CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 27, 2025	Dec. 28, 2024	Dec. 30, 2023
Income Statement [Abstract]
Net sales	$ 4,178,547	$ 3,768,766	$ 3,420,345
Cost of goods sold	2,966,083	2,724,328	2,433,511
Depreciation and amortization	68,561	53,133	39,954
Selling, general, and administrative expense	248,651	226,696	208,172
Gain on sale of businesses	0	0	(4,137)
Gain on disposal of assets, net	(25,878)	(5,780)	0
Impairment charges	3,735	0	6,258
Gain on insurance proceeds	(41,147)	0	(19,466)
Operating income	958,542	770,389	756,053
Interest expense	(108)	(410)	(1,221)
Interest income	41,068	53,468	38,208
Realized and unrealized gains on short-term investments	18,547	914	41,865
Gain on extinguishment of NMTC liability	0	1,265	7,534
Environmental expense	(2,151)	(2,218)	(825)
Pension plan termination expense	(4,830)	0	0
Other income (expense), net	1,294	(2,946)	3,618
Income before income taxes	1,012,362	820,462	845,232
Income tax expense	(247,351)	(205,076)	(220,762)
Income (loss) from unconsolidated affiliates, net of foreign tax	8,579	2,156	(14,821)
Consolidated net income	773,590	617,542	609,649
Net income attributable to noncontrolling interests	(8,399)	(12,663)	(6,752)
Net income attributable to Mueller Industries, Inc.	$ 765,191	$ 604,879	$ 602,897
Weighted average shares for basic earnings per share (in shares)	109,475	111,385	111,420
Effect of dilutive stock-based awards (in shares)	2,017	2,580	2,242
Adjusted weighted average shares for diluted earnings per share (in shares)	111,492	113,965	113,662
Basic earnings per share (in dollars per share)	$ 6.99	$ 5.43	$ 5.41
Diluted earnings per share (in dollars per share)	6.86	5.31	5.30
Dividends per share (in dollars per share)	$ 1.00	$ 0.80	$ 0.60