FINANCIAL INSTRUMENTS (Details) (USD $) In Thousands	Sep. 30, 2011	Mar. 31, 2011
Fair value of assets and liabilities
Other current assets	$ 56,715	$ 55,691
TOTAL ASSETS	1,179,733	1,306,625
Other liabilities	7,109	7,478
Fair value measurements on recurring basis | Level 1
Fair value of assets and liabilities
Other current assets	11,228
TOTAL ASSETS	11,228
Other current liabilities	11,228
Total liabilities	11,228
Fair value measurements on recurring basis | Level 2
Fair value of assets and liabilities
Other liabilities	1,192
Total liabilities	1,192
Fair value measurements on recurring basis | Total Fair Value
Fair value of assets and liabilities
Other current assets	11,228
TOTAL ASSETS	11,228
Other current liabilities	11,228
Other liabilities	1,192
Total liabilities	$ 12,420