Goodwill and Other Intangible Assets (Schedule of Acquired Finite Lived Intangible Assets) (Details) (JPY ¥) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010
Gross carrying amount	¥ 913,416	¥ 895,180
Accumulated amortization	373,762	295,747
Patents and Know-how [Member]
Gross carrying amount	451,868	439,608
Accumulated amortization	97,450	54,684
Average amortization period, in years	11
Computer Software, Intangible Asset [Member]
Gross carrying amount	298,328	283,075
Accumulated amortization	229,132	210,726
Average amortization period, in years	4
Other [Member]
Gross carrying amount	163,220	172,497
Accumulated amortization	¥ 47,180	¥ 30,337
Average amortization period, in years	14

The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(1)

+ Details

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- Definition

The average useful life of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar either by their nature or by their use in the operations of a company.

+ Details

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- Definition

Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(1)

+ Details

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