Fair Value Measurements (Assets and Liabilities Remeasured At Fair Value on a Nonrecurring Basis) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Nonrecurring changes in fair value, Amounts included in earnings	¥ (22,656)	¥ (49,242)
Fair Value, Measurements, Nonrecurring \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Remeasurement of retained investment in SRE	15,911
Long-lived assets, Estimated fair value	0
Fair Value, Measurements, Nonrecurring \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-lived assets, Estimated fair value	0
Fair Value, Measurements, Nonrecurring \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-lived assets, Estimated fair value	8,155	4,389
Goodwill, Estimated fair value		0
Long-lived assets impairments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Nonrecurring changes in fair value, Amounts included in earnings	(36,003)	(44,135)
Goodwill impairments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Nonrecurring changes in fair value, Amounts included in earnings		¥ (5,107)
Remeasurement Of Retained Investment in SRE [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Nonrecurring changes in fair value, Amounts included in earnings	¥ 13,347

Amount of gains or losses recorded as a results of nonrecurring changes in fair value.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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