Accumulated Other Comprehensive Income - Reclassification Adjustments Out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	$ 524,311	$ 456,060	$ 1,012,738	$ 902,702
Interest expense	6,442	1,692	8,973	3,540
Income tax (benefit) expense	12,650	14,005	24,579	28,126
Selling, general, and administrative expense	34,557	34,514	70,088	70,294
Other income, net	(231)	(515)	(782)	(760)
Net income attributable to Mueller Industries, Inc.	(27,633)	(27,797)	(57,620)	(56,427)
Unrealized losses (gains) on derivatives attributable to parent [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	602	(2,108)	1,024	(1,871)
Interest expense	232	92	464	200
Income tax (benefit) expense	(361)	716	(514)	508
Net income attributable to Mueller Industries, Inc.	473	(1,300)	974	(1,163)
Amortization of net loss and prior service cost on employee benefit plans attributable to parent [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (benefit) expense	(46)	(122)	(110)	(262)
Selling, general, and administrative expense	275	502	601	1,054
Net income attributable to Mueller Industries, Inc.	229	380	491	792
Sale of available-for-sale securities attributable to parent [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (benefit) expense	138	0	232	0
Other income, net	(357)	0	(611)	0
Net income attributable to Mueller Industries, Inc.	(219)	0	(379)	0
Gain recognized upon sale of business attributable to parent [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (benefit) expense	0	0	0	0
Selling, general, and administrative expense	(3,777)	0	(3,777)	0
Net income attributable to Mueller Industries, Inc.	$ (3,777)	$ 0	$ (3,777)	$ 0