Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

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Derivative Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jan. 01, 2012	Jan. 02, 2011	Jan. 01, 2012	Jan. 02, 2011	Mar. 31, 2011
Fair value of derivative instruments designated as hedging instruments
Fair value of derivative assets designated as hedging instruments	$ 9,791		$ 9,791		$ 49,407
Fair value of derivative liabilities designated as hedging instruments	12,934		12,934
Pretax amount of gain (loss) recognized in Other Comprehensive Income (Loss)
Commodity forward contracts, (gain) / loss recognized in other comprehensive income (loss)	(3,143)	64,585	(3,143)	64,585
Foreign currency forward contracts, (gain) / loss recognized in other comprehensive income (loss)		75		75
Pretax amount of gain (loss) reclassified from Accumulated Other Comprehensive Income (Loss)
Commodity forward contracts, (gain)/loss reclassified from accumulated other comprehensive income (loss)	2,908	12,747	22,138	29,552
Other current assets / other accrued liabilities
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of assets	7,967		7,967		36,398
Foreign currency forward contracts designated as hedging instruments, fair value of assets					390
Commodity forward contracts designated as hedging instruments, fair value of liabilities	12,686		12,686
Deferred charges and other non-current assets / other long-term liabilities
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of assets	1,824		1,824		12,619
Commodity forward contracts designated as hedging instruments, fair value of liabilities	$ 248		$ 248
Copper
Derivative Financial Instruments
Outstanding commodity forward contracts, quantity hedged (in pounds)	25,750,000		25,750,000
Zinc
Derivative Financial Instruments
Outstanding commodity forward contracts, quantity hedged (in pounds)	8,595,000		8,595,000