconciliations of Beginning and Ending Balances of Pension Benefit Obligations and Fair Value of Plan Assets	'
	Reconciliations of beginning and ending balances of the pension benefit obligations and the fair value of the plan assets are as follows:
			Yen (millions)
			Japanese plans						Foreign plans
			2013			2014			2013			2014
	Change in benefit obligations:
	Benefit obligations at beginning of year		¥	(1,193,566	)	¥	(1,283,216	)	¥	(536,064	)	¥	(685,155	)
	Service cost			(31,124	)		(33,701	)		(24,826	)		(27,342	)
	Interest cost			(23,871	)		(19,248	)		(26,107	)		(31,857	)
	Plan participants’ contributions			—			—			(26	)		(13	)
	Actuarial gain (loss)			(82,834	)		(4,833	)		(33,210	)		20,074
	Benefits paid			48,179			47,363			11,177			39,339
	Amendment			—			—			—			57,251
	Curtailment			—			—			—			1,084
	Foreign currency translation			—			—			(76,099	)		(63,053	)
	Benefit obligations at end of year			(1,283,216	)		(1,293,635	)		(685,155	)		(689,672	)
	Change in plan assets:
	Fair value of plan assets at beginning of year			801,701			918,518			422,500			543,164
	Actual return on plan assets			94,446			71,304			45,124			67,666
	Employer contributions			70,550			69,580			23,795			33,557
	Plan participants’ contributions			—			—			26			13
	Benefits paid			(48,179	)		(47,363	)		(11,177	)		(39,339	)
	Foreign currency translation			—			—			62,896			51,891
	Fair value of plan assets at end of year			918,518			1,012,039			543,164			656,952
	Funded status		¥	(364,698	)	¥	(281,596	)	¥	(141,991	)	¥	(32,720	)
	Amounts recognized in the consolidated balance sheets consist of:
	Noncurrent assets		¥	1,480		¥	2,626		¥	—		¥	18,643
	Current liabilities			(364	)		(335	)		(38	)		(40	)
	Noncurrent liabilities			(365,814	)		(283,887	)		(141,953	)		(51,323	)
	Total		¥	(364,698	)	¥	(281,596	)	¥	(141,991	)	¥	(32,720	)
	Amounts recognized in accumulated other comprehensive income (loss) consist of:
	Actuarial loss (gain)		¥	394,998		¥	335,886		¥	206,941		¥	145,979
	Net transition obligation			—			—			77			35
	Prior service cost (benefit)			(121,671	)		(105,367	)		(1,905	)		(35,497	)
	Total		¥	273,327		¥	230,519		¥	205,113		¥	110,517
	Pension plans with accumulated benefit obligations in excess of plan assets:
	Projected benefit obligations		¥	(1,262,263	)	¥	(1,272,687	)	¥	(493,040	)	¥	(469,569	)
	Accumulated benefit obligations			(1,180,781	)		(1,191,640	)		(453,165	)		(469,152	)
	Fair value of plan assets			897,066			988,744			367,949			429,441
Pension Expense and Other Amounts Recognized in Other Comprehensive Income (Loss)	'
	Pension expense and other amounts recognized in other comprehensive income (loss) for each of the years in the three-year period ended March 31, 2014 include the following:
			Yen (millions)
			2012			2013			2014
	Japanese plans:
	Pension cost
	Service cost-benefits earned during the year		¥	33,454		¥	31,124		¥	33,701
	Interest cost on projected benefit obligations			23,481			23,871			19,248
	Expected return on plan assets			(23,645	)		(24,048	)		(25,341	)
	Amortization of actuarial loss (gain)			20,373			18,149			17,218
	Amortization of prior service cost (benefit)			(16,304	)		(16,304	)		(16,304	)
	Total		¥	37,359		¥	32,792		¥	28,522
	Other amounts recognized in other comprehensive income (loss)
	Actuarial loss (gain)		¥	(13,305	)	¥	10,137		¥	(41,894	)
	Amortization of actuarial loss (gain)			(20,373	)		(18,149	)		(17,218	)
	Amortization of prior service cost (benefit)			16,304			16,304			16,304
	Total			(17,374	)		8,292			(42,808	)
	Total recognized in pension cost and other comprehensive income (loss)		¥	19,985		¥	41,084		¥	(14,286	)
	Foreign plans:
	Pension cost
	Service cost-benefits earned during the year		¥	19,506		¥	24,826		¥	27,342
	Interest cost on projected benefit obligations			24,130			26,107			31,857
	Expected return on plan assets			(26,796	)		(30,254	)		(39,624	)
	Amortization of actuarial loss (gain)			5,829			10,724			12,538
	Amortization of net transition obligation			30			33			42
	Amortization of prior service cost (benefit)			6			(205	)		(2,291	)
	Curtailment gain			—			—			(21,368	)
	Other			3			17			—
	Total		¥	22,708		¥	31,248		¥	8,496
	Other amounts recognized in other comprehensive income (loss)
	Actuarial loss (gain)		¥	71,160		¥	16,466		¥	(48,424	)
	Amortization of actuarial loss (gain)			(5,829	)		(10,724	)		(12,538	)
	Amortization of net transition obligation			(30	)		(33	)		(42	)
	Prior service cost (benefit)			(2,677	)		41			(57,251	)
	Amortization of prior service cost (benefit)			(6	)		205			2,291
	Curtailment gain			—			—			21,368
	Total			62,618			5,955			(94,596	)
	Total recognized in pension cost and other comprehensive income (loss)		¥	85,326		¥	37,203		¥	(86,100	)
Estimated Amounts to Be Amortized from Accumulated Other Comprehensive Income (Loss) into Net Periodic Benefit Cost over Next Fiscal Year	'
	The following table presents the estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost over the next fiscal year.
			Yen (millions)
			Japanese			Foreign
			plans			plans
	Amortization of actuarial loss (gain)		¥	13,451		¥	12,019
	Amortization of net transition obligation			—			3
	Amortization of prior service cost (benefit)			(16,304	)		(3,371	)
Estimated Future Gross Benefit Payments	'
	The following table presents estimated future gross benefit payments:
	Years ending March 31		Yen (millions)
			Japanese			Foreign
			plans			plans
	2015		¥	46,670		¥	23,297
	2016			47,386			24,904
	2017			48,683			26,797
	2018			50,984			29,143
	2019			53,616			32,020
	2020-2024			298,741			198,433
Benefit obligation	'
Weighted-average Assumptions	'
	Weighted-average assumptions used to determine benefit obligation at March 31, 2013 and 2014 were as follows:
			2013			2014
	Japanese plans:
	Discount rate			1.5	%		1.5	%
	Rate of salary increase			2.2	%		2.2	%
	Foreign plans:
	Discount rate			4.5 ~  4.7	%		4.6 ~  4.8	%
	Rate of salary increase			2.5 ~  4.1	%		2.5 ~  3.9	%
Net periodic benefit cost	'
Weighted-average Assumptions	'
	Weighted-average assumptions used to determine net periodic benefit cost for each of the years in the three-year period ended March 31, 2014 were as follows:
			2012			2013			2014
	Japanese plans:
	Discount rate			2	%		2	%		1.5	%
	Rate of salary increase			2.2	%		2.1	%		2.2	%
	Expected long-term rate of return			3	%		3	%		3	%
	Foreign plans:
	Discount rate			5.5 ~ 6.0	%		4.6 ~ 5.2	%		4.5 ~ 4.7	%
	Rate of salary increase			1.5 ~ 4.6	%		1.5 ~ 4.4	%		2.5 ~ 4.1	%
	Expected long-term rate of return			6.5 ~ 7.5	%		6.2 ~ 7.7	%		6.0 ~ 7.4	%
Japanese plans	'
Fair Value of Pension Plan Assets by Asset Category	'
	The following tables present the fair value of the Japanese pension plan assets by asset category as of March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents		¥	25,534		¥	—		¥	—		¥	25,534
	Equity securities			312,764			263			—			313,027
	Corporate bonds			4,320			5,477			18			9,815
	Government, agency and local bonds			93,450			217,964			163			311,577
	Group annuity insurance:
	General accounts			—			21,042			—			21,042
	Separate accounts			—			10,773			—			10,773
	Pooled funds:
	Hedge funds			—			—			85,391			85,391
	Commingled and other mutual funds			2,033			135,619			1,213			138,865
	Derivative instruments			81			2,413			—			2,494
	Total		¥	438,182		¥	393,551		¥	86,785		¥	918,518
			Yen (millions)
	As of March 31, 2014		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents		¥	20,438		¥	—		¥	—		¥	20,438
	Equity securities			349,601			254			2			349,857
	Corporate bonds			8,341			1,829			86			10,256
	Government, agency and local bonds			256,114			107,491			—			363,605
	Group annuity insurance:
	General accounts			—			23,688			—			23,688
	Separate accounts			—			11,625			—			11,625
	Pooled funds:
	Hedge funds			—			—			95,860			95,860
	Commingled and other mutual funds			1,559			137,078			1,286			139,923
	Derivative instruments			16			(3,229	)		—			(3,213	)
	Total		¥	636,069		¥	278,736		¥	97,234		¥	1,012,039
	*	Information about the three hierarchy levels is described in note 16.
Reconciliations for Level 3 Pension Plan Assets	'
	The following tables present reconciliations during the years ended March 31, 2013 and 2014 for Level 3 Japanese pension plan assets.
			Yen (millions)
			Equity			Corporate			Government,			Pooled funds					Total
			securities			bonds			agency and
	For the year ended March 31, 2013								local bonds			Hedge			Commingled
												funds			and other
															mutual
															funds
	Balance at beginning of year		¥	180		¥	—		¥	100		¥	63,271		¥	—	¥	63,551
	Actual return on plan assets:
	Relating to assets still held at the reporting date			—			—			22			10,484			13		10,519
	Relating to assets sold during the period			60			—			1			804			—		865
	Purchases, sales and settlements, net			(240	)		18			40			10,832			1,200		11,850
	Transfers in and/or out of Level 3			—			—			—			—			—		—
	Balance at end of year		¥	—		¥	18		¥	163		¥	85,391		¥	1,213	¥	86,785
			Yen (millions)
			Equity			Corporate			Government,			Pooled funds					Total
			securities			bonds			agency and
	For the year ended March 31, 2014								local bonds			Hedge			Commingled
												funds			and other
															mutual
															funds
	Balance at beginning of year		¥	—		¥	18		¥	163		¥	85,391		¥	1,213	¥	86,785
	Actual return on plan assets:
	Relating to assets still held at the reporting date			—			4			—			9,600			73		9,677
	Relating to assets sold during the period			—			—			3			644			—		647
	Purchases, sales and settlements, net			2			64			(139	)		225			—		152
	Transfers in and/or out of Level 3			—			—			(27	)		—			—		(27	)
	Balance at end of year		¥	2		¥	86		¥	—		¥	95,860		¥	1,286	¥	97,234
Foreign plans	'
Fair Value of Pension Plan Assets by Asset Category	'
	The following tables present the fair value of the foreign pension plan assets by asset category as of March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents		¥	6,178		¥	—		¥	—		¥	6,178
	Short-term investments			742			10,787			—			11,529
	Equity securities			157,704			—			—			157,704
	Corporate bonds			—			51,660			282			51,942
	Government, agency and local bonds			2,868			42,416			373			45,657
	Pooled funds:
	Real estate funds			—			—			26,995			26,995
	Private equity funds			—			—			22,946			22,946
	Hedge funds			—			—			28,695			28,695
	Commingled and other mutual funds			309			176,534			10,788			187,631
	Derivative instruments			—			130			(73	)		57
	Asset-backed securities			—			3,830			—			3,830
	Total		¥	167,801		¥	285,357		¥	90,006		¥	543,164
			Yen (millions)
	As of March 31, 2014		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents		¥	6,597		¥	—		¥	—		¥	6,597
	Short-term investments			462			11,891			—			12,353
	Equity securities			201,787			3,514			—			205,301
	Corporate bonds			—			61,883			266			62,149
	Government, agency and local bonds			4,170			54,136			49			58,355
	Pooled funds:
	Real estate funds			—			—			35,856			35,856
	Private equity funds			—			—			33,215			33,215
	Hedge funds			—			—			35,807			35,807
	Commingled and other mutual funds			—			184,288			17,091			201,379
	Derivative instruments			(704	)		1,475			(6	)		765
	Asset-backed securities			—			5,175			—			5,175
	Total		¥	212,312		¥	322,362		¥	122,278		¥	656,952
	*	Information about the three hierarchy levels is described in note 16.
Reconciliations for Level 3 Pension Plan Assets	'
	The following tables present reconciliations during the years ended March 31, 2013 and 2014 for Level 3 foreign pension plan assets.
			Yen (millions)
									Pooled funds
	For the year ended March 31, 2013		Corporate			Government,			Real			Private			Hedge		Commingled			Derivative			Total
			bonds			agency and			estate			equity			funds		and other			instruments
						local bonds			funds			funds					mutual
																	funds
	Balance at beginning of year		¥	—		¥	—		¥	15,190		¥	10,030		¥	19,726	¥	1,840		¥	(28	)	¥	46,758
	Actual return on plan assets:
	Relating to assets still held at the reporting date			(2	)		7			1,010			898			1,537		606			2			4,058
	Relating to assets sold during the period			11			7			(2	)		291			3		—			7			317
	Purchases, sales and settlements, net			70			95			7,935			9,056			3,869		7,438			(45	)		28,418
	Transfers in and/or out of Level 3			171			219			—			—			—		—			—			390
	Foreign currency translation			32			45			2,862			2,671			3,560		904			(9	)		10,065
	Balance at end of year		¥	282		¥	373		¥	26,995		¥	22,946		¥	28,695	¥	10,788		¥	(73	)	¥	90,006
			Yen (millions)
									Pooled funds
	For the year ended March 31, 2014		Corporate			Government,			Real			Private			Hedge		Commingled			Derivative			Total
			bonds			agency and			estate			equity			funds		and other			instruments
						local bonds			funds			funds					mutual
																	funds
	Balance at beginning of year		¥	282		¥	373		¥	26,995		¥	22,946		¥	28,695	¥	10,788		¥	(73	)	¥	90,006
	Actual return on plan assets:
	Relating to assets still held at the reporting date			(12	)		2			2,403			1,778			3,217		353			—			7,741
	Relating to assets sold during the period			(3	)		—			2			401			—		—			1			401
	Purchases, sales and settlements, net			21			45			3,499			6,355			1,075		3,539			71			14,605
	Transfers in and/or out of Level 3			(48	)		(397	)		—			—			—		—			—			(445	)
	Foreign currency translation			26			26			2,957			1,735			2,820		2,411			(5	)		9,970
	Balance at end of year		¥	266		¥	49		¥	35,856		¥	33,215		¥	35,807	¥	17,091		¥	(6	)	¥	122,278

Supplemental_Disclosures_of_Ca1

Supplemental Disclosures of Cash Flow Information (Tables)	12 Months Ended
	Mar. 31, 2014
Supplemental Disclosures of Cash Flow Information	'
		Yen (millions)
		2012		2013		2014
	Cash paid (provided), net during the year for:
	Interest	¥	97,788	¥	86,989	¥	82,796
	Income taxes		47,217		138,583		240,668

Other_Comprehensive_Income_Los1

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Mar. 31, 2014
Changes in Accumulated Other Comprehensive Income (Loss) by Component	'
	The following tables present the changes in accumulated other comprehensive income (loss) by component for the years ended March 31, 2012, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2012		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(1,268,233	)	¥	30,299		¥	(156	)	¥	(257,290	)	¥	(1,495,380	)
	Other comprehensive income (loss) before reclassifications			(118,135	)		6,351			(76	)		(46,543	)		(158,403	)
	Amounts reclassified from accumulated other comprehensive income (loss)			—			(539	)		47			6,890			6,398
	Net current-period other comprehensive income (loss)			(118,135	)		5,812			(29	)		(39,653	)		(152,005	)
	Less: Other comprehensive income attributable to noncontrolling interests			(1,323	)		(87	)		—			103			(1,307	)
	Balance at end of year		¥	(1,385,045	)	¥	36,198		¥	(185	)	¥	(297,046	)	¥	(1,646,078	)
			Yen (millions)
	For the year ended March 31, 2013		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(1,385,045	)	¥	36,198		¥	(185	)	¥	(297,046	)	¥	(1,646,078	)
	Other comprehensive income (loss) before reclassifications			430,812			7,968			(797	)		(24,534	)		413,449
	Amounts reclassified from accumulated other comprehensive income (loss)			—			16			745			9,237			9,998
	Net current-period other comprehensive income (loss)			430,812			7,984			(52	)		(15,297	)		423,447
	Less: Other comprehensive income attributable to noncontrolling interests			15,350			51			—			(1,240	)		14,161
	Balance at end of year		¥	(969,583	)	¥	44,131		¥	(237	)	¥	(311,103	)	¥	(1,236,792	)
			Yen (millions)
	For the year ended March 31, 2014		Adjustments from			Unrealized gains			Unrealized gains			Pension and other			Total
			foreign currency			(losses) on			(losses) on			postretirement
			translation			available-for-sale			derivative			benefits adjustments
						securities, net			instruments, net
	Balance at beginning of year		¥	(969,583	)	¥	44,131		¥	(237	)	¥	(311,103	)	¥	(1,236,792	)
	Other comprehensive income (loss) before reclassifications			333,022			15,975			(19	)		112,952			461,930
	Amounts reclassified from accumulated other comprehensive income (loss)			637			(723	)		256			(5,234	)		(5,064	)
	Net current-period other comprehensive income (loss)			333,659			15,252			237			107,718			456,866
	Less: Other comprehensive income attributable to noncontrolling interests			13,235			33			—			(180	)		13,088
	Balance at end of year		¥	(649,159	)	¥	59,350		¥	—		¥	(203,205	)	¥	(793,014	)
Reclassifications out of Accumulated Other Comprehensive Income (Loss) by Component	'
	The following table presents the reclassifications out of accumulated other comprehensive income (loss) by component for the year ended March 31, 2014.
	For the year ended March 31, 2014		Yen (millions)
	Details about accumulated other comprehensive income		Amounts reclassified			Affected line items in the statement where net
	(loss) components		from accumulated other			income is presented
			comprehensive income
			(loss)
	Adjustments from foreign currency translation
			¥	(1,027	)	Other income (expenses) – Other, net
				390		Income tax expense
			¥	(637	)	Net income
	Unrealized gains (losses) on available-for-sale securities, net
			¥	1,114		Other income (expenses) – Other, net
				(391	)	Income tax expense
			¥	723		Net income
	Unrealized gains (losses) on derivative instruments, net
			¥	(411	)	Other income (expenses) – Other, net
				155		Income tax expense
			¥	(256	)	Net income
	Pension and other postretirement benefits adjustments
			¥	8,823		*
				(3,589	)	Income tax expense
			¥	5,234		Net income
	Total reclassifications for the period		¥	5,064
	*	This accumulated other comprehensive income (loss) components is included in the computation of net periodic pension cost.
Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss) and Reclassification Adjustments	'
	The following tables present the tax effects allocated to each component of other comprehensive income (loss) and reclassification adjustments for the years ended March 31, 2012, 2013 and 2014.
			Yen (millions)
	For the year ended March 31, 2012		Before-tax			Tax			Net-of-tax
						(expense)
						or benefit
						(note 11)
	Adjustments from foreign currency translation:
	Unrealized gains (losses) arising during the year		¥	(119,910	)	¥	1,775		¥	(118,135	)
	Reclassification adjustments for losses (gains) realized in net income			—			—			—
	Net unrealized gains (losses)			(119,910	)		1,775			(118,135	)
	Unrealized gains (losses) on available-for-sale securities:
	Unrealized holding gains (losses) arising during the year			9,438			(3,087	)		6,351
	Reclassification adjustments for losses (gains) realized in net income			(706	)		167			(539	)
	Net unrealized gains (losses)			8,732			(2,920	)		5,812
	Unrealized gains (losses) on derivative instruments:
	Unrealized holding gains (losses) arising during the year			(115	)		39			(76	)
	Reclassification adjustments for losses (gains) realized in net income			78			(31	)		47
	Net unrealized gains (losses)			(37	)		8			(29	)
	Pension and other postretirement benefits adjustments*:
	(Increase) decrease in net unrealized losses on pension and other postretirement benefits			(72,225	)		25,682			(46,543	)
	Amortization of unrealized (gain) loss on pension and other postretirement benefits			10,734			(3,844	)		6,890
	Net unrealized gains (losses)			(61,491	)		21,838			(39,653	)
	Other comprehensive income (loss)		¥	(172,706	)	¥	20,701		¥	(152,005	)
			Yen (millions)
	For the year ended March 31, 2013		Before-tax			Tax			Net-of-tax
						(expense)
						or benefit
						(note 11)
	Adjustments from foreign currency translation:
	Unrealized gains (losses) arising during the year		¥	433,640		¥	(2,828	)	¥	430,812
	Reclassification adjustments for losses (gains) realized in net income			—			—			—
	Net unrealized gains (losses)			433,640			(2,828	)		430,812
	Unrealized gains (losses) on available-for-sales securities:
	Unrealized holding gains (losses) arising during the year			12,336			(4,368	)		7,968
	Reclassification adjustments for losses (gains) realized in net income			24			(8	)		16
	Net unrealized gains (losses)			12,360			(4,376	)		7,984
	Unrealized gains (losses) on derivative instruments:
	Unrealized holding gains (losses) arising during the year			(1,281	)		484			(797	)
	Reclassification adjustments for losses (gains) realized in net income			1,197			(452	)		745
	Net unrealized gains (losses)			(84	)		32			(52	)
	Pension and other postretirement benefits adjustments*:
	(Increase) decrease in net unrealized losses on pension and other postretirement benefits			(36,611	)		12,077			(24,534	)
	Amortization of unrealized (gain) loss on pension and other postretirement benefits			14,394			(5,157	)		9,237
	Net unrealized gains (losses)			(22,217	)		6,920			(15,297	)
	Other comprehensive income (loss)		¥	423,699		¥	(252	)	¥	423,447
			Yen (millions)
	For the year ended March 31, 2014		Before-tax			Tax			Net-of-tax
						(expense)
						or benefit
						(note 11)
	Adjustments from foreign currency translation:
	Unrealized gains (losses) arising during the year		¥	343,695		¥	(10,673	)	¥	333,022
	Reclassification adjustments for losses (gains) realized in net income			1,027			(390	)		637
	Net unrealized gains (losses)			344,722			(11,063	)		333,659
	Unrealized gains (losses) on available-for-sale securities:
	Unrealized holding gains (losses) arising during the year			22,261			(6,286	)		15,975
	Reclassification adjustments for losses (gains) realized in net income			(1,114	)		391			(723	)
	Net unrealized gains (losses)			21,147			(5,895	)		15,252
	Unrealized gains (losses) on derivative instruments:
	Unrealized holding gains (losses) arising during the year			(29	)		10			(19	)
	Reclassification adjustments for losses (gains) realized in net income			411			(155	)		256
	Net unrealized gains (losses)			382			(145	)		237
	Pension and other postretirement benefits adjustments*:
(Increase) decrease in net unrealized losses on pension and other postretirement benefits			171,924			(58,972	)		112,952
Amortization of unrealized (gain) loss on pension and other postretirement benefits			(8,823	)		3,589			(5,234	)
Net unrealized gains (losses)			163,101			(55,383	)		107,718
Other comprehensive income (loss)		¥	529,352		¥	(72,486	)	¥	456,866
*	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Mar. 31, 2014
Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	The following tables present the assets and liabilities measured at fair value on a recurring basis as of March 31, 2013 and 2014.
			Yen (millions)
	As of March 31, 2013		Level 1			Level 2			Level 3			Gross			Netting			Net
												fair value			adjustment			amount
	Assets:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	6,538		¥	—		¥	6,538		¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			32,152			—			32,152			—			—
	Total derivative instruments			—			38,690			—			38,690			(18,071	)		20,619
	Available-for-sale securities
	Marketable equity securities			117,110			—			—			117,110			—			117,110
	Auction rate securities			—			—			6,928			6,928			—			6,928
	Debt securities			—			4,226			—			4,226			—			4,226
	Others			584			—			—			584			—			584
	Total available-for-sale securities			117,694			4,226			6,928			128,848			—			128,848
	Total		¥	117,694		¥	42,916		¥	6,928		¥	167,538		¥	(18,071	)	¥	149,467
	Liabilities:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	(78,934	)	¥	—		¥	(78,934	)	¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			(14,639	)		—			(14,639	)		—			—
	Total derivative instruments			—			(93,573	)		—			(93,573	)		18,071			(75,502	)
	Total		¥	—		¥	(93,573	)	¥	—		¥	(93,573	)	¥	18,071		¥	(75,502	)
			Yen (millions)
	As of March 31, 2014		Level 1			Level 2			Level 3			Gross			Netting			Net
												fair value			adjustment			amount
	Assets:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	11,036		¥	—		¥	11,036		¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			19,814			—			19,814			—			—
	Total derivative instruments			—			30,850			—			30,850			(10,804	)		20,046
	Available-for-sale securities
	Marketable equity securities			138,476			—			—			138,476			—			138,476
	Auction rate securities			—			—			6,999			6,999			—			6,999
	Debt securities			—			31,905			—			31,905			—			31,905
	Others			5,146			3,434			—			8,580			—			8,580
	Total available-for-sale securities			143,622			35,339			6,999			185,960			—			185,960
	Total		¥	143,622		¥	66,189		¥	6,999		¥	216,810		¥	(10,804	)	¥	206,006
	Liabilities:
	Derivative instruments
	Foreign exchange instruments (notes 1(q) and 17)		¥	—		¥	(14,852	)	¥	—		¥	(14,852	)	¥	—		¥	—
	Interest rate instruments (notes 1(q) and 17)			—			(10,887	)		—			(10,887	)		—			—
	Total derivative instruments			—			(25,739	)		—			(25,739	)		10,804			(14,935	)
	Total		¥	—		¥	(25,739	)	¥	—		¥	(25,739	)	¥	10,804		¥	(14,935	)
Reconciliations for All Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	The following tables present reconciliations during the years ended March 31, 2013 and 2014 for all Level 3 assets and liabilities measured at fair value on a recurring basis.
			Yen
			(millions)
	For the year ended March 31, 2013		Auction rate
			securities
	Balance at beginning of year		¥	6,651
	Total realized/unrealized gains or losses
	Included in earnings			—
	Included in other comprehensive income (loss)			115
	Purchases, issuances, settlements and sales
	Purchases			—
	Issuances			—
	Settlements			—
	Sales			(691	)
	Foreign currency translation			853
	Balance at end of year		¥	6,928
	The amounts of total gains or losses for the period attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date
	Included in earnings		¥	—
	Included in other comprehensive income (loss)			115
			Yen
			(millions)
	For the year ended March 31, 2014		Auction rate
			securities
	Balance at beginning of year		¥	6,928
	Total realized/unrealized gains or losses
	Included in earnings			—
	Included in other comprehensive income (loss)			202
	Purchases, issuances, settlements and sales
	Purchases			—
	Issuances			—
	Settlements			—
	Sales			(790	)
	Foreign currency translation			659
	Balance at end of year		¥	6,999
	The amounts of total gains or losses for the period attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date
	Included in earnings		¥	—
	Included in other comprehensive income (loss)			103
Estimated Fair Values of Significant Financial Instruments	'
	The estimated fair values of significant financial instruments at March 31, 2013 and 2014 are as follows:
			Yen (millions)
			2013						2014
			Carrying			Estimated			Carrying			Estimated
			amount			fair value			amount			fair value
	Finance subsidiaries-receivables*		¥	4,278,460		¥	4,326,333		¥	5,140,064		¥	5,175,564
	Held-to-maturity securities			16,511			16,556			34,650			34,667
	Debt			(4,894,188	)		(4,966,318	)		(5,856,874	)		(5,917,087	)
	*	The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table exclude ¥425,870 million and ¥393,933 million, respectively, of direct financing leases, net, classified as finance subsidiaries-receivables in the consolidated balance sheets. The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table also include ¥673,193 million and ¥752,229 million of finance receivables classified as trade accounts and notes receivable and other assets in the consolidated balance sheets, respectively.

Risk_Management_Activities_and1

Risk Management Activities and Derivative Financial Instruments (Tables)	12 Months Ended
	Mar. 31, 2014
Contract Amounts Outstanding for Foreign Exchange Instruments and Notional Principal Amounts of Interest Rate Instruments	'
	Contract amounts outstanding for foreign currency forward exchange contracts, foreign currency option contracts and currency swap agreements and the notional principal amounts of interest rate swap agreements at March 31, 2013 and 2014 are as follows:
	Derivatives designated as hedging instruments
		Yen (millions)
		2013				2014
	Foreign currency forward exchange contracts	¥	23,324			¥	—
	Total foreign exchange instruments	¥	23,324			¥	—
	Derivatives not designated as hedging instruments
		Yen (millions)
		2013				2014
	Foreign currency forward exchange contracts	¥	724,435			¥	506,734
	Foreign currency option contracts		4,145				3,721
	Currency swap agreements		337,254				366,031
	Total foreign exchange instruments	¥	1,065,834			¥	876,486
	Interest rate swap agreements	¥	4,063,289			¥	4,809,037
	Total interest rate instruments	¥	4,063,289			¥	4,809,037
Estimated Fair Values of Derivative Instruments	'
	The estimated fair values of derivative instruments at March 31, 2013 and 2014 are as follows.
	As of March 31, 2013
	Derivatives designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	—			¥	(211)			¥	—		¥	—		¥	(211)
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	6,538			¥	(78,723	)		¥	(1,534	)	¥	(314	)	¥	(70,337	)
	Interest rate instruments		32,152				(14,639	)			3,907			18,560			(4,954	)
	Total	¥	38,690			¥	(93,362	)		¥	2,373		¥	18,246		¥	(75,291	)
	Netting adjustment		(18,071	)			18,071
	Net amount	¥	20,619			¥	(75,291	)
	As of March 31, 2014
	Derivatives designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	—			¥	—			¥	—		¥	—		¥	—
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gross fair value								Balance sheet location
		Asset				Liability				Other			Other			Other
		derivatives				derivatives				current			assets			current
										assets						liabilities
	Foreign exchange instruments	¥	11,036			¥	(14,852	)		¥	4,910		¥	2,288		¥	(11,014	)
	Interest rate instruments		19,814				(10,887	)			593			12,255			(3,921	)
	Total	¥	30,850			¥	(25,739	)		¥	5,503		¥	14,543		¥	(14,935	)
	Netting adjustment		(10,804	)			10,804
	Net amount	¥	20,046			¥	(14,935	)
Pre-tax Effects of Derivative Instruments on the Company's Results of Operations	'
	The pre-tax effects of derivative instruments on the Company’s results of operations for each of the years in the three-year period ended March 31, 2014 are as follows:
	For the year ended March 31, 2012
	Derivatives designated as hedging instruments
	Cash flow hedges:
		Yen (millions)
		Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
		recognized in other				accumulated other comprehensive						earnings (financial
		comprehensive				income (loss) into earnings						instruments’ time value
		income (loss)				(effective portion)						component excluded from
		(effective portion)										the assessment of hedge effectiveness)
		Amount				Location		Amount				Location	Amount
	Foreign exchange instruments	¥	-115			Other income		¥	-78			Other income	¥	-455
						(expenses) – Other, net						(expenses) – Other, net
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gain (Loss) recognized in earnings
		Location		Amount
	Foreign exchange instruments	Other income (expenses) – Other, net		¥	(3,709	)
	Interest rate instruments	Other income (expenses) –  Other, net			(1,421	)
	Total			¥	(5,130	)
	For the year ended March 31, 2013
	Derivatives designated as hedging instruments
	Cash flow hedges:
		Yen (millions)
		Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
		recognized in other				accumulated other comprehensive						earnings (financial
		comprehensive				income (loss) into earnings						instruments’ time value
		income (loss)				(effective portion)						component excluded from
		(effective portion)										the assessment of hedge effectiveness)
		Amount				Location		Amount				Location	Amount
	Foreign exchange instruments	¥	-1,281			Other income		¥	-1,197			Other income	¥	-589
						(expenses) – Other, net						(expenses) – Other, net
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gain (Loss) recognized in earnings
		Location		Amount
	Foreign exchange instruments	Other income (expenses) – Other, net		¥	(111,004	)
	Interest rate instruments	Other income (expenses) – Other, net			3,212
	Total			¥	(107,792	)
	For the year ended March 31, 2014
	Derivatives designated as hedging instruments
	Cash flow hedges:
		Yen (millions)
		Gain (Loss)				Gain (Loss) reclassified from						Gain (Loss) recognized in
		recognized in other				accumulated other comprehensive						earnings (financial
		comprehensive				income (loss) into earnings						instruments’ time value
		income (loss)				(effective portion)						component excluded from
		(effective portion)										the assessment of hedge effectiveness)
		Amount				Location		Amount				Location	Amount
	Foreign exchange instruments	¥	-29			Other income		¥	-411			Other income	¥	-714
						(expenses) – Other, net						(expenses) – Other, net
	Derivatives not designated as hedging instruments
		Yen (millions)
		Gain (Loss) recognized in earnings
		Location		Amount
	Foreign exchange instruments	Other income (expenses) – Other, net		¥	(23,765	)
	Interest rate instruments	Other income (expenses) – Other, net			(10,547	)
	Total			¥	(34,312	)

Commitments_and_Contingent_Lia1

Commitments and Contingent Liabilities (Tables)	12 Months Ended
	Mar. 31, 2014
Changes in Accrued Liabilities for Product Warranties	'
	The changes in the accrued liabilities for those product warranties for each of the years in the two-year period ended March 31, 2014 are as follows:
		Yen (millions)
		2013			2014
	Balance at beginning of year	¥	170,562		¥	208,033
	Warranty claims paid during the period		(64,942	)		(104,090	)
	Liabilities accrued for warranties issued during the period		97,108			153,898
	Changes in liabilities for pre-existing warranties during the period		(8,583	)		397
	Foreign currency translation		13,888			11,382
	Balance at end of year	¥	208,033		¥	269,620

Leases_Tables

Leases (Tables)	12 Months Ended
	Mar. 31, 2014
Future Minimum Lease Payments under Noncancelable Operating Leases	'
	Future minimum lease payments under noncancelable operating leases that have initial or remaining lease terms in excess of one year at March 31, 2014 are as follows:
	Years ending March 31	Yen
		(millions)
	2015	¥	18,862
	2016		14,466
	2017		13,101
	2018		8,423
	2019		7,604
	After five years		39,724
	Total minimum lease payments	¥	102,180

Valuation_and_Qualifying_Accou1

Valuation and Qualifying Accounts (Tables)	12 Months Ended
	Mar. 31, 2014
Valuation and Qualifying Accounts	'
	The valuation and qualifying accounts for the years ended March 31, 2012, 2013 and 2014 are set forth in the following table:
			Yen (millions)
					Additions
			Balance at		Charged to		Charged		Deductions*		Foreign			Balance at
			beginning		costs and		to other				currency			end of
			of year		expenses		accounts				translation			year
	March 31, 2012:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,904	¥	3,773		—	¥	3,858	¥	(526	)	¥	7,293
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	24,890	¥	11,625		—	¥	15,484	¥	(415	)	¥	20,616
	Allowance for losses on lease residual values			7,225		1,407		—		2,954		(312	)		5,366
			¥	32,115	¥	13,032		—	¥	18,438	¥	(727	)	¥	25,982
	Other assets
	Allowance for doubtful accounts		¥	23,275	¥	1,293		—	¥	1,311	¥	(221	)	¥	23,036
	Deferred tax assets
	Valuation allowance		¥	65,479	¥	18,665		—	¥	4,651	¥	(10,401	)	¥	69,092
	March 31, 2013:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,293	¥	2,810		—	¥	2,721	¥	503		¥	7,885
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	20,616	¥	9,234		—	¥	13,198	¥	1,176		¥	17,828
	Allowance for losses on lease residual values			5,366		825		—		3,178		341			3,354
			¥	25,982	¥	10,059		—	¥	16,376	¥	1,517		¥	21,182
	Other assets
	Allowance for doubtful accounts		¥	23,036	¥	687		—	¥	1,063	¥	94		¥	22,754
	Deferred tax assets
	Valuation allowance		¥	69,092	¥	9,570	¥	1,171	¥	7,347	¥	8,521		¥	81,007
	March 31, 2014:
	Trade accounts and notes receivable
	Allowance for doubtful accounts		¥	7,885	¥	3,290		—	¥	2,094	¥	596		¥	9,677
	Finance subsidiaries-receivables
	Allowance for credit losses		¥	17,828	¥	18,503		—	¥	16,136	¥	1,364		¥	21,559
	Allowance for losses on lease residual values			3,354		401		—		1,671		47			2,131
			¥	21,182	¥	18,904		—	¥	17,807	¥	1,411		¥	23,690
	Other assets
	Allowance for doubtful accounts		¥	22,754	¥	175		—	¥	881	¥	52		¥	22,100
	Deferred tax assets
	Valuation allowance		¥	81,007	¥	16,488		—	¥	6,710	¥	6,353		¥	97,138
	*	Receivable: Bad debts written off
	Deferred tax assets:		Reversal of valuation allowance. Deductions in valuation allowance for the years ended March 31, 2012 and 2014 include a portion credited to other comprehensive income of ¥1,650 million and ¥1,173 million, respectively. Deductions in valuation allowance in the three-year period ended March 31, 2014 related to deferred tax assets that expired unused are immaterial.

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	Mar. 31, 2014
Principal Products and Services, and Functions of Each Segment	'
	Principal products and services, and functions of each segment are as follows:
	Segment		Principal products and services		Functions
	Motorcycle Business		Motorcycles, all-terrain vehicles (ATVs) and relevant parts		Research & Development
					Manufacturing
					Sales and related services
	Automobile Business		Automobiles and relevant parts		Research & Development
					Manufacturing
					Sales and related services
	Financial Services Business		Financial, insurance services		Retail loan and lease related to
					Honda products
					Others
	Power Product and Other Businesses		Power products and relevant parts, and others		Research & Development
					Manufacturing
					Sales and related services
					Others
Segment Information	'
	Segment Information
	As of and for the year ended March 31, 2012
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
	External customers		¥	1,348,828		¥	5,805,975		¥	516,148		¥	277,144		¥	7,948,095	¥	—		¥	7,948,095
	Intersegment			—			16,767			10,428			12,590			39,785		(39,785	)		—
	Total		¥	1,348,828		¥	5,822,742		¥	526,576		¥	289,734		¥	7,987,880	¥	(39,785	)	¥	7,948,095
	Cost of sales, SG&A and R&D expenses			1,206,226			5,899,948			356,570			293,772			7,756,516		(39,785	)		7,716,731
	Segment income (loss)		¥	142,602		¥	(77,206	)	¥	170,006		¥	(4,038	)	¥	231,364	¥	—		¥	231,364
	Equity in income of affiliates		¥	31,185		¥	68,521		¥	—		¥	700		¥	100,406	¥	—		¥	100,406
	Segment assets		¥	1,006,684		¥	4,955,791		¥	5,644,380		¥	305,235		¥	11,912,090	¥	(124,491	)	¥	11,787,599
	Investments in affiliates		¥	70,275		¥	343,429		¥	—		¥	17,079		¥	430,783	¥	—		¥	430,783
	Depreciation and amortization		¥	43,564		¥	289,845		¥	211,325		¥	10,133		¥	554,867	¥	—		¥	554,867
	Capital expenditures		¥	62,075		¥	349,605		¥	686,495		¥	10,005		¥	1,108,180	¥	—		¥	1,108,180
	Damaged and impairment losses on long-lived assets		¥	—		¥	8,260		¥	1,514		¥	2,330		¥	12,104	¥	—		¥	12,104
	Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	13,032		¥	—		¥	13,032	¥	—		¥	13,032
	As of and for the year ended March 31, 2013
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
	External customers		¥	1,339,549		¥	7,709,216		¥	548,506		¥	280,676		¥	9,877,947	¥	—		¥	9,877,947
	Intersegment			—			14,374			11,750			10,994			37,118		(37,118	)		—
	Total		¥	1,339,549		¥	7,723,590		¥	560,256		¥	291,670		¥	9,915,065	¥	(37,118	)	¥	9,877,947
	Cost of sales, SG&A and R&D expenses			1,229,316			7,437,599			402,098			301,242			9,370,255		(37,118	)		9,333,137
	Segment income (loss)		¥	110,233		¥	285,991		¥	158,158		¥	(9,572	)	¥	544,810	¥	—		¥	544,810
	Equity in income of affiliates		¥	25,606		¥	56,361		¥	—		¥	756		¥	82,723	¥	—		¥	82,723
	Segment assets		¥	1,095,357		¥	5,759,126		¥	6,765,322		¥	309,149		¥	13,928,954	¥	(293,597	)	¥	13,635,357
	Investments in affiliates		¥	85,039		¥	352,317		¥	—		¥	20,020		¥	457,376	¥	—		¥	457,376
	Depreciation and amortization		¥	34,665		¥	290,522		¥	256,166		¥	9,116		¥	590,469	¥	—		¥	590,469
	Capital expenditures		¥	73,513		¥	540,625		¥	794,869		¥	14,519		¥	1,423,526	¥	—		¥	1,423,526
	Damaged and impairment losses on long-lived assets		¥	—		¥	—		¥	4,773		¥	—		¥	4,773	¥	—		¥	4,773
	Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	10,059		¥	—		¥	10,059	¥	—		¥	10,059
	As of and for the year ended March 31, 2014
			Yen (millions)
			Motorcycle			Automobile			Financial			Power			Segment		Reconciling			Consolidated
			Business			Business			Services			Product			Total		Items
									Business			and Other
												Businesses
	Net sales and other operating revenue:
	External customers		¥	1,663,631		¥	9,176,360		¥	698,185		¥	304,275		¥	11,842,451	¥	—		¥	11,842,451
	Intersegment			—			18,569			10,403			13,900			42,872		(42,872	)		—
	Total		¥	1,663,631		¥	9,194,929		¥	708,588		¥	318,175		¥	11,885,323	¥	(42,872	)	¥	11,842,451
	Cost of sales, SG&A and R&D expenses			1,498,026			8,791,228			525,832			319,956			11,135,042		(42,872	)		11,092,170
	Segment income (loss)		¥	165,605		¥	403,701		¥	182,756		¥	(1,781	)	¥	750,281	¥	—		¥	750,281
	Equity in income of affiliates		¥	36,479		¥	94,506		¥	—		¥	1,486		¥	132,471	¥	—		¥	132,471
	Segment assets		¥	1,264,903		¥	6,398,580		¥	7,980,989		¥	346,177		¥	15,990,649	¥	(368,618	)	¥	15,622,031
	Investments in affiliates		¥	102,359		¥	439,556		¥	—		¥	20,749		¥	562,664	¥	—		¥	562,664
	Depreciation and amortization		¥	46,038		¥	383,325		¥	354,704		¥	10,653		¥	794,720	¥	—		¥	794,720
	Capital expenditures		¥	57,702		¥	705,696		¥	1,131,761		¥	14,708		¥	1,909,867	¥	—		¥	1,909,867
	Damaged and impairment losses on long-lived assets		¥	—		¥	—		¥	3,301		¥	—		¥	3,301	¥	—		¥	3,301
	Provision for credit and lease residual losses on finance subsidiaries-receivables		¥	—		¥	—		¥	18,904		¥	—		¥	18,904	¥	—		¥	18,904
	Explanatory notes:
	1	Segment income (loss) of each segment is measured in a consistent manner with consolidated operating income, which is income before income taxes and equity in income of affiliates before other income (expenses). Expenses not directly associated with specific segments are allocated based on the most reasonable measures applicable.
	2	Segment assets of each segment are defined as total assets, including derivative financial instruments, investments in affiliates, and deferred tax assets. Segment assets are based on those directly associated with each segment and those not directly associated with specific segments are allocated based on the most reasonable measures applicable except for the corporate assets described below.
	3	Intersegment sales and revenues are generally made at values that approximate arm’s-length prices.
	4	Unallocated corporate assets, included in reconciling items, amounted to ¥399,732 million as of March 31, 2012, ¥293,583 million as of March 31, 2013 and ¥294,819 million as of March 31, 2014, respectively, which consist primarily of cash and cash equivalents, available-for-sale securities and held-to-maturity securities held by the Company. Reconciling items also include elimination of intersegment transactions.
5	Depreciation and amortization of Financial services business include ¥209,762 million for the year ended March 31, 2012, ¥254,933 million for the year ended March 31, 2013 and ¥352,402 million for the year ended March 31, 2014, respectively, of depreciation of property on operating leases.
6	Capital expenditures of Financial services business includes ¥683,767 million for the year ended March 31, 2012, ¥793,118 million for the year ended March 31, 2013 and ¥1,127,840 million for the year ended March 31, 2014, respectively, of purchases of operating lease assets.
7	Liabilities accrued for warranties issued are ¥60,004 million, ¥97,108 million and ¥153,898 million, for the years ended March 31, 2012, 2013 and 2014, respectively. These are mainly included in Cost of sales, SG&A and R&D expenses of Automobile business.
8	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. Effective April 1, 2012, Honda changed to the straight line method of depreciation. As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥6,358 million in Motorcycle business, ¥48,568 million in Automobile business, ¥77 million in Financial services business and ¥1,297 million in Power product and other businesses, respectively. It resulted in an increase of segment income, see note 1(k).
9	For the year ended March 31, 2012 and 2013, impacts of the floods in Thailand are mainly included in Cost of sales, SG&A and R&D expenses of Automobile business, see note 1(u).
External Sales and Other Operating Revenue by Product or Service Groups	'
	External Sales and Other Operating Revenue by Product or Service Groups
			Yen (millions)
			2012			2013			2014
	Motorcycles and relevant parts		¥	1,286,319		¥	1,274,890		¥	1,582,901
	All-terrain vehicles (ATVs) and relevant parts			62,509			64,659			80,730
	Automobiles and relevant parts			5,805,975			7,709,216			9,176,360
	Financial, insurance services			516,148			548,506			698,185
	Power products and relevant parts			208,661			221,321			251,630
	Others			68,483			59,355			52,645
	Total		¥	7,948,095		¥	9,877,947		¥	11,842,451
Geographical Information	'
	Geographical Information
	As of and for the year ended March 31, 2012
			Yen (millions)
			Japan			United			Other			Total
						States			Countries
	Net sales and other operating revenue		¥	1,774,573		¥	3,099,810		¥	3,073,712		¥	7,948,095
	Long-lived assets		¥	1,048,402		¥	1,889,567		¥	596,939		¥	3,534,908
	As of and for the year ended March 31, 2013
			Yen (millions)
			Japan			United			Other			Total
						States			Countries
	Net sales and other operating revenue		¥	1,925,333		¥	4,063,727		¥	3,888,887		¥	9,877,947
	Long-lived assets		¥	1,167,236		¥	2,380,885		¥	802,697		¥	4,350,818
	As of and for the year ended March 31, 2014
			Yen (millions)
			Japan			United			Other			Total
						States			Countries
	Net sales and other operating revenue		¥	2,216,735		¥	4,934,018		¥	4,691,698		¥	11,842,451
	Long-lived assets		¥	1,280,071		¥	2,783,977		¥	1,134,021		¥	5,198,069
Supplemental Geographical Information Based on Location of the Company and Its Subsidiaries	'
	Supplemental geographical information based on the location of the Company and its subsidiaries
	As of and for the year ended March 31, 2012
			Yen (millions)
			Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
						America									Regions					Items
	Net sales and other operating revenue:
	External customers		¥	1,774,573		¥	3,500,245		¥	519,329		¥	1,276,621		¥	877,327	¥	7,948,095		¥	—		¥	7,948,095
	Transfers between geographic areas			1,588,379			214,511			61,463			213,857			15,805		2,094,015			(2,094,015	)		—
	Total		¥	3,362,952		¥	3,714,756		¥	580,792		¥	1,490,478		¥	893,132	¥	10,042,110		¥	(2,094,015	)	¥	7,948,095
	Cost of sales, SG&A and R&D expenses		¥	3,472,786		¥	3,491,463		¥	592,901		¥	1,413,608		¥	836,176	¥	9,806,934		¥	(2,090,203	)	¥	7,716,731
	Operating income (loss)		¥	(109,834	)	¥	223,293		¥	(12,109	)	¥	76,870		¥	56,956	¥	235,176		¥	(3,812	)	¥	231,364
	Assets		¥	3,112,901		¥	6,333,851		¥	568,790		¥	1,070,331		¥	611,818	¥	11,697,691		¥	89,908		¥	11,787,599
	Long-lived assets		¥	1,048,402		¥	1,970,631		¥	111,354		¥	274,182		¥	130,339	¥	3,534,908		¥	—		¥	3,534,908
	As of and for the year ended March 31, 2013
			Yen (millions)
			Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
						America									Regions					Items
	Net sales and other operating revenue:
	External customers		¥	1,925,333		¥	4,612,361		¥	536,856		¥	1,926,434		¥	876,963	¥	9,877,947		¥	—		¥	9,877,947
	Transfers between geographic areas			1,968,179			244,741			105,254			379,213			19,504		2,716,891			(2,716,891	)		—
	Total		¥	3,893,512		¥	4,857,102		¥	642,110		¥	2,305,647		¥	896,467	¥	12,594,838		¥	(2,716,891	)	¥	9,877,947
	Cost of sales, SG&A and R&D expenses		¥	3,715,084		¥	4,648,184		¥	641,650		¥	2,158,889		¥	860,773	¥	12,024,580		¥	(2,691,443	)	¥	9,333,137
	Operating income (loss)		¥	178,428		¥	208,918		¥	460		¥	146,758		¥	35,694	¥	570,258		¥	(25,448	)	¥	544,810
	Assets		¥	3,264,383		¥	7,645,540		¥	673,667		¥	1,523,192		¥	660,856	¥	13,767,638		¥	(132,281	)	¥	13,635,357
	Long-lived assets		¥	1,167,236		¥	2,481,097		¥	124,088		¥	434,827		¥	143,570	¥	4,350,818		¥	—		¥	4,350,818
	As of and for the year ended March 31, 2014
			Yen (millions)
			Japan			North			Europe			Asia			Other		Total			Reconciling			Consolidated
						America									Regions					Items
	Net sales and other operating revenue:
	External customers		¥	2,216,735		¥	5,595,981		¥	676,502		¥	2,340,100		¥	1,013,133	¥	11,842,451		¥	—		¥	11,842,451
	Transfers between geographic areas			1,975,544			374,018			98,766			486,823			12,368		2,947,519			(2,947,519	)		—
	Total		¥	4,192,279		¥	5,969,999		¥	775,268		¥	2,826,923		¥	1,025,501	¥	14,789,970		¥	(2,947,519	)	¥	11,842,451
	Cost of sales, SG&A and R&D expenses		¥	3,978,185		¥	5,679,094		¥	792,393		¥	2,609,023		¥	980,600	¥	14,039,295		¥	(2,947,125	)	¥	11,092,170
	Operating income (loss)		¥	214,094		¥	290,905		¥	(17,125	)	¥	217,900		¥	44,901	¥	750,675		¥	(394	)	¥	750,281
	Assets		¥	3,442,746		¥	8,825,278		¥	709,469		¥	1,996,929		¥	767,225	¥	15,741,647		¥	(119,616	)	¥	15,622,031
	Long-lived assets		¥	1,280,071		¥	3,025,095		¥	133,061		¥	588,413		¥	171,429	¥	5,198,069		¥	—		¥	5,198,069
	Explanatory notes:
	1	Major countries or regions in each geographic area:
	North America		United States, Canada, Mexico
	Europe		United Kingdom, Germany, France, Belgium, Russia
	Asia		Thailand, Indonesia, China, India, Vietnam
	Other Regions		Brazil, Australia
	2	Operating income (loss) of each geographical region is measured in a consistent manner with consolidated operating income, which is income before income taxes and equity in income of affiliates before other income (expenses).
	3	Assets of each geographical region are defined as total assets, including derivative financial instruments, investments in affiliates, and deferred tax assets.
	4	Sales and revenues between geographic areas are generally made at values that approximate arm’s-length prices.
	5	Unallocated corporate assets, included in reconciling items, amounted to ¥399,732 million as of March 31, 2012, ¥293,583 million as of March 31, 2013 and ¥294,819 million as of March 31, 2014, respectively, which consist primarily of cash and cash equivalents, available-for-sale securities and held-to-maturity securities held by the Company. Reconciling items also include elimination of transactions between geographic areas.
	6	Previously, Honda used principally the declining-balance method for calculating the depreciation of property, plant and equipment. Effective April 1, 2012, Honda changed to the straight line method of depreciation. As a result of the change in depreciation method, depreciation expense for the year ended March 31, 2013 decreased by approximately ¥42,486 million in Japan, ¥9,602 million in North America, ¥1,068 million in Europe and ¥3,144 million in Asia, respectively. It resulted in an increase of operating income, see note 1(k).
	7	For the year ended March 31, 2012 and 2013, impacts of the floods in Thailand are included in Cost of sales, SG&A and R&D expenses of Asia, see note 1(u).

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Mar. 31, 2014
Quarterly Financial Data	'
	Quarterly financial data for the years ended March 31, 2012, 2013 and 2014 are set forth in the following table:
			Yen (millions)						Yen
			Net sales and other		Operating		Net income (loss)		Basic net income (loss)
			operating revenue		Income (loss)		attributable to		attributable to
							Honda Motor Co., Ltd.		Honda Motor Co., Ltd.
									per common share
	Year ended March 31, 2012:
	First quarter		¥	1,714,596	¥	22,579	¥	31,797	¥	17.64
	Second quarter			1,885,892		52,511		60,429		33.53
	Third quarter			1,942,545		44,298		47,662		26.45
	Fourth quarter			2,405,062		111,976		71,594		39.72
			¥	7,948,095	¥	231,364	¥	211,482	¥	117.34
	Year ended March 31, 2013:
	First quarter		¥	2,435,909	¥	176,013	¥	131,723	¥	73.09
	Second quarter			2,271,286		100,867		82,233		45.63
	Third quarter			2,425,792		131,941		77,441		42.97
	Fourth quarter			2,744,960		135,989		75,752		42.03
			¥	9,877,947	¥	544,810	¥	367,149	¥	203.71
	Year ended March 31, 2014:
	First quarter		¥	2,834,095	¥	184,963	¥	122,499	¥	67.97
	Second quarter			2,890,221		171,451		120,368		66.79
	Third quarter			3,020,889		228,574		160,732		89.18
	Fourth quarter			3,097,246		165,293		170,508		94.61
			¥	11,842,451	¥	750,281	¥	574,107	¥	318.54
	*	All quarterly financial data is unaudited and also has not been reviewed by the independent registered public accounting firm.

General_and_Summary_of_Signifi3

General and Summary of Significant Accounting Policies - Additional Information (Detail) (JPY ¥)

3 Months Ended

12 Months Ended

In Millions, except Share data, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2012

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2013

Mar. 31, 2011

Flood

Flood

Flood

Flood

Flood

Change in depreciation method

Adjustment resulting from change in fiscal year-end of a subsidiary

Losses on damaged inventories

Loss on damaged property, plant and equipment

Selling, general and administrative expenses

Selling, general and administrative expenses

Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Retained earnings increased (decreased)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

¥ 6,023

Noncontrolling interests increased (decreased)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,658

Goodwill, impairment loss

'

'

'

'

'

'

'

'

'

'

'

'

0

0

0

'

'

'

'

'

'

'

Carrying amount of goodwill

11,439

'

'

'

10,296

'

'

'

'

'

'

'

11,439

10,296

'

'

'

'

'

'

'

'

Depreciation expense decreased (increased)

'

'

'

'

'

'

'

'

'

'

'

'

-442,318

-335,536

-345,105

'

'

'

'

'

56,300

'

Net income attributable to Honda Motor Co., Ltd. increased (decreased)

170,508

160,732

120,368

122,499

75,752

77,441

82,233

131,723

71,594

47,662

60,429

31,797

574,107

367,149

211,482

'

'

'

'

'

35,746

'

Basic net income attributable to Honda Motor Co., Ltd. per common share increased (decreased) (in yen per share)

¥ 94.61

¥ 89.18

¥ 66.79

¥ 67.97

¥ 42.03

¥ 42.97

¥ 45.63

¥ 73.09

¥ 39.72

¥ 26.45

¥ 33.53

¥ 17.64

¥ 318.54

¥ 203.71

¥ 117.34

'

'

'

'

'

¥ 19.83

'

Advertising expenses

'

'

'

'

'

'

'

'

'

'

'

'

297,514

254,016

195,284

'

'

'

'

'

'

'

Weighted average number of common shares outstanding (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

1,802,294,383

1,802,298,819

1,802,300,720

'

'

'

'

'

'

'

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

11,092,170

9,333,137

7,716,731

23,420

'

'

'

'

'

'

Cost of sales

'

'

'

'

'

'

'

'

'

'

'

'

8,761,083

7,345,162

5,919,633

10,680

7,330

'

'

'

'

'

Selling, general and administrative expenses

'

'

'

'

'

'

'

'

'

'

'

'

1,696,957

1,427,705

1,277,280

12,740

'

7,654

'

'

'

'

Insurance recoveries included in selling, general and administrative expenses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

¥ 16,278

¥ 21,725

'

'

Estimated_Useful_Lives_Used_in

Estimated Useful Lives Used in Computing Depreciation and Amortization of Property, Plant and Equipment (Detail)	12 Months Ended
	Mar. 31, 2014
Minimum | Buildings and structures	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives used in computing depreciation and amortization of property, plant and equipment	'3 years
Minimum | Machinery and equipment	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives used in computing depreciation and amortization of property, plant and equipment	'2 years
Maximum | Buildings and structures	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives used in computing depreciation and amortization of property, plant and equipment	'50 years
Maximum | Machinery and equipment	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives used in computing depreciation and amortization of property, plant and equipment	'20 years

Foreign_Currency_Translation_a

Foreign Currency Translation and Transaction Net Gains or Losses (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Intercompany Foreign Currency Balance [Line Items]	'	'	'
Foreign currency translation and transaction gains (losses) included in other income (expenses)-other, net	¥ (6,461)	¥ 36,794	¥ 4,563

Shipping_and_Handling_Costs_De

Shipping and Handling Costs (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Component of Operating Other Cost and Expense [Line Items]	'	'	'
Shipping and handling costs included in selling, general and administrative expenses	¥ 180,554	¥ 160,843	¥ 155,276

Finance_Income_and_Related_Cos2

Finance Income and Related Costs of Finance Subsidiaries (Detail) (Finance subsidiaries, JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Finance subsidiaries	'	'	'
Finance Income and Related Cost of Finance Subsidiaries [Line Items]	'	'	'
Finance income	¥ 708,588	¥ 560,256	¥ 526,576
Finance costs	¥ 440,148	¥ 336,203	¥ 293,216

Finance_Subsidiariesreceivable

Finance Subsidiaries-receivables, Net (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	¥ 5,599,072	¥ 4,746,097	'
Less:	'	'	'
Allowance for credit losses	24,851	19,716	23,049
Allowance for losses on lease residual values	2,131	3,354	'
Unearned interest income and fees	38,093	18,697	'
Finance receivables, net	5,533,997	4,704,330	'
Finance subsidiaries-receivables, net	4,781,768	4,031,137	'
Less current portion	1,464,215	1,243,002	'
Noncurrent finance subsidiaries-receivables, net	3,317,553	2,788,135	'
Trade accounts and notes receivables, net	'	'	'
Less:	'	'	'
Finance receivables, net	498,230	461,450	'
Other assets, net	'	'	'
Less:	'	'	'
Finance receivables, net	253,999	211,743	'
Retail	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	4,678,741	3,865,430	'
Less:	'	'	'
Allowance for credit losses	21,637	17,643	20,497
Direct financing lease	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	422,936	448,672	'
Less:	'	'	'
Allowance for credit losses	636	789	1,151
Wholesale	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	497,395	431,995	'
Less:	'	'	'
Allowance for credit losses	2,578	1,284	1,401
Wholesale flooring	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	434,219	389,562	'
Commercial loans	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Finance receivables	¥ 63,176	¥ 42,433	'

Changes_in_Allowance_for_Credi

Changes in Allowance for Credit Losses on Finance Receivables (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Balance at beginning of year	¥ 19,716	¥ 23,049
Provision	20,410	9,158
Charge-offs	-28,548	-22,067
Recoveries	11,780	8,276
Adjustments from foreign currency translation	1,493	1,300
Balance at end of year	24,851	19,716
Retail	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Balance at beginning of year	17,643	20,497
Provision	18,616	8,707
Charge-offs	-27,550	-20,838
Recoveries	11,676	8,143
Adjustments from foreign currency translation	1,252	1,134
Balance at end of year	21,637	17,643
Direct financing lease	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Balance at beginning of year	789	1,151
Provision	310	392
Charge-offs	-573	-940
Recoveries	93	117
Adjustments from foreign currency translation	17	69
Balance at end of year	636	789
Wholesale	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Balance at beginning of year	1,284	1,401
Provision	1,484	59
Charge-offs	-425	-289
Recoveries	11	16
Adjustments from foreign currency translation	224	97
Balance at end of year	¥ 2,578	¥ 1,284

Age_Analysis_of_Past_Due_Finan

Age Analysis of Past Due Finance Receivables (Detail) (JPY ¥)	Mar. 31, 2014		Mar. 31, 2013
In Millions, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	¥ 24,376		¥ 20,395
60-89 days past due	3,706		3,095
90 days and greater past due	6,101		6,191
Total past due	34,183		29,681
Current	5,564,889	[1]	4,716,416	[1]
Total finance receivables	5,599,072		4,746,097
Retail	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	22,744		19,224
60-89 days past due	3,265		2,867
90 days and greater past due	4,826		4,236
Total past due	30,835		26,327
Current	4,647,906	[1]	3,839,103	[1]
Total finance receivables	4,678,741		3,865,430
New auto	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	15,948		12,947
60-89 days past due	2,069		1,805
90 days and greater past due	2,745		2,607
Total past due	20,762		17,359
Current	4,044,290	[1]	3,247,241	[1]
Total finance receivables	4,065,052		3,264,600
Used and certified auto	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	5,557		5,064
60-89 days past due	689		643
90 days and greater past due	281		276
Total past due	6,527		5,983
Current	424,872	[1]	434,183	[1]
Total finance receivables	431,399		440,166
Others	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	1,239		1,213
60-89 days past due	507		419
90 days and greater past due	1,800		1,353
Total past due	3,546		2,985
Current	178,744	[1]	157,679	[1]
Total finance receivables	182,290		160,664
Direct financing lease	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	1,106		966
60-89 days past due	214		161
90 days and greater past due	384		1,644
Total past due	1,704		2,771
Current	421,232	[1]	445,901	[1]
Total finance receivables	422,936		448,672
Wholesale	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	526		205
60-89 days past due	227		67
90 days and greater past due	891		311
Total past due	1,644		583
Current	495,751	[1]	431,412	[1]
Total finance receivables	497,395		431,995
Wholesale flooring	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 days past due	526		205
60-89 days past due	227		67
90 days and greater past due	758		311
Total past due	1,511		583
Current	432,708	[1]	388,979	[1]
Total finance receivables	434,219		389,562
Commercial loans	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
90 days and greater past due	133		'
Total past due	133		'
Current	63,043	[1]	42,433	[1]
Total finance receivables	¥ 63,176		¥ 42,433
[1]	Includes recorded investment of finance receivables that are less than 30 days past due.

Finance_Receivables_by_Credit_

Finance Receivables by Credit Quality Indicator (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	¥ 5,599,072	¥ 4,746,097
Total	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	5,101,677	4,314,102
Total | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	5,092,988	4,305,194
Total | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	8,689	8,908
Retail	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	4,678,741	3,865,430
Retail | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	4,670,650	3,858,327
Retail | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	8,091	7,103
New auto	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	4,065,052	3,264,600
New auto | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	4,060,238	3,260,188
New auto | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	4,814	4,412
Used and certified auto	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	431,399	440,166
Used and certified auto | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	430,429	439,247
Used and certified auto | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	970	919
Others	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	182,290	160,664
Others | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	179,983	158,892
Others | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	2,307	1,772
Direct financing lease	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	422,936	448,672
Direct financing lease | Performing	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	422,338	446,867
Direct financing lease | Nonperforming	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	598	1,805
Wholesale	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	497,395	431,995
Wholesale | Group A	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	281,383	260,401
Wholesale | Group B	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	216,012	171,594
Wholesale flooring	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	434,219	389,562
Wholesale flooring | Group A	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	245,019	236,203
Wholesale flooring | Group B	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	189,200	153,359
Commercial loans	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	63,176	42,433
Commercial loans | Group A	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	36,364	24,198
Commercial loans | Group B	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Finance receivables	¥ 26,812	¥ 18,235

Contractual_Maturities_of_Fina

Contractual Maturities of Finance Receivables (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Investments Classified by Contractual Maturity Date [Line Items]	'	'
2015	¥ 1,992,551	'
2016	1,425,249	'
2017	1,020,626	'
2018	685,494	'
2019	356,586	'
After five years	118,566	'
Finance receivables, noncurrent	3,606,521	'
Total finance receivables	¥ 5,599,072	¥ 4,746,097

Finance_Receivables_Additional

Finance Receivables - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Other finance receivables	¥ 29,605	¥ 37,274
Other finance receivables, impaired	20,094	19,562
Other finance receivables, allowance for credit losses	¥ 19,996	¥ 19,541

Assets_and_Liabilities_of_Cons

Assets and Liabilities of Consolidated VIEs (Detail) (JPY ¥)	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
In Millions, unless otherwise specified
Variable Interest Entity [Line Items]	'		'		'
Finance subsidiaries-receivables, net	¥ 4,781,768		¥ 4,031,137		'
Total assets	15,622,031		13,635,357		11,787,599
Total liabilities	9,508,633		8,429,934		'
Consolidated variable interest entities	'		'		'
Variable Interest Entity [Line Items]	'		'		'
Finance subsidiaries-receivables, net	872,621		713,631		'
Restricted cash	27,468	[1]	20,885	[1]	'
Other assets	1,462		1,545		'
Total assets	901,551		736,061		'
Secured debt	877,054	[2]	718,980	[2]	'
Other liabilities	249		237		'
Total liabilities	¥ 877,303		¥ 719,217		'
[1]	Restricted cash as collateral for the payment of the related secured debt obligation is included in other current assets and investment and advances-other on the consolidated balance sheets.
[2]	Secured debt is included in short-term, current portion of long-term and long-term debt on the consolidated balance sheets.

Inventories_Detail

Inventories (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Inventory [Line Items]	'	'
Finished goods	¥ 759,099	¥ 726,034
Work in process	69,731	53,035
Raw materials	474,065	436,352
Total	¥ 1,302,895	¥ 1,215,421

Equity_Securities_which_Have_Q

Equity Securities which Have Quoted Market Values, Included in Investments in Affiliates (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Investments in and Advances to Affiliates [Line Items]	'	'
Carrying amounts	¥ 212,615	¥ 175,420
Market values	¥ 242,671	¥ 220,221

Combined_Financial_Information

Combined Financial Information in Respect of Affiliates Accounted for under Equity Method (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Schedule of Equity Method Investments [Line Items]	'	'	'
Current assets	¥ 2,017,359	¥ 1,588,871	'
Other assets, principally property, plant and equipment	1,369,651	1,299,774	'
Total assets	3,387,010	2,888,645	'
Current liabilities	1,515,407	1,170,956	'
Other liabilities	242,643	255,248	'
Total liabilities	1,758,050	1,426,204	'
Equity	1,628,960	1,462,441	'
Net sales	5,413,219	4,794,027	4,491,867
Net income attributable to Honda's affiliates	312,486	224,340	250,993
Motorcycle Business	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Current assets	258,565	228,358	'
Other assets, principally property, plant and equipment	126,888	134,901	'
Total assets	385,453	363,259	'
Current liabilities	168,060	149,033	'
Other liabilities	12,849	10,075	'
Total liabilities	180,909	159,108	'
Equity	204,544	204,151	'
Net sales	1,070,837	891,343	888,914
Net income attributable to Honda's affiliates	79,381	60,586	72,168
Automobile Business	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Current assets	1,732,609	1,335,075	'
Other assets, principally property, plant and equipment	1,212,313	1,137,654	'
Total assets	2,944,922	2,472,729	'
Current liabilities	1,337,236	1,013,565	'
Other liabilities	226,822	242,194	'
Total liabilities	1,564,058	1,255,759	'
Equity	1,380,864	1,216,970	'
Net sales	4,314,804	3,876,766	3,579,019
Net income attributable to Honda's affiliates	230,397	162,037	177,309
Power Product and Other Businesses	'	'	'
Schedule of Equity Method Investments [Line Items]	'	'	'
Current assets	26,185	25,438	'
Other assets, principally property, plant and equipment	30,450	27,219	'
Total assets	56,635	52,657	'
Current liabilities	10,111	8,358	'
Other liabilities	2,972	2,979	'
Total liabilities	13,083	11,337	'
Equity	43,552	41,320	'
Net sales	27,578	25,918	23,934
Net income attributable to Honda's affiliates	¥ 2,708	¥ 1,717	¥ 1,516

Significant_Investments_in_Aff

Significant Investments in Affiliates Accounted for under Equity Method (Detail)	Mar. 31, 2014	Mar. 31, 2013
Motorcycle Business | P.T. Astra Honda Motor	'	'
Schedule of Equity Method Investments [Line Items]	'	'
Percentage ownership	50.00%	50.00%
Automobile Business | Guangqi Honda Automobile Co., Ltd.	'	'
Schedule of Equity Method Investments [Line Items]	'	'
Percentage ownership	50.00%	50.00%
Automobile Business | Dongfeng Honda Automobile Co., Ltd.	'	'
Schedule of Equity Method Investments [Line Items]	'	'
Percentage ownership	50.00%	50.00%
Automobile Business | Dongfeng Honda Engine Co., Ltd.	'	'
Schedule of Equity Method Investments [Line Items]	'	'
Percentage ownership	50.00%	50.00%

Investments_in_and_Advances_to2

Investments in and Advances to Affiliates - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2013
In Millions, unless otherwise specified			Equity in income of affiliates
Schedule of Equity Method Investments [Line Items]	'	'	'
Impairment losses on certain investments in affiliates, net of tax	'	'	¥ 12,757
Honda's equity in undistributed income of affiliates	¥ 417,050	¥ 376,888	'

Transactions_with_Affiliates_D

Transactions with Affiliates (Detail) (Affiliates, JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Affiliates	'	'	'
Related Party Transaction [Line Items]	'	'	'
Amounts due from	¥ 225,383	¥ 160,470	'
Amounts due to	138,181	97,958	'
Purchases from	1,028,523	789,261	762,415
Sales to	¥ 786,802	¥ 636,299	¥ 561,426

Investments_and_AdvancesOther_1

Investments and Advances-Other, Current (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	¥ 37,268	¥ 14,875
Corporate debt securities	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	11,050	1,553
Government bonds	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	2,000	'
Local bonds	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	6,620	'
Advances	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	1,028	926
Certificates of deposit	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	1,558	1,550
Other	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, current	¥ 15,012	¥ 10,846

Investments_and_AdvancesOther_2

Investments and Advances-Other, Noncurrent (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	¥ 253,661	¥ 209,680
Auction rate securities	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	6,999	6,928
Marketable equity securities	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	138,476	117,110
Corporate debt securities	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	8,542	1,505
Government bonds	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	'	2,000
Local bonds	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	15,850	9,499
U.S. government agency debt securities	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	5,455	1,068
Non-marketable preferred stocks	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	969	969
Other	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	10,316	10,780
Guaranty deposits	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	18,742	20,210
Advances	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	1,998	2,132
Other	'	'
Investments and Advances [Line Items]	'	'
Investments and advances - other, noncurrent	¥ 46,314	¥ 37,479

Availableforsale_Securities_an

Available-for-sale Securities and Held-to-maturity Securities (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Available-for-sale	'	'
Cost	¥ 84,820	¥ 49,990
Fair value	185,960	128,848
Gross unrealized gains	101,917	80,453
Gross unrealized losses	777	1,595
Held-to-maturity	'	'
Amortized cost	34,650	16,511
Fair value	34,667	16,556
Gross unrealized gains	17	45
Gross unrealized losses	'	'

Maturities_of_Debt_Securities_

Maturities of Debt Securities Classified as Available-for-sale (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'
Due within one year	¥ 2,676
Due after one year through five years	12,968
Due after five years through ten years	8,748
Due after ten years	14,512
Total	¥ 38,904

Maturities_of_Debt_Securities_1

Maturities of Debt Securities Classified as Held-to-maturity (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Schedule of Held-to-maturity Securities [Line Items]	'	'
Due within one year	¥ 22,378	'
Due after one year through five years	476	'
Due after five years through ten years	10,954	'
Due after ten years	842	'
Total	¥ 34,650	¥ 16,511

Gross_Unrealized_Losses_on_Ava

Gross Unrealized Losses on Available-for-sale Securities (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014
Available-for-sale, fair value	'
Less than 12 months, fair value	¥ 8,877
12 months or longer, fair value	7,351
Total	16,228
Available-for-sale, unrealized losses	'
Less than 12 months, unrealized losses	224
12 months or longer, unrealized losses	553
Total	¥ 777

Investments_and_AdvancesOther_3

Investments and Advances-Other - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Investments and Advances [Line Items]	'
Held-to-maturity securities in a loss position	¥ 0

Future_Minimum_Lease_Rentals_E

Future Minimum Lease Rentals Expected to Be Received from Property on Operating Leases (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Years ending March 31	'
2015	¥ 380,146
2016	247,759
2017	89,967
2018	9,148
2019	2,058
Total future minimum lease rentals	¥ 729,078

Shortterm_Debt_Detail

Short-term Debt (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Short-term Debt [Line Items]	'	'
Short-term bank loans	¥ 373,610	¥ 347,842
Asset-backed notes	69,032	37,448
Medium-term notes	231,519	159,963
Commercial paper	645,183	693,044
Total	¥ 1,319,344	¥ 1,238,297

Shortterm_and_Longterm_Debt_Ad

Short-term and Long-term Debt - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Debt Disclosure [Line Items]	'	'
Weighted average interest rates on short-term debt outstanding (in percentage)	1.15%	0.86%
Weighted average interest rates on total outstanding long-term debt (in percentage)	1.71%	1.82%
Unused line of credit facilities related to commercial paper programs and medium-term notes programs	¥ 2,718,969	'
Committed lines of unused credit	1,024,274	'
Unused committed lines supporting commercial paper programs	965,066	'
Loans | Minimum	'	'
Debt Disclosure [Line Items]	'	'
Interest rates on long-term debt (in percentage)	0.45%	'
Loans | Maximum	'	'
Debt Disclosure [Line Items]	'	'
Interest rates on long-term debt (in percentage)	12.50%	'
Asset-backed notes	'	'
Debt Disclosure [Line Items]	'	'
Weighted average interest rates on secured debt (in percentage)	0.70%	0.89%
Medium-term notes	'	'
Debt Disclosure [Line Items]	'	'
Unused line of credit facilities related to commercial paper programs and medium-term notes programs	1,991,166	'
Medium-term notes | Minimum	'	'
Debt Disclosure [Line Items]	'	'
Interest rates on unsecured debt (in percentage)	0.22%	0.38%
Medium-term notes | Maximum	'	'
Debt Disclosure [Line Items]	'	'
Interest rates on unsecured debt (in percentage)	7.63%	5.03%
Commercial paper	'	'
Debt Disclosure [Line Items]	'	'
Unused line of credit facilities related to commercial paper programs and medium-term notes programs	¥ 727,803	'

Longterm_Debt_Detail

Long-term Debt (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
Total long-term debt	¥ 4,537,530	¥ 3,655,891
Less current portion	1,303,464	945,046
Total long-term debt, excluding current portion	3,234,066	2,710,845
Honda Motor Co., Ltd.	'	'
Debt Instrument [Line Items]	'	'
Total long-term debt	128	160
Honda Motor Co., Ltd. | Loans, maturing through 2031, principally from banks	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	128	160
Subsidiaries	'	'
Debt Instrument [Line Items]	'	'
Less unamortized discount, net	7,001	5,927
Total long-term debt	4,537,402	3,655,731
Subsidiaries | Loans, maturing through 2029, principally from banks	'	'
Debt Instrument [Line Items]	'	'
Secured debt	30,466	15,830
Unsecured debt	1,224,947	1,043,857
Subsidiaries | Asset-backed notes, maturing through 2019	'	'
Debt Instrument [Line Items]	'	'
Secured debt	808,022	681,020
Subsidiaries | 1.31% Japanese yen unsecured bond due 2013	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	'	40,000
Subsidiaries | 1.05% Japanese yen unsecured bond due 2014	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	30,000	30,000
Subsidiaries | 0.56% Japanese yen unsecured bond due 2015	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	30,000	30,000
Subsidiaries | 0.59% Japanese yen unsecured bond due 2015	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	30,000	30,000
Subsidiaries | 0.47% Japanese yen unsecured bond due 2016	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	40,000	40,000
Subsidiaries | 0.48% Japanese yen unsecured bond due 2017	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	40,000	40,000
Subsidiaries | 0.37% Japanese yen unsecured bond due 2017	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	30,000	30,000
Subsidiaries | 0.35% Japanese yen unsecured bond due 2017	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	35,000	35,000
Subsidiaries | 0.27% Japanese yen unsecured bond due 2018	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	30,000	30,000
Subsidiaries | 0.55% Japanese yen unsecured bond due 2018	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	50,000	'
Subsidiaries | 0.32% Japanese yen unsecured bond due 2018	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	40,000	'
Subsidiaries | 0.25% Japanese yen unsecured bond due 2019	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	40,000	'
Subsidiaries | 0.59% Japanese yen unsecured bond due 2019	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	10,000	10,000
Subsidiaries | 0.56% Japanese yen unsecured bond due 2019	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	15,000	15,000
Subsidiaries | 0.55% Japanese yen unsecured bond due 2020	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	10,000	10,000
Subsidiaries | 0.49% Japanese yen unsecured bond due 2020	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	10,000	'
Subsidiaries | 0.43% Japanese yen unsecured bond due 2021	'	'
Debt Instrument [Line Items]	'	'
Unsecured debt	10,000	'
Subsidiaries | Medium-term notes, maturing through 2023	'	'
Debt Instrument [Line Items]	'	'
Medium-term notes	¥ 2,030,968	¥ 1,580,951

Longterm_Debt_Parenthetical_De

Long-term Debt (Parenthetical) (Detail) (Subsidiaries)	Mar. 31, 2014
1.31% Japanese yen unsecured bond due 2013	'
Debt Instrument [Line Items]	'
Interest rate	1.31%
1.05% Japanese yen unsecured bond due 2014	'
Debt Instrument [Line Items]	'
Interest rate	1.05%
0.56% Japanese yen unsecured bond due 2015	'
Debt Instrument [Line Items]	'
Interest rate	0.56%
0.59% Japanese yen unsecured bond due 2015	'
Debt Instrument [Line Items]	'
Interest rate	0.59%
0.47% Japanese yen unsecured bond due 2016	'
Debt Instrument [Line Items]	'
Interest rate	0.47%
0.48% Japanese yen unsecured bond due 2017	'
Debt Instrument [Line Items]	'
Interest rate	0.48%
0.37% Japanese yen unsecured bond due 2017	'
Debt Instrument [Line Items]	'
Interest rate	0.37%
0.35% Japanese yen unsecured bond due 2017	'
Debt Instrument [Line Items]	'
Interest rate	0.35%
0.27% Japanese yen unsecured bond due 2018	'
Debt Instrument [Line Items]	'
Interest rate	0.27%
0.55% Japanese yen unsecured bond due 2018	'
Debt Instrument [Line Items]	'
Interest rate	0.55%
0.32% Japanese yen unsecured bond due 2018	'
Debt Instrument [Line Items]	'
Interest rate	0.32%
0.25% Japanese yen unsecured bond due 2019	'
Debt Instrument [Line Items]	'
Interest rate	0.25%
0.59% Japanese yen unsecured bond due 2019	'
Debt Instrument [Line Items]	'
Interest rate	0.59%
0.56% Japanese yen unsecured bond due 2019	'
Debt Instrument [Line Items]	'
Interest rate	0.56%
0.55% Japanese yen unsecured bond due 2020	'
Debt Instrument [Line Items]	'
Interest rate	0.55%
0.49% Japanese yen unsecured bond due 2020	'
Debt Instrument [Line Items]	'
Interest rate	0.49%
0.43% Japanese yen unsecured bond due 2021	'
Debt Instrument [Line Items]	'
Interest rate	0.43%

Pledged_Assets_Detail

Pledged Assets (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Debt Disclosure [Line Items]	'	'
Trade accounts and notes receivable	¥ 31,318	¥ 25,528
Inventories	12,908	11,154
Property, plant and equipment	58,504	26,169
Finance subsidiaries-receivables	¥ 883,776	¥ 724,399

Maturities_of_Longterm_Debt_De

Maturities of Long-term Debt (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Long Term-debt Maturities Repayments of Principal [Line Items]	'	'
2015	¥ 1,303,464	'
2016	963,462	'
2017	1,125,196	'
2018	391,004	'
2019	460,730	'
After five years	293,674	'
Long-term debt, noncurrent	3,234,066	2,710,845
Total	¥ 4,537,530	¥ 3,655,891

Other_Liabilities_Detail

Other Liabilities (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Other Liabilities [Line Items]	'	'
Accrued liabilities for product warranty, excluding current portion	¥ 114,927	¥ 104,584
Pension and other postretirement benefits	445,350	622,462
Deferred income taxes	706,662	615,879
Other	296,299	287,160
Total	¥ 1,563,238	¥ 1,630,085

Total_Income_Tax_Expense_Benef

Total Income Tax Expense (Benefit) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Income Taxes [Line Items]	'	'	'
Income from continuing operations	¥ 252,662	¥ 178,976	¥ 135,735
Other comprehensive income (loss) (note 15)	72,486	252	-20,701
Total	¥ 325,148	¥ 179,228	¥ 115,034

Income_Loss_before_Income_Taxe

Income (Loss) before Income Taxes and Equity in Income of Affiliates by Japanese and Foreign Source (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Income (loss) before income taxes and equity in income of affiliates	¥ 728,940	¥ 488,891	¥ 257,403
Japanese	'	'	'
Income (loss) before income taxes and equity in income of affiliates	214,698	50,450	-125,787
Foreign	'	'	'
Income (loss) before income taxes and equity in income of affiliates	¥ 514,242	¥ 438,441	¥ 383,190

Income_Tax_Expense_Benefit_Det

Income Tax Expense (Benefit) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Income Taxes [Line Items]	'	'	'
Current	¥ 207,236	¥ 125,724	¥ 86,074
Deferred	45,426	53,252	49,661
Total	252,662	178,976	135,735
Japanese	'	'	'
Income Taxes [Line Items]	'	'	'
Current	-794	-3,666	8,136
Deferred	54,622	21,977	-26,071
Total	53,828	18,311	-17,935
Foreign	'	'	'
Income Taxes [Line Items]	'	'	'
Current	208,030	129,390	77,938
Deferred	-9,196	31,275	75,732
Total	¥ 198,834	¥ 160,665	¥ 153,670

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income Taxes [Line Items]	'	'	'	'
Statutory income tax rate (in percentage)	37.90%	37.90%	40.00%	'
Net change in the total valuation allowance increased (decreased)	¥ 16,131	¥ 11,915	¥ 3,613	'
Operating loss carryforwards	353,357	'	'	'
Tax credit carryforwards	34,578	'	'	'
Deferred tax liabilities not recognized for undistributed earnings of the Company's foreign subsidiaries and foreign corporate joint ventures	195,476	140,691	'	'
Undistributed earnings not subject to deferred tax liabilities	4,284,270	4,133,175	'	'
Unrecognized tax benefits	6,983	39,151	43,627	46,265
Unrecognized tax benefits that would impact Honda's effective income tax rate, if recognized	5,362	37,012	32,460	'
Recognized interest and penalties, net included in income tax expense	-2,406	764	-513	'
Accrued interest and accrued penalties	¥ 1,235	¥ 3,292	'	'
Open tax years under income tax examination	'Honda has open tax years primarily from 2005 to 2014 with various significant tax jurisdictions including Japan (fiscal years 2008-2014), the United States (fiscal years 2005-2014), Canada, the United Kingdom, Germany, France, Belgium, Thailand, India, Brazil and Australia.	'	'	'
Japanese	'	'	'	'
Income Taxes [Line Items]	'	'	'	'
Statutory income tax rate (in percentage)	37.90%	37.90%	40.00%	'
Foreign | Minimum	'	'	'	'
Income Taxes [Line Items]	'	'	'	'
Statutory income tax rate (in percentage)	16.00%	'	'	'
Foreign | Maximum	'	'	'	'
Income Taxes [Line Items]	'	'	'	'
Statutory income tax rate (in percentage)	38.00%	'	'	'

Effective_Income_Tax_Rate_Deta

Effective Income Tax Rate (Detail)	12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Reconciliation of Statutory Federal Tax Rate [Line Items]	'		'		'
Statutory income tax rate	37.90%		37.90%		40.00%
Recognition of valuation allowance	2.30%		2.20%		7.20%
Difference in statutory tax rates of foreign subsidiaries	-8.10%		-6.70%		-12.20%
Reversal of valuation allowance	-0.80%		-1.50%		-1.80%
Research and development credit	-0.90%		-0.70%		-0.60%
Dividend and royalty income from subsidiaries and affiliates, net of foreign tax credit	4.70%		4.40%		9.80%
Undistributed earnings of subsidiaries and affiliates	2.00%		1.80%		2.70%
Other adjustments relating to prior years	0.40%		-1.50%		0.40%
Adjustments for unrecognized tax benefits	-3.90%		0.20%		-1.10%
Adjustments for change in income tax laws	1.20%	[1]	0.50%	[1]	8.30%	[1]
Other	-0.10%		0.00%		0.00%
Effective tax rate	34.70%		36.60%		52.70%
[1]	On November 30, 2011, the National Diet of Japan approved the laws for amendments to previous income tax laws. Upon the change in the laws, the statutory income tax rate in Japan for the year ended March 31, 2013 was changed to 37.9%. The tax rate will be changed to 35.1% for fiscal years beginning on or after April 1, 2015. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net deferred tax assets decreased ¥16,072 million, and income tax expenses increased ¥16,072 million, as of the enactment date of the laws. This impact is included in Adjustments for the change in income tax laws for the year ended March 31, 2012. The impact for the year ended March 31, 2013 is not material. On March 20, 2014, the National Diet of Japan approved amendments to existing income tax laws and the Special Reconstruction Corporation Tax imposed on companies will be abolished for fiscal years beginning on or after April 1, 2014. Upon the change in the laws, the statutory income tax rate in Japan for fiscal years beginning on or after April 1, 2014 will be changed to approximately 35%. Thus, the Company and its Japanese subsidiaries re-measured deferred tax assets and liabilities as of the enactment date based on the new tax rates to be applied in the fiscal years in which temporary differences are expected to be recovered or settled. As a result, net of deferred tax assets decreased ¥7,321 million, and income tax expenses increased ¥7,321 million, as of the enactment date of the laws.

Effective_Income_Tax_Rate_Pare

Effective Income Tax Rate (Parenthetical) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Reconciliation of Statutory Federal Tax Rate [Line Items]	'	'	'
Amendments to income tax laws, approved date	20-Mar-14	'	30-Nov-11
Statutory income tax rate (in percentage)	37.90%	37.90%	40.00%
Net of deferred tax assets decreased	¥ 7,321	'	¥ 16,072
Income tax expenses increased	¥ 7,321	'	¥ 16,072
Fiscal years beginning on or after April 1, 2012	'	'	'
Reconciliation of Statutory Federal Tax Rate [Line Items]	'	'	'
Statutory income tax rate (in percentage)	'	'	37.90%
Fiscal years beginning on or after April 1, 2015	'	'	'
Reconciliation of Statutory Federal Tax Rate [Line Items]	'	'	'
Statutory income tax rate (in percentage)	'	'	35.10%
Fiscal years beginning on or after April 1, 2014	'	'	'
Reconciliation of Statutory Federal Tax Rate [Line Items]	'	'	'
Statutory income tax rate (in percentage)	35.00%	'	'

Tax_Effects_of_Temporary_Diffe

Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Deferred tax assets:	'	'
Inventories	¥ 30,190	¥ 28,122
Allowance for dealers and customers	110,936	87,224
Accrued bonus	32,837	32,380
Property, plant and equipment	58,671	65,397
Operating loss carryforwards	107,269	138,559
Pension and other postretirement benefits	152,409	229,102
Other	188,057	166,894
Total gross deferred tax assets	680,369	747,678
Less valuation allowance	97,138	81,007
Net deferred tax assets	583,231	666,671
Deferred tax liabilities:	'	'
Inventories	-13,924	-16,575
Prepaid pension expenses	-4,977	-12,274
Property, plant and equipment, excluding lease transactions	-78,898	-80,103
Direct financing lease transactions	-26,658	-23,580
Operating lease transactions	-695,507	-623,535
Undistributed earnings of subsidiaries and affiliates	-112,085	-89,126
Net unrealized gains on available-for-sale securities	-33,709	-27,042
Other	-44,887	-51,727
Total gross deferred tax liabilities	-1,010,645	-923,962
Net deferred tax asset (liability)	¥ (427,414)	¥ (257,291)

Deferred_Income_Tax_Assets_and

Deferred Income Tax Assets and Liabilities (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]	'	'
Current assets-Deferred income taxes	¥ 202,123	¥ 234,075
Other assets	80,289	127,248
Other current liabilities	-3,164	-2,735
Other liabilities	-706,662	-615,879
Net deferred tax asset (liability)	¥ (427,414)	¥ (257,291)

Operating_Loss_and_Tax_Credit_

Operating Loss and Tax Credit Carryforwards (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Operating Loss and Tax Credit Carryforwards [Line Items]	'
Operating loss carryforwards	¥ 353,357
Tax credit carryforwards	34,578
Within 1 year	'
Operating Loss and Tax Credit Carryforwards [Line Items]	'
Operating loss carryforwards	434
Tax credit carryforwards	37
1 to 5 years	'
Operating Loss and Tax Credit Carryforwards [Line Items]	'
Operating loss carryforwards	12,975
Tax credit carryforwards	17,146
5 to 20 years	'
Operating Loss and Tax Credit Carryforwards [Line Items]	'
Operating loss carryforwards	222,937
Tax credit carryforwards	17,076
Indefinite periods	'
Operating Loss and Tax Credit Carryforwards [Line Items]	'
Operating loss carryforwards	117,011
Tax credit carryforwards	¥ 319

Reconciliations_of_Beginning_a

Reconciliations of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Reconciliation of Unrecognized Tax Benefits [Line Items]	'		'		'
Balance at beginning of year	¥ 39,151		¥ 43,627		¥ 46,265
Additions for tax positions related to current year	'		'		2,910
Additions for tax positions of prior years	3,332		687		4,538
Reductions for tax positions of prior years	-26,063	[1]	-7,855	[1]	-1,217	[1]
Settlements	-3,808		'		-1,688
Reductions for statute of limitations	-6,909		'		-6,894
Effect of exchange rate changes	1,280		2,692		-287
Balance at end of year	¥ 6,983		¥ 39,151		¥ 43,627
[1]	Due to the Company's remeasurement based on technical merits regarding transfer pricing matters of overseas transactions between the Company and foreign affiliates, the Company has decreased a portion of unrecognized tax benefits during the year ended March 31, 2014.

Dividends_and_Legal_Reserves_A

Dividends and Legal Reserves - Additional Information (Detail) (JPY ¥)	12 Months Ended			1 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Jun. 30, 2014
				Dividend declared
Stockholders Equity Note [Line Items]	'	'	'	'
Dividends and legal reserves requirements	'The Company Law of Japan provides that earnings in an amount equal to 10% of dividends of retained earnings shall be appropriated as a capital surplus or a legal reserve on the date of distribution of retained earnings until an aggregated amount of capital surplus and legal reserve equals 25% of stated capital.	'	'	'
Dividends per share (in yen per share)	¥ 79	¥ 72	¥ 60	¥ 22
Future dividend, aggregate	'	'	'	¥ 39,650
Future dividend, proposed and resolved in general shareholders' meeting, date	'	'	'	13-Jun-14

Reconciliations_of_Beginning_a1

Reconciliations of Beginning and Ending Balances of Pension Benefit Obligations and Fair Value of Plan Assets (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Amounts recognized in the consolidated balance sheets consist of:	'	'	'
Noncurrent liabilities	¥ (445,350)	¥ (622,462)	'
Japanese plans	'	'	'
Change in benefit obligations:	'	'	'
Benefit obligations at beginning of year	-1,283,216	-1,193,566	'
Service cost	-33,701	-31,124	-33,454
Interest cost	-19,248	-23,871	-23,481
Actuarial gain (loss)	-4,833	-82,834	'
Benefits paid	47,363	48,179	'
Benefit obligations at end of year	-1,293,635	-1,283,216	-1,193,566
Change in plan assets:	'	'	'
Fair value of plan assets at beginning of year	918,518	801,701	'
Actual return on plan assets	71,304	94,446	'
Employer contributions	69,580	70,550	'
Benefits paid	-47,363	-48,179	'
Fair value of plan assets at end of year	1,012,039	918,518	801,701
Funded status	-281,596	-364,698	'
Amounts recognized in the consolidated balance sheets consist of:	'	'	'
Noncurrent assets	2,626	1,480	'
Current liabilities	-335	-364	'
Noncurrent liabilities	-283,887	-365,814	'
Total	-281,596	-364,698	'
Amounts recognized in accumulated other comprehensive income (loss) consist of:	'	'	'
Actuarial loss (gain)	335,886	394,998	'
Prior service cost (benefit)	-105,367	-121,671	'
Total	230,519	273,327	'
Pension plans with accumulated benefit obligations in excess of plan assets:	'	'	'
Projected benefit obligations	-1,272,687	-1,262,263	'
Accumulated benefit obligations	-1,191,640	-1,180,781	'
Fair value of plan assets	988,744	897,066	'
Foreign plans	'	'	'
Change in benefit obligations:	'	'	'
Benefit obligations at beginning of year	-685,155	-536,064	'
Service cost	-27,342	-24,826	-19,506
Interest cost	-31,857	-26,107	-24,130
Plan participants' contributions	-13	-26	'
Actuarial gain (loss)	20,074	-33,210	'
Benefits paid	39,339	11,177	'
Amendment	57,251	'	'
Curtailment	1,084	'	'
Foreign currency translation	-63,053	-76,099	'
Benefit obligations at end of year	-689,672	-685,155	-536,064
Change in plan assets:	'	'	'
Fair value of plan assets at beginning of year	543,164	422,500	'
Actual return on plan assets	67,666	45,124	'
Employer contributions	33,557	23,795	'
Plan participants' contributions	13	26	'
Benefits paid	-39,339	-11,177	'
Foreign currency translation	51,891	62,896	'
Fair value of plan assets at end of year	656,952	543,164	422,500
Funded status	-32,720	-141,991	'
Amounts recognized in the consolidated balance sheets consist of:	'	'	'
Noncurrent assets	18,643	'	'
Current liabilities	-40	-38	'
Noncurrent liabilities	-51,323	-141,953	'
Total	-32,720	-141,991	'
Amounts recognized in accumulated other comprehensive income (loss) consist of:	'	'	'
Actuarial loss (gain)	145,979	206,941	'
Net transition obligation	35	77	'
Prior service cost (benefit)	-35,497	-1,905	'
Total	110,517	205,113	'
Pension plans with accumulated benefit obligations in excess of plan assets:	'	'	'
Projected benefit obligations	-469,569	-493,040	'
Accumulated benefit obligations	-469,152	-453,165	'
Fair value of plan assets	¥ 429,441	¥ 367,949	'

Pension_and_Other_Postretireme2

Pension and Other Postretirement Benefits - Additional Information (Detail) (JPY ¥)

12 Months Ended

12 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2012

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Selling, general and administrative expenses

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Japanese plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Foreign plans

Level 1

Level 1

Level 1

Level 1

Level 1

Level 1

Level 2

Level 2

Level 2

Level 2

Level 2

Level 2

Level 2

Level 2

Cost of sales

Selling, general and administrative expenses

Level 1

Level 1

Level 1

Level 1

Level 1

Level 1

Equity securities

Equity securities

Equity securities

Equity securities

Equity securities

Equity securities

Corporate, government, agency and local bonds

Corporate, government, agency and local bonds

Corporate, government, agency and local bonds

Corporate, government, agency and local bonds

Corporate, government, agency and local bonds

Corporate, government, agency and local bonds

Equity securities

Equity securities

Equity securities

Equity securities

Equity securities

Equity securities

Japan

Japan

United States

United States

Other Countries

Other Countries

Japan

Japan

United States

United States

Other Countries

Other Countries

Japan

Japan

United States

United States

Other Countries

Other Countries

Defined Benefit Plan Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Date of curtailment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1-Jan-14

'

'

'

'

'

'

'

'

'

Curtailment gain

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

¥ 21,368

'

¥ 15,407

¥ 5,961

'

'

'

'

'

'

Accumulated benefit obligations

'

1,209,003

1,197,913

'

'

'

'

'

'

'

'

'

'

'

'

'

'

645,939

610,517

'

'

'

'

'

'

'

'

Pension plan assets, allocations (in percentage)

'

'

'

8.00%

10.00%

45.00%

43.00%

47.00%

47.00%

'

'

18.00%

23.00%

23.00%

24.00%

59.00%

53.00%

'

'

'

'

5.00%

6.00%

58.00%

56.00%

37.00%

38.00%

Derivative instruments, asset position, gross

'

'

'

'

'

'

'

'

'

2,711

6,623

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative instruments, liability position, gross

'

'

'

'

'

'

'

'

'

5,924

4,129

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Expected contribution to pension plans in the year ending March 31, 2015

'

56,152

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

23,088

'

'

'

'

'

'

'

'

'

Cost of special early retirement support plan

¥ 10,354

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Pension_Expense_and_Other_Amou

Pension Expense and Other Amounts Recognized in Other Comprehensive Income (Loss) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Other amounts recognized in other comprehensive income (loss)	'		'		'
Total	¥ (163,101)	[1]	¥ 22,217	[1]	¥ 61,491	[1]
Japanese plans	'		'		'
Pension cost	'		'		'
Service cost-benefits earned during the year	33,701		31,124		33,454
Interest cost on projected benefit obligations	19,248		23,871		23,481
Expected return on plan assets	-25,341		-24,048		-23,645
Amortization of actuarial loss (gain)	17,218		18,149		20,373
Amortization of prior service cost (benefit)	-16,304		-16,304		-16,304
Total	28,522		32,792		37,359
Other amounts recognized in other comprehensive income (loss)	'		'		'
Actuarial loss (gain)	-41,894		10,137		-13,305
Amortization of actuarial loss (gain)	-17,218		-18,149		-20,373
Amortization of prior service cost (benefit)	16,304		16,304		16,304
Total	-42,808		8,292		-17,374
Total recognized in pension cost and other comprehensive income (loss)	-14,286		41,084		19,985
Foreign plans	'		'		'
Pension cost	'		'		'
Service cost-benefits earned during the year	27,342		24,826		19,506
Interest cost on projected benefit obligations	31,857		26,107		24,130
Expected return on plan assets	-39,624		-30,254		-26,796
Amortization of actuarial loss (gain)	12,538		10,724		5,829
Amortization of net transition obligation	42		33		30
Amortization of prior service cost (benefit)	-2,291		-205		6
Curtailment gain	-21,368		'		'
Other	'		17		3
Total	8,496		31,248		22,708
Other amounts recognized in other comprehensive income (loss)	'		'		'
Actuarial loss (gain)	-48,424		16,466		71,160
Amortization of actuarial loss (gain)	-12,538		-10,724		-5,829
Amortization of net transition obligation	-42		-33		-30
Prior service cost (benefit)	-57,251		41		-2,677
Amortization of prior service cost (benefit)	2,291		205		-6
Curtailment gain	21,368		'		'
Total	-94,596		5,955		62,618
Total recognized in pension cost and other comprehensive income (loss)	¥ (86,100)		¥ 37,203		¥ 85,326
[1]	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Estimated_Amounts_to_Be_Amorti

Estimated Amounts to Be Amortized from Accumulated Other Comprehensive Income (Loss) into Net Periodic Benefit Cost over Next Fiscal Year (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014
Japanese plans	'
Schedule of Estimated Amounts to Be Amortized from Accumulated Other Comprehensive Income (Loss) into Net Periodic Benefit Cost over Next Fiscal Year [Line Items]	'
Amortization of actuarial loss (gain)	¥ 13,451
Amortization of prior service cost (benefit)	-16,304
Foreign plans	'
Schedule of Estimated Amounts to Be Amortized from Accumulated Other Comprehensive Income (Loss) into Net Periodic Benefit Cost over Next Fiscal Year [Line Items]	'
Amortization of actuarial loss (gain)	12,019
Amortization of net transition obligation	3
Amortization of prior service cost (benefit)	¥ (3,371)

Weightedaverage_Assumptions_Us

Weighted-average Assumptions Used to Determine Benefit Obligation (Detail)	Mar. 31, 2014	Mar. 31, 2013
Japanese plans	'	'
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]	'	'
Discount rate	1.50%	1.50%
Rate of salary increase	2.20%	2.20%
Foreign plans | Minimum	'	'
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]	'	'
Discount rate	4.60%	4.50%
Rate of salary increase	2.50%	2.50%
Foreign plans | Maximum	'	'
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]	'	'
Discount rate	4.80%	4.70%
Rate of salary increase	3.90%	4.10%

Weightedaverage_Assumptions_Us1

Weighted-average Assumptions Used to Determine Net Periodic Benefit Cost (Detail)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Japanese plans	'	'	'
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]	'	'	'
Discount rate	1.50%	2.00%	2.00%
Rate of salary increase	2.20%	2.10%	2.20%
Expected long-term rate of return	3.00%	3.00%	3.00%
Foreign plans | Minimum	'	'	'
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]	'	'	'
Discount rate	4.50%	4.60%	5.50%
Rate of salary increase	2.50%	1.50%	1.50%
Expected long-term rate of return	6.00%	6.20%	6.50%
Foreign plans | Maximum	'	'	'
Schedule of Net Periodic Benefit Costs Weighted Average Assumptions [Line Items]	'	'	'
Discount rate	4.70%	5.20%	6.00%
Rate of salary increase	4.10%	4.40%	4.60%
Expected long-term rate of return	7.40%	7.70%	7.50%

Fair_Value_of_Japanese_Pension

Fair Value of Japanese Pension Plan Assets by Asset Category (Detail) (Japanese plans, JPY ¥)	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
In Millions, unless otherwise specified
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	¥ 1,012,039	¥ 918,518	¥ 801,701
Cash and cash equivalents	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	20,438	25,534	'
Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	349,857	313,027	'
Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	10,256	9,815	'
Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	363,605	311,577	'
General accounts	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	23,688	21,042	'
Separate accounts	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	11,625	10,773	'
Hedge funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	95,860	85,391	'
Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	139,923	138,865	'
Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	-3,213	2,494	'
Level 1	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	636,069	438,182	'
Level 1 | Cash and cash equivalents	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	20,438	25,534	'
Level 1 | Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	349,601	312,764	'
Level 1 | Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	8,341	4,320	'
Level 1 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	256,114	93,450	'
Level 1 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	1,559	2,033	'
Level 1 | Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	16	81	'
Level 2	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	278,736	393,551	'
Level 2 | Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	254	263	'
Level 2 | Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	1,829	5,477	'
Level 2 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	107,491	217,964	'
Level 2 | General accounts	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	23,688	21,042	'
Level 2 | Separate accounts	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	11,625	10,773	'
Level 2 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	137,078	135,619	'
Level 2 | Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	-3,229	2,413	'
Level 3	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	97,234	86,785	63,551
Level 3 | Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	2	'	180
Level 3 | Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	86	18	'
Level 3 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	'	163	100
Level 3 | Hedge funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	95,860	85,391	63,271
Level 3 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	¥ 1,286	¥ 1,213	'

Reconciliations_for_Level_3_Ja

Reconciliations for Level 3 Japanese Pension Plan Assets (Detail) (Japanese plans, JPY ¥)

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

In Millions, unless otherwise specified

Equity securities

Equity securities

Corporate bonds

Corporate bonds

Government, agency and local bonds

Government, agency and local bonds

Hedge funds

Hedge funds

Commingled and other mutual funds

Commingled and other mutual funds

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Level 3

Equity securities

Equity securities

Corporate bonds

Corporate bonds

Government, agency and local bonds

Government, agency and local bonds

Hedge funds

Hedge funds

Commingled and other mutual funds

Commingled and other mutual funds

Defined Benefit Plan Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value of plan assets at beginning of year

¥ 1,012,039

¥ 918,518

¥ 801,701

¥ 349,857

¥ 313,027

¥ 10,256

¥ 9,815

¥ 363,605

¥ 311,577

¥ 95,860

¥ 85,391

¥ 139,923

¥ 138,865

¥ 86,785

¥ 63,551

'

¥ 180

¥ 18

'

¥ 163

¥ 100

¥ 85,391

¥ 63,271

¥ 1,213

'

Actual return on plan assets:

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Relating to assets still held at the reporting date

'

'

'

'

'

'

'

'

'

'

'

'

'

9,677

10,519

'

'

4

'

'

22

9,600

10,484

73

13

Relating to assets sold during the period

'

'

'

'

'

'

'

'

'

'

'

'

'

647

865

'

60

'

'

3

1

644

804

'

'

Purchases, sales and settlements, net

'

'

'

'

'

'

'

'

'

'

'

'

'

152

11,850

2

-240

64

18

-139

40

225

10,832

'

1,200

Transfers in and/or out of Level 3

'

'

'

'

'

'

'

'

'

'

'

'

'

-27

'

'

'

'

'

-27

'

'

'

'

'

Fair value of plan assets at end of year

¥ 1,012,039

¥ 918,518

¥ 801,701

¥ 349,857

¥ 313,027

¥ 10,256

¥ 9,815

¥ 363,605

¥ 311,577

¥ 95,860

¥ 85,391

¥ 139,923

¥ 138,865

¥ 97,234

¥ 86,785

¥ 2

'

¥ 86

¥ 18

'

¥ 163

¥ 95,860

¥ 85,391

¥ 1,286

¥ 1,213

Fair_Value_of_Foreign_Pension_

Fair Value of Foreign Pension Plan Assets by Asset Category (Detail) (Foreign plans, JPY ¥)	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
In Millions, unless otherwise specified
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	¥ 656,952	¥ 543,164	¥ 422,500
Cash and cash equivalents	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	6,597	6,178	'
Short-term investments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	12,353	11,529	'
Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	205,301	157,704	'
Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	62,149	51,942	'
Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	58,355	45,657	'
Real estate funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	35,856	26,995	'
Private equity funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	33,215	22,946	'
Hedge funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	35,807	28,695	'
Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	201,379	187,631	'
Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	765	57	'
Asset-backed securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	5,175	3,830	'
Level 1	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	212,312	167,801	'
Level 1 | Cash and cash equivalents	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	6,597	6,178	'
Level 1 | Short-term investments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	462	742	'
Level 1 | Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	201,787	157,704	'
Level 1 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	4,170	2,868	'
Level 1 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	'	309	'
Level 1 | Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	-704	'	'
Level 2	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	322,362	285,357	'
Level 2 | Short-term investments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	11,891	10,787	'
Level 2 | Equity securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	3,514	'	'
Level 2 | Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	61,883	51,660	'
Level 2 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	54,136	42,416	'
Level 2 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	184,288	176,534	'
Level 2 | Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	1,475	130	'
Level 2 | Asset-backed securities	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	5,175	3,830	'
Level 3	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	122,278	90,006	46,758
Level 3 | Corporate bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	266	282	'
Level 3 | Government, agency and local bonds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	49	373	'
Level 3 | Real estate funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	35,856	26,995	15,190
Level 3 | Private equity funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	33,215	22,946	10,030
Level 3 | Hedge funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	35,807	28,695	19,726
Level 3 | Commingled and other mutual funds	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	17,091	10,788	1,840
Level 3 | Derivative instruments	'	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'	'
Fair value of pension plan assets	¥ (6)	¥ (73)	¥ (28)

Reconciliations_for_Level_3_Fo

Reconciliations for Level 3 Foreign Pension Plan Assets (Detail) (Foreign plans, JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	¥ 543,164	¥ 422,500
Actual return on plan assets:	'	'
Foreign currency translation	51,891	62,896
Fair value of plan assets at end of year	656,952	543,164
Corporate bonds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	62,149	51,942
Government, agency and local bonds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	58,355	45,657
Real estate funds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	35,856	26,995
Private equity funds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	33,215	22,946
Hedge funds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	35,807	28,695
Commingled and other mutual funds	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	201,379	187,631
Derivative instruments	'	'
Actual return on plan assets:	'	'
Fair value of plan assets at end of year	765	57
Level 3	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	90,006	46,758
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	7,741	4,058
Relating to assets sold during the period	401	317
Purchases, sales and settlements, net	14,605	28,418
Transfers in and/or out of Level 3	-445	390
Foreign currency translation	9,970	10,065
Fair value of plan assets at end of year	122,278	90,006
Level 3 | Corporate bonds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	282	'
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	-12	-2
Relating to assets sold during the period	-3	11
Purchases, sales and settlements, net	21	70
Transfers in and/or out of Level 3	-48	171
Foreign currency translation	26	32
Fair value of plan assets at end of year	266	282
Level 3 | Government, agency and local bonds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	373	'
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	2	7
Relating to assets sold during the period	'	7
Purchases, sales and settlements, net	45	95
Transfers in and/or out of Level 3	-397	219
Foreign currency translation	26	45
Fair value of plan assets at end of year	49	373
Level 3 | Real estate funds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	26,995	15,190
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	2,403	1,010
Relating to assets sold during the period	2	-2
Purchases, sales and settlements, net	3,499	7,935
Foreign currency translation	2,957	2,862
Fair value of plan assets at end of year	35,856	26,995
Level 3 | Private equity funds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	22,946	10,030
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	1,778	898
Relating to assets sold during the period	401	291
Purchases, sales and settlements, net	6,355	9,056
Foreign currency translation	1,735	2,671
Fair value of plan assets at end of year	33,215	22,946
Level 3 | Hedge funds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	28,695	19,726
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	3,217	1,537
Relating to assets sold during the period	'	3
Purchases, sales and settlements, net	1,075	3,869
Foreign currency translation	2,820	3,560
Fair value of plan assets at end of year	35,807	28,695
Level 3 | Commingled and other mutual funds	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	10,788	1,840
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	353	606
Purchases, sales and settlements, net	3,539	7,438
Foreign currency translation	2,411	904
Fair value of plan assets at end of year	17,091	10,788
Level 3 | Derivative instruments	'	'
Schedule of Pension and Other Postretirement Plan Assets by Fair Value [Line Items]	'	'
Fair value of plan assets at beginning of year	-73	-28
Actual return on plan assets:	'	'
Relating to assets still held at the reporting date	'	2
Relating to assets sold during the period	1	7
Purchases, sales and settlements, net	71	-45
Foreign currency translation	-5	-9
Fair value of plan assets at end of year	¥ (6)	¥ (73)

Estimated_Future_Gross_Benefit

Estimated Future Gross Benefit Payments (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Japanese plans	'
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]	'
2015	¥ 46,670
2016	47,386
2017	48,683
2018	50,984
2019	53,616
2020-2024	298,741
Foreign plans	'
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items]	'
2015	23,297
2016	24,904
2017	26,797
2018	29,143
2019	32,020
2020-2024	¥ 198,433

Supplemental_Disclosures_of_Ca2

Supplemental Disclosures of Cash Flow Information (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Cash paid (provided), net during the year for:	'	'	'
Interest	¥ 82,796	¥ 86,989	¥ 97,788
Income taxes	¥ 240,668	¥ 138,583	¥ 47,217

Changes_in_Accumulated_Other_C

Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Adjustments from foreign currency translation	'		'		'
Balance at beginning of year	¥ (969,583)		¥ (1,385,045)		¥ (1,268,233)
Other comprehensive income (loss) before reclassifications	333,022		430,812		-118,135
Amounts reclassified from accumulated other comprehensive income (loss)	637		'		'
Net unrealized gains (losses)	333,659		430,812		-118,135
Less: Other comprehensive income attributable to noncontrolling interests	13,235		15,350		-1,323
Balance at end of year	-649,159		-969,583		-1,385,045
Unrealized gains (losses) on available-for-sale securities, net	'		'		'
Balance at beginning of year	44,131		36,198		30,299
Other comprehensive income (loss) before reclassifications	15,975		7,968		6,351
Amounts reclassified from accumulated other comprehensive income (loss)	-723		16		-539
Net unrealized gains (losses)	15,252		7,984		5,812
Less: Other comprehensive income attributable to noncontrolling interests	33		51		-87
Balance at end of year	59,350		44,131		36,198
Unrealized gains (losses) on derivative instruments, net	'		'		'
Balance at beginning of year	-237		-185		-156
Other comprehensive income (loss) before reclassifications	-19		-797		-76
Amounts reclassified from accumulated other comprehensive income (loss)	256		745		47
Net unrealized gains (losses)	237		-52		-29
Less: Other comprehensive income attributable to noncontrolling interests	'		'		'
Balance at end of year	0		-237		-185
Pension and other postretirement benefits adjustments	'		'		'
Balance at beginning of year	-311,103		-297,046		-257,290
Other comprehensive income (loss) before reclassifications	112,952	[1]	-24,534	[1]	-46,543	[1]
Amounts reclassified from accumulated other comprehensive income (loss)	-5,234	[1]	9,237	[1]	6,890	[1]
Net unrealized gains (losses)	107,718	[1]	-15,297	[1]	-39,653	[1]
Less: Other comprehensive income attributable to noncontrolling interests	-180		-1,240		103
Balance at end of year	-203,205		-311,103		-297,046
Total accumulated other comprehensive income (loss)	'		'		'
Balance at beginning of year	-1,236,792		-1,646,078		-1,495,380
Other comprehensive income (loss) before reclassifications	461,930		413,449		-158,403
Amounts reclassified from accumulated other comprehensive income (loss)	-5,064		9,998		6,398
Other comprehensive income (loss)	456,866		423,447		-152,005
Less: Other comprehensive income attributable to noncontrolling interests	13,088		14,161		-1,307
Balance at end of year	¥ (793,014)		¥ (1,236,792)		¥ (1,646,078)
[1]	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Reclassifications_out_of_Accum

Reclassifications out of Accumulated Other Comprehensive Income (Loss) by Component (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013	Mar. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Other income (expenses) - Other, net	¥ (32,664)		¥ (69,504)	¥ 2,956
Income tax expense	-252,662		-178,976	-135,735
Net income	608,749		392,638	222,074
Reclassification out of Accumulated Other Comprehensive Income [Member]	'		'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Net income	5,064		'	'
Adjustments from foreign currency translation | Reclassification out of Accumulated Other Comprehensive Income [Member]	'		'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Other income (expenses) - Other, net	-1,027		'	'
Income tax expense	390		'	'
Net income	-637		'	'
Unrealized gains (losses) on available-for-sale securities, net | Reclassification out of Accumulated Other Comprehensive Income [Member]	'		'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Other income (expenses) - Other, net	1,114		'	'
Income tax expense	-391		'	'
Net income	723		'	'
Unrealized gains (losses) on derivative instruments, net | Reclassification out of Accumulated Other Comprehensive Income [Member]	'		'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Other income (expenses) - Other, net	-411		'	'
Income tax expense	155		'	'
Net income	-256		'	'
Pension and other postretirement benefits adjustments | Reclassification out of Accumulated Other Comprehensive Income [Member]	'		'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'		'	'
Net periodic pension cost	8,823	[1]	'	'
Income tax expense	-3,589		'	'
Net income	¥ 5,234		'	'
[1]	This accumulated other comprehensive income (loss) components is included in the computation of net periodic pension cost.

Tax_Effects_Allocated_to_Each_

Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss) and Reclassification Adjustments (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Adjustments from foreign currency translation, before-tax:	'		'		'
Unrealized gains (losses) arising during the year	¥ 343,695		¥ 433,640		¥ (119,910)
Reclassification adjustments for losses (gains) realized in net income	1,027		'		'
Net unrealized gains (losses)	344,722		433,640		-119,910
Unrealized gains (losses) on available-for-sale securities, before-tax:	'		'		'
Unrealized holding gains (losses) arising during the year	22,261		12,336		9,438
Reclassification adjustments for losses (gains) realized in net income	-1,114		24		-706
Net unrealized gains (losses)	21,147		12,360		8,732
Unrealized gains (losses) on derivative instruments, before-tax:	'		'		'
Unrealized holding gains (losses) arising during the year	-29		-1,281		-115
Reclassification adjustments for losses (gains) realized in net income	411		1,197		78
Net unrealized gains (losses)	382		-84		-37
Pension and other postretirement benefits adjustments, before-tax:	'		'		'
(Increase) decrease in net unrealized losses on pension and other postretirement benefits	171,924	[1]	-36,611	[1]	-72,225	[1]
Amortization of unrealized (gain) loss on pension and other postretirement benefits	-8,823	[1]	14,394	[1]	10,734	[1]
Net unrealized gains (losses)	163,101	[1]	-22,217	[1]	-61,491	[1]
Other comprehensive income (loss)	529,352		423,699		-172,706
Adjustments from foreign currency translation, tax (expense) or benefit (note 11):	'		'		'
Unrealized gains (losses) arising during the year	-10,673		-2,828		1,775
Reclassification adjustments for losses (gains) realized in net income	-390		'		'
Net unrealized gains (losses)	-11,063		-2,828		1,775
Unrealized gains (losses) on available-for-sale securities, tax (expense) or benefit (note 11):	'		'		'
Unrealized holding gains (losses) arising during the year	-6,286		-4,368		-3,087
Reclassification adjustments for losses (gains) realized in net income	391		-8		167
Net unrealized gains (losses)	-5,895		-4,376		-2,920
Unrealized gains (losses) on derivative instruments, tax (expense) or benefit (note 11):	'		'		'
Unrealized holding gains (losses) arising during the year	10		484		39
Reclassification adjustments for losses (gains) realized in net income	-155		-452		-31
Net unrealized gains (losses)	-145		32		8
Pension and other postretirement benefits adjustments, tax (expense) or benefit (note 11):	'		'		'
(Increase) decrease in net unrealized losses on pension and other postretirement benefits	-58,972	[1]	12,077	[1]	25,682	[1]
Amortization of unrealized (gain) loss on pension and other postretirement benefits	3,589	[1]	-5,157	[1]	-3,844	[1]
Net unrealized gains (losses)	-55,383	[1]	6,920	[1]	21,838	[1]
Other comprehensive income (loss)	-72,486		-252		20,701
Adjustments from foreign currency translation, net-of-tax:	'		'		'
Unrealized gains (losses) arising during the year	333,022		430,812		-118,135
Reclassification adjustments for losses (gains) realized in net income	637		'		'
Net unrealized gains (losses)	333,659		430,812		-118,135
Unrealized gains (losses) on available-for-sale securities, net-of-tax:	'		'		'
Unrealized holding gains (losses) arising during the year	15,975		7,968		6,351
Reclassification adjustments for losses (gains) realized in net income	-723		16		-539
Net unrealized gains (losses)	15,252		7,984		5,812
Unrealized gains (losses) on derivative instruments, net-of-tax:	'		'		'
Unrealized holding gains (losses) arising during the year	-19		-797		-76
Reclassification adjustments for losses (gains) realized in net income	256		745		47
Net unrealized gains (losses)	237		-52		-29
Pension and other postretirement benefits adjustments, net-of-tax:	'		'		'
(Increase) decrease in net unrealized losses on pension and other postretirement benefits	112,952	[1]	-24,534	[1]	-46,543	[1]
Amortization of unrealized (gain) loss on pension and other postretirement benefits	-5,234	[1]	9,237	[1]	6,890	[1]
Net unrealized gains (losses)	107,718	[1]	-15,297	[1]	-39,653	[1]
Other comprehensive income (loss)	¥ 456,866		¥ 423,447		¥ (152,005)
[1]	The primary components of other comprehensive income (loss) for Pension and other postretirement benefits adjustments are actuarial gains or losses and prior service benefits or costs (note 13).

Assets_and_Liabilities_Measure

Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Assets:	'	'
Available-for-sale securities	¥ 185,960	¥ 128,848
Fair value on a recurring basis	'	'
Assets:	'	'
Derivative instruments	20,046	20,619
Available-for-sale securities	185,960	128,848
Total	206,006	149,467
Liabilities:	'	'
Derivative instruments	-14,935	-75,502
Total	-14,935	-75,502
Fair value on a recurring basis | Marketable equity securities	'	'
Assets:	'	'
Available-for-sale securities	138,476	117,110
Fair value on a recurring basis | Auction rate securities	'	'
Assets:	'	'
Available-for-sale securities	6,999	6,928
Fair value on a recurring basis | Debt securities	'	'
Assets:	'	'
Available-for-sale securities	31,905	4,226
Fair value on a recurring basis | Others	'	'
Assets:	'	'
Available-for-sale securities	8,580	584
Fair value on a recurring basis | Level 1	'	'
Assets:	'	'
Available-for-sale securities	143,622	117,694
Total	143,622	117,694
Fair value on a recurring basis | Level 1 | Marketable equity securities	'	'
Assets:	'	'
Available-for-sale securities	138,476	117,110
Fair value on a recurring basis | Level 1 | Others	'	'
Assets:	'	'
Available-for-sale securities	5,146	584
Fair value on a recurring basis | Level 2	'	'
Assets:	'	'
Derivative instruments	30,850	38,690
Available-for-sale securities	35,339	4,226
Total	66,189	42,916
Liabilities:	'	'
Derivative instruments	-25,739	-93,573
Total	-25,739	-93,573
Fair value on a recurring basis | Level 2 | Foreign exchange instruments (notes 1(q) and 17)	'	'
Assets:	'	'
Derivative instruments	11,036	6,538
Liabilities:	'	'
Derivative instruments	-14,852	-78,934
Fair value on a recurring basis | Level 2 | Interest rate instruments (notes 1(q) and 17)	'	'
Assets:	'	'
Derivative instruments	19,814	32,152
Liabilities:	'	'
Derivative instruments	-10,887	-14,639
Fair value on a recurring basis | Level 2 | Debt securities	'	'
Assets:	'	'
Available-for-sale securities	31,905	4,226
Fair value on a recurring basis | Level 2 | Others	'	'
Assets:	'	'
Available-for-sale securities	3,434	'
Fair value on a recurring basis | Level 3	'	'
Assets:	'	'
Available-for-sale securities	6,999	6,928
Total	6,999	6,928
Fair value on a recurring basis | Level 3 | Auction rate securities	'	'
Assets:	'	'
Available-for-sale securities	6,999	6,928
Fair value on a recurring basis | Gross fair value	'	'
Assets:	'	'
Derivative instruments	30,850	38,690
Available-for-sale securities	185,960	128,848
Total	216,810	167,538
Liabilities:	'	'
Derivative instruments	-25,739	-93,573
Total	-25,739	-93,573
Fair value on a recurring basis | Gross fair value | Foreign exchange instruments (notes 1(q) and 17)	'	'
Assets:	'	'
Derivative instruments	11,036	6,538
Liabilities:	'	'
Derivative instruments	-14,852	-78,934
Fair value on a recurring basis | Gross fair value | Interest rate instruments (notes 1(q) and 17)	'	'
Assets:	'	'
Derivative instruments	19,814	32,152
Liabilities:	'	'
Derivative instruments	-10,887	-14,639
Fair value on a recurring basis | Gross fair value | Marketable equity securities	'	'
Assets:	'	'
Available-for-sale securities	138,476	117,110
Fair value on a recurring basis | Gross fair value | Auction rate securities	'	'
Assets:	'	'
Available-for-sale securities	6,999	6,928
Fair value on a recurring basis | Gross fair value | Debt securities	'	'
Assets:	'	'
Available-for-sale securities	31,905	4,226
Fair value on a recurring basis | Gross fair value | Others	'	'
Assets:	'	'
Available-for-sale securities	8,580	584
Fair value on a recurring basis | Netting adjustment	'	'
Assets:	'	'
Derivative instruments	-10,804	-18,071
Total	-10,804	-18,071
Liabilities:	'	'
Derivative instruments	10,804	18,071
Total	¥ 10,804	¥ 18,071

Reconciliations_for_All_Level_

Reconciliations for All Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Auction rate securities, Level 3, JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Auction rate securities | Level 3	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance at beginning of year	¥ 6,928	¥ 6,651
Total realized/unrealized gains or losses	'	'
Included in earnings	'	'
Included in other comprehensive income (loss)	202	115
Purchases, issuances, settlements and sales	'	'
Purchases	'	'
Issuances	'	'
Settlements	'	'
Sales	-790	-691
Foreign currency translation	659	853
Balance at end of year	6,999	6,928
The amounts of total gains or losses for the period attributable to the change in unrealized gains or losses relating to assets and liabilities still held at the reporting date	'	'
Included in earnings	'	'
Included in other comprehensive income (loss)	¥ 103	¥ 115

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified	Level 3	Fair value on a nonrecurring basis
	Auction rate securities	Level 1
	AAA credit rating
	United States Government guarantee
Fair Value, Measurement Inputs, Disclosure [Line Items]	'	'
Subsidiary's auction rate securities holdings, percentage guaranteed by the United States Government (in percentage)	95.00%	'
Certain investments in affiliates which have quoted market values at fair value on nonrecurring basis due to recognition of impairment loss (note 6)	'	¥ 68,778

Estimated_Fair_Values_of_Signi

Estimated Fair Values of Significant Financial Instruments (Detail) (JPY ¥)	Mar. 31, 2014		Mar. 31, 2013
In Millions, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Finance subsidiaries-receivables	¥ 5,533,997		¥ 4,704,330
Held-to-maturity securities	34,650		16,511
Carrying amount	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Held-to-maturity securities	34,650		16,511
Debt	-5,856,874		-4,894,188
Carrying amount | Finance subsidiaries-receivables, excluding direct financing leases, net	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Finance subsidiaries-receivables	5,140,064	[1]	4,278,460	[1]
Estimated fair value	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Held-to-maturity securities	34,667		16,556
Debt	-5,917,087		-4,966,318
Estimated fair value | Finance subsidiaries-receivables, excluding direct financing leases, net	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Finance subsidiaries-receivables	¥ 5,175,564	[1]	¥ 4,326,333	[1]
[1]	The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table exclude ¥425,870 million and ¥393,933 million, respectively, of direct financing leases, net, classified as finance subsidiaries-receivables in the consolidated balance sheets. The carrying amounts of finance subsidiaries-receivables at March 31, 2013 and 2014 in the table also include ¥673,193 million and ¥752,229 million of finance receivables classified as trade accounts and notes receivable and other assets in the consolidated balance sheets, respectively.

Estimated_Fair_Values_of_Signi1

Estimated Fair Values of Significant Financial Instruments (Parenthetical) (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Finance subsidiaries-receivables	¥ 5,533,997	¥ 4,704,330
Finance subsidiaries-receivables, excluding direct financing leases, net | Trade accounts and notes receivable and other assets	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Finance subsidiaries-receivables	752,229	673,193
Direct financing lease | Finance subsidiaries-receivables	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'
Finance subsidiaries-receivables	¥ 393,933	¥ 425,870

Contract_Amounts_Outstanding_f

Contract Amounts Outstanding for Foreign Exchange Instruments and Notional Principal Amounts of Interest Rate Instruments (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Foreign exchange instruments | Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	'	¥ 23,324
Foreign exchange instruments | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	876,486	1,065,834
Foreign currency forward exchange contracts | Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	'	23,324
Foreign currency forward exchange contracts | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	506,734	724,435
Foreign currency option contracts | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	3,721	4,145
Currency swap agreements | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	366,031	337,254
Interest rate instruments | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	4,809,037	4,063,289
Interest rate swap agreements | Not Designated as Hedging Instrument	'	'
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'
Contract amounts outstanding and notional principal amounts	¥ 4,809,037	¥ 4,063,289

Risk_Management_Activities_and2

Risk Management Activities and Derivative Financial Instruments - Additional Information (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Derivative Instruments and Hedging Activities Disclosure [Line Items]	'	'	'	'
Amount recognized in accumulated other comprehensive income (loss)	¥ 0	¥ (237)	¥ (185)	¥ (156)
Period that hedges changes in cash flows related to risk of foreign currency rate	'0 years 2 months 0 days	'	'	'

Estimated_Fair_Values_of_Deriv

Estimated Fair Values of Derivative Instruments (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	¥ 20,046	¥ 20,619
Derivatives not designated as hedging instruments: Liability derivatives	-14,935	-75,291
Other current assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	5,503	2,373
Other assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	14,543	18,246
Other current liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Liability derivatives	-14,935	-75,291
Foreign exchange instruments	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives designated as hedging instruments: Asset derivatives	'	'
Derivatives designated as hedging instruments: Liability derivatives	'	-211
Derivatives not designated as hedging instruments: Asset derivatives	11,036	6,538
Derivatives not designated as hedging instruments: Liability derivatives	-14,852	-78,723
Foreign exchange instruments | Other current assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives designated as hedging instruments: Asset derivatives	'	'
Derivatives not designated as hedging instruments: Asset derivatives	4,910	-1,534
Foreign exchange instruments | Other assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives designated as hedging instruments: Asset derivatives	'	'
Derivatives not designated as hedging instruments: Asset derivatives	2,288	-314
Foreign exchange instruments | Other current liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives designated as hedging instruments: Liability derivatives	'	-211
Derivatives not designated as hedging instruments: Liability derivatives	-11,014	-70,337
Interest rate instruments	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	19,814	32,152
Derivatives not designated as hedging instruments: Liability derivatives	-10,887	-14,639
Interest rate instruments | Other current assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	593	3,907
Interest rate instruments | Other assets	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	12,255	18,560
Interest rate instruments | Other current liabilities	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Liability derivatives	-3,921	-4,954
Total	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	30,850	38,690
Derivatives not designated as hedging instruments: Liability derivatives	-25,739	-93,362
Netting adjustment	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivatives not designated as hedging instruments: Asset derivatives	-10,804	-18,071
Derivatives not designated as hedging instruments: Liability derivatives	¥ 10,804	¥ 18,071

Pretax_Effects_of_Derivative_I

Pre-tax Effects of Derivative Instruments on the Company's Results of Operations (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Other income (expenses) - Other, net	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivatives not designated as hedging instruments: Gain (Loss) recognized in earnings	¥ (34,312)	¥ (107,792)	¥ (5,130)
Foreign exchange instruments	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivatives designated as hedging instruments: Gain (Loss) recognized in other comprehensive income (loss) (effective portion)	-29	-1,281	-115
Foreign exchange instruments | Other income (expenses) - Other, net	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivatives designated as hedging instruments: Gain (Loss) reclassified from accumulated other comprehensive income (loss) into earnings (effective portion)	-411	-1,197	-78
Derivatives designated as hedging instruments: Gain (Loss) recognized in earnings (financial instruments' time value component excluded from assessment of hedge effectiveness)	-714	-589	-455
Derivatives not designated as hedging instruments: Gain (Loss) recognized in earnings	-23,765	-111,004	-3,709
Interest rate instruments | Other income (expenses) - Other, net	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Derivatives not designated as hedging instruments: Gain (Loss) recognized in earnings	¥ (10,547)	¥ 3,212	¥ (1,421)

Commitments_and_Contingent_Lia2

Commitments and Contingent Liabilities - Additional Information (Detail) (JPY ¥)	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified
Guarantee and indemnification agreements	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'
Guarantee on bank loans of employees for their housing costs	¥ 25,368	¥ 26,475
Undiscounted maximum amount of Honda's obligation to make future payments	25,368	26,475
Amount accrued for estimated losses under the obligations	0	'
Commitments for purchases of property, plant and equipment and other commitments	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'
Commitments for purchases of property, plant and equipment and other commitments	¥ 131,238	'

Changes_in_Accrued_Liabilities

Changes in Accrued Liabilities for Product Warranties (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Product Liability Contingency [Line Items]	'	'
Balance at beginning of year	¥ 208,033	¥ 170,562
Warranty claims paid during the period	-104,090	-64,942
Liabilities accrued for warranties issued during the period	153,898	97,108
Changes in liabilities for pre-existing warranties during the period	397	-8,583
Foreign currency translation	11,382	13,888
Balance at end of year	¥ 269,620	¥ 208,033

Future_Minimum_Lease_Payments_

Future Minimum Lease Payments under Noncancelable Operating Leases (Detail) (JPY ¥)	Mar. 31, 2014
In Millions, unless otherwise specified
Schedule of Operating Leases [Line Items]	'
2015	¥ 18,862
2016	14,466
2017	13,101
2018	8,423
2019	7,604
After five years	39,724
Total minimum lease payments	¥ 102,180

Leases_Additional_Information_

Leases - Additional Information (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Leases Disclosure [Line Items]	'	'	'
Rental expenses under operating leases	¥ 34,953	¥ 32,728	¥ 34,079

Valuation_and_Qualifying_Accou2

Valuation and Qualifying Accounts (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Trade accounts and notes receivable: Allowance for doubtful accounts	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	¥ 7,885		¥ 7,293		¥ 7,904
Additions - Charged to costs and expenses	3,290		2,810		3,773
Deductions	2,094	[1]	2,721	[1]	3,858	[1]
Foreign currency translation	596		503		-526
Balance at end of year	9,677		7,885		7,293
Finance subsidiaries-receivables:	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	21,182		25,982		32,115
Additions - Charged to costs and expenses	18,904		10,059		13,032
Deductions	17,807	[1]	16,376	[1]	18,438	[1]
Foreign currency translation	1,411		1,517		-727
Balance at end of year	23,690		21,182		25,982
Allowance for credit losses	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	17,828		20,616		24,890
Additions - Charged to costs and expenses	18,503		9,234		11,625
Deductions	16,136	[1]	13,198	[1]	15,484	[1]
Foreign currency translation	1,364		1,176		-415
Balance at end of year	21,559		17,828		20,616
Allowance for losses on lease residual values	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	3,354		5,366		7,225
Additions - Charged to costs and expenses	401		825		1,407
Deductions	1,671	[1]	3,178	[1]	2,954	[1]
Foreign currency translation	47		341		-312
Balance at end of year	2,131		3,354		5,366
Other assets: Allowance for doubtful accounts	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	22,754		23,036		23,275
Additions - Charged to costs and expenses	175		687		1,293
Deductions	881	[1]	1,063	[1]	1,311	[1]
Foreign currency translation	52		94		-221
Balance at end of year	22,100		22,754		23,036
Deferred tax assets: Valuation allowance	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Balance at beginning of year	81,007		69,092		65,479
Additions - Charged to costs and expenses	16,488		9,570		18,665
Additions - Charged to other accounts	'		1,171		'
Deductions	6,710	[1]	7,347	[1]	4,651	[1]
Foreign currency translation	6,353		8,521		-10,401
Balance at end of year	¥ 97,138		¥ 81,007		¥ 69,092
[1]	Receivable: Bad debts written off, Deferred tax assets: Reversal of valuation allowance. Deductions in valuation allowance for the years ended March 31, 2012 and 2014 include a portion credited to other comprehensive income of ¥1,650 million and ¥1,173 million, respectively. Deductions in valuation allowance in the three-year period ended March 31, 2014 related to deferred tax assets that expired unused are immaterial.

Valuation_and_Qualifying_Accou3

Valuation and Qualifying Accounts (Parenthetical) (Detail) (Deferred tax assets: Reversal of valuation allowance, JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Deductions	¥ 6,710	[1]	¥ 7,347	[1]	¥ 4,651	[1]
Other Comprehensive Income	'		'		'
Valuation and Qualifying Accounts Disclosure [Line Items]	'		'		'
Deductions	¥ 1,173		'		¥ 1,650
[1]	Receivable: Bad debts written off, Deferred tax assets: Reversal of valuation allowance. Deductions in valuation allowance for the years ended March 31, 2012 and 2014 include a portion credited to other comprehensive income of ¥1,650 million and ¥1,173 million, respectively. Deductions in valuation allowance in the three-year period ended March 31, 2014 related to deferred tax assets that expired unused are immaterial.

Segment_Information_Additional

Segment Information - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2014
	Segment
Segment Reporting Disclosure [Line Items]	'
Number of reportable segments	4

Principal_Products_and_Service

Principal Products and Services, and Functions of Each Segment (Detail)	12 Months Ended
	Mar. 31, 2014
Motorcycle Business	'
Segment Reporting Disclosure [Line Items]	'
Principal products and services	'Motorcycles, all-terrain vehicles (ATVs) and relevant parts
Functions	'Research & Development, Manufacturing, Sales and related services
Automobile Business	'
Segment Reporting Disclosure [Line Items]	'
Principal products and services	'Automobiles and relevant parts
Functions	'Research & Development, Manufacturing, Sales and related services
Financial Services Business	'
Segment Reporting Disclosure [Line Items]	'
Principal products and services	'Financial, insurance services
Functions	'Retail loan and lease related to Honda products, Others
Power Product and Other Businesses	'
Segment Reporting Disclosure [Line Items]	'
Principal products and services	'Power products and relevant parts, and others
Functions	'Research & Development, Manufacturing, Sales and related services, Others

Segment_Information_Detail

Segment Information (Detail) (JPY ¥)

3 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

¥ 3,097,246

¥ 3,020,889

¥ 2,890,221

¥ 2,834,095

¥ 2,744,960

¥ 2,425,792

¥ 2,271,286

¥ 2,435,909

¥ 2,405,062

¥ 1,942,545

¥ 1,885,892

¥ 1,714,596

¥ 11,842,451

¥ 9,877,947

¥ 7,948,095

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

11,092,170

9,333,137

7,716,731

Segment income (loss)

165,293

228,574

171,451

184,963

135,989

131,941

100,867

176,013

111,976

44,298

52,511

22,579

750,281

544,810

231,364

Equity in income of affiliates

'

'

'

'

'

'

'

'

'

'

'

'

132,471

82,723

100,406

Segment assets

15,622,031

'

'

'

13,635,357

'

'

'

11,787,599

'

'

'

15,622,031

13,635,357

11,787,599

Investments in affiliates

562,664

'

'

'

457,376

'

'

'

430,783

'

'

'

562,664

457,376

430,783

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

794,720

590,469

554,867

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

1,909,867

1,423,526

1,108,180

Damaged and impairment losses on long-lived assets

'

'

'

'

'

'

'

'

'

'

'

'

3,301

4,773

12,104

Provision for credit and lease residual losses on finance subsidiaries- receivables

'

'

'

'

'

'

'

'

'

'

'

'

18,904

10,059

13,032

Motorcycle Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

1,663,631

1,339,549

1,348,828

Automobile Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

9,176,360

7,709,216

5,805,975

Financial Services Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

698,185

548,506

516,148

Power Product and Other Businesses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

304,275

280,676

277,144

Intersegment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-42,872

-37,118

-39,785

Intersegment | Automobile Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-18,569

-14,374

-16,767

Intersegment | Financial Services Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-10,403

-11,750

-10,428

Intersegment | Power Product and Other Businesses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-13,900

-10,994

-12,590

Operating Segments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

11,885,323

9,915,065

7,987,880

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

11,135,042

9,370,255

7,756,516

Segment income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

750,281

544,810

231,364

Equity in income of affiliates

'

'

'

'

'

'

'

'

'

'

'

'

132,471

82,723

100,406

Segment assets

15,990,649

'

'

'

13,928,954

'

'

'

11,912,090

'

'

'

15,990,649

13,928,954

11,912,090

Investments in affiliates

562,664

'

'

'

457,376

'

'

'

430,783

'

'

'

562,664

457,376

430,783

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

794,720

590,469

554,867

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

1,909,867

1,423,526

1,108,180

Damaged and impairment losses on long-lived assets

'

'

'

'

'

'

'

'

'

'

'

'

3,301

4,773

12,104

Provision for credit and lease residual losses on finance subsidiaries- receivables

'

'

'

'

'

'

'

'

'

'

'

'

18,904

10,059

13,032

Operating Segments | Motorcycle Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

1,663,631

1,339,549

1,348,828

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

1,498,026

1,229,316

1,206,226

Segment income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

165,605

110,233

142,602

Equity in income of affiliates

'

'

'

'

'

'

'

'

'

'

'

'

36,479

25,606

31,185

Segment assets

1,264,903

'

'

'

1,095,357

'

'

'

1,006,684

'

'

'

1,264,903

1,095,357

1,006,684

Investments in affiliates

102,359

'

'

'

85,039

'

'

'

70,275

'

'

'

102,359

85,039

70,275

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

46,038

34,665

43,564

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

57,702

73,513

62,075

Operating Segments | Automobile Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

9,194,929

7,723,590

5,822,742

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

8,791,228

7,437,599

5,899,948

Segment income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

403,701

285,991

-77,206

Equity in income of affiliates

'

'

'

'

'

'

'

'

'

'

'

'

94,506

56,361

68,521

Segment assets

6,398,580

'

'

'

5,759,126

'

'

'

4,955,791

'

'

'

6,398,580

5,759,126

4,955,791

Investments in affiliates

439,556

'

'

'

352,317

'

'

'

343,429

'

'

'

439,556

352,317

343,429

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

383,325

290,522

289,845

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

705,696

540,625

349,605

Damaged and impairment losses on long-lived assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

8,260

Operating Segments | Financial Services Business

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

708,588

560,256

526,576

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

525,832

402,098

356,570

Segment income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

182,756

158,158

170,006

Segment assets

7,980,989

'

'

'

6,765,322

'

'

'

5,644,380

'

'

'

7,980,989

6,765,322

5,644,380

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

354,704

256,166

211,325

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

1,131,761

794,869

686,495

Damaged and impairment losses on long-lived assets

'

'

'

'

'

'

'

'

'

'

'

'

3,301

4,773

1,514

Provision for credit and lease residual losses on finance subsidiaries- receivables

'

'

'

'

'

'

'

'

'

'

'

'

18,904

10,059

13,032

Operating Segments | Power Product and Other Businesses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

318,175

291,670

289,734

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

319,956

301,242

293,772

Segment income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

-1,781

-9,572

-4,038

Equity in income of affiliates

'

'

'

'

'

'

'

'

'

'

'

'

1,486

756

700

Segment assets

346,177

'

'

'

309,149

'

'

'

305,235

'

'

'

346,177

309,149

305,235

Investments in affiliates

20,749

'

'

'

20,020

'

'

'

17,079

'

'

'

20,749

20,020

17,079

Depreciation and amortization

'

'

'

'

'

'

'

'

'

'

'

'

10,653

9,116

10,133

Capital expenditures

'

'

'

'

'

'

'

'

'

'

'

'

14,708

14,519

10,005

Damaged and impairment losses on long-lived assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,330

Reconciling Items

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

-42,872

-37,118

-39,785

Segment assets

¥ (368,618)

'

'

'

¥ (293,597)

'

'

'

¥ (124,491)

'

'

'

¥ (368,618)

¥ (293,597)

¥ (124,491)

Segment_Information_Parentheti

Segment Information (Parenthetical) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]	'	'	'
Segment assets	¥ 15,622,031	¥ 13,635,357	¥ 11,787,599
Depreciation and amortization related to property on operating leases	352,402	254,933	209,762
Capital expenditures related to purchases of operating lease assets	1,127,840	793,118	683,767
Liabilities accrued for warranties issued	153,898	97,108	'
Depreciation expense decreased (increased)	-442,318	-335,536	-345,105
Change in depreciation method	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	56,300	'
Operating Segments	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	15,990,649	13,928,954	11,912,090
Operating Segments | Motorcycle Business	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	1,264,903	1,095,357	1,006,684
Operating Segments | Motorcycle Business | Change in depreciation method	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	6,358	'
Operating Segments | Automobile Business	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	6,398,580	5,759,126	4,955,791
Liabilities accrued for warranties issued	153,898	97,108	60,004
Operating Segments | Automobile Business | Change in depreciation method	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	48,568	'
Operating Segments | Financial Services Business	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	7,980,989	6,765,322	5,644,380
Depreciation and amortization related to property on operating leases	352,402	254,933	209,762
Capital expenditures related to purchases of operating lease assets	1,127,840	793,118	683,767
Operating Segments | Financial Services Business | Change in depreciation method	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	77	'
Operating Segments | Power Product and Other Businesses	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	346,177	309,149	305,235
Operating Segments | Power Product and Other Businesses | Change in depreciation method	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	1,297	'
Reconciling Items	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	-368,618	-293,597	-124,491
Unallocated amount	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment assets	¥ 294,819	¥ 293,583	¥ 399,732

External_Sales_and_Other_Opera

External Sales and Other Operating Revenue by Product or Service Groups (Detail) (JPY ¥)

3 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

¥ 3,097,246

¥ 3,020,889

¥ 2,890,221

¥ 2,834,095

¥ 2,744,960

¥ 2,425,792

¥ 2,271,286

¥ 2,435,909

¥ 2,405,062

¥ 1,942,545

¥ 1,885,892

¥ 1,714,596

¥ 11,842,451

¥ 9,877,947

¥ 7,948,095

Motorcycles and relevant parts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

1,582,901

1,274,890

1,286,319

All-terrain vehicles (ATVs) and relevant parts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

80,730

64,659

62,509

Automobiles and relevant parts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

9,176,360

7,709,216

5,805,975

Financial, insurance services

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

698,185

548,506

516,148

Power products and relevant parts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

251,630

221,321

208,661

Others

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenue from External Customer [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

External sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

¥ 52,645

¥ 59,355

¥ 68,483

Geographical_Information_Detai

Geographical Information (Detail) (JPY ¥)

3 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

¥ 3,097,246

¥ 3,020,889

¥ 2,890,221

¥ 2,834,095

¥ 2,744,960

¥ 2,425,792

¥ 2,271,286

¥ 2,435,909

¥ 2,405,062

¥ 1,942,545

¥ 1,885,892

¥ 1,714,596

¥ 11,842,451

¥ 9,877,947

¥ 7,948,095

Long-lived assets

5,198,069

'

'

'

4,350,818

'

'

'

3,534,908

'

'

'

5,198,069

4,350,818

3,534,908

Japan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

2,216,735

1,925,333

1,774,573

Long-lived assets

1,280,071

'

'

'

1,167,236

'

'

'

1,048,402

'

'

'

1,280,071

1,167,236

1,048,402

United States

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

4,934,018

4,063,727

3,099,810

Long-lived assets

2,783,977

'

'

'

2,380,885

'

'

'

1,889,567

'

'

'

2,783,977

2,380,885

1,889,567

Other Countries

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

4,691,698

3,888,887

3,073,712

Long-lived assets

¥ 1,134,021

'

'

'

¥ 802,697

'

'

'

¥ 596,939

'

'

'

¥ 1,134,021

¥ 802,697

¥ 596,939

Supplemental_Geographical_Info

Supplemental Geographical Information Based on Location of the Company and Its Subsidiaries (Detail) (JPY ¥)

3 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2012

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

¥ 3,097,246

¥ 3,020,889

¥ 2,890,221

¥ 2,834,095

¥ 2,744,960

¥ 2,425,792

¥ 2,271,286

¥ 2,435,909

¥ 2,405,062

¥ 1,942,545

¥ 1,885,892

¥ 1,714,596

¥ 11,842,451

¥ 9,877,947

¥ 7,948,095

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

11,092,170

9,333,137

7,716,731

Operating income (loss)

165,293

228,574

171,451

184,963

135,989

131,941

100,867

176,013

111,976

44,298

52,511

22,579

750,281

544,810

231,364

Assets

15,622,031

'

'

'

13,635,357

'

'

'

11,787,599

'

'

'

15,622,031

13,635,357

11,787,599

Long-lived assets

5,198,069

'

'

'

4,350,818

'

'

'

3,534,908

'

'

'

5,198,069

4,350,818

3,534,908

Japan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

2,216,735

1,925,333

1,774,573

Long-lived assets

1,280,071

'

'

'

1,167,236

'

'

'

1,048,402

'

'

'

1,280,071

1,167,236

1,048,402

North America

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

5,595,981

4,612,361

3,500,245

Europe

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

676,502

536,856

519,329

Asia

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

2,340,100

1,926,434

1,276,621

Other Regions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

1,013,133

876,963

877,327

Transfers between geographic areas

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-2,947,519

-2,716,891

-2,094,015

Transfers between geographic areas | Japan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-1,975,544

-1,968,179

-1,588,379

Transfers between geographic areas | North America

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-374,018

-244,741

-214,511

Transfers between geographic areas | Europe

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-98,766

-105,254

-61,463

Transfers between geographic areas | Asia

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-486,823

-379,213

-213,857

Transfers between geographic areas | Other Regions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

-12,368

-19,504

-15,805

Reportable Geographical Components

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

14,789,970

12,594,838

10,042,110

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

14,039,295

12,024,580

9,806,934

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

750,675

570,258

235,176

Assets

15,741,647

'

'

'

13,767,638

'

'

'

11,697,691

'

'

'

15,741,647

13,767,638

11,697,691

Long-lived assets

5,198,069

'

'

'

4,350,818

'

'

'

3,534,908

'

'

'

5,198,069

4,350,818

3,534,908

Reportable Geographical Components | Japan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

4,192,279

3,893,512

3,362,952

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

3,978,185

3,715,084

3,472,786

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

214,094

178,428

-109,834

Assets

3,442,746

'

'

'

3,264,383

'

'

'

3,112,901

'

'

'

3,442,746

3,264,383

3,112,901

Long-lived assets

1,280,071

'

'

'

1,167,236

'

'

'

1,048,402

'

'

'

1,280,071

1,167,236

1,048,402

Reportable Geographical Components | North America

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

5,969,999

4,857,102

3,714,756

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

5,679,094

4,648,184

3,491,463

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

290,905

208,918

223,293

Assets

8,825,278

'

'

'

7,645,540

'

'

'

6,333,851

'

'

'

8,825,278

7,645,540

6,333,851

Long-lived assets

3,025,095

'

'

'

2,481,097

'

'

'

1,970,631

'

'

'

3,025,095

2,481,097

1,970,631

Reportable Geographical Components | Europe

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

775,268

642,110

580,792

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

792,393

641,650

592,901

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

-17,125

460

-12,109

Assets

709,469

'

'

'

673,667

'

'

'

568,790

'

'

'

709,469

673,667

568,790

Long-lived assets

133,061

'

'

'

124,088

'

'

'

111,354

'

'

'

133,061

124,088

111,354

Reportable Geographical Components | Asia

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

2,826,923

2,305,647

1,490,478

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

2,609,023

2,158,889

1,413,608

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

217,900

146,758

76,870

Assets

1,996,929

'

'

'

1,523,192

'

'

'

1,070,331

'

'

'

1,996,929

1,523,192

1,070,331

Long-lived assets

588,413

'

'

'

434,827

'

'

'

274,182

'

'

'

588,413

434,827

274,182

Reportable Geographical Components | Other Regions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net sales and other operating revenue

'

'

'

'

'

'

'

'

'

'

'

'

1,025,501

896,467

893,132

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

980,600

860,773

836,176

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

44,901

35,694

56,956

Assets

767,225

'

'

'

660,856

'

'

'

611,818

'

'

'

767,225

660,856

611,818

Long-lived assets

171,429

'

'

'

143,570

'

'

'

130,339

'

'

'

171,429

143,570

130,339

Reconciling Items

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost of sales, SG&A and R&D expenses

'

'

'

'

'

'

'

'

'

'

'

'

-2,947,125

-2,691,443

-2,090,203

Operating income (loss)

'

'

'

'

'

'

'

'

'

'

'

'

-394

-25,448

-3,812

Assets

¥ (119,616)

'

'

'

¥ (132,281)

'

'

'

¥ 89,908

'

'

'

¥ (119,616)

¥ (132,281)

¥ 89,908

Supplemental_Geographical_Info1

Supplemental Geographical Information Based on Location of the Company and Its Subsidiaries (Parenthetical) (Detail) (JPY ¥)	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	¥ 15,622,031	¥ 13,635,357	¥ 11,787,599
Depreciation expense decreased (increased)	-442,318	-335,536	-345,105
Change in depreciation method	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	56,300	'
Reportable Geographical Components	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	15,741,647	13,767,638	11,697,691
Reportable Geographical Components | Japan	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	3,442,746	3,264,383	3,112,901
Reportable Geographical Components | Japan | Change in depreciation method	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	42,486	'
Reportable Geographical Components | North America	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	8,825,278	7,645,540	6,333,851
Reportable Geographical Components | North America | Change in depreciation method	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	9,602	'
Reportable Geographical Components | Europe	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	709,469	673,667	568,790
Reportable Geographical Components | Europe | Change in depreciation method	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	1,068	'
Reportable Geographical Components | Asia	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	1,996,929	1,523,192	1,070,331
Reportable Geographical Components | Asia | Change in depreciation method	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Depreciation expense decreased (increased)	'	3,144	'
Reconciling Items	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	-119,616	-132,281	89,908
Unallocated amount	'	'	'
Segment Reporting Disclosure [Line Items]	'	'	'
Assets	¥ 294,819	¥ 293,583	¥ 399,732

Quarterly_Financial_Data_Detai

Quarterly Financial Data (Detail) (JPY ¥)	3 Months Ended												12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Quarterly Financial Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'	'	'	'	'
Net sales and other operating revenue	¥ 3,097,246	¥ 3,020,889	¥ 2,890,221	¥ 2,834,095	¥ 2,744,960	¥ 2,425,792	¥ 2,271,286	¥ 2,435,909	¥ 2,405,062	¥ 1,942,545	¥ 1,885,892	¥ 1,714,596	¥ 11,842,451	¥ 9,877,947	¥ 7,948,095
Operating income (loss)	165,293	228,574	171,451	184,963	135,989	131,941	100,867	176,013	111,976	44,298	52,511	22,579	750,281	544,810	231,364
Net income (loss) attributable to Honda Motor Co., Ltd.	¥ 170,508	¥ 160,732	¥ 120,368	¥ 122,499	¥ 75,752	¥ 77,441	¥ 82,233	¥ 131,723	¥ 71,594	¥ 47,662	¥ 60,429	¥ 31,797	¥ 574,107	¥ 367,149	¥ 211,482
Basic net income (loss) attributable to Honda Motor Co., Ltd. per common share (in yen per share)	¥ 94.61	¥ 89.18	¥ 66.79	¥ 67.97	¥ 42.03	¥ 42.97	¥ 45.63	¥ 73.09	¥ 39.72	¥ 26.45	¥ 33.53	¥ 17.64	¥ 318.54	¥ 203.71	¥ 117.34