CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	[1]	Jun. 30, 2018		Jul. 01, 2017
Income Statement [Abstract]
Net sales	$ 662,773	$ 614,266		$ 1,302,833		$ 1,192,186	[1]
Cost of goods sold	563,820	524,311		1,109,490		1,012,738	[1]
Depreciation and amortization	9,006	8,595		18,462		16,950	[1]
Selling, general, and administrative expense	38,428	36,299		72,485		71,873	[1]
(Gain) loss on sale of assets	(409)	(1,631)		3,060		(1,631)
Operating income	51,928	46,692		99,336		92,256	[1]
Interest expense	(6,073)	(6,442)		(11,982)		(8,973)	[1]
Other income, net	586	342		1,146		936	[1]
Income before income taxes	46,441	40,592		88,500		84,219	[1]
Income tax expense	(12,411)	(12,650)		(19,806)		(24,579)	[1]
Loss from unconsolidated affiliates, net of foreign tax	(148)	(109)		(10,468)		(1,352)	[1],[2]
Consolidated net income	33,882	27,833		58,226	[1]	58,288	[1],[2]
Net income attributable to noncontrolling interests	(700)	(200)		(916)		(668)	[1]
Net income attributable to Mueller Industries, Inc.	$ 33,182	$ 27,633		$ 57,310		$ 57,620	[1]
Weighted average shares for basic earnings per share (in shares)	56,797	56,906		56,848		56,843	[1]
Effect of dilutive stock-based awards (in shares)	514	511		516		585	[1]
Adjusted weighted average shares for diluted earnings per share (in shares)	57,311	57,417		57,364		57,428	[1]
Basic earnings per share (in dollars per share)	$ 0.58	$ 0.49		$ 1.01		$ 1.01	[1]
Diluted earnings per share (in dollars per share)	0.58	0.48		1.00		1.00	[1]
Dividends per share (in dollars per share)	$ 0.1	$ 0.1		$ 0.2		$ 8.2	[1]

[1] The Condensed Consolidated Statements of Income for the quarter and six months ended July 1, 2017 have been adjusted to reflect the adoption of ASU 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. The components of net periodic benefit cost (income) other than the service cost component are included in other income, net in the Condensed Consolidated Statements of Income. Refer to Note 1 for further discussion.

[2] The Condensed Consolidated Statement of Cash Flows for the six months ended July 1, 2017 has been adjusted to reflect the adoption of ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. The Condensed Consolidated Statements of Cash Flows reflects the changes during the periods in the total of cash, cash equivalents, and restricted cash. Therefore, restricted cash activity is included with cash when reconciling the beginning-of-period and end-of-period total amounts shown. Refer to Note 1 for further discussion.