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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 3) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2015	Jun. 27, 2015	Dec. 27, 2014
Level 1 member
Assets and liabilities measured at fair value
Trading Securities		$ 44,755	$ 45,473
Carrying Value
Assets and liabilities measured at fair value
Trading Securities		44,755	45,473
EMD
Assets and liabilities measured at fair value
Fair value of remaining ownership		4,966	9,034
Special dividend	$ 5,010
Valmont Deferred Compensation Plan
Assets and liabilities measured at fair value
Assets recorded for the investments held		$ 39,789	$ 36,439