Related Party Transactions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Mar. 31, 2012
Related Party Transaction [Line Items]
Accounts receivable	$ 110,357	$ 71,392	$ 32,316
Accounts payable	27,602	31,386	37,520
Purchases	26,319	30,725
Zimbabwe subsidiary [Member]
Related Party Transaction [Line Items]
Accounts receivable		$ 32,094

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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+ Details

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

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+ Details