SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 5) - USD ($)		1 Months Ended	12 Months Ended			19 Months Ended
	May. 13, 2014	May. 31, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Dec. 26, 2015	Feb. 28, 2015	Feb. 24, 2015
Equity Method Investments
Amount recognized in currency translation adjustments previously recorded as part of accumulated other comprehensive income			$ 0	$ 0	$ (5,194,000)
Research and Development
Research and development expenses			$ 11,600,000	$ 13,900,000	10,200,000
Stock Repurchase Program
Authorized amount	$ 500,000,000	$ 500,000,000					$ 250,000,000	$ 250,000,000
Length of authorization period	12 months	12 months
Shares acquired under share repurchase program			1,435,488	2,711,149		4,146,637
Amount paid for share repurchase			$ 168,983,000	$ 395,045,000	0	$ 564,000,000
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