Goodwill and Other Intangible Assets (Narrative) (Details) (JPY ¥) In Millions	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Goodwill and Other Intangible Assets
Aggregate amortization for finite-lived intangible assets	¥ 82,762	¥ 46,175	¥ 38,903

Aggregate amount of amortization expense recognized for intangible asset during the period. A recognized intangible asset shall be amortized over its estimated useful life to the reporting entity unless that life is determined to be indefinite. If an intangible asset has a finite useful life, but the precise length of that life is not known, that intangible asset shall be amortized over the best estimate of its useful life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(2)

Name:	us-gaap_FiniteLivedIntangibleAssetsAmortizationExpense
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration