CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 30,444	$ 20,863	$ 76,259	$ 79,089
Other comprehensive loss, net of tax:
Foreign currency translation	(6,692)	1,111	(3,612)	(5,534)
Net change with respect to derivative instruments and hedging activities, net of tax of $56, $(33), $(34), and $243	(195)		133
Net change with respect to derivative instruments and hedging activities, net of tax of $56, $(33), $(34), and $243		131		(896)
Net change in pension and postretirement obligation adjustments, net of tax of $(232), $(79), $(323), and $(221)	777	270	1,207	769
Attributable to unconsolidated affiliates, net of tax of $(159), $2,005, $(240), and $2,086	547	(6,907)	828	(7,187)
Total other comprehensive loss, net	(5,563)	(5,395)	(1,444)	(12,848)
Consolidated comprehensive income	24,881	15,468	74,815	66,241
Comprehensive income attributable to noncontrolling interests	(857)	(34)	(2,044)	(1,097)
Comprehensive income attributable to Mueller Industries, Inc.	$ 24,024	$ 15,434	$ 72,771	$ 65,144