Lease Commitments (Details) (USD $)	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Future minimum lease commitments under operating leases [Abstract]
2012	$ 8,785,000
2013	7,074,000
2014	4,704,000
2015	3,353,000
2016	2,954,000
Thereafter	3,986,000
Total minimum payments	30,856,000
Rental expense under operating lease	$ 9,800,000	$ 8,200,000	$ 7,900,000

Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 15

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 16
-Subparagraph c

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Period Type:	duration

- Definition

The total of future contractually required payments on leases defined as operating.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 122

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 13
-Paragraph 16
-Subparagraph b(i)

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the third year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

+ References

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fifth year from the balance sheet date on leases defined as operating.

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