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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 5) (USD $)	0 Months Ended	12 Months Ended			1 Months Ended	3 Months Ended
	May 13, 2014	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012	Mar. 02, 2013	Mar. 30, 2013	Feb. 28, 2015
Equity Method Investments
Amount recognized in currency translation adjustments previously recorded as part of accumulated other comprehensive income			$ (5,194,000)
Research and Development
Research and development expenses		13,900,000us-gaap_ResearchAndDevelopmentExpense	10,200,000us-gaap_ResearchAndDevelopmentExpense	7,100,000us-gaap_ResearchAndDevelopmentExpense
Stock Repurchase Program
Authorized amount	500,000,000						250,000,000
Length of authorization period	12 months
Number of shares acquired		2,711,149us-gaap_TreasuryStockSharesAcquired
Amount paid for share repurchase		395,045,000
Manganese Materials Company Pty. Ltd.
Equity Method Investments
Proceeds from sale of business					29,250,000
Amount recognized in currency translation adjustments previously recorded as part of accumulated other comprehensive income					5,194,000
Deferred tax benefits associated with sale of business						$ 3,200,000