Commitments, Contingent Liabilities and Other (Changes in Product Warranty Liability) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the fiscal year	¥ 60,798	¥ 66,943	¥ 75,129
Additional liabilities for warranties	34,557	53,502	83,227
Settlements (in cash or in kind)	(32,549)	(49,532)	(81,462)
Changes in estimate for pre-existing warranty reserve	(16,888)	(7,927)	(6,440)
Translation adjustment	2,234	(2,188)	(3,511)
Balance at end of the fiscal year	¥ 48,152	¥ 60,798	¥ 66,943

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

+ Details

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- Definition

Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

+ References

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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.

+ References

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