Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $) In Thousands	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Consolidated Statements of Changes in Shareholders' Equity
Actuarial gain (loss) on pension plan, tax	$ 241	$ 122	$ 182

Tax effects of the net changes to accumulated comprehensive income during the period related to benefit plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 25

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Period Type:	duration