Increase decrease in policy liability and policy account balances.

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- Definition

Increase decrease in policy liability discount rate

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No definition available.

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- Definition

Increase (decrease) in retained earnings.

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No definition available.

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- Definition

Maximum Lag Period of Recognizing the Results of Subsidiaries and Affiliates

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No definition available.

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- Definition

Percentage Of Tax Benefit Realized Upon Ultimate Settlement With Taxing Authority

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No definition available.

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- Definition

Significant Accounting Policies [Line Items]

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No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 360
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- Definition

The increase (decrease) in life insurance liability balances during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Amount of increase (decrease) in operating assets classified as other.

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6)(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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).

+ References

No definition available.

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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Significant Accounting and Reporting Policies - Additional Information (Detail) - JPY (¥) ¥ in Millions		12 Months Ended
	Apr. 01, 2021	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Significant Accounting Policies [Line Items]
A maximum lag period of recognizing the results of subsidiaries and affiliates		3 months
Residential condominiums under development		¥ 74,621	¥ 62,414
Completed residential condominiums and merchandise for sale		94,400	77,149
Write-downs on completed residential condominiums and merchandise for sale		1,205	10,492	¥ 2,510
Accounting Standards Update 2018-12
Significant Accounting Policies [Line Items]
Increase (decrease) in policy liability and policy account balances	¥ 29,000	(234,000)	(51,000)
Increase (decrease) in policy liability discount rate	¥ (25,000)	165,000	38,000
Increase (decrease) in other operating assets		24,000	10,000
Increase (decrease) in life insurance costs		(25,000)	(5,000)
Accounting Standards Update 2018-12 \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Significant Accounting Policies [Line Items]
Increase (decrease) in retained earnings		¥ 23,000	6,000
Investment in operating leases \| Transportation equipment
Significant Accounting Policies [Line Items]
Estimated average useful lives		5 years
Investment in operating leases \| Measuring and information-related equipment
Significant Accounting Policies [Line Items]
Estimated average useful lives		4 years
Investment in operating leases \| Real Estate Other Than Land
Significant Accounting Policies [Line Items]
Estimated average useful lives		31 years
Investment in operating leases \| Other
Significant Accounting Policies [Line Items]
Estimated average useful lives		8 years
Property under Facility Operations
Significant Accounting Policies [Line Items]
Depreciation expenses		¥ 34,622	29,871	30,448
Accumulated depreciation		180,130	147,459
Office Facilities
Significant Accounting Policies [Line Items]
Depreciation expenses		8,373	9,083	¥ 8,269
Accumulated depreciation		¥ 74,507	¥ 73,063
Minimum
Significant Accounting Policies [Line Items]
Income tax settlement by tax authority		50.00%
Maximum \| Property under Facility Operations \| Buildings
Significant Accounting Policies [Line Items]
Estimated average useful lives		50 years
Maximum \| Property under Facility Operations \| Structures
Significant Accounting Policies [Line Items]
Estimated average useful lives		60 years
Maximum \| Property under Facility Operations \| Property, Plant and Equipment, Other Types
Significant Accounting Policies [Line Items]
Estimated average useful lives		44 years
Maximum \| Office Facilities \| Buildings And Structures
Significant Accounting Policies [Line Items]
Estimated average useful lives		62 years
Maximum \| Office Facilities \| Machinery and equipment
Significant Accounting Policies [Line Items]
Estimated average useful lives		46 years