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Derivative Financial Instruments (Details) € in Thousands, lb in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) swap lb	Mar. 31, 2015 USD ($) lb	Mar. 31, 2014 USD ($)	Dec. 31, 2015 EUR (€) swap	Mar. 31, 2015 EUR (€)
Derivative [Line Items]
Derivative, notional amount	$ 400,000,000
Fair value of derivative instruments designated as hedging instruments
Fair value of derivative assets designated as hedging instruments	3,979,000	$ 7,823,000
Fair value of derivative liabilities designated as hedging instruments	8,353,000	11,137,000
Gain (Loss) Reclassified from AOCI
Commodity forward contracts, (gain) loss reclassified from AOCI	(2,825,000)	(5,515,000)
Interest rate swap contracts, (gain) loss reclassified from AOCI	(3,028,000)	(4,020,000)
Forward foreign currency contracts, (gain) loss reclassified from AOCI	(1,768,000)	(9,182,000)
Gain (Loss) Recognized in Income (ineffective portion and amount excluded from effectiveness testing)
Commodity forward contracts, gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0	0	$ 0
Interest rate swap contracts, gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0	0
Forward foreign currency contracts, gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	0	0
Other current assets
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of assets	0	1,054,000
Foreign currency forward contracts designated as hedging instruments, fair value of assets	2,875,000	2,664,000
Interest rate swap contracts designated as hedging instruments, fair value of assets	9,000	0
Other current liabilities
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of liabilities	4,445,000	899,000
Foreign currency forward contracts designated as hedging instruments, fair value of liabilities	1,442,000	5,101,000
Interest rate swap contracts designated as hedging instruments, fair value of liability	0	0
Other noncurrent assets
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of assets	0	271,000
Foreign currency forward contracts designated as hedging instruments, fair value of assets	1,095,000	3,834,000
Interest rate swap contracts designated as hedging instruments, fair value of assets	0	0
Other noncurrent liabilities
Fair value of derivative instruments designated as hedging instruments
Commodity forward contracts designated as hedging instruments, fair value of liabilities	0	2,000
Foreign currency forward contracts designated as hedging instruments, fair value of liabilities	18,000	897,000
Interest rate swap contracts designated as hedging instruments, fair value of liability	$ 2,448,000	$ 4,238,000
Copper
Derivative [Line Items]
Commodity derivatives (mass) \| lb	7,750	16,475
Zinc
Derivative [Line Items]
Commodity derivatives (mass) \| lb	1,750	4,840
Foreign Exchange Forward \| Euros Sold
Derivative [Line Items]
Derivative, notional amount \| €				€ 67,780	€ 98,580
Foreign Exchange Forward \| Euros Purchased
Derivative [Line Items]
Derivative, notional amount \| €				€ 12,589	€ 33,354
Number of interest rate derivatives held in liability position [Member]
Derivative [Line Items]
Number of interest rate derivatives held \| swap	4			4