Foreign Currency Exchange Rate, Translation

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- Definition

Maximum Lag Period of Recognizing the Results of Subsidiaries and Affiliates

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- Definition

Significant Accounting Policies [Line Items]

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- Definition

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 5
-Subparagraph c

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 14
-Article 5

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- Definition

Aggregate adjustment to additional paid in capital for stock to account for a stock split in the case where the per-share par value or stated value is not reduced or increased proportionately such that the total par value or stated value remains the same for all shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 31
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-7

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 6
-Subparagraph a
-Article 5

+ Details

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- Definition

Cost of real estate projects incurred for projects for eventual sale or transfer (condominium or time share projects, vacation clubs).

+ Details

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- Definition

Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 4
-Section 7
-Paragraph 14

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Concepts (CON)
-Number 6
-Paragraph 86

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- Definition

Describes the policy as to when a loan ceases to accrue interest or other revenue because the borrower is in financial difficulty. May also describe the treatment of previously earned but uncollected interest income on loans in nonaccrual status, how cash received from borrowers is recorded on loans that are in nonaccrual status, and the policy for resuming accrual of interest. Also includes the policy for charging off uncollectible loans and trade receivables, and the policy for determining past-due or delinquency status (i.e. whether past-due status is based on how recently payments have been received or on contractual terms).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 01-6
-Paragraph 13
-Subparagraph c, g

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 114
-Paragraph 8, 11, 12, 13, 14, 15, 17, 20

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- Definition

This element describes an entity's accounting policy for investments in debt and equity securities that are classified as available-for-sale. These policies also may describe the entity's accounting treatment for transfers between investment categories, how the entity determines whether impairments of available-for-sale securities are other than temporary, and how the fair values of such securities are determined.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 7, 8, 9, 13, 14, 15, 16, 17

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 12, 13, 14, 15, 16

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section M

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10, 11

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 2, 12
-Article 5

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- Definition

Amount of the cumulative effect of the change in accounting principle on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 154
-Paragraph 2, 17, 18

+ Details

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- Definition

The average useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land and improvements, buildings, and production equipment.

+ Details

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- Definition

The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land and improvements, buildings, and production equipment.

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- Definition

The amount of interest capitalized to an operative builder's inventory during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21

+ Details

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Significant Accounting and Reporting Policies - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)	Mar. 31, 2011 Other Operating Assets USD ($)	Mar. 31, 2011 Other Operating Assets JPY (¥)	Mar. 31, 2010 Other Operating Assets JPY (¥)	Mar. 31, 2009 Other Operating Assets JPY (¥)	Mar. 31, 2011 Other Operating Assets Property, Plant and Equipment, Other Types Year	Mar. 31, 2011 Other Operating Assets Buildings Year	Mar. 31, 2011 Other Operating Assets Land improvement Year	Mar. 31, 2011 Office Facilities USD ($)	Mar. 31, 2011 Office Facilities JPY (¥)	Mar. 31, 2010 Office Facilities JPY (¥)	Mar. 31, 2009 Office Facilities JPY (¥)	Mar. 31, 2011 Office Facilities Buildings and fixtures Year	Mar. 31, 2011 Office Facilities Machinery and equipment Year	Mar. 31, 2011 Investment in operating leases Transportation equipment Year	Mar. 31, 2011 Investment in operating leases Measuring and information-related equipment Year	Mar. 31, 2011 Investment in operating leases Real Estate Year	Mar. 31, 2011 Investment in operating leases Property, Plant and Equipment, Other Types Year	Mar. 31, 2011 Adjustments for New Accounting Pronouncement Assets JPY (¥)	Mar. 31, 2011 Adjustments for New Accounting Pronouncement Liabilities JPY (¥)	Mar. 31, 2011 Adjustments for New Accounting Pronouncement Retained Earnings JPY (¥)
Significant Accounting Policies [Line Items]
A maximum lag period of recognizing the results of subsidiaries and affiliates	3M	3M
Revenues on direct financing leases and installment loans past due policy	The Company and its subsidiaries suspend accruing revenues on past-due installment loans and direct financing leases when principal or interest is past-due 90 days or more, or earlier, if management determines that their collections are doubtful based on factors such as individual debtors’ creditworthiness, historical loss experience, current delinquencies and delinquency trends.	The Company and its subsidiaries suspend accruing revenues on past-due installment loans and direct financing leases when principal or interest is past-due 90 days or more, or earlier, if management determines that their collections are doubtful based on factors such as individual debtors’ creditworthiness, historical loss experience, current delinquencies and delinquency trends.
Available-for-sale securities, recognition of losses related to equity securities policy	For available-for-sale securities, the Company and its subsidiaries generally recognize losses related to equity securities for which the fair value has been significantly below the acquisition cost (or current carrying value if an adjustment has been made in the past) for more than six months.	For available-for-sale securities, the Company and its subsidiaries generally recognize losses related to equity securities for which the fair value has been significantly below the acquisition cost (or current carrying value if an adjustment has been made in the past) for more than six months.
Increase in additional paid-in capital had such stock splits made prior to October 1, 2001	$ 297,000,000	¥ 24,674,000,000
Write-down of advance and/or progress payments for development of residential condominiums	118,000,000	9,844,000,000	7,115,000,000	10,911,000,000
Capitalized interest costs related to specific long-term development projects	44,000,000	3,646,000,000	2,810,000,000	2,766,000,000
Advertising expense	74,000,000	6,165,000,000	6,870,000,000	11,280,000,000
Estimated average useful lives																		8	4	33	7
Depreciation expenses					94,000,000	7,849,000,000	7,202,000,000	6,717,000,000				35,000,000	2,906,000,000	3,153,000,000	3,613,000,000
Accumulated depreciation					418,000,000	34,739,000,000	31,650,000,000					470,000,000	39,057,000,000	37,319,000,000
Estimated useful lives, maximum									20	50	60					62	20
Advance and/or progress payments for development of condominiums for sale	1,157,000,000	96,197,000,000	115,285,000,000
Finished goods	147,000,000	12,213,000,000	37,971,000,000
Translations of Japanese yen into U.S. dollars, prevailing exchange rate	83.15	83.15
Cumulative effect of adopting new accounting pronouncements																						¥ 1,147,000,000,000	¥ 1,169,000,000,000	¥ (22,000,000,000)