Mueller Industries (MLI) 10-Q 25 Oct 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 20, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	MUELLER INDUSTRIES INC
Entity Central Index Key	89,439
Current Fiscal Year End Date	--12-30
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		57,805,254

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Income Statement [Abstract]
Net sales	$ 550,363	$ 506,584	$ 1,742,549	$ 1,583,464
Cost of goods sold	471,262	424,668	1,484,000	1,327,370
Depreciation and amortization	8,266	9,016	25,216	26,997
Selling, general, and administrative expense	33,276	32,413	102,953	102,707
Asset impairments	0	3,000	411	3,000
Operating income	37,559	37,487	129,969	123,390
Interest expense	(5,237)	(1,830)	(14,210)	(5,370)
Other (expense) income, net	(458)	120	324	880
Income before income taxes	31,864	35,777	116,083	118,900
Income tax expense	(8,716)	(10,837)	(33,295)	(38,963)
(Loss) income from unconsolidated affiliates, net of tax	(394)	1,122	(1,746)	3,049
Consolidated net income	22,754	26,062	81,042	82,986
Net income attributable to noncontrolling interests	(496)	(84)	(1,164)	(581)
Net income attributable to Mueller Industries, Inc.	$ 22,258	$ 25,978	$ 79,878	$ 82,405
Weighted average shares for basic earnings per share (in shares)	56,987	56,631	56,891	56,536
Effect of dilutive stock-based awards (in shares)	456	586	542	589
Adjusted weighted average shares for diluted earnings per share (in shares)	57,443	57,217	57,433	57,125
Basic earnings per share (in dollars per share)	$ 0.39	$ 0.46	$ 1.40	$ 1.46
Diluted earnings per share (in dollars per share)	0.39	0.45	1.39	1.44
Dividends per share (in dollars per share)	$ 0.1	$ 0.1	$ 8.300	$ 0.275

CONDENSED CONSOLIDATED STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 22,754	$ 26,062	$ 81,042	$ 82,986
Other comprehensive income (loss), net of tax:
Foreign currency translation	7,154	(4,304)	15,270	(15,601)
Net change with respect to derivative instruments and hedging activities, net of tax of $23, $(119), $(162), $(606)	(132)	(139)	185	1,155
Net change in pension and postretirement obligation adjustments, net of tax of $102, $(255), $285, $(1,175)	(207)	743	(572)	3,445
Attributable to unconsolidated affiliates, net of tax of $415, $(2,888), $614, $(3,700)	(735)	5,112	(1,086)	6,550
Other, net	0	54	(380)	77
Total other comprehensive income (loss), net	6,080	1,466	13,417	(4,374)
Consolidated comprehensive income	28,834	27,528	94,459	78,612
Comprehensive (income) loss attributable to noncontrolling interests	(499)	(480)	(2,002)	382
Comprehensive income attributable to Mueller Industries, Inc.	$ 28,335	$ 27,048	$ 92,457	$ 78,994

CONDENSED CONSOLIDATED STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Statement of Comprehensive Income [Abstract]
Net change with respect to derivative instruments and hedging activities, tax (expense) benefit	$ 23	$ (119)	$ (162)	$ (606)
Net actuarial loss on pension and postretirement obligations, tax benefit (expense)	102	(255)	285	(1,175)
Attributable to unconsolidated affiliates, tax benefit (expense)	$ 415	$ (2,888)	$ 614	$ (3,700)

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 106,344	$ 351,317
Accounts receivable, less allowance for doubtful accounts of $854 in 2017 and $637 in 2016	276,678	256,291
Inventories	284,114	242,013
Other current assets	25,692	44,702
Total current assets	692,828	894,323
Property, plant, and equipment, net	283,845	295,231
Goodwill, net	139,445	123,993
Intangible assets, net	36,943	36,168
Investment in unconsolidated affiliates	73,664	77,110
Other assets	22,499	20,651
Total assets	1,249,224	1,447,476
Current liabilities:
Current portion of debt	14,450	13,655
Accounts payable	125,032	103,175
Accrued wages and other employee costs	34,096	35,121
Other current liabilities	71,581	67,041
Total current liabilities	245,159	218,992
Long-term debt, less current portion	388,818	213,709
Pension liabilities	14,947	14,890
Postretirement benefits other than pensions	16,930	16,383
Environmental reserves	21,365	21,208
Deferred income taxes	19,963	19,573
Other noncurrent liabilities	12,005	6,284
Total liabilities	719,187	511,039
Mueller Industries, Inc. stockholders' equity:
Preferred stock - $1.00 par value; shares authorized 5,000,000; none outstanding	0	0
Common stock - $.01 par value; shares authorized 100,000,000; issued 80,183,004; outstanding 57,804,707 in 2017 and 57,395,209 in 2016	802	802
Additional paid-in capital	272,667	273,345
Retained earnings	743,560	1,141,831
Accumulated other comprehensive loss	(54,377)	(66,956)
Treasury common stock, at cost	(445,749)	(450,338)
Total Mueller Industries, Inc. stockholders' equity	516,903	898,684
Noncontrolling interests	13,134	37,753
Total equity	530,037	936,437
Commitments and contingencies	0	0
Total liabilities and equity	$ 1,249,224	$ 1,447,476

CONDENSED CONSOLIDATED BALANCE6

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Allowance for doubtful accounts	$ 854	$ 637
Mueller Industries, Inc. stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	80,183,004	80,183,004
Common stock, shares outstanding (in shares)	57,804,707	57,395,209

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016
Cash flows from operating activities
Consolidated net income	$ 81,042	$ 82,986
Reconciliation of consolidated net income to net cash provided by operating activities:
Depreciation and amortization	25,439	27,267
Stock-based compensation expense	5,555	4,553
Loss (income) from unconsolidated affiliates	1,746	(3,049)
Gain on sale of business	(1,491)	0
Gain on disposals of properties	(26)	(747)
Gain on sales of securities	(611)	0
Impairment charges	411	3,000
Deferred income taxes	624	6,491
Changes in assets and liabilities, net of businesses acquired and sold:
Receivables	(33,359)	(45,780)
Inventories	(40,920)	(914)
Other assets	(3,372)	14,428
Current liabilities	20,967	(15,998)
Other liabilities	(1,498)	(2,101)
Other, net	(973)	450
Net cash provided by operating activities	53,534	70,586
Cash flows from investing activities
Capital expenditures	(17,297)	(15,632)
Acquisition of businesses, net of cash acquired	(18,396)	(20,533)
Proceeds from sale of business, net of cash sold	17,483	0
Net withdrawals from restricted cash balances	5,197	1,177
Investment in unconsolidated affiliates	(3,317)	0
Proceeds from sales of assets	11,732	5,301
Proceeds from sales of securities	1,787	0
Net cash used in investing activities	(2,811)	(29,687)
Cash flows from financing activities
Dividends paid to stockholders of Mueller Industries, Inc.	(191,241)	(15,555)
Dividends paid to noncontrolling interests	(2,909)	(3,765)
Issuance of long-term debt	0	2,000
(Repayment) issuance of debt by consolidated joint ventures, net	(3,451)	5,006
Net cash used to settle stock-based awards	(1,644)	(1,356)
Repayments of long-term debt	(100,917)	(769)
Net cash used in financing activities	(300,162)	(14,439)
Effect of exchange rate changes on cash	4,466	(3,511)
(Decrease) increase in cash and cash equivalents	(244,973)	22,949
Cash and cash equivalents at the beginning of the period	351,317	274,844
Cash and cash equivalents at the end of the period	$ 106,344	$ 297,793

Earnings per Common Share

Earnings per Common Share	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings per Common Share	Earnings per Common Share Basic per share amounts have been computed based on the average number of common shares outstanding. Diluted per share amounts reflect the increase in average common shares outstanding that would result from the assumed exercise of outstanding stock options and vesting of restricted stock awards, computed using the treasury stock method. Approximately 52 thousand and 218 thousand stock-based awards were excluded from the computation of diluted earnings per share for the quarters ended September 30, 2017 and October 1, 2016 , respectively, because they were antidilutive.

Special Dividend

Special Dividend	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Special Dividend	Special Dividend On March 9, 2017, the Company distributed a special dividend of $3.00 in cash and $5.00 in principal amount of the Company’s 6% Subordinated Debentures (Debentures) due March 1, 2027 for each share of common stock outstanding. Interest on the Debentures is payable semiannually on September 1 and March 1, commencing September 1, 2017. At issuance, the Debentures were recorded at their estimated fair value. The fair value of the Debentures was estimated based on quoted market prices for the same or similar issues, the current rates offered to the Company for debt of the same remaining maturities, or the use of market standard models. The carrying value of the Debentures approximates fair value at September 30, 2017 . The Debentures are subordinated to all other funded debt of the Company and are callable, in whole or in part, at any time at the option of the Company, subject to declining call premiums during the first five years. The Debentures also grant each holder the right to require the Company to repurchase such holder’s Debentures in the event of a change in control at declining repurchase premiums during the first five years. The Debentures may be redeemed, subject to the conditions set forth above, at the following redemption price (expressed as a percentage of principal amount) plus any accrued but unpaid interest to, but excluding, the redemption date: If redeemed during the 12-month period beginning March 9: Year Redemption Price 2017 106% 2018 105 2019 104 2020 103 2021 102 2022 and thereafter 100 The effect of the special dividend was a decrease in stockholders’ equity of approximately $ 458.7 million , an increase in long-term debt of approximately $ 284.5 million , and a decrease in cash of approximately $ 174.2 million .

Acquisitions and Dispositions

Acquisitions and Dispositions	9 Months Ended
	Sep. 30, 2017
Acquisitions and Dispositions [Abstract]
Acquisitions and Dispositions	Acquisitions and Dispositions Acquisitions On May 31, 2017, the Company entered into a share purchase agreement pursuant to which the Company acquired all of the outstanding shares of Pexcor Manufacturing Company Inc. (Pexcor) and Heatlink Group Inc. (Heatlink) for approximately $18.5 million , net of working capital adjustments. The total purchase price consisted of $16.3 million in cash at closing and a contingent consideration arrangement which requires the Company to pay the former owners up to $2.2 million based on EBITDA growth of the acquired companies. Pexcor and Heatlink, based out of Calgary, Canada, produce and sell a complete line of products for PEX plumbing and radiant systems. These businesses complement the Company’s existing businesses within the Piping Systems segment. The fair value of the assets acquired totaled $10.4 million , consisting primarily of inventories of $4.5 million , accounts receivable of $2.8 million , property, plant, and equipment of $2.0 million , other current assets of $0.5 million , and other assets of $0.6 million . The fair value of the liabilities assumed totaled $4.3 million , consisting primarily of accounts payable of $3.6 million , other current liabilities of $0.4 million , and other liabilities of $0.3 million . Of the remaining purchase price, $12.4 million was allocated to non-deductible goodwill and intangible assets. The purchase price allocation is provisional as of September 30, 2017 and subject to change upon completion of the final valuation of the long-lived assets, working capital, and contingent consideration during the measurement period. On April 26, 2016, the Company entered into an agreement pursuant to which the Company acquired a 60 percent equity interest in Jungwoo Metal Ind. Co., LTD (Jungwoo-Mueller) for approximately $20.5 million in cash. Jungwoo-Mueller, which manufactures copper-based pipe joining products, is headquartered in Seoul, South Korea and serves markets worldwide. This business complements the Company’s existing copper fittings business in the Piping Systems segment and is reported in the Company’s Condensed Consolidated Financial Statements one month in arrears. The fair value of the assets acquired totaled $49.0 million , consisting primarily of property, plant, and equipment of $24.2 million , inventories of $17.6 million , accounts receivable of $5.6 million , other current assets of $1.4 million , and deferred tax assets of $0.2 million . The fair value of the liabilities assumed totaled $17.9 million , consisting primarily of long-term debt of $8.7 million , accounts payable of $7.3 million , pension liabilities of $0.8 million , other current liabilities of $0.5 million , and other liabilities of $0.6 million . Of the remaining purchase price, $1.0 million was allocated to non-deductible goodwill and intangible assets. The noncontrolling interest in Jungwoo-Mueller is $11.6 million . The valuation of the business has been finalized. Changes to the purchase price allocation from the amounts presented in the Company’s 2016 Annual Report on Form 10-K were immaterial. Dispositions On June 21, 2017, the Company entered into a definitive equity transfer agreement with Jiangsu Xingrong Hi-Tech Co. Ltd. and Jiangsu Baiyang Industries Co. Ltd. (Baiyang), together, the minority partners in Mueller-Xingrong (the Company’s Chinese joint venture), pursuant to which the Company sold its 50.5 percent equity interest in Mueller-Xingrong to Baiyang for approximately $18.3 million . Mueller-Xingrong manufactures engineered copper tube primarily for air-conditioning applications in China and was included in the Piping Systems segment. Mueller-Xingrong reported net sales of $67.3 million and net losses of $9 thousand in the first nine months of 2017 compared to net sales of $69.6 million and net income of $426 thousand in the first nine months of 2016 . The carrying value of the assets disposed totaled $56.7 million , consisting primarily of accounts receivable, inventories, and long-lived assets. The carrying value of the liabilities disposed (consisting primarily of current debt and accounts payable), noncontrolling interest, and amounts recognized in accumulated other comprehensive income (AOCI) totaled $36.2 million . Since the disposal constituted a complete liquidation of the Company’s investment in a foreign entity, the Company removed from AOCI and recognized a cumulative translation gain of $3.8 million . As a result of the disposal, the Company recognized a net gain on the sale of this business of $1.5 million as a reduction of selling, general, and administrative expense in the Condensed Consolidated Financial Statements.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Segment Information	Segment Information Each of the Company’s reportable segments is composed of certain operating segments that are aggregated primarily by the nature of products offered as follows: Piping Systems Piping Systems is composed of the following operating segments: Domestic Piping Systems Group, Great Lakes Copper, Pexcor & Heatlink, European Operations, Trading Group, and Jungwoo-Mueller (the Company’s South Korean joint venture). The Domestic Piping Systems Group manufactures copper tube and fittings, plastic fittings, and line sets. These products are manufactured in the U.S., sold in the U.S, and exported to markets worldwide. Outside the U.S., Great Lakes Copper manufactures copper tube and line sets and sells the products primarily in the U.S. and Canada, Pexcor & Heatlink produce a complete line of products for PEX plumbing and radiant systems in Canada, and the European Operations manufacture copper tube in the U.K. which is sold primarily in Europe. The Trading Group manufactures pipe nipples and imports and resells brass and plastic plumbing valves, malleable iron fittings, faucets, and plumbing specialty products in the U.S. and Mexico. Jungwoo-Mueller manufactures copper-based joining products that are sold worldwide. The Piping Systems segment’s products are sold primarily to plumbing, refrigeration, and air-conditioning wholesalers, hardware wholesalers and co-ops, building product retailers, and air-conditioning original equipment manufacturers (OEMs). The Company disposed of Mueller-Xingrong (the Company’s Chinese joint venture) on June 21, 2017. This business manufactured engineered copper tube primarily for air-conditioning applications in China. Industrial Metals Industrial Metals is composed of the following operating segments: Brass Rod & Copper Bar Products, Impacts & Micro Gauge, and Brass Value-Added Products. These businesses manufacture brass rod, impact extrusions, and forgings, as well as a wide variety of end products including plumbing brass, automotive components, valves, fittings, and gas assemblies. These products are manufactured in the U.S. and sold primarily to OEMs in the U.S., many of which are in the industrial, construction, heating, ventilation, and air-conditioning, plumbing, and refrigeration markets. Climate Climate is composed of the following operating segments: Refrigeration Products, Fabricated Tube Products, Westermeyer, and Turbotec. These domestic businesses manufacture and fabricate valves, assemblies, high pressure components, and coaxial heat exchangers primarily for the heating, ventilation, air-conditioning, and refrigeration markets in the U.S. Summarized segment information is as follows: For the Quarter Ended September 30, 2017 (In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 384,078 $ 147,578 $ 32,488 $ (13,781 ) $ 550,363 Cost of goods sold 340,191 120,021 24,111 (13,061 ) 471,262 Depreciation and amortization 5,290 1,845 636 495 8,266 Selling, general, and administrative expense 17,873 2,667 2,312 10,424 33,276 Operating income 20,724 23,045 5,429 (11,639 ) 37,559 Interest expense (5,237 ) Other (expense) income, net (458 ) Income before income taxes $ 31,864 Segment Information (continued): For the Quarter Ended October 1, 2016 (In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 351,557 $ 131,350 $ 30,003 $ (6,326 ) $ 506,584 Cost of goods sold 301,867 107,512 22,210 (6,921 ) 424,668 Depreciation and amortization 5,905 1,964 612 535 9,016 Selling, general, and administrative expense 16,647 3,125 2,357 10,284 32,413 Asset impairments 3,000 — — — 3,000 Operating income 24,138 18,749 4,824 (10,224 ) 37,487 Interest expense (1,830 ) Other income, net 120 Income before income taxes $ 35,777 For the Nine Months Ended September 30, 2017 ( In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 1,205,697 $ 451,919 $ 103,403 $ (18,470 ) $ 1,742,549 Cost of goods sold 1,049,098 377,036 77,124 (19,258 ) 1,484,000 Depreciation and amortization 16,223 5,647 1,880 1,466 25,216 Selling, general, and administrative expense 54,293 8,761 7,244 32,655 102,953 Asset impairments 411 — — — 411 Operating income 85,672 60,475 17,155 (33,333 ) 129,969 Interest expense (14,210 ) Other income, net 324 Income before income taxes $ 116,083 Segment Information (continued): For the Nine Months Ended October 1, 2016 ( In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 1,109,109 $ 393,608 $ 92,068 $ (11,321 ) $ 1,583,464 Cost of goods sold 949,015 321,615 68,363 (11,623 ) 1,327,370 Depreciation and amortization 17,341 6,219 1,829 1,608 26,997 Selling, general, and administrative expense 51,497 9,989 7,336 33,885 102,707 Asset impairments 3,000 — — — 3,000 Operating income 88,256 55,785 14,540 (35,191 ) 123,390 Interest expense (5,370 ) Other income, net 880 Income before income taxes $ 118,900

Inventories

Inventories	9 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories (In thousands) September 30, December 31, 2016 Raw materials and supplies $ 77,743 $ 57,387 Work-in-process 47,651 42,227 Finished goods 165,090 149,288 Valuation reserves (6,370 ) (6,889 ) Inventories $ 284,114 $ 242,013

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities The Company’s earnings and cash flows are subject to fluctuations due to changes in commodity prices, foreign currency exchange rates, and interest rates. The Company uses derivative instruments such as commodity futures contracts, foreign currency forward contracts, and interest rate swaps to manage these exposures. All derivatives are recognized in the Condensed Consolidated Balance Sheets at their fair value. On the date the derivative contract is entered into, it is either a) designated as a hedge of (i) a forecasted transaction or the variability of cash flow to be paid (cash flow hedge) or (ii) the fair value of a recognized asset or liability (fair value hedge), or b) not designated in a hedge accounting relationship, even though the derivative contract was executed to mitigate an economic exposure (economic hedge), as the Company does not enter into derivative contracts for trading purposes. Changes in the fair value of a derivative that is qualified, designated and highly effective as a cash flow hedge are recorded in stockholders’ equity within AOCI, to the extent effective, until they are reclassified to earnings in the same period or periods during which the hedged transaction affects earnings. Changes in the fair value of a derivative that is qualified, designated and highly effective as a fair value hedge, along with the gain or loss on the hedged recognized asset or liability that is attributable to the hedged risk, are recorded in current earnings. Changes in the fair value of undesignated derivatives executed as economic hedges and the ineffective portion of designated derivatives are reported in current earnings. The Company documents all relationships between derivative instruments and hedged items, as well as the risk-management objective and strategy for undertaking various hedge transactions. This process includes linking all derivative instruments that are designated as fair value hedges to specific assets and liabilities in the Condensed Consolidated Balance Sheets and linking cash flow hedges to specific forecasted transactions or variability of cash flow. The Company also assesses, both at the hedge’s inception and on an ongoing basis, whether the designated derivative instruments that are used in hedging transactions are highly effective in offsetting changes in cash flows or fair values of hedged items. When a derivative instrument is determined not to be highly effective as a hedge or the underlying hedged transaction is no longer probable of occurring, hedge accounting is discontinued prospectively in accordance with the derecognition criteria for hedge accounting. Commodity Futures Contracts Copper and brass represent the largest component of the Company’s variable costs of production. The cost of these materials is subject to global market fluctuations caused by factors beyond the Company’s control. The Company occasionally enters into forward fixed-price arrangements with certain customers; the risk of these arrangements is generally managed with commodity futures contracts. These futures contracts have been designated as cash flow hedges. At September 30, 2017 , the Company held open futures contracts to purchase approximately $11.8 million of copper over the next 15 months related to fixed price sales orders. The fair value of those futures contracts was a $165 thousand net loss position, which was determined by obtaining quoted market prices (level 1 within the fair value hierarchy). In the next 12 months, the Company will reclassify into earnings realized gains or losses relating to cash flow hedges. At September 30, 2017 , this amount was approximately $133 thousand of deferred net losses , net of tax. The Company may also enter into futures contracts to protect the value of inventory against market fluctuations. At September 30, 2017 , the Company held open futures contracts to sell approximately $57.7 million of copper over the next six months related to copper inventory. The fair value of those futures contracts was a $726 thousand net loss position, which was determined by obtaining quoted market prices (level 1 within the fair value hierarchy). Interest Rate Swap On February 20, 2013, the Company entered into a two -year forward-starting interest rate swap agreement with an effective date of January 12, 2015, and an underlying notional amount of $200.0 million , pursuant to which the Company receives variable interest payments based on one-month LIBOR and pays fixed interest at a rate of 1.4 percent . Based on the Company’s current variable premium pricing on its revolving credit facility, the all-in fixed rate is 2.98 percent . The interest rate swap will mature on December 11, 2017 , and is structured to offset the interest rate risk associated with the Company’s floating-rate, LIBOR-based Credit Agreement. The swap was designated and accounted for as a cash flow hedge at inception. During the fourth quarter of 2016, the Company discontinued hedge accounting prospectively. The fair value of the interest rate swap is estimated based on the present value of the difference between expected cash flows calculated at the contracted interest rate and the expected cash flows at the current market interest rate using observable benchmarks for LIBOR forward rates at the end of the period (level 2 within the fair value hierarchy). Interest payable and receivable under the swap agreement is accrued and recorded as an adjustment to interest expense. The fair value of the interest rate swap was a $49 thousand loss position at September 30, 2017 , and there was $107 thousand of deferred losses , net of tax, included in AOCI that are expected to be reclassified into interest expense over the remaining term of the interest rate swap. The Company presents its derivative assets and liabilities in the Condensed Consolidated Balance Sheets on a net basis by counterparty. The following table summarizes the location and fair value of the derivative instruments and disaggregates the net derivative assets and liabilities into gross components on a contract-by-contract basis: Asset Derivatives Liability Derivatives Fair Value Fair Value (In thousands) Balance Sheet Location September 30, 2017 December 31, 2016 Balance Sheet Location September 30, 2017 December 31, 2016 Commodity contracts - gains Other current assets $ 203 $ 1,013 Other current liabilities $ 796 $ 564 Commodity contracts - losses Other current assets (120 ) (148 ) Other current liabilities (1,770 ) (920 ) Interest rate swap Other current assets — — Other current liabilities (49 ) (787 ) Total derivatives (1) $ 83 $ 865 $ (1,023 ) $ (1,143 ) (1) Does not include the impact of cash collateral provided to counterparties. The following tables summarize the effects of derivative instruments on the Company’s Condensed Consolidated Statements of Income: For the Quarter Ended For the Nine Months Ended (In thousands) Location September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Fair value hedges: Gain (loss) on commodity contracts (qualifying) Cost of goods sold $ — $ (37 ) $ — $ (420 ) Gain on hedged item - inventory Cost of goods sold — 32 — 382 Undesignated derivatives: (Loss) gain on commodity contracts (nonqualifying) Cost of goods sold (3,083 ) 855 (3,506 ) 2,676 The following tables summarize amounts recognized in and reclassified from AOCI during the period: For the Quarter Ended September 30, 2017 (In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (541 ) Cost of goods sold $ 237 Interest rate swap — Interest expense 149 Other 23 Other — Total $ (518 ) Total $ 386 Derivative Instruments and Hedging Activities (continued): For the Quarter Ended October 1, 2016 (In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (1,434 ) Cost of goods sold $ 814 Interest rate swap 457 Interest expense 58 Other (32 ) Other — Total $ (1,009 ) Total $ 872 For the Nine Months Ended September 30, 2017 ( In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (1,354 ) Cost of goods sold $ 913 Interest rate swap — Interest expense 447 Other 179 Other — Total $ (1,175 ) Total $ 1,360 For the Nine Months Ended October 1, 2016 ( In thousands) Gain (Loss) Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) (Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ 1,903 Cost of goods sold $ (477 ) Interest rate swap (128 ) Interest expense 186 Other (329 ) Other — Total $ 1,446 Total $ (291 ) The Company enters into futures and forward contracts that closely match the terms of the underlying transactions. As a result, the ineffective portion of the open hedge contracts through September 30, 2017 was not material to the Condensed Consolidated Statements of Income. The Company primarily enters into International Swaps and Derivatives Association master netting agreements with major financial institutions that permit the net settlement of amounts owed under their respective derivative contracts. Under these master netting agreements, net settlement generally permits the Company or the counterparty to determine the net amount payable for contracts due on the same date and in the same currency for similar types of derivative transactions. The master netting agreements generally also provide for net settlement of all outstanding contracts with a counterparty in the case of an event of default or a termination event. The Company does not offset fair value amounts for derivative instruments and fair value amounts recognized for the right to reclaim cash collateral. At September 30, 2017 and December 31, 2016 , the Company had recorded restricted cash in other current assets of $3.0 million and $1.4 million , respectively, as collateral related to open derivative contracts under the master netting arrangements.

Investment in Unconsolidated Af

Investment in Unconsolidated Affiliates	9 Months Ended
	Sep. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Investment in Unconsolidated Affiliates	Investment in Unconsolidated Affiliates The Company owns a 50 percent interest in Tecumseh Products Holdings LLC (Joint Venture), an unconsolidated affiliate that acquired Tecumseh Products Company (Tecumseh) during the third quarter of 2015. The Company also owns a 50 percent interest in a second unconsolidated affiliate that provided financing to Tecumseh in conjunction with the acquisition. These investments are recorded using the equity method of accounting, as the Company can exercise significant influence but does not own a majority equity interest or otherwise control the respective entities. Under the equity method of accounting, these investments are stated at initial cost and are adjusted for subsequent additional investments and the Company’s proportionate share of earnings or losses and distributions. The Company records its proportionate share of the investees’ net income or loss one quarter in arrears as income (loss) from unconsolidated affiliates, net of tax, in the Condensed Consolidated Statements of Income and its proportionate share of the investees’ other comprehensive income (loss), net of income taxes, in the Condensed Consolidated Statements of Comprehensive Income. In general, the equity investment in unconsolidated affiliates is equal to the current equity investment plus the entities’ undistributed earnings. The following tables present summarized financial information derived from the Company’s equity method investees’ combined consolidated financial statements, which are prepared in accordance with U.S. GAAP. September 30, December 31, 2016 Current assets $ 251,188 $ 244,323 Noncurrent assets 132,000 130,400 Current liabilities 177,110 148,806 Noncurrent liabilities 59,334 71,681 For the Quarter Ended For the Nine Months Ended (In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Net sales $ 148,400 $ 146,700 $ 407,300 $ 437,200 Gross profit 21,500 22,200 56,700 59,700 Net (loss) income (788 ) 2,244 (3,492 ) 6,097 The Company’s income from unconsolidated affiliates, net of tax, for the nine months ended October 1, 2016 included a gain of $17.1 million that resulted from the allocation of the purchase price, which was partially offset by restructuring and impairment charges of $5.3 million and net losses of $5.7 million . On December 30, 2015, the Company entered into a joint venture agreement with Cayan Ventures and Bahrain Mumtalakat Holding Company to build a copper tube mill in Bahrain. The business will operate and brand its products under the Mueller Industries family of brands. The Company has invested approximately $3.9 million of cash to date and will be the technical and marketing lead in return for 40 percent ownership in the joint venture.

Benefit Plans

Benefit Plans	9 Months Ended
	Sep. 30, 2017
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Benefit Plans The Company sponsors several qualified and nonqualified pension plans and other postretirement benefit plans for certain of its employees. The components of net periodic benefit cost (income) are as follows: For the Quarter Ended For the Nine Months Ended (In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Pension benefits: Service cost $ 35 $ 180 $ 106 $ 540 Interest cost 1,659 1,973 4,977 5,917 Expected return on plan assets (2,184 ) (2,466 ) (6,552 ) (7,398 ) Amortization of net loss 536 760 1,608 2,280 Net periodic benefit cost $ 46 $ 447 $ 139 $ 1,339 Other benefits: Service cost $ 54 $ 61 $ 163 $ 183 Interest cost 147 153 442 458 Amortization of prior service credit (225 ) (224 ) (676 ) (672 ) Amortization of net gain (10 ) (9 ) (30 ) (27 ) Net periodic benefit income $ (34 ) $ (19 ) $ (101 ) $ (58 )

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is involved in certain litigation as a result of claims that arose in the ordinary course of business, which management believes will not have a material adverse effect on the Company’s financial position, results of operations, or cash flows. The Company may also realize the benefit of certain legal claims and litigation in the future; these gain contingencies are not recognized in the Condensed Consolidated Financial Statements. Lead Refinery Site U.S.S. Lead Refinery, Inc. (Lead Refinery), a non-operating wholly owned subsidiary of MRRC, has conducted corrective action and interim remedial activities (collectively, Site Activities) at Lead Refinery’s East Chicago, Indiana site pursuant to the Resource Conservation and Recovery Act since December 1996. Although the Site Activities have been substantially concluded, Lead Refinery is required to perform monitoring and maintenance-related activities pursuant to a post-closure permit issued by the Indiana Department of Environmental Management effective as of March 2, 2013. Approximate costs to comply with the post-closure permit, including associated general and administrative costs, are estimated at between $2.1 million and $4.7 million over the next 20 years . On April 9, 2009, pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the U.S. Environmental Protection Agency (EPA) added the Lead Refinery site and surrounding properties to the National Priorities List (NPL). On July 17, 2009, Lead Refinery received a written notice from the EPA indicating that it may be a PRP under CERCLA due to the release or threat of release of hazardous substances including lead into properties surrounding the Lead Refinery site. The EPA identified two other PRPs in connection with that matter. In November 2012, the EPA adopted a remedy for the surrounding properties and in September 2014, the EPA announced that it had entered into a settlement with the two other PRPs whereby they will pay approximately $26.0 million to fund the cleanup of approximately 300 properties surrounding the Lead Refinery site and perform certain remedial action tasks. On November 8, 2016, the Company, its subsidiary Arava Natural Resources Company, Inc. (Arava), and Arava’s subsidiary MRRC each received general notice letters from the EPA asserting that they may be PRPs in connection with the Lead Refinery NPL site. The Company, Arava, and MRRC have denied liability for any remedial action and response costs associated with the Lead Refinery NPL site. In June 2017, the EPA requested that Lead Refinery conduct, and the Company fund, a remedial investigation and feasibility study of the Lead Refinery NPL site pursuant to a proposed administrative settlement agreement and order on consent. The Company and Lead Refinery entered into that agreement in September 2017. The Company will make a capital contribution to Lead Refinery to conduct the remedial investigation and feasibility study and provide a financial guarantee in the amount of $1.0 million . The EPA has also informed the Company that the EPA’s position is that Mueller is a responsible party for the Lead Refinery NPL site, and accordingly is responsible for a share of remedial action and response costs at the site and in the adjacent residential area. At this juncture, the Company is unable to determine the likelihood of a material adverse outcome or the amount or range of a potential loss with respect to any remedial action related to the Lead Refinery NPL site. Equal Employment Opportunity Commission Matter On October 5, 2016, the Company received a demand letter from the Los Angeles District Office of the United States Equal Employment Opportunity Commission (EEOC). The EEOC alleges that between May 2011 and April 2015, various Company employees were terminated in violation of the Americans with Disabilities Act, and that certain of the Company’s employee leave and attendance policies were discriminatory in nature. On that basis, the EEOC’s letter includes a demand for monetary relief on behalf of an identified class of 20 individuals, and an unidentified class of 150 individuals, in addition to injunctive relief. The Company believes the EEOC’s allegations are without merit. Notwithstanding the Company’s position, in consultation with its liability insurers, the Company entered into a conciliation process with the EEOC for purposes of resolving the claims. On April 12, 2017, the Company received a letter from the EEOC stating that the conciliation process had concluded without a resolution of the claims, and that the matter would be referred to its Legal Department for potential litigation. Due to the procedural stage of this matter, the Company is unable to determine the likelihood of a material adverse outcome in this matter, or the amount or range of a potential loss in excess of any available insurance coverage. Guarantees Guarantees, in the form of letters of credit, are issued by the Company generally to assure the payment of insurance deductibles and certain retiree health benefits. The terms of the guarantees are generally one year but are renewable annually as required. These letters are primarily backed by the Company’s revolving credit facility. The maximum payments that the Company could be required to make under its guarantees at September 30, 2017 were $8.4 million .

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rate for the third quarter of 2017 was 27 percent compared with 30 percent for the same period last year. The items impacting the effective tax rate for the third quarter of 2017 were primarily attributable to reductions for the U.S. production activities deduction of $0.6 million , the effect of foreign tax rates lower than statutory tax rates of $1.6 million , and the tax benefit of equity compensation deductions of $0.5 million . For the third quarter of 2016 , the difference between the effective tax rate and the amount computed using the U.S. federal statutory rate was primarily attributable to reductions for the U.S. production activities deduction of $0.6 million , the effect of foreign tax rates lower than statutory rates of $1.0 million , and the tax benefit of equity compensation deductions of $0.8 million . These items were partially offset by the provision for state income taxes, net of the federal benefit, of $0.6 million . The Company’s effective tax rate for the first nine months of 2017 was 29 percent compared with 33 percent for the same period last year. The items impacting the effective tax rate for the first nine months of 2017 were primarily attributable to reductions for the U.S. production activities deduction of $2.4 million , the effect of foreign tax rates lower than statutory tax rates of $4.6 million , the tax benefit of equity compensation deductions of $2.2 million , and the impact of investments in unconsolidated affiliates of $0.9 million . These items were partially offset by the provision for state income taxes, net of the federal benefit, of $1.7 million . For the first nine months of 2016 , the difference between the effective tax rate and the amount computed using the U.S. federal statutory tax rate was primarily attributable to reductions for the U.S. production activities deduction of $2.5 million , the effect of foreign tax rates lower than statutory rates of $3.5 million , and the tax benefit of equity compensation deductions of $0.8 million . These items were partially offset by the provision for state income taxes, net of the federal benefit, of $2.3 million and the impact of investments in unconsolidated affiliates of $1.2 million . The Company files a consolidated U.S. federal income tax return and numerous consolidated and separate-company income tax returns in many state, local, and foreign jurisdictions. The statute of limitations is open for the Company’s federal tax return and most state income tax returns for 2014 and all subsequent years and is open for certain state and foreign returns for earlier tax years due to ongoing audits and differing statute periods. While the Company believes that it is adequately reserved for possible future audit adjustments, the final resolution of these examinations cannot be determined with certainty and could result in final settlements that differ from current estimates.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income AOCI includes certain foreign currency translation adjustments from those subsidiaries not using the U.S. dollar as their functional currency, net deferred gains and losses on certain derivative instruments accounted for as cash flow hedges, adjustments to pension and OPEB liabilities, unrealized gains and losses on marketable securities classified as available-for-sale, and other comprehensive income attributable to unconsolidated affiliates. The following table provides changes in AOCI by component, net of taxes and noncontrolling interests (amounts in parentheses indicate debits to AOCI): For the Nine Months Ended September 30, 2017 (In thousands) Cumulative Translation Adjustment Unrealized (Loss) Gain on Derivatives Pension/OPEB Liability Adjustment Unrealized Gain (Loss) on Equity Securities Attributable to Unconsol. Affiliates Total Balance as of December 31, 2016 $ (49,965 ) $ (300 ) $ (23,046 ) 380 $ 5,975 $ (66,956 ) Other comprehensive income (loss) before reclassifications 18,209 (1,175 ) (1,309 ) (1 ) (1,086 ) 14,638 Amounts reclassified from AOCI (3,777 ) 1,360 737 (379 ) — (2,059 ) Net current-period other comprehensive income (loss) 14,432 185 (572 ) (380 ) (1,086 ) 12,579 Balance as of September 30, 2017 $ (35,533 ) $ (115 ) $ (23,618 ) — $ 4,889 $ (54,377 ) For the Nine Months Ended October 1, 2016 (In thousands) Cumulative Translation Adjustment Unrealized (Loss) Gain on Derivatives Pension/OPEB Liability Adjustment Unrealized Gain on Equity Securities Attributable to Unconsol. Affiliates Total Balance as of December 26, 2015 $ (24,773 ) $ (2,009 ) $ (28,429 ) 221 $ — $ (54,990 ) Other comprehensive (loss) income before reclassifications (14,638 ) 1,446 2,258 77 6,550 (4,307 ) Amounts reclassified from AOCI — (291 ) 1,187 — — 896 Net current-period other comprehensive (loss) income (14,638 ) 1,155 3,445 77 6,550 (3,411 ) Balance as of October 1, 2016 $ (39,411 ) $ (854 ) $ (24,984 ) 298 $ 6,550 $ (58,401 ) Reclassification adjustments out of AOCI were as follows: Amount reclassified from AOCI For the Quarter Ended For the Nine Months Ended ( In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Affected line item Unrealized losses (gains) on derivatives: Commodity contracts $ 223 $ 848 $ 1,247 $ (1,023 ) Cost of goods sold Interest rate swap 232 91 696 291 Interest expense (69 ) (67 ) (583 ) 441 Income tax (benefit) expense $ 386 $ 872 $ 1,360 $ (291 ) Net of tax and noncontrolling interests Amortization of net loss and prior service cost on employee benefit plans $ 301 $ 527 $ 902 $ 1,581 Selling, general, and administrative (55 ) (132 ) (165 ) (394 ) Income tax benefit $ 246 $ 395 $ 737 $ 1,187 Net of tax and noncontrolling interests Sale of available-for-sale securities $ — $ — $ (611 ) $ — Other income $ — $ — $ 232 $ — Income tax expense $ — $ — $ (379 ) $ — Net of tax and noncontrolling interests Gain recognized upon sale of business $ — $ — $ (3,777 ) $ — Selling, general, and administrative $ — $ — $ — $ — Income tax expense $ — $ — $ (3,777 ) $ — Net of tax and noncontrolling interests

Noncontrolling Interests

Noncontrolling Interests	9 Months Ended
	Sep. 30, 2017
Noncontrolling Interest [Abstract]
Noncontrolling Interests	Noncontrolling Interests (In thousands) Noncontrolling Interests Balance as of December 31, 2016 $ 37,753 Sale of Mueller-Xingrong (23,712 ) Dividends paid to noncontrolling interests (2,909 ) Net income attributable to noncontrolling interests 1,164 Other comprehensive income attributable to noncontrolling interests, net of tax: Foreign currency translation 838 Balance as of September 30, 2017 $ 13,134

Recently Issued Accounting Stan

Recently Issued Accounting Standards	9 Months Ended
	Sep. 30, 2017
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Standards	Recently Issued Accounting Standards In March 2017, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost . The ASU requires employers that sponsor defined benefit pension and/or other postretirement benefit plans to present the service cost component of net periodic benefit cost in the same income statement line item(s) as other employee compensation costs arising from services rendered during the period and other components of net periodic benefits cost separately from the line item(s) that includes the service cost and outside of any subtotal of operating income. The guidance is effective for the Company in interim and annual periods beginning in 2018. Early adoption is permitted as of the beginning of an annual period for which financial statements have not been issued or made available for issuance. The Company does not expect the adoption of the standard to have a material impact on its Condensed Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . The ASU eliminates step two from the goodwill impairment test and instead requires an entity to perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. The entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value, not to exceed the total amount of goodwill allocated to the reporting unit. The updated guidance requires a prospective adoption. Early adoption is permitted. The guidance is effective for the Company beginning in 2020. The Company is in the process of evaluating the effects of the provisions of the ASU on its Condensed Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business . The ASU provides guidance to assist entities in evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The updated guidance requires a prospective adoption. Early adoption is permitted. This update will be effective for the Company beginning in 2018. The Company does not expect the provisions of the ASU to have a material impact on its Condensed Consolidated Financial Statements. In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers . The ASU provides correction or improvement to the guidance previously issued in ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . Under the ASU, an entity will recognize revenue to depict the transfer of promised goods or services to customers at an amount that reflects the consideration that it expects to receive in exchange for the goods or services. It also requires more detailed disclosures to enable users of financial statements to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. This guidance is effective for the Company at the beginning of 2018. The standard permits the use of either the full retrospective or cumulative transition effect (modified retrospective) method. The Company currently expects to adopt the standard using the modified retrospective approach. The ASU requires revenue to be recognized over time (i.e., throughout the production process) rather than at a point in time (generally upon shipment to the customer) if performance does not create an asset with an alternative use to the entity and the entity has an enforceable right to payment for performance completed to date. The Company is evaluating specific contract terms, primarily within the Industrial Metals and Climate segments, related to the production of customized products and payment rights to evaluate whether revenue from certain contracts will be recognized over time under the ASU. As part of the overall evaluation of the standard, the Company is assessing potential changes to its accounting policies, practices, and internal controls over financial reporting to support the standard. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash . The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash, and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The guidance will be applied retrospectively and is effective for public business entities in interim and annual periods beginning after December 15, 2017. Early adoption is permitted. The Company does not expect the adoption of the standard to have a material impact on its Condensed Consolidated Financial Statements. In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory . The ASU requires companies to account for the income tax effects of intercompany transfers of assets other than inventory when the transfer occurs. Companies will still be required to defer the income tax effects of intercompany inventory transactions in an exception to the income tax accounting guidance. The guidance is effective for public business entities in annual periods beginning after December 15, 2017. Early adoption is permitted as of the beginning of an annual period. The Company is still evaluating the effects that the provisions of the ASU will have on its Condensed Consolidated Financial Statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . The ASU requires an entity to recognize a right-of-use asset and lease liability for all leases with terms of more than 12 months. Recognition, measurement and presentation of expenses will depend on classification as a financing or operating lease. The amendments also require certain quantitative and qualitative disclosures about leasing arrangements. The ASU will be effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The updated guidance requires a modified retrospective adoption. The Company is still evaluating the effects that the provision of the ASU will have on its Condensed Consolidated Financial Statements.

Recently Issued Accounting St21

Recently Issued Accounting Standards (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Standards	In March 2017, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost . The ASU requires employers that sponsor defined benefit pension and/or other postretirement benefit plans to present the service cost component of net periodic benefit cost in the same income statement line item(s) as other employee compensation costs arising from services rendered during the period and other components of net periodic benefits cost separately from the line item(s) that includes the service cost and outside of any subtotal of operating income. The guidance is effective for the Company in interim and annual periods beginning in 2018. Early adoption is permitted as of the beginning of an annual period for which financial statements have not been issued or made available for issuance. The Company does not expect the adoption of the standard to have a material impact on its Condensed Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-04, Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . The ASU eliminates step two from the goodwill impairment test and instead requires an entity to perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. The entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value, not to exceed the total amount of goodwill allocated to the reporting unit. The updated guidance requires a prospective adoption. Early adoption is permitted. The guidance is effective for the Company beginning in 2020. The Company is in the process of evaluating the effects of the provisions of the ASU on its Condensed Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business . The ASU provides guidance to assist entities in evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The updated guidance requires a prospective adoption. Early adoption is permitted. This update will be effective for the Company beginning in 2018. The Company does not expect the provisions of the ASU to have a material impact on its Condensed Consolidated Financial Statements. In December 2016, the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers . The ASU provides correction or improvement to the guidance previously issued in ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . Under the ASU, an entity will recognize revenue to depict the transfer of promised goods or services to customers at an amount that reflects the consideration that it expects to receive in exchange for the goods or services. It also requires more detailed disclosures to enable users of financial statements to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. This guidance is effective for the Company at the beginning of 2018. The standard permits the use of either the full retrospective or cumulative transition effect (modified retrospective) method. The Company currently expects to adopt the standard using the modified retrospective approach. The ASU requires revenue to be recognized over time (i.e., throughout the production process) rather than at a point in time (generally upon shipment to the customer) if performance does not create an asset with an alternative use to the entity and the entity has an enforceable right to payment for performance completed to date. The Company is evaluating specific contract terms, primarily within the Industrial Metals and Climate segments, related to the production of customized products and payment rights to evaluate whether revenue from certain contracts will be recognized over time under the ASU. As part of the overall evaluation of the standard, the Company is assessing potential changes to its accounting policies, practices, and internal controls over financial reporting to support the standard. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash . The ASU requires entities to show the changes in the total of cash, cash equivalents, restricted cash, and restricted cash equivalents in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statement of cash flows. The guidance will be applied retrospectively and is effective for public business entities in interim and annual periods beginning after December 15, 2017. Early adoption is permitted. The Company does not expect the adoption of the standard to have a material impact on its Condensed Consolidated Financial Statements. In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory . The ASU requires companies to account for the income tax effects of intercompany transfers of assets other than inventory when the transfer occurs. Companies will still be required to defer the income tax effects of intercompany inventory transactions in an exception to the income tax accounting guidance. The guidance is effective for public business entities in annual periods beginning after December 15, 2017. Early adoption is permitted as of the beginning of an annual period. The Company is still evaluating the effects that the provisions of the ASU will have on its Condensed Consolidated Financial Statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . The ASU requires an entity to recognize a right-of-use asset and lease liability for all leases with terms of more than 12 months. Recognition, measurement and presentation of expenses will depend on classification as a financing or operating lease. The amendments also require certain quantitative and qualitative disclosures about leasing arrangements. The ASU will be effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The updated guidance requires a modified retrospective adoption. The Company is still evaluating the effects that the provision of the ASU will have on its Condensed Consolidated Financial Statements.

Special Dividend (Tables)

Special Dividend (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Debt Instrument Redemption Summary	If redeemed during the 12-month period beginning March 9: Year Redemption Price 2017 106% 2018 105 2019 104 2020 103 2021 102 2022 and thereafter 100

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Summary of Segment Information	Summarized segment information is as follows: For the Quarter Ended September 30, 2017 (In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 384,078 $ 147,578 $ 32,488 $ (13,781 ) $ 550,363 Cost of goods sold 340,191 120,021 24,111 (13,061 ) 471,262 Depreciation and amortization 5,290 1,845 636 495 8,266 Selling, general, and administrative expense 17,873 2,667 2,312 10,424 33,276 Operating income 20,724 23,045 5,429 (11,639 ) 37,559 Interest expense (5,237 ) Other (expense) income, net (458 ) Income before income taxes $ 31,864 Segment Information (continued): For the Quarter Ended October 1, 2016 (In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 351,557 $ 131,350 $ 30,003 $ (6,326 ) $ 506,584 Cost of goods sold 301,867 107,512 22,210 (6,921 ) 424,668 Depreciation and amortization 5,905 1,964 612 535 9,016 Selling, general, and administrative expense 16,647 3,125 2,357 10,284 32,413 Asset impairments 3,000 — — — 3,000 Operating income 24,138 18,749 4,824 (10,224 ) 37,487 Interest expense (1,830 ) Other income, net 120 Income before income taxes $ 35,777 For the Nine Months Ended September 30, 2017 ( In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 1,205,697 $ 451,919 $ 103,403 $ (18,470 ) $ 1,742,549 Cost of goods sold 1,049,098 377,036 77,124 (19,258 ) 1,484,000 Depreciation and amortization 16,223 5,647 1,880 1,466 25,216 Selling, general, and administrative expense 54,293 8,761 7,244 32,655 102,953 Asset impairments 411 — — — 411 Operating income 85,672 60,475 17,155 (33,333 ) 129,969 Interest expense (14,210 ) Other income, net 324 Income before income taxes $ 116,083 Segment Information (continued): For the Nine Months Ended October 1, 2016 ( In thousands) Piping Systems Industrial Metals Climate Corporate and Eliminations Total Net sales $ 1,109,109 $ 393,608 $ 92,068 $ (11,321 ) $ 1,583,464 Cost of goods sold 949,015 321,615 68,363 (11,623 ) 1,327,370 Depreciation and amortization 17,341 6,219 1,829 1,608 26,997 Selling, general, and administrative expense 51,497 9,989 7,336 33,885 102,707 Asset impairments 3,000 — — — 3,000 Operating income 88,256 55,785 14,540 (35,191 ) 123,390 Interest expense (5,370 ) Other income, net 880 Income before income taxes $ 118,900

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Inventories	(In thousands) September 30, December 31, 2016 Raw materials and supplies $ 77,743 $ 57,387 Work-in-process 47,651 42,227 Finished goods 165,090 149,288 Valuation reserves (6,370 ) (6,889 ) Inventories $ 284,114 $ 242,013

Derivative Instruments and He25

Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments Designated as Cash Flow Hedges Reflected in the Financial Statements	The following table summarizes the location and fair value of the derivative instruments and disaggregates the net derivative assets and liabilities into gross components on a contract-by-contract basis: Asset Derivatives Liability Derivatives Fair Value Fair Value (In thousands) Balance Sheet Location September 30, 2017 December 31, 2016 Balance Sheet Location September 30, 2017 December 31, 2016 Commodity contracts - gains Other current assets $ 203 $ 1,013 Other current liabilities $ 796 $ 564 Commodity contracts - losses Other current assets (120 ) (148 ) Other current liabilities (1,770 ) (920 ) Interest rate swap Other current assets — — Other current liabilities (49 ) (787 ) Total derivatives (1) $ 83 $ 865 $ (1,023 ) $ (1,143 ) (1) Does not include the impact of cash collateral provided to counterparties.
Schedule of Fair Value Hedges	The following tables summarize the effects of derivative instruments on the Company’s Condensed Consolidated Statements of Income: For the Quarter Ended For the Nine Months Ended (In thousands) Location September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Fair value hedges: Gain (loss) on commodity contracts (qualifying) Cost of goods sold $ — $ (37 ) $ — $ (420 ) Gain on hedged item - inventory Cost of goods sold — 32 — 382 Undesignated derivatives: (Loss) gain on commodity contracts (nonqualifying) Cost of goods sold (3,083 ) 855 (3,506 ) 2,676
Summary of Activities Related to Derivative Instruments Classified as Cash Flow Hedges	The following tables summarize amounts recognized in and reclassified from AOCI during the period: For the Quarter Ended September 30, 2017 (In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (541 ) Cost of goods sold $ 237 Interest rate swap — Interest expense 149 Other 23 Other — Total $ (518 ) Total $ 386 Derivative Instruments and Hedging Activities (continued): For the Quarter Ended October 1, 2016 (In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (1,434 ) Cost of goods sold $ 814 Interest rate swap 457 Interest expense 58 Other (32 ) Other — Total $ (1,009 ) Total $ 872 For the Nine Months Ended September 30, 2017 ( In thousands) (Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ (1,354 ) Cost of goods sold $ 913 Interest rate swap — Interest expense 447 Other 179 Other — Total $ (1,175 ) Total $ 1,360 For the Nine Months Ended October 1, 2016 ( In thousands) Gain (Loss) Recognized in AOCI (Effective Portion), Net of Tax Classification Gains (Losses) (Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax Cash flow hedges: Commodity contracts $ 1,903 Cost of goods sold $ (477 ) Interest rate swap (128 ) Interest expense 186 Other (329 ) Other — Total $ 1,446 Total $ (291 )

Investment in Unconsolidated 26

Investment in Unconsolidated Affiliates (Tables)	9 Months Ended
	Sep. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Summarized Financial Information Derived From the Company's Equity Method Investee's Consolidated Financial Statements	The following tables present summarized financial information derived from the Company’s equity method investees’ combined consolidated financial statements, which are prepared in accordance with U.S. GAAP. September 30, December 31, 2016 Current assets $ 251,188 $ 244,323 Noncurrent assets 132,000 130,400 Current liabilities 177,110 148,806 Noncurrent liabilities 59,334 71,681 For the Quarter Ended For the Nine Months Ended (In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Net sales $ 148,400 $ 146,700 $ 407,300 $ 437,200 Gross profit 21,500 22,200 56,700 59,700 Net (loss) income (788 ) 2,244 (3,492 ) 6,097

Benefit Plans (Tables)

Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2017
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Benefit Cost (Income)	The components of net periodic benefit cost (income) are as follows: For the Quarter Ended For the Nine Months Ended (In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Pension benefits: Service cost $ 35 $ 180 $ 106 $ 540 Interest cost 1,659 1,973 4,977 5,917 Expected return on plan assets (2,184 ) (2,466 ) (6,552 ) (7,398 ) Amortization of net loss 536 760 1,608 2,280 Net periodic benefit cost $ 46 $ 447 $ 139 $ 1,339 Other benefits: Service cost $ 54 $ 61 $ 163 $ 183 Interest cost 147 153 442 458 Amortization of prior service credit (225 ) (224 ) (676 ) (672 ) Amortization of net gain (10 ) (9 ) (30 ) (27 ) Net periodic benefit income $ (34 ) $ (19 ) $ (101 ) $ (58 )

Accumulated Other Comprehensi28

Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Changes in AOCI by Component, Net of Taxes and Noncontrolling Interest	The following table provides changes in AOCI by component, net of taxes and noncontrolling interests (amounts in parentheses indicate debits to AOCI): For the Nine Months Ended September 30, 2017 (In thousands) Cumulative Translation Adjustment Unrealized (Loss) Gain on Derivatives Pension/OPEB Liability Adjustment Unrealized Gain (Loss) on Equity Securities Attributable to Unconsol. Affiliates Total Balance as of December 31, 2016 $ (49,965 ) $ (300 ) $ (23,046 ) 380 $ 5,975 $ (66,956 ) Other comprehensive income (loss) before reclassifications 18,209 (1,175 ) (1,309 ) (1 ) (1,086 ) 14,638 Amounts reclassified from AOCI (3,777 ) 1,360 737 (379 ) — (2,059 ) Net current-period other comprehensive income (loss) 14,432 185 (572 ) (380 ) (1,086 ) 12,579 Balance as of September 30, 2017 $ (35,533 ) $ (115 ) $ (23,618 ) — $ 4,889 $ (54,377 ) For the Nine Months Ended October 1, 2016 (In thousands) Cumulative Translation Adjustment Unrealized (Loss) Gain on Derivatives Pension/OPEB Liability Adjustment Unrealized Gain on Equity Securities Attributable to Unconsol. Affiliates Total Balance as of December 26, 2015 $ (24,773 ) $ (2,009 ) $ (28,429 ) 221 $ — $ (54,990 ) Other comprehensive (loss) income before reclassifications (14,638 ) 1,446 2,258 77 6,550 (4,307 ) Amounts reclassified from AOCI — (291 ) 1,187 — — 896 Net current-period other comprehensive (loss) income (14,638 ) 1,155 3,445 77 6,550 (3,411 ) Balance as of October 1, 2016 $ (39,411 ) $ (854 ) $ (24,984 ) 298 $ 6,550 $ (58,401 )
Reclassification Adjustments Out of AOCI	Reclassification adjustments out of AOCI were as follows: Amount reclassified from AOCI For the Quarter Ended For the Nine Months Ended ( In thousands) September 30, 2017 October 1, 2016 September 30, 2017 October 1, 2016 Affected line item Unrealized losses (gains) on derivatives: Commodity contracts $ 223 $ 848 $ 1,247 $ (1,023 ) Cost of goods sold Interest rate swap 232 91 696 291 Interest expense (69 ) (67 ) (583 ) 441 Income tax (benefit) expense $ 386 $ 872 $ 1,360 $ (291 ) Net of tax and noncontrolling interests Amortization of net loss and prior service cost on employee benefit plans $ 301 $ 527 $ 902 $ 1,581 Selling, general, and administrative (55 ) (132 ) (165 ) (394 ) Income tax benefit $ 246 $ 395 $ 737 $ 1,187 Net of tax and noncontrolling interests Sale of available-for-sale securities $ — $ — $ (611 ) $ — Other income $ — $ — $ 232 $ — Income tax expense $ — $ — $ (379 ) $ — Net of tax and noncontrolling interests Gain recognized upon sale of business $ — $ — $ (3,777 ) $ — Selling, general, and administrative $ — $ — $ — $ — Income tax expense $ — $ — $ (3,777 ) $ — Net of tax and noncontrolling interests

Noncontrolling Interests (Table

Noncontrolling Interests (Tables)	9 Months Ended
	Sep. 30, 2017
Noncontrolling Interest [Abstract]
Schedule of Noncontrolling Interests	(In thousands) Noncontrolling Interests Balance as of December 31, 2016 $ 37,753 Sale of Mueller-Xingrong (23,712 ) Dividends paid to noncontrolling interests (2,909 ) Net income attributable to noncontrolling interests 1,164 Other comprehensive income attributable to noncontrolling interests, net of tax: Foreign currency translation 838 Balance as of September 30, 2017 $ 13,134

Earnings per Common Share (Deta

Earnings per Common Share (Details) - shares shares in Thousands	3 Months Ended
	Sep. 30, 2017	Oct. 01, 2016
Earnings Per Share [Abstract]
Stock-based awards excluded from the computation of diluted earnings per share (in shares)	52	218

Special Dividend - Additional I

Special Dividend - Additional Information (Details) $ / shares in Units, $ in Millions	Mar. 09, 2017USD ($)$ / shares
Equity [Abstract]
Cash dividend (in dollars per share) | $ / shares	$ 3
Cash dividend, subordinated debentures (in dollars per share) | $ / shares	$ 5
Interest rate of subordinated debentures	6.00%
Decrease in stockholders' equity	$ 458.7
Increase in long-term debt	284.5
Decrease in cash	$ 174.2

Special Dividend - Debt Instrum

Special Dividend - Debt Instrument Redemption (Details) - Subordinated Debt [Member]	9 Months Ended
	Sep. 30, 2017
2017 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	106.00%
2018 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	105.00%
2019 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	104.00%
2020 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	103.00%
2021 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	102.00%
2022 and thereafter
Debt Instrument, Redemption [Line Items]
Redemption price (percent)	100.00%

Acquisitions and Dispositions -

Acquisitions and Dispositions - Acquisitions (Details) - USD ($) $ in Thousands	May 31, 2017	Apr. 26, 2016	Sep. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Noncontrolling interests			$ 13,134	$ 37,753
Pexcor/Heatlink [Member]
Business Acquisition [Line Items]
Consideration transferred net of working capital adjustments	$ 18,500
Cash payment to acquire business	16,300
Maximum contingent consideration liability	2,200
Fair value of assets acquired	10,400
Fair value of inventories acquired	4,500
Fair value of accounts receivable acquired	2,800
Fair value of property, plant and equipment acquired	2,000
Fair value of other current assets acquired	500
Fair value of other assets acquired	600
Fair value of liabilities acquired	4,300
Fair value of accounts payable acquired	3,600
Fair value of other current liabilities acquired	400
Fair value of other liabilities acquired	300
Allocation to non-deductible goodwill and intangible assets	$ 12,400
Jungwoo Metal Ind. Co., LTD [Member]
Business Acquisition [Line Items]
Fair value of assets acquired		$ 49,000
Fair value of inventories acquired		17,600
Fair value of accounts receivable acquired		5,600
Fair value of property, plant and equipment acquired		24,200
Fair value of other current assets acquired		1,400
Fair value of liabilities acquired		17,900
Fair value of accounts payable acquired		7,300
Fair value of other current liabilities acquired		500
Fair value of other liabilities acquired		600
Allocation to non-deductible goodwill and intangible assets		$ 1,000
Ownership percentage		60.00%
Payments to acquire interest in joint venture		$ 20,500
Fair value of deferred tax assets acquired		200
Fair value of long-term debt acquired		8,700
Fair value of pension liabilities acquired		800
Noncontrolling interests		$ 11,600

Acquisitions and Dispositions34

Acquisitions and Dispositions - Dispositions (Details) - USD ($) $ in Thousands	Jun. 21, 2017	Sep. 30, 2017	Oct. 01, 2016	Jul. 01, 2017	Sep. 30, 2017	Oct. 01, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net income (loss)		$ (788)	$ 2,244		$ (3,492)	$ 6,097
Gain on sale of business					1,491	0
Mueller-Xingrong [Member] | Disposed of by sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of interest in joint venture	$ 18,300
Assets disposed of	56,700
Liabilities disposed of	36,200
Cumulative translation gain as a result of sale	$ 3,800
Gain on sale of business				$ 1,500
Mueller-Xingrong [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage	50.50%
Net sales					67,300	69,600
Net income (loss)					$ (9)	$ 426

Segment Information - Summary o

Segment Information - Summary of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Summary of segment information [Abstract]
Net sales	$ 550,363	$ 506,584	$ 1,742,549	$ 1,583,464
Cost of goods sold	471,262	424,668	1,484,000	1,327,370
Depreciation and amortization	8,266	9,016	25,216	26,997
Selling, general, and administrative expense	33,276	32,413	102,953	102,707
Asset impairments	0	3,000	411	3,000
Operating income	37,559	37,487	129,969	123,390
Interest expense	(5,237)	(1,830)	(14,210)	(5,370)
Other (expense) income, net	(458)	120	324	880
Income before income taxes	31,864	35,777	116,083	118,900
Piping Systems [Member]
Summary of segment information [Abstract]
Asset impairments		3,000		3,000
Operating Segments [Member] | Piping Systems [Member]
Summary of segment information [Abstract]
Net sales	384,078	351,557	1,205,697	1,109,109
Cost of goods sold	340,191	301,867	1,049,098	949,015
Depreciation and amortization	5,290	5,905	16,223	17,341
Selling, general, and administrative expense	17,873	16,647	54,293	51,497
Asset impairments			411
Operating income	20,724	24,138	85,672	88,256
Operating Segments [Member] | Industrial Metals [Member]
Summary of segment information [Abstract]
Net sales	147,578	131,350	451,919	393,608
Cost of goods sold	120,021	107,512	377,036	321,615
Depreciation and amortization	1,845	1,964	5,647	6,219
Selling, general, and administrative expense	2,667	3,125	8,761	9,989
Asset impairments		0	0	0
Operating income	23,045	18,749	60,475	55,785
Operating Segments [Member] | Climate [Member]
Summary of segment information [Abstract]
Net sales	32,488	30,003	103,403	92,068
Cost of goods sold	24,111	22,210	77,124	68,363
Depreciation and amortization	636	612	1,880	1,829
Selling, general, and administrative expense	2,312	2,357	7,244	7,336
Asset impairments		0	0	0
Operating income	5,429	4,824	17,155	14,540
Corporate and Eliminations [Member]
Summary of segment information [Abstract]
Net sales	(13,781)	(6,326)	(18,470)	(11,321)
Cost of goods sold	(13,061)	(6,921)	(19,258)	(11,623)
Depreciation and amortization	495	535	1,466	1,608
Selling, general, and administrative expense	10,424	10,284	32,655	33,885
Asset impairments		0	0	0
Operating income	$ (11,639)	$ (10,224)	$ (33,333)	$ (35,191)

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 77,743	$ 57,387
Work-in-process	47,651	42,227
Finished goods	165,090	149,288
Valuation reserves	(6,370)	(6,889)
Inventories	$ 284,114	$ 242,013

Derivative Instruments and He37

Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($)	Jan. 12, 2015	Sep. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Restricted cash in other current assets as collateral related to open derivative contracts		$ 3,000,000	$ 1,400,000
Commodity Contracts [Member]
Derivative [Line Items]
Deferred net losses, net of tax, included in AOCI		133,000
Interest Rate Swap [Member]
Derivative [Line Items]
Deferred net losses, net of tax, included in AOCI		$ 107,000
Period of interest rate swap	2 years
Notional amount	$ 200,000,000
Interest rate swap, fixed interest rate	1.40%
Term loan facility, all-in fixed interest rate		2.98%
Cash Flow Hedging [Member] | Commodity Contracts [Member] | Long [Member]
Derivative [Line Items]
Open option contracts written, at fair value		$ 11,800,000
Time period for open copper future contract purchases		15 months
Fair value of future contracts with loss position		$ 165,000
Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Long [Member]
Derivative [Line Items]
Fair value of future contracts with loss position		49,000
Fair Value Hedging [Member] | Commodity Contracts [Member] | Short [Member]
Derivative [Line Items]
Fair value of future contracts with loss position		726,000
Open future contracts to sell copper		$ 57,700,000
Time period for open copper future contract sales		6 months

Derivative Instruments and He38

Derivative Instruments and Hedging Activities - Summary of Location and Fair Value (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total derivative assets	$ 83	$ 865
Total derivative liabilities	(1,023)	(1,143)
Other Current Assets [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Other current assets: Gain positions	203	1,013
Other current assets: Loss positions	(120)	(148)
Other Current Assets [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Other current assets: Loss positions	0	0
Other Current Liabilities [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Gain positions	796	564
Other current liability: Loss positions	(1,770)	(920)
Other Current Liabilities [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Loss positions	$ (49)	$ (787)

Derivative Instruments and He39

Derivative Instruments and Hedging Activities - Effects of Derivative Instruments on Statements of Income (Details) - Cost of Goods Sold [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Commodity Contracts [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on the derivatives in designated and qualifying fair value hedges	$ 0	$ (37)	$ 0	$ (420)
Commodity Contracts [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) gain on commodity contracts (nonqualifying)	(3,083)	855	(3,506)	2,676
Inventories [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on the derivatives in designated and qualifying fair value hedges	$ 0	$ 32	$ 0	$ 382

Derivative Instruments and He40

Derivative Instruments and Hedging Activities - Amounts Recognized in and Reclassified from AOCI (Details) - Cash Flow Hedging [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax	$ (518)	$ (1,009)	$ (1,175)	$ 1,446
(Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax	386	872	1,360	(291)
Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax	(541)	(1,434)	(1,354)	1,903
Commodity Contracts [Member] | Cost of Goods Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax	237	814	913	(477)
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax	0	457	0	(128)
Interest Rate Swap [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax	149	58	447	186
Other [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Loss) Gain Recognized in AOCI (Effective Portion), Net of Tax	23	(32)	179	(329)
(Gain) Loss Reclassified from AOCI (Effective Portion), Net of Tax	$ 0	$ 0	$ 0	$ 0

Investment in Unconsolidated 41

Investment in Unconsolidated Affiliates - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017
Schedule of Equity Method Investments [Line Items]
Net loss	$ 788	$ (2,244)	$ 3,492	$ (6,097)
Tecumseh Products Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in the joint venture, ownership percentage	50.00%		50.00%		50.00%
Gain resulted from the allocation of the purchase price included in Joint Venture's net income				17,100
Restructuring and impairment charges				5,300
Net loss				$ 5,700
Second Unconsolidated Affiliate [Member]
Schedule of Equity Method Investments [Line Items]
Interest in the joint venture, ownership percentage	50.00%		50.00%		50.00%
Cayan Ventures and Bahrain Mumtalakat Holding Company [Member]
Schedule of Equity Method Investments [Line Items]
Interest in the joint venture, ownership percentage	40.00%		40.00%		40.00%
Cash invested to acquire joint venture interest					$ 3,900

Investment in Unconsolidated 42

Investment in Unconsolidated Affiliates - Summarized Financial Information Derived from Equity Method Investees' Consolidated Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2016
Balance sheet data [Abstract]
Current assets	$ 251,188		$ 251,188		$ 244,323
Noncurrent assets	132,000		132,000		130,400
Current liabilities	177,110		177,110		148,806
Noncurrent liabilities	59,334		59,334		$ 71,681
Income statement data [Abstract]
Net sales	148,400	$ 146,700	407,300	$ 437,200
Gross profit	21,500	22,200	56,700	59,700
Net (loss) income	$ (788)	$ 2,244	$ (3,492)	$ 6,097

Benefit Plans (Details)

Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Pension Benefits [Member]
Components of net periodic benefit cost (income) [Abstract]
Service cost	$ 35	$ 180	$ 106	$ 540
Interest cost	1,659	1,973	4,977	5,917
Expected return on plan assets	(2,184)	(2,466)	(6,552)	(7,398)
Amortization of net (gain) loss	536	760	1,608	2,280
Net periodic benefit income	46	447	139	1,339
Other Benefits [Member]
Components of net periodic benefit cost (income) [Abstract]
Service cost	54	61	163	183
Interest cost	147	153	442	458
Amortization of prior service credit	(225)	(224)	(676)	(672)
Amortization of net (gain) loss	(10)	(9)	(30)	(27)
Net periodic benefit income	$ (34)	$ (19)	$ (101)	$ (58)

Commitments and Contingencies -

Commitments and Contingencies - Lead Refinery Site (Details) - Lead Refinery Site [Member] $ in Millions	1 Months Ended	9 Months Ended
	Sep. 30, 2014USD ($)property	Sep. 30, 2017USD ($)	Sep. 27, 2014potentially_responsible_party	Jul. 17, 2009potentially_responsible_party
Site Contingency [Line Items]
Financial guarantee		$ 1
Non operating Properties [Member]
Site Contingency [Line Items]
Estimated number of years until mitigation resolution		20 years
Number of parties involved in settlement negotiations | potentially_responsible_party			2	2
EPA's estimated cost of site remediation	$ 26
Number of surrounding properties | property	300
Non operating Properties [Member] | Minimum [Member]
Site Contingency [Line Items]
Mitigation estimates		$ 2.1
Non operating Properties [Member] | Maximum [Member]
Site Contingency [Line Items]
Mitigation estimates		$ 4.7

Commitments and Contingencies45

Commitments and Contingencies - Additional Information (Details) $ in Millions	Oct. 05, 2016individual	Sep. 30, 2017USD ($)
Loss Contingencies [Line Items]
Term of guarantees		1 year
Payments required to be made under guarantees, maximum | $		$ 8.4
Equal Employment Opportunity Commission Matter [Member]
Loss Contingencies [Line Items]
Number of identified individuals	20
Number of unidentified individuals	150

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Income Tax Disclosure [Abstract]
Effective tax rate	27.00%	30.00%	29.00%	33.00%
Reduction for U.S. production activities	$ 0.6	$ 0.6	$ 2.4	$ 2.5
Effect of foreign adjustments	1.6	1	4.6	3.5
Provision for state income taxes, net of federal benefits		0.6	1.7	2.3
Tax benefit of equity compensation deductions	$ 0.5	$ 0.8	2.2	0.8
Impact of investments in unconsolidated affiliates			$ 0.9	$ 1.2

Accumulated Other Comprehensi47

Accumulated Other Comprehensive Income - Changes by Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			$ 936,437
Total other comprehensive income (loss), net	$ 6,080	$ 1,466	13,417	$ (4,374)
Ending balance	530,037		530,037
Total [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			(66,956)	(54,990)
Other comprehensive income (loss) before reclassifications			14,638	(4,307)
Amounts reclassified from AOCI			(2,059)	896
Total other comprehensive income (loss), net			12,579	(3,411)
Ending balance	(54,377)	(58,401)	(54,377)	(58,401)
Cumulative Translation Adjustment [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			(49,965)	(24,773)
Other comprehensive income (loss) before reclassifications			18,209	(14,638)
Amounts reclassified from AOCI			(3,777)	0
Total other comprehensive income (loss), net			14,432	(14,638)
Ending balance	(35,533)	(39,411)	(35,533)	(39,411)
Unrealized (Loss) Gain on Derivatives [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			(300)	(2,009)
Other comprehensive income (loss) before reclassifications			(1,175)	1,446
Amounts reclassified from AOCI			1,360	(291)
Total other comprehensive income (loss), net			185	1,155
Ending balance	(115)	(854)	(115)	(854)
Pension/OPEB Liability Adjustment [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			(23,046)	(28,429)
Other comprehensive income (loss) before reclassifications			(1,309)	2,258
Amounts reclassified from AOCI			737	1,187
Total other comprehensive income (loss), net			(572)	3,445
Ending balance	(23,618)	(24,984)	(23,618)	(24,984)
Unrealized Gain (Loss) on Equity Securities [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			380	221
Other comprehensive income (loss) before reclassifications			(1)	77
Amounts reclassified from AOCI			(379)	0
Total other comprehensive income (loss), net			(380)	77
Ending balance	0	298	0	298
Attributable to Unconsolidated Affiliates [Member]
Changes in accumulated other comprehensive income [Roll Forward]
Beginning balance			5,975	0
Other comprehensive income (loss) before reclassifications			(1,086)	6,550
Amounts reclassified from AOCI			0	0
Total other comprehensive income (loss), net			(1,086)	6,550
Ending balance	$ 4,889	$ 6,550	$ 4,889	$ 6,550

Accumulated Other Comprehensi48

Accumulated Other Comprehensive Income - Reclassification Adjustments Out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	$ 471,262	$ 424,668	$ 1,484,000	$ 1,327,370
Interest expense	5,237	1,830	14,210	5,370
Income tax (benefit) expense	8,716	10,837	33,295	38,963
Selling, general, and administrative expense	33,276	32,413	102,953	102,707
Other income	458	(120)	(324)	(880)
Net income attributable to Mueller Industries, Inc.	(22,258)	(25,978)	(79,878)	(82,405)
Unrealized losses (gains) on derivatives [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of goods sold	223	848	1,247	(1,023)
Interest expense	232	91	696	291
Income tax (benefit) expense	(69)	(67)	(583)	441
Net income attributable to Mueller Industries, Inc.	386	872	1,360	(291)
Amortization of net loss and prior service cost on employee benefit plans [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (benefit) expense	(55)	(132)	(165)	(394)
Selling, general, and administrative expense	301	527	902	1,581
Net income attributable to Mueller Industries, Inc.	246	395	737	1,187
Sale of available-for-sale securities [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax (benefit) expense	0	0	232	0
Other income	0	0	(611)	0
Net income attributable to Mueller Industries, Inc.	0	0	(379)	0
Gain recognized upon sale of business [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	0	0	(3,777)	0
Net income attributable to Mueller Industries, Inc.	$ 0	$ 0	$ (3,777)	$ 0

Noncontrolling Interests (Detai

Noncontrolling Interests (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance as of December 31, 2016			$ 37,753
Sale of Mueller-Xingrong			(23,712)
Dividends paid to noncontrolling interests			(2,909)
Net income attributable to noncontrolling interests	$ 496	$ 84	1,164	$ 581
Other comprehensive income attributable to noncontrolling interests, net of tax:
Foreign currency translation			838
Balance as of September 30, 2017	$ 13,134		$ 13,134