Superior Industries International (SUP) 10-K 7 Mar 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Feb. 28, 2019	Jun. 30, 2018
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Trading Symbol	SUP
Entity Registrant Name	SUPERIOR INDUSTRIES INTERNATIONAL INC
Entity Central Index Key	95,552
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		25,019,237
Entity Public Float			$ 447,709,967
Smaller Reporting Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false

Consolidated Income Statements

Consolidated Income Statements - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Income Statement [Abstract]
NET SALES	$ 1,501,827	$ 1,108,055	$ 732,677
Cost of sales:
Cost of sales	1,338,300	1,005,020	645,015
Restructuring costs		138	1,458
Total cost of sales	1,338,300	1,005,158	646,473
GROSS PROFIT	163,527	102,897	86,204
Selling, general and administrative expenses	77,722	81,379	31,602
INCOME FROM OPERATIONS	85,805	21,518	54,602
Interest (expense) income, net	(50,097)	(40,004)	245
Other (expense) income, net	(6,936)	13,188	(126)
Change in fair value of redeemable preferred stock embedded derivative liability	3,480	6,164
CONSOLIDATED INCOME BEFORE INCOME TAXES	32,252	866	54,721
Income tax provision	(6,291)	(6,875)	(13,340)
CONSOLIDATED NET INCOME (LOSS)	25,961	(6,009)	41,381
Less: Net (income) attributable to non-controlling interest		(194)
NET INCOME (LOSS) ATTRIBUTABLE TO SUPERIOR	$ 25,961	$ (6,203)	$ 41,381
EARNINGS (LOSS) PER SHARE ATTRIBUTABLE TO SUPERIOR - BASIC	$ 0.29	$ (1.01)	$ 1.63
EARNINGS (LOSS) PER SHARE ATTRIBUTABLE TO SUPERIOR - DILUTED	$ 0.29	$ (1.01)	$ 1.62

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss) attributable to Superior	$ 25,961	$ (6,203)	$ 41,381
Other comprehensive (loss) income, net of tax:
Foreign currency translation (loss) gain	(23,924)	29,822	(16,904)
Change in unrecognized gains (losses) on derivative instruments:
Change in fair value of derivatives	7,221	14,067	(11,062)
Tax (provision) benefit	(1,928)	(6,464)	4,250
Change in unrecognized gains (losses) on derivative instruments, net of tax	5,293	7,603	(6,812)
Defined benefit pension plan:
Actuarial gains (losses) on pension obligation, net of curtailments and amortization	2,924	(1,931)	799
Tax (provision) benefit	(667)	310	(295)
Pension changes, net of tax	2,257	(1,621)	504
Other comprehensive (loss) income, net of tax	(16,374)	35,804	(23,212)
Comprehensive income attributable to Superior	$ 9,587	$ 29,601	$ 18,169

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 47,464	$ 46,360
Short-term investments	750	750
Accounts receivable, net	104,649	160,167
Inventories, net	175,578	173,999
Income taxes receivable	6,791	6,929
Other current assets	35,189	29,178
Total current assets	370,421	417,383
Property, plant and equipment, net	532,767	536,686
Non-current deferred income tax assets, net	42,105	54,302
Goodwill	291,434	304,805
Intangibles, net	168,369	203,473
Other non-current assets	46,520	34,603
Total assets	1,451,616	1,551,252
Current liabilities:
Accounts payable	107,274	118,424
Short-term debt	3,052	4,000
Accrued expenses	65,662	68,786
Income taxes payable	2,475	3,849
Total current liabilities	178,463	195,059
Long-term debt (less current portion)	661,426	679,552
Embedded derivative liability	3,134	4,685
Non-current income tax liabilities	9,046	5,731
Non-current deferred income tax liabilities, net	18,664	28,539
Other non-current liabilities	49,306	47,269
Commitments and contingent liabilities (Note 22)
Mezzanine equity:
Preferred stock, $0.01 par value Authorized - 1,000,000 shares; issued and outstanding - 150,000 shares outstanding at December 31, 2018 and December 31, 2017	144,463	144,694
European non-controlling redeemable equity	13,849
Shareholders' equity:
Common stock, $0.01 par value Authorized - 100,000,000 shares Issued and outstanding - 25,019,237 and 24,917,025 shares at December 31, 2018 and December 31, 2017)	87,723	89,755
Accumulated other comprehensive loss	(105,495)	(89,121)
Retained earnings	391,037	393,146
Superior shareholders' equity	373,265	393,780
Non-controlling interests		51,943
Total shareholders' equity	373,265	445,723
Total liabilities, mezzanine equity and shareholders' equity	$ 1,451,616	$ 1,551,252

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	150,000	150,000
Preferred stock, shares outstanding	150,000	150,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	25,019,237	24,917,025
Common stock, shares outstanding	25,019,237	24,917,025

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Unrecognized Gains (Losses) on Derivative Instruments	Pension Obligations	Cumulative Translation Adjustment	Retained Earnings	Non-controlling Interest
Beginning of period at Dec. 27, 2015	$ 413,912	$ 88,108	$ (9,289)	$ (4,140)	$ (88,284)	$ 427,517
Beginning of the period (in shares) at Dec. 27, 2015		26,098,895
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)	41,381					41,381
Change in unrecognized gains/losses on derivative instruments, net of tax	(6,812)		(6,812)
Change in employee benefit plans, net of taxes	504			504
Net foreign currency translation adjustment	(16,904)				(16,904)
Stock options exercised	1,641	$ 1,641
Stock options exercised (in shares)		86,908
Common stock issued, net of shares withheld for employee taxes	0	$ 0	$ 0	$ 0	$ 0	$ 0
Common stock issued, net of shares withheld for employee taxes (in shares)		(1,165)
Stock-based compensation	$ 3,618	$ 3,618
Stock-based compensation (in shares)	0	0	0	0	0	0
Tax impact of stock options	$ 92	$ 92
Common stock repurchased	(20,719)	$ (3,543)				$ (17,176)
Common stock repurchased (in shares)		(1,040,688)
Cash dividends declared	(18,487)					(18,487)
End of period at Dec. 25, 2016	398,226	$ 89,916	$ (16,101)	$ (3,636)	$ (105,188)	433,235
End of the period (in shares) at Dec. 25, 2016		25,143,950
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)	(6,009)					(6,203)	$ 194
Change in unrecognized gains/losses on derivative instruments, net of tax	7,603		7,603
Change in employee benefit plans, net of taxes	(1,621)			(1,621)
Net foreign currency translation adjustment	34,089				29,822		4,267
Stock options exercised	41	$ 41
Stock options exercised (in shares)		2,000
Common stock issued, net of shares withheld for employee taxes	0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Common stock issued, net of shares withheld for employee taxes (in shares)		(13,084)
Stock-based compensation	$ 889	$ 889
Stock-based compensation (in shares)	0	0	0	0	0	0	0
Common stock repurchased	$ (5,014)	$ (777)				$ (4,237)
Common stock repurchased (in shares)		(215,841)
Cash dividends declared	(10,737)					(10,737)
Redeemable preferred dividend and accretion	(18,912)					(18,912)
Non-controlling interest	63,200						$ 63,200
Uniwheels additional tenders	(16,032)	$ (314)					(15,718)
End of period at Dec. 31, 2017	$ 445,723	$ 89,755	$ (8,498)	$ (5,257)	$ (75,366)	393,146	51,943
End of the period (in shares) at Dec. 31, 2017	24,917,025	24,917,025
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)	$ 25,961					25,961
Change in unrecognized gains/losses on derivative instruments, net of tax	5,293		5,293
Change in employee benefit plans, net of taxes	2,257			2,257
Net foreign currency translation adjustment	(23,924)				(23,924)
Stock options exercised	$ 68	$ 68
Stock options exercised (in shares)	4,500	4,500
Common stock issued, net of shares withheld for employee taxes	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Common stock issued, net of shares withheld for employee taxes (in shares)		97,712
Stock-based compensation	$ 1,525	$ 1,525
Stock-based compensation (in shares)	0	0	0	0	0	0	0
Cash dividends declared	$ (9,353)					$ (9,353)
Redeemable preferred dividend and accretion	(32,462)					(32,462)
Preferred stock modification	$ 15,257					$ 15,257
Preferred stock modification ( in shares)	0	0	0	0	0	0	0
Reclassification to European non-controlling redeemable equity	$ (51,943)						$ (51,943)
Adjust European non-controlling redeemable equity to redemption value	(3,625)	$ (3,625)
Dividends accrued	(1,512)					$ (1,512)
End of period at Dec. 31, 2018	$ 373,265	$ 87,723	$ (3,205)	$ (3,000)	$ (99,290)	$ 391,037
End of the period (in shares) at Dec. 31, 2018	25,019,237	25,019,237

Consolidated Statements of Sh_2

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per share	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.18	$ 0.36	$ 0.45	$ 0.72

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 25,961	$ (6,009)	$ 41,381
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	95,056	69,335	34,261
Income tax, non-cash changes	(1,048)	(3,395)	(4,669)
Stock-based compensation	2,131	2,576	3,618
Debt amortization	3,868	7,328
Other non-cash items	5,733	1,133	812
Accounts receivable	42,829	4,599	8,043
Inventories	(6,125)	(1,264)	(22,339)
Other assets and liabilities	(7,732)	(8,214)	6,244
Accounts payable	(9,132)	1,411	15,880
Income taxes	4,575	(3,790)	(4,740)
NET CASH PROVIDED BY OPERATING ACTIVITIES	156,116	63,710	78,491
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant and equipment	(77,697)	(70,937)	(39,575)
Acquisition of Uniwheels, net of cash acquired		(706,733)
Proceeds from sales and maturities of investments	600		200
Proceeds from sales of fixed assets		56	4,337
NET CASH USED IN INVESTING ACTIVITIES	(77,097)	(777,614)	(35,038)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt		975,571
Proceeds from issuance of redeemable preferred shares		150,000
Debt repayment	(7,936)	(323,177)
Cash dividends paid	(28,816)	(19,473)	(18,340)
Purchase of non-controlling redeemable shares	(39,048)
Cash paid for common stock repurchase		(5,014)	(20,719)
Payments related to tax withholdings for stock-based compensation	(606)	(1,687)
Net decrease in short term debt		(10,877)
Proceeds from borrowings on revolving credit facility	324,450	71,750
Repayments of borrowings on revolving credit facility	(324,450)	(100,650)
Proceeds from exercise of stock options	68	41	1,641
Redeemable preferred shares issuance costs		(3,737)
Financing costs paid		(31,640)
Excess tax benefits from exercise of stock options			91
NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES	(76,338)	701,107	(37,327)
Effect of exchange rate changes on cash	(1,577)	1,371	(376)
Net increase (decrease) in cash and cash equivalents	1,104	(11,426)	5,750
Cash and cash equivalents at the beginning of the period	46,360	57,786	52,036
Cash and cash equivalents at the end of the period	$ 47,464	$ 46,360	$ 57,786

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE 1 - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Superior Industries International, Inc. (referred to herein as the “Company” or “we,” “us” and “our”) designs and manufactures aluminum wheels for sale to original equipment manufacturers (“OEMs”) and aftermarket customers. We are one of the largest suppliers of cast aluminum wheels to the world’s leading automobile and light truck manufacturers, with manufacturing operations in the United States, Mexico, Germany and Poland. Our OEM aluminum wheels are sold primarily for factory installation, as either standard equipment or optional equipment, on vehicle models manufactured by BMW-Mini, (Mercedes-Benz, Presentation of Consolidated Financial Statements The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions are eliminated in consolidation. Accounting estimates are an integral part of the consolidated financial statements. These estimates require the use of judgments and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses in the periods presented. We believe that the accounting estimates employed are appropriate and the resulting balances are reasonable; however, due to the inherent uncertainties in making estimates, actual results could differ from the original estimates, requiring adjustments to these balances in future periods. Cash and Cash Equivalents Cash and cash equivalents generally consist of cash, certificates of deposit, fixed deposits and money market funds with original maturities of three months or less. Certificates of deposit and fixed deposits whose original maturity is greater than three months and is one year or less are classified as short-term investments. At December 31, 2018 and 2017, certificates of deposit totaling $0.8 million were restricted in use (to collateralize letters of credit securing workers’ compensation obligations) and were classified as short-term investments on our consolidated balance sheet. Derivative Financial Instruments and Hedging Activities We account for our derivative instruments as either assets or liabilities and carry them at fair value. For derivative instruments that hedge the exposure to variability in expected future cash flows that are designated as cash flow hedges, the gain or loss on the derivative instrument (including changes in time value for forward contracts) is reported as a component of accumulated other comprehensive income or loss in shareholders’ equity and reclassified into income in the same period or periods during which the hedged transaction affects earnings. Derivatives that do not qualify or have not been designated as hedges are adjusted to fair value through current income. See Note 5, “Derivative Financial Instruments” for additional information pertaining to our derivative instruments. We enter into contracts to purchase certain commodities used in the manufacture of our products, such as aluminum, natural gas and other raw materials. These contracts are considered to be derivative instruments under U.S. GAAP; however, these purchase contracts are not accounted for as derivatives because they qualify for the normal purchase normal sale exemption. Cash Paid for Interest and Taxes and Non-Cash Cash paid for interest was $43.8 million, $24.3 million and $0.3 million for the years ended December 31, 2018, 2017 and 2016. Cash paid for income taxes was $6.5 million, $11.1 million and $21.9 million for the years ended December 31, 2018, 2017 and 2016. As of December 31, 2018, 2017 and 2016, $10.3 million, $15.1 million and $4.0 million, respectively, of equipment had been purchased but not yet paid for and are included in accounts payable and accrued expenses in our consolidated balance sheets. Accounts Receivable Accounts receivable primarily consists of amounts that are due and payable from our customers for the sale of aluminum wheels. We evaluate the collectability of receivables each reporting period and record an allowance for doubtful accounts representing our estimate of probable losses. Additions to the allowance are charged to bad debt expense reported in selling, general and administrative expense. Inventory Inventories, which are categorized as raw materials, work-in-process Property, Plant and Equipment Property, plant and equipment are carried at cost, less accumulated depreciation. The cost of additions, improvements and interest during construction, if any, are capitalized. Our maintenance and repair costs are charged to expense when incurred. Depreciation is calculated generally on the straight-line method based on the estimated useful lives of the assets. Classification Expected Useful Life Computer equipment 3 to 5 years Production machinery and technical equipment 3 to 20 years Buildings 15 to 50 years Other equipment, operating and office equipment 3 to 20 years When property, plant and equipment is replaced, retired or disposed of, the cost and related accumulated depreciation are removed and any resulting gain or loss is recorded as a component of cost of sales or other income or expense. Impairment of Long-Lived Assets The carrying amount of long-lived assets and finite-lived intangible assets to be held and used in the business is evaluated for impairment when events and circumstances warrant. If the carrying amount of a long-lived asset group is considered impaired, a loss is recorded based on the amount by which the carrying amount exceeds fair value. Fair value is determined primarily using anticipated cash flows. Impairment of Goodwill Goodwill is not amortized but is tested for impairment on at least an annual basis. Impairment testing is required more often than annually if an event or circumstance indicates that an impairment is more likely than not to have occurred. If the net book value of a reporting unit exceeds its fair value, an impairment loss is measured and recognized. We conduct our annual impairment testing as of December 31, 2018. Foreign Currency Transactions and Translation The assets and liabilities of foreign subsidiaries that use local currency as their functional currency are translated to U.S. dollars based on the current exchange rate prevailing at each balance sheet date and any resulting translation adjustments are included in accumulated other comprehensive income (loss). The assets and liabilities of foreign subsidiaries whose local currency is not their functional currency are remeasured from their local currency to their functional currency and then translated to U.S. dollars. Revenues and expenses are translated into U.S. dollars using the average exchange rates prevailing for each period presented. Gains and losses arising from foreign currency transactions and the effects of remeasurement discussed in the preceding paragraph are recorded in other income (expense), net. We had foreign currency transaction gains (losses) of ($1.0) million, $12.9 million, ($0.4) million in 2018, 2017 and 2016, respectively. Revenue Recognition On January 1, 2018, we adopted ASU 2014-09, The Company maintains long term business relationships with our OEM customers and aftermarket distributors; however, there are no definitive long-term volume commitments under these arrangements. Volume commitments are limited to near-term customer requirements authorized under purchase orders or production releases generally with delivery periods of less than a month. Sales do not involve any significant financing component since customer payment is generally due 40-60 At contract inception, the Company assesses goods and services promised in its contracts with customers and identifies a performance obligation for each promise to deliver a good or service (or bundle of goods or services) that is distinct. Principal performance obligations under our customer contracts consist of the manufacture and delivery of aluminum wheels, including production wheels, service wheels and replacement wheels. As a part of the manufacture of the wheels, we develop tooling necessary to produce the wheels. Accordingly, tooling costs, which are explicitly recoverable from our customers, are capitalized as preproduction costs and amortized to cost of sales over the average life of the vehicle wheel program. Similarly, customer reimbursement for tooling costs is deferred and amortized to net sales over the average life of the vehicle wheel program. In the normal course of business, the Company’s warranties are limited to product specifications and the Company does not accept product returns unless the item is defective as manufactured. Accordingly, warranty costs are treated as a cost of fulfillment subject to accrual, rather than a performance obligation. The Company establishes provisions for both estimated returns and warranties when revenue is recognized. In addition, the Company does not typically provide customers with the right to a refund but provides for product replacement. Prices allocated to production, service and replacement wheels are based on prices established in our customer purchase orders which represent the standalone selling price. Prices for service and replacement wheels are commensurate with production wheels with adjustment for any special packaging. In addition, prices are subject to retrospective adjustment for changes in commodity prices for certain raw materials, aluminum and silicon, as well as production efficiencies and wheel weight variations from specifications used in pricing. These price adjustments are treated as variable consideration. Customer tooling reimbursement is generally based on quoted prices or cost not to exceed quoted prices. We estimate variable consideration by using the “most likely” amount estimation approach. For commodity prices, initial estimates are based on the commodity index at contract inception. Changes in commodity prices are monitored and revenue is adjusted as changes in the commodity index occur. Prices incorporate the wheel weight price component based on product specifications. Weights are monitored, and prices are adjusted as variations arise. Price adjustments due to production efficiencies are generally recognized as and when negotiated with customers. Customer contract prices are generally adjusted quarterly to incorporate retroactive price adjustments. Under the Company’s policies, shipping costs are treated as a cost of fulfillment. In addition, as permitted under a practical expedient relating to disclosure of performance obligations, the Company does not disclose remaining performance obligations under its contracts since contract terms are substantially less than a year (generally less than one month). Our revenue recognition practices and related transactions and balances are further described in Note 3, “Revenue.” Research and Development Research and development costs (primarily engineering and related costs) are expensed as incurred and are included in cost of sales in the consolidated income statements. Amounts expensed during 2018, 2017 and 2016 were $5.7 million, $7.7 million and $3.8 million, respectively. Stock-Based Compensation We account for stock-based compensation using the estimated fair value recognition method. We recognize these compensation costs net of the applicable forfeiture rate on a straight-line basis for only those shares expected to vest over the requisite service period of the award, which is generally the vesting term of three years. We estimate the forfeiture rate based on our historical experience. See Note 20, “Stock-Based Compensation” for additional information concerning our stock-based compensation awards. Income Taxes We account for income taxes using the asset and liability method. The asset and liability method requires the recognition of deferred tax assets and liabilities for expected future tax consequences of temporary differences that currently exist between the tax basis and financial reporting basis of our assets and liabilities. We calculate current and deferred tax provisions based on estimates and assumptions that could differ from actual results reflected on the income tax returns filed during the following years. Adjustments based on filed returns are recorded when identified in the subsequent years. The effect on deferred taxes for a change in tax rates is recognized in income in the period that the tax rate change is enacted. In assessing the realizability of deferred tax assets, we consider whether it is more likely than not that some portion of the deferred tax assets will not be realized. A valuation allowance is provided for deferred income tax assets when, in our judgment, based upon currently available information and other factors, it is more likely than not that all or a portion of such deferred income tax assets will not be realized. The determination of the need for a valuation allowance is based on an on-going In determining when to release the valuation allowance established against our net deferred income tax assets, we consider all available evidence, both positive and negative. Consistent with our policy, the valuation allowance against our net deferred income tax assets will not be reversed until such time as we have generated three years of cumulative pre-tax pre-tax We account for uncertain tax positions utilizing a two-step more-likely-than-not more-likely-than-not Presently, we have not recorded a deferred tax liability for temporary differences related to investments in foreign subsidiaries that are essentially permanent in duration. These temporary differences may become taxable upon a repatriation of earnings from the subsidiaries or a sale or liquidation of the subsidiaries. At this time the Company does not have any plans to repatriate income from its foreign subsidiaries. New Accounting Standards Adoption of New Accounting Standards Accounting Standards Update (“ASU”) 2014-09, . ASU 2017-12 ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments.” ASU 2017-07, ASU 2017-01, ASU 2016-16, Intra-Entity Transfers of Assets Other than Inventory.” Accounting Standards Issued But Not Yet Adopted ASU 2017-04, ASU 2016-02, 2016-02, right-of-use 2016-02 2016-02 ASU 2018-02, 2018-02, 2018-02. ASU 2018-13, Fair Value Measurement.” Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement 2018-13 ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans.” Compensation - Retirement Benefits - Defined Benefit Plans - General Subtopic 715-20 2018-14

Acquisition

Acquisition	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Acquisition	NOTE 2 - ACQUISITION On May 30, 2017, the Company acquired 92.3 percent of the outstanding stock of Uniwheels (now referred to as our “Europe segment,” “Europe business”, “Europe operations” or “European operations”) for approximately $703.0 million (based on an exchange rate of 1.00 U.S. dollar = 3.74193 Polish Zloty) via a tender offer. On June 30, 2017, the Company commenced the delisting and associated tender process for the remaining outstanding shares of Uniwheels. As of December 31, 2018, a total of 12,213,079 shares have been tendered and the Company now owns 98.5 percent of the outstanding shares of Uniwheels. Superior pursued a Domination and Profit and Loss Transfer Agreement (“DPLTA”) which became effective on January 17, 2018, with retroactive effect as of January 1, 2018. Under the DPLTA, the Company offered to purchase any further tendered shares for cash consideration of Euro 62.18, or approximately Polish Zloty 264 per share. This cash consideration may be subject to change based on appraisal proceedings that the minority shareholders of Uniwheels have initiated. Because the aggregate equity purchase price of the Acquisition (assuming an exchange rate of 1.00 U.S. dollar = 3.74193 Polish Zloty) was determined at the time of the initial tender offer, any increase in the resulting price must be reflected as a reduction of paid in capital (common stock). Upon Uniwheels’ shareholder approval each year beginning in 2019, The Company must pay an annual dividend of Euro 3.38 on any then outstanding shares as long as the DPLTA is in effect. For any shares tendered prior to approval of the dividend each year, the Company must pay interest at a statutory rate, currently 4.12 percent, at the time the shares are redeemed. As a result of the effectiveness of the DPLTA as of January 1, 2018, the carrying value of the non-controlling non-controlling non-controlling non-controlling non-controlling The Company’s consolidated financial statements include the results of our European operations subsequent to May 30, 2017 (see Note 6, “Business Segments” for the more information). The Company’s consolidated financial statements reflect the purchase accounting adjustments in accordance with ASC 805 “Business Combinations”, whereby the purchase price was allocated to the assets acquired and liabilities assumed based upon their fair values on the acquisition date. The following is the allocation of the purchase price: (Dollars in thousands) Estimated purchase price Cash consideration $ 703,000 Non-controlling 63,200 Preliminary purchase price allocation Cash and cash equivalents 12,296 Accounts receivable 60,580 Inventories 83,901 Prepaid expenses and other current assets 11,859 Total current assets 168,636 Property and equipment 259,784 Intangible assets 205,000 Goodwill 286,249 Other assets 32,987 Total assets acquired 952,656 Accounts payable 61,883 Other current liabilities 40,903 Total current liabilities 102,786 Other long-term liabilities 83,670 Total liabilities assumed 186,456 Net assets acquired $ 766,200 Acquired intangible assets were recorded at estimated fair value, as determined through the use of the income approach, specifically the relief from royalty and multi-period excess earnings methods. The major assumptions used in arriving at the estimated identifiable intangible asset values included estimates of future cash flows, discounted at an appropriate rate of return which is based on the weighted average cost of capital for both the Company and other market participants. The useful lives for intangible assets were determined based upon the remaining useful economic lives of the intangible assets that are expected to contribute directly or indirectly to our future cash flows. The estimated fair value of intangible assets and related useful lives as included in the purchase price allocation include: Estimated Estimated (Dollars in thousands) Brand name $ 9,000 4-6 Technology 15,000 4-6 Customer relationships 167,000 7-11 Trade names 14,000 Indefinite $ 205,000 Goodwill represents future economic benefits expected to be recognized from the Company’s expansion into the European wheel market, as well as expected future synergies and operating efficiencies. The purchase price allocation of goodwill, which was finalized in the second quarter of 2018, yielding an amount of $286.2 million, was allocated to the Europe segment. The following unaudited combined pro forma information is for informational purposes only. The pro forma information is not necessarily indicative of what the combined Company’s results actually would have been had the acquisition been completed as of the beginning of the periods as indicated. In addition, the unaudited pro forma information does not purport to project the future results of the combined Company. Twelve Months Ended December 31, December 31, Proforma Proforma (Dollars in thousands) Proforma combined sales $ 1,351,799 $ 1,246,248 Proforma net income $ 17,692 $ 38,809

Revenue

Revenue	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue	NOTE 3 - REVENUE In accordance with ASC 606, the Company disaggregates revenue from contracts with customers into our segments, North America and Europe. Revenues by segment for the year ended December 31, 2018 are summarized in Note 6, “Business Segments”. The opening and closing balances of the Company’s receivables and current and long-term contract liabilities are as follows (in thousands): December 31, January 1, Change Customer receivables $ 97,566 $ 150,151 $ (52,585 ) Contract liabilities — current 5,810 5,736 74 Contract liabilities — noncurrent 8,354 5,222 3,132 The changes in the contract liability balances primarily result from timing differences between our performance and customer payment while the decline in customer receivables is primarily due to the sale of receivables (refer to Note 23, “Receivables Factoring”). During the year ended December 31, 2018, the Company recognized tooling reimbursement revenue of $8.5 million, which had been deferred in prior periods and was previously included in the current portion of the contract liability (deferred revenue). During the year ended December 31, 2018, the Company recognized revenue of $2.8 million from obligations satisfied in prior periods as a result of retrospective price adjustments arising from changes in commodity prices, production efficiencies and wheel weight variations.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE 4 - FAIR VALUE MEASUREMENTS The Company applies fair value accounting for all financial assets and liabilities and non-financial Level 1 - Quoted prices in active markets for identical assets or liabilities. Level 2 - Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 - Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability. The carrying amounts for cash and cash equivalents, investments in certificates of deposit, accounts receivable, accounts payable and accrued expenses approximate their fair values due to the short period of time until maturity. Cash and Cash Equivalents Cash and cash equivalents generally consist of cash, certificates of deposit and fixed deposits and money market funds with original maturities of three months or less. Certificates of deposit and fixed deposits whose original maturity is greater than three months and is one year or less are classified as short-term investments. Derivative Financial Instruments Our derivatives are over-the-counter non-performance Cash Surrender Value We have an unfunded salary continuation plan, which was closed to new participants effective February 3, 2011. We purchased life insurance policies on certain participants to provide, in part, for future liabilities. Refer to Note 18, “Retirement Plans.” The amount of the asset recorded for the investment in the life insurance contracts is equal to the cash surrender value which is the amount that will be realized under the contract as of the balance sheet date if the insured event occurs. The following tables categorize items measured at fair value at December 31, 2018 and 2017: Fair Value Measurement at Reporting Date Using December 31, 2018 Quoted Prices in Significant Other Significant (Dollars in thousands) Assets Certificates of deposit $ 750 $ — $ 750 $ — Cash surrender value 8,057 — 8,057 — Derivative contracts 4,218 — 4,218 — Total 13,025 — 13,025 — Liabilities Derivative contracts 8,836 — 8,836 Embedded derivative liability 3,134 — — 3,134 Total $ 11,970 $ — $ 8,836 $ 3,134 Fair Value Measurement at Reporting Date Using December 31, 2017 Quoted Prices in Significant Other Significant (Dollars in thousands) Assets Certificates of deposit $ 750 — $ 750 — Cash surrender value 8,040 — 8,040 — Derivative contracts 6,342 — 6,342 — Total 15,132 — 15,132 — Liabilities Derivative contracts 16,106 — 16,106 — Embedded derivative liability 4,685 — — 4,685 Total $ 20,791 — $ 16,106 $ 4,685 The following table summarizes the changes during 2018 and 2017 in level 3 fair value measurement of the embedded derivative liability relating to the redeemable preferred stock issued May 22, 2017 in connection with the acquisition of our European operations: January 1, 2017 – December 31, 2018 (Dollars in thousands) Beginning fair value – January 1, 2017 $ — Change in fair value of redeemable preferred stock embedded derivative liability 4,685 Ending fair value – December 31, 2017 4,685 Change in fair value of redeemable preferred stock embedded derivative liability (3,480 ) Effect of redeemable preferred stock modification 1,929 Ending fair value – December 31, 2018 3,134 Debt Instruments The carrying values of the Company’s debt instruments vary from their fair values. The fair values were determined by reference to transacted prices of these securities (Level 2 input based on the GAAP fair value hierarchy). The estimated fair value, as well as the carrying value, of the Company’s debt instruments are shown below (in thousands): December 31, December 31, (Dollars in thousands) Estimated aggregate fair value $ 624,943 $ 704,005 Aggregate carrying value (1) 684,922 707,864 (1) Long-term debt excluding the impact of unamortized debt issuance costs.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	NOTE 5 - DERIVATIVE FINANCIAL INSTRUMENTS Derivative Instruments and Hedging Activities We use derivatives to partially offset our exposure to foreign currency, interest rates, aluminum and other commodity risk. We may enter into forward contracts, option contracts, swaps, collars or other derivative instruments to offset some of the risk on expected future cash flows and on certain existing assets and liabilities. However, we may choose not to hedge certain exposures for a variety of reasons including, but not limited to, accounting considerations and the prohibitive economic cost of hedging particular exposures. There can be no assurance the hedges will offset more than a portion of the financial impact resulting from movements in foreign currency exchange rates, interest rates, and aluminum as well as natural gas commodity prices. To help protect gross margins from fluctuations in foreign currency exchange rates, certain of our subsidiaries, whose functional currency is the U.S. dollar or the Euro, hedge a portion of their forecasted foreign currency costs denominated in the Mexican Peso and Polish Zloty, respectively. We may hedge portions of our forecasted foreign currency exposure up to 48 months. We record all derivatives in the consolidated balance sheets at fair value. Our accounting treatment for these instruments is based on the hedge designation. The cash flow hedges that are designated as hedging instruments are recorded in Accumulated Other Comprehensive Income (“AOCI”) until the hedged item is recognized in earnings, at which point accumulated gains or losses will be recognized in earnings and classified with the underlying hedged transaction. Derivatives that are not designated as hedging instruments are adjusted to fair value through earnings in the financial statement line item to which the derivative relates. The Company has derivatives that are designated as hedging instruments as well as derivatives that did not qualify for designation as hedging instruments. Redeemable Preferred Stock Embedded Derivative We have determined that the conversion option embedded in our redeemable preferred stock is required to be accounted for separately from the redeemable preferred stock as a derivative liability. Separation of the conversion option as a derivative liability is required because its economic characteristics are considered more akin to an equity instrument and therefore the conversion option is not considered to be clearly and closely related to the economic characteristics of the redeemable preferred stock. This is because the economic characteristics of the redeemable preferred stock are considered more akin to a debt instrument due to the fact that the shares are redeemable at the holder’s option, the redemption value is significantly greater than the face amount, the shares carry a fixed mandatory dividend and the stock price necessary to make conversion more attractive than redemption ($56.324) is significantly greater than the price at the date of issuance ($19.05), all of which lead to the conclusion that redemption is more likely than conversion. We also have determined that the embedded early redemption option upon the occurrence of a redemption event (e.g. change of control, etc.) must also be bifurcated and accounted for separately from the redeemable preferred stock, because the debt host contract involves a substantial discount (face of $150.0 million as compared to the redemption value of $300.0 million) and exercise of the early redemption option would accelerate the holder’s option to redeem the shares. Accordingly, we have recorded an embedded derivative liability representing the combined fair value of the right of holders to receive common stock upon conversion of redeemable preferred stock at any time (the “conversion option”) and the right of the holders to exercise their early redemption option upon the occurrence of a redemption event (the “early redemption option”). The embedded derivative liability is adjusted to reflect fair value at each period end with changes in fair value recorded in the “Change in fair value of redeemable preferred stock embedded derivative” financial statement line item of the Company’s consolidated income statements (see Note 12, “Redeemable Preferred Stock.”) A binomial option pricing model is used to estimate the fair value of the conversion and early redemption options embedded in the redeemable preferred stock. The binomial model utilizes a “decision tree” whereby future movement in the Company’s common stock price is estimated based on a volatility factor. The binomial option pricing model requires the development and use of assumptions. These assumptions include estimated volatility of the value of our common stock, assumed possible conversion or early redemption dates, an appropriate risk-free interest rate, risky bond rate and dividend yield. The expected volatility of the Company’s common stock is estimated based on historical volatility. The assumed base case term used in the valuation model is the period remaining until September 14, 2025 (the earliest date at which the holder may exercise its unconditional redemption option). A number of other scenarios incorporate earlier redemption dates to address the possibility of early redemption upon the occurrence of a redemption event. The risk-free interest rate is based on the yield on the U.S. Treasury zero coupon yield curve with a remaining term equal to the expected term of the conversion and early redemption options. The significant assumptions utilized in the Company’s valuation of the embedded derivative at December 31, 2018 are as follows: valuation scenario terms between 3.00 and 6.70 years, volatility of 58 percent, risk-free rate of 2.5 percent to 2.6 percent related to the respective assumed terms, a risky bond rate of 22 percent and a dividend yield of 7.5 percent. The following tables display the fair value of derivatives by balance sheet line item at December 31, 2018 and December 31, 2017: December 31, 2018 Other Other Non-current Accrued Other Non-current (Dollars in thousands) Foreign exchange forward contracts designated as hedging instruments $ 2,599 1,011 659 6,202 Foreign exchange forward contracts not designated as hedging instruments 333 — 207 — Aluminum forward contracts designated as hedging instruments — — 927 — Cross currency swap not designated as hedging instrument — — 227 — Natural gas forward contracts designated as hedging instruments 275 — 355 — Interest rate swap contracts designated as hedging instruments — — 131 128 Embedded derivative liability — — — 3,134 Total derivative financial instruments $ 3,207 1,011 2,506 9,464 December 31, 2017 Other Other Non-current Accrued Other Non-current (Dollars in thousands) Foreign exchange forward contracts and collars designated as hedging instruments $ 3,065 723 4,922 8,405 Foreign exchange forward contracts not designated as hedging 721 — 206 — Aluminum forward contracts not designated as hedging instruments 1,833 — — — Cross currency swap not designated as hedging instrument — — 1,467 1,106 Embedded derivative liability — — — 4,685 Total derivative financial instruments $ 5,619 723 6,595 14,196 The following table summarizes the notional amount and estimated fair value of our derivative financial instruments: December 31, 2018 December 31, 2017 Notional Fair Notional Fair (Dollars in thousands) Foreign currency forward contracts and collars designated as hedging instruments $ 467,253 $ (3,251 ) $ 397,744 $ (9,539 ) Foreign exchange forward contracts not designated as hedging instruments 45,905 126 23,305 515 Aluminum forward contracts not designated as hedges 10,810 (927 ) 15,564 1,833 Cross currency swap not designated as hedging instrument 12,151 (227 ) 36,454 (2,573 ) Natural gas forward contracts designated as hedging instrument 2,165 (80 ) — — Interest rate swap contracts designated as hedging instrument 90,000 (259 ) — — Total derivative financial instruments $ 628,284 $ (4,618 ) $ 473,067 $ (9,764 ) Notional amounts are presented on a gross basis. The notional amounts of the derivative financial instruments do not represent amounts exchanged by the parties and, therefore, are not a direct measure of our exposure to the financial risks described above. The amounts exchanged are calculated by reference to the notional amounts and by other terms of the derivatives, such as interest rates, foreign currency exchange rates or commodity volumes and prices. The following tables summarize the gain or loss recognized in accumulated other comprehensive income (loss) (“AOCI”) as of December 31, 2018, 2017 and 2016 the amounts reclassified from AOCI into earnings and the amounts recognized directly into earnings for the years ended December 31, 2018, 2017 and 2016: Year ended December 31, 2018 Amount of Gain or (Loss) Amount of Pre-tax Gain or Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ 5,293 $ 728 $ (406 ) Total $ 5,293 $ 728 $ (406 ) Year ended December 31, 2017 Amount of Gain or (Loss) Amount of Pre-tax Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ 7,603 $ (4,539 ) $ (538 ) Total $ 7,603 $ (4,539 ) $ (538 ) Year ended December 31, 2016 Amount of Gain or (Loss) Amount of Pre-tax Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ (6,812 ) $ (13,597 ) $ (156 ) Total $ (6,812 ) $ (13,597 ) $ (156 )

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Business Segments	NOTE 6 - BUSINESS SEGMENTS As a result of our 2017 acquisition of Uniwheels, the Company expanded into the European market and extended its customer base to include the principal European OEMs. As a consequence, we have realigned our executive management structure, organization and operations to focus on our performance in the North American and European regions. In accordance with the requirements of ASC Topic 280, “Segment Reporting,” we have concluded that our North American and European businesses represent separate operating segments in view of significantly different markets, customers and products within each of these regions. Each operating segment has discrete financial information which is evaluated regularly by the Company’s CEO in determining resource allocation and assessing performance. Within each of these regions, markets, customers, products and production processes are similar and production can be readily transferred between production facilities. Moreover, our business within each region leverages common systems, processes and infrastructure. Accordingly, North America and Europe comprise the Company’s reportable segments for purposes of segment reporting. (Dollars in thousands) Net Sales Income from Operations 2018 2017 2016 2018 2017 2016 North America $ 800,383 $ 732,418 $ 732,677 $ 29,702 $ 9,808 $ 54,602 Europe 701,444 375,637 — 56,103 11,710 — $ 1,501,827 $ 1,108,055 $ 732,677 $ 85,805 $ 21,518 $ 54,602 (Dollars in thousands) Depreciation and Capital Expenditures 2018 2017 2016 2018 2017 2016 North America $ 33,588 $ 35,931 $ 34,261 $ 37,476 $ 47,493 $ 39,575 Europe 61,468 33,404 — 40,221 23,444 — $ 95,056 $ 69,335 $ 34,261 $ 77,697 $ 70,937 $ 39,575 (Dollars in thousands) Property, Plant, and Goodwill and 2018 2017 2018 2017 North America $ 249,791 $ 245,178 $ — $ — Europe 282,976 291,508 459,803 508,278 $ 532,767 $ 536,686 $ 459,803 $ 508,278 (Dollars in thousands) Total Assets 2018 2017 North America $ 484,682 $ 519,192 Europe 966,934 1,032,060 $ 1,451,616 $ 1,551,252 Geographic information Net sales by geographic location: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Net sales: U.S. $ 127,178 $ 124,711 $ 120,395 Mexico 673,205 607,707 612,282 Germany 279,631 155,227 — Poland 421,813 220,410 — Consolidated net sales $ 1,501,827 $ 1,108,055 $ 732,677

Accounts Receivable

Accounts Receivable	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Accounts Receivable	NOTE 7 - ACCOUNTS RECEIVABLE December 31, 2018 2017 (Dollars in thousands) Trade receivables $ 101,864 $ 152,476 Other receivables 7,083 10,016 108,947 162,492 Allowance for doubtful accounts (4,298 ) (2,325 ) Accounts receivable, net $ 104,649 $ 160,167 2018 2017 2016 Ford 18 % 22 % 38 % GM 18 % 20 % 30 % VW Group 12 % 9 % <1 % Toyota 8 % 9 % 14 % The accounts receivable from GM, Ford, VW Group and Toyota at December 31, 2018 represented approximately 24 percent, 11 percent, 8 percent and 6 percent of the total accounts receivable, respectively. The accounts receivable from GM, Ford and Toyota represented approximately 26 percent, 20 percent and 4 percent at December 31, 2017.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventories	NOTE 8 - INVENTORIES December 31, 2018 2017 (Dollars in thousands) Raw materials $ 49,571 $ 59,353 Work in process 42,886 48,803 Finished goods 83,121 65,843 Inventories, net $ 175,578 $ 173,999 Service wheel and supplies inventory included in other non-current

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	NOTE 9 - PROPERTY, PLANT AND EQUIPMENT December 31, 2018 2017 (Dollars in thousands) Land and buildings $ 140,471 $ 136,918 Machinery and equipment 769,451 720,175 Leasehold improvements and others 12,883 12,192 Construction in progress 67,559 58,753 990,364 928,038 Accumulated depreciation (457,597 ) (391,352 ) Property, plant and equipment, net $ 532,767 $ 536,686 Depreciation expense was $68.8 million, $54.2 million and $34.3 million for the years ended December 31, 2018, 2017 and 2016, respectively.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	NOTE 10 - GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill and indefinite-lived assets, such as certain trade names acquired in connection with the acquisition of our European operations on May 30, 2017, are not amortized, but are instead evaluated for impairment on an annual basis at the end of the fiscal year, or more frequently if events or circumstances indicate that impairment may be more likely than not. We conducted the annual goodwill impairment testing as of December 31, 2018. The Company evaluated its goodwill using a quantitative approach. The identification of potential impairment involves comparing the Company’s Europe reporting unit’s estimated fair value to its carrying value, including goodwill. In performing our valuation, we utilized an income approach and a market approach to determine fair value. The income approach is based on projected debt-free cash flow, which is discounted to the present value using discount factors that consider the timing and risk of cash flows. The discount rate used is the weighted average of an estimated cost of equity and of debt (“weighted average cost of capital”). The weighted average cost of capital is adjusted as necessary to reflect risk associated with the business of the Europe reporting unit. Business forecasts are based on estimated production volumes, product prices and expenses, including raw material cost, wages, energy and other expenses. Other significant assumptions include terminal value cash flow and growth rates, future capital expenditures and changes in future working capital requirements. The market approach is based on the observed ratios of enterprise value to earnings before interest, taxes, depreciation and amortization (EBITDA) of comparable, publicly traded companies. The market approach fair value is determined by multiplying historical and anticipated financial metrics of the Europe reporting unit by the EBITDA pricing multiples derived from the comparable, publicly traded companies. Our assessment indicated that the fair value of the European reporting unit exceeded its respective carrying value. The Company’s finite lived intangible assets are amortized on a straight-line basis over their estimated useful lives. Following is a summary of the Company’s finite-lived and indefinite-lived intangible assets and goodwill as of December 31, 2018 and 2017. Gross Accumulated Currency Net Remaining Year Ended December 31, 2018 (Dollars in thousands) Brand name $ 9,000 $ (2,979 ) $ 237 $ 6,258 4-5 Technology 15,000 (4,964 ) 394 10,430 3-5 Customer relationships 167,000 (33,468 ) 3,823 137,355 5-10 Total finite 191,000 (41,411 ) 4,454 154,043 Trade names 14,000 — 326 14,326 Indefinite Total intangibles $ 205,000 $ (41,411 ) $ 4,780 $ 168,369 Beginning Currency Ending Year Ended December 31, 2018 (Dollars in thousands) Goodwill $ 304,805 $ (13,371 ) $ 291,434 Gross Accumulated Currency Net Remaining Year Ended December 31, 2017 (Dollars in thousands) Brand name $ 9,000 $ (1,091 ) $ 581 $ 8,490 5-6 Technology 15,000 (1,818 ) 968 14,150 4-6 Customer relationships 167,000 (12,259 ) 11,005 165,746 6-11 Total finite 191,000 (15,168 ) 12,554 188,386 Trade names 14,000 — 1,087 15,087 Indefinite Total intangibles $ 205,000 $ (15,168 ) $ 13,641 $ 203,473 Beginning Currency Ending Year Ended December 31, 2017 (Dollars in thousands) Goodwill $ 286,249 $ 18,556 $ 304,805 Amortization expense for these intangible assets was $26.3 million and $15.2 million for the years ended December 31, 2018 and 2017, respectively. The anticipated annual amortization expense for these intangible assets is $25.0 million for 2019 to 2021, $22.2 million for 2022 and $20.2 million for 2023.

Debt

Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	NOTE 11 - DEBT A summary of long-term debt and the related weighted average interest rates is shown below: December 31, 2018 Debt Instrument Total Debt (1) Total Weighted Term Loan Facility $ 382,800 $ (13,078 ) $ 369,722 6.3 % 6.00% Senior Notes due 2025 286,100 (7,366 ) 278,734 6.0 % Other 16,022 — 16,022 2.2 % $ 684,922 $ (20,444 ) 664,478 Less: Current portion (3,052 ) Long-term debt $ 661,426 December 31, 2017 Debt Instrument Total Debt (1) Total Weighted Term Loan Facility $ 386,800 $ (15,802 ) $ 370,998 5.6 % 6.00% Senior Notes due 2025 300,250 (8,510 ) 291,740 6.0 % Other 20,814 — 20,814 1.0 % $ 707,864 $ (24,312 ) 683,552 Less: Current portion (4,000 ) Long-term debt $ 679,552 (1) Unamortized portion Senior Notes On June 15, 2017, Superior issued Euro 250.0 million aggregate principal amount of 6.00% Senior Notes (the “Notes”) due June 15, 2025. Interest on the Notes is payable semiannually, on June 15 and December 15. Superior may redeem the Notes, in whole or in part, on or after June 15, 2020 at redemption prices of 103.000% and 101.500% of the principal amount thereof if the redemption occurs during the 12-month Guarantee The Notes are unconditionally guaranteed by all material wholly-owned direct and indirect domestic restricted subsidiaries of the Company (the “Subsidiary Guarantors”), with customary exceptions including, among other things, where providing such guarantees is not permitted by law, regulation or contract or would result in adverse tax consequences. Covenants Subject to certain exceptions, the indenture governing the Notes contains restrictive covenants that, among other things, limit the ability of Superior and the Subsidiary Guarantors to: (i) incur additional indebtedness or issue certain preferred stock; (ii) pay dividends on, or make distributions in respect of, their capital stock; (iii) make certain investments or other restricted payments; (iv) sell certain assets or issue capital stock of restricted subsidiaries; (v) create liens; (vi) merge, consolidate, transfer or dispose of substantially all of their assets; and (vii) engage in certain transactions with affiliates. These covenants are subject to several important limitations and exceptions that are described in the indenture. The indenture provides for customary events of default that include, among other things (subject in certain cases to customary grace and cure periods): (i) nonpayment of principal, premium, if any, and interest, when due; (ii) breach of covenants in the indenture; (iii) a failure to pay certain judgments; and (iv) certain events of bankruptcy and insolvency. If an event of default occurs and is continuing, the Bank of New York Mellon, London Branch (“the Trustee”) or holders of at least 30% in principal amount of the then outstanding Notes may declare the principal, premium, if any, and accrued and unpaid interest on all the Notes to be due and payable. These events of default are subject to several important qualifications, limitations and exceptions that are described in the indenture. As of December 31, 2018, the Company was in compliance with all covenants under the indenture governing the Notes. Senior Secured Credit Facilities On March 22, 2017, Superior entered into a senior secured credit agreement (the “Credit Agreement”) with Citibank, N.A, as Administrative Agent, Collateral Agent and Issuing Bank, JP Morgan Chase N.A., Royal Bank of Canada and Deutsche Bank A.G. New York Branch as Joint Lead Arrangers and Joint Book Runners, and the other lenders party thereto (collectively, the “Lenders”). The Credit Agreement consisted of a $400.0 million senior secured term loan facility (the “Term Loan Facility”), which matures on May 22, 2022, and a $160.0 million revolving credit facility maturing on May 23, 2024 (the “Revolving Credit Facility” and, together with the Term Loan Facility, the “Senior Secured Credit Facilities”). On June 29, 2018, the Company entered into an amendment to the Credit Agreement pursuant to which the interest rate under the Term Loan Facility was reduced to LIBOR plus 4.00 percent (from LIBOR plus 4.50 percent), subject to a LIBOR floor of 0.00 percent (in place of the previous LIBOR floor of 1.00 percent). Substantially all of the original loans under the Term Loan Facility were replaced with loans from existing lenders under terms that were not substantially different than those of the original loans. As a result, this transaction did not result in any debt extinguishment and the unamortized debt issuance costs associated with the original loans will continue to be amortized over the remaining term of the replacement loans (which is unchanged from the original term). Borrowings under the Term Loan Facility will bear interest at a rate equal to, at the Company’s option, either (a) LIBOR for the relevant interest period, adjusted for statutory reserve requirements, subject to a floor of 0.00 percent per annum, plus an applicable rate of 4.00 percent or (b) a base rate, subject to a floor of 2.00 percent per annum, equal to the highest of (1) the rate of interest in effect as publicly announced by the administrative agent as its prime rate, (2) the federal funds rate plus 0.50 percent and (3) LIBOR for an interest period of one month plus 1.00 percent, in each case, plus an applicable rate of 3.50 percent. Borrowings under the Revolving Credit Facility initially bear interest at a rate equal to, at the Company’s option, either (a) LIBOR for the relevant interest period, adjusted for statutory reserve requirements, subject to a floor of 1.00 percent per annum, plus an applicable rate of 3.50 percent or (b) a base rate, equal to the highest of (1) the rate of interest in effect as publicly announced by the administrative agent as its prime rate, (2) the federal funds effective rate plus 0.50 percent and (3) LIBOR for an interest period of one month plus 1.00 percent, in each case, plus an applicable rate of 2.50 percent provided such rate may not be less than zero. The initial commitment fee for unused commitments under the Revolving Credit Facility shall be 0.50 percent. The applicable rates for borrowings under the Revolving Credit Facility and commitment fees for unused commitments under the Revolving Credit Facility are based upon the First Lien Net Leverage Ratio effective for the preceding quarter with LIBOR applicable rates between 3.50 percent and 3.00 percent, base rate applicable rates between 2.50 percent and 2.00 percent and commitment fees between 0.50 percent and 0.25 percent. Commitment fees are included in our consolidated financial statements line, interest (expense) income, net. As of December 31, 2018, the Company had repaid $17.2 million under the Term Loan Facility resulting in a balance of $382.8 million. As of December 31, 2018, the Company had no outstanding borrowings under the Revolving Credit Facility, had outstanding letters of credit of $3.4 million and available unused commitments under this facility of $156.6 million. Guarantees and Collateral Security Our obligations under the Credit Agreement are unconditionally guaranteed by all material wholly-owned direct and indirect domestic restricted subsidiaries of the Company, with customary exceptions including, among other things, where providing such guarantees is not permitted by law, regulation or contract or would result in adverse tax consequences. The guarantees of such obligations, will be secured, subject to permitted liens and other exceptions, by substantially all of our assets and the Subsidiary Guarantors’ assets, including but not limited to: (i) a perfected pledge of all of the capital stock issued by each of the Company’s direct wholly-owned domestic restricted subsidiaries or any guarantor (subject to certain exceptions) and up to 65 percent of the capital stock issued by each direct wholly-owned foreign restricted subsidiary of the Company or any guarantor (subject to certain exceptions) and (ii) perfected security interests in and mortgages on substantially all tangible and intangible personal property and material fee-owned Covenants The Senior Secured Credit Facilities contain a number of restrictive covenants that, among other things, restrict, subject to certain exceptions, our ability to incur additional indebtedness and guarantee indebtedness, create or incur liens, engage in mergers or consolidations, sell, transfer or otherwise dispose of assets, make investments, acquisitions, loans or advances, pay dividends, distributions or other restricted payments, or repurchase our capital stock, prepay, redeem, or repurchase any subordinated indebtedness, enter into agreements which limit our ability to incur liens on our assets or that restrict the ability of restricted subsidiaries to pay dividends or make other restricted payments to us, and enter into certain transactions with our affiliates. In addition, the Credit Agreement contains customary default provisions, representations and warranties and other covenants. The Credit Agreement also contains a provision permitting the Lenders to accelerate the repayment of all loans outstanding under the Senior Secured Credit Facilities during an event of default. As of December 31, 2018, the Company was in compliance with all covenants under the Credit Agreement. Acquisition Debt In connection with the acquisition of Unwheels, the Company assumed $70.7 million of outstanding debt. At December 31, 2018, $16.0 million of debt remained outstanding relating to an equipment loan of which $3.1 million was classified as current. The Company also has an available unused line of credit of Euro 30.0 million which expires July 31, 2020. The line of credit bears interest at Euribor plus 1.0 percent (but in any event not less than 0.95 percent) and the equipment loan bears interest at 2.2 percent.

Redeemable Preferred Stock

Redeemable Preferred Stock	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Redeemable Preferred Stock	NOTE 12 - REDEEMABLE PREFERRED STOCK During 2017, we issued 150,000 shares of Series A (140,202 shares) and Series B (9,798 shares) Perpetual Convertible Preferred Stock, par value $0.01 per share to TPG Growth III Sidewall, L.P. (TPG) for an aggregate purchase price of $150.0 million. On August 30, 2017, the Series B shares were converted into Series A redeemable preferred stock, the “redeemable preferred stock” after approval by our shareholders. The redeemable preferred stock has an initial stated value of $1,000 per share, par value of $0.01 per share and liquidation preference over common stock. The redeemable preferred stock is convertible into shares of our common stock equal to the number of shares determined by dividing the sum of the stated value and any accrued and unpaid dividends by the conversion price of $28.162. The redeemable preferred stock accrues dividends at a rate of 9 percent per annum, payable at our election either in-kind We may mandate conversion of the redeemable preferred stock if the price of the common stock exceeds $84.49. TPG may redeem the shares upon the occurrence of any of the following events (referred to as a “redemption event”): a change in control, recapitalization, merger, sale of substantially all of the Company’s assets, liquidation or delisting of the Company’s common stock. In addition, as originally issued, TPG had the right, at its option, to unconditionally redeem the shares at any time after May 23, 2024, (the “redemption date”). We may, at our option, redeem in whole at any time all of the shares of redeemable preferred stock outstanding. At redemption by either party, the redemption value will be the greater of $300.0 million (2.0 times stated value) or the product of the number of common shares into which the redeemable preferred stock could be converted (5.3 million shares currently) and the then current market price of the common stock. We have determined that the conversion option and the redemption option exercisable upon occurrence of a “redemption event” which are embedded in the redeemable preferred stock must be accounted for separately from the redeemable preferred stock as a derivative liability. We have also determined that the early redemption option exercisable on the occurrence of a redemption event must also be bifurcated and accounted for separately as a derivative liability (as more fully described under Note 5, “Derivative Financial Instruments”). Since the redeemable preferred stock may be redeemed at the option of the holder, but is not mandatorily redeemable, the redeemable preferred stock has been classified as mezzanine equity and initially recognized at fair value of $150.0 million (the proceeds on the date of issuance) less issuance costs of $3.7 million, resulting in an initial value of $146.3 million. This amount has been further reduced by $10.9 million assigned to the embedded derivative liability at date of issuance, resulting in an adjusted initial value of $135.5 million. The difference between the adjusted initial value of $135.5 million and the redemption value of $300 million was being accreted over the eight-year period from the date of issuance through September 14, 2025 (the original date at which the holder had the unconditional right to redeem the shares, deemed to be the earliest likely redemption date) using the effective interest method. The accretion to the carrying value of the redeemable preferred stock is treated as a deemed dividend, recorded as a charge to retained earnings and deducted in computing earnings per share (analogous to the treatment for stated and participating dividends paid on the redeemable preferred shares). On November 7, 2018, the Company filed a Certificate of Correction to the Certificate of Designations for the preferred stock, which became effective upon filing and corrected the redemption date to September 14, 2025. This resulted in a modification of the redeemable preferred stock. As a result of the modification, the carrying value of the redeemable preferred stock decreased $17.2 million (which was credited to retained earnings, treated as a deemed dividend and is added back to compute earnings per share) and the period for accretion of the carrying value to the redemption value has been extended to September 14, 2025. The accretion has been adjusted to amortize the excess of the redemption value over the carrying value over the period through September 14, 2025. The accumulated accretion net of the modification adjustment as of December 31, 2018 is $9.0 million resulting in an adjusted redeemable preferred stock balance of $144.5 million.

European Non-Controlling Redeem

European Non-Controlling Redeemable Equity	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest [Abstract]
European Non-Controlling Redeemable Equity	NOTE 13 - EUROPEAN NON-CONTROLLING On January 17, 2018, the DPLTA (referred to in Note 2, “Acquisition”) became effective retroactively to January 1, 2018. As a result, non-controlling non-controlling non-controlling non-controlling Balance at December 31, 2017 $ — Reclassification of non-controlling 51,943 Redemption value adjustment 3,625 Dividends accrued 1,512 Dividends paid (964 ) Translation adjustment (3,219 ) Purchase of shares (39,048 ) Balance at December 31, 2018 $ 13,849 Annual compensation payable on untendered outstanding shares under the DPLTA must be recognized as it accrues, whether declared or paid. As of December 31, 2018, we have recognized $1.5 million representing the annual dividend to the European non-controlling

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	NOTE 14 - EARNINGS PER SHARE Basic earnings per share is computed by dividing net income (loss) attributable to Superior, after adjusting for preferred dividend, European non-controlling Year Ended December 31, 2018 2017 2016 (Dollars in thousands, except per share amounts) Basic Earnings Per Share: Reported net income (loss) attributable to Superior $ 25,961 $ (6,203 ) $ 41,381 Less: Redeemable preferred stock dividends and accretion (32,462 ) (18,912 ) — Add: Preferred stock modification 15,257 — — Less: European non-controlling (1,512 ) — — Basic numerator $ 7,244 $ (25,115 ) $ 41,381 Basic earnings (loss) per share $ 0.29 $ (1.01 ) $ 1.63 Weighted average shares outstanding-Basic 24,994 24,929 25,439 Diluted Earnings Per Share: Reported net income (loss) attributable to Superior $ 25,961 $ (6,203 ) $ 41,381 Less: Redeemable preferred stock dividends and accretion (32,462 ) (18,912 ) — Add: Preferred stock modification 15,257 — — Less: European non-controlling (1,512 ) — — Diluted numerator $ 7,244 $ (25,115 ) $ 41,381 Diluted earnings (loss) per share $ 0.29 $ (1.01 ) $ 1.62 Weighted average shares outstanding-Basic 24,994 24,929 25,439 Dilutive effect of common share equivalents 161 — 100 Weighted average shares outstanding-Diluted 25,155 24,929 25,539

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	NOTE 15 - INCOME TAXES Income before income taxes from domestic and international jurisdictions is comprised of the following: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Income before income taxes: Domestic $ (44,058 ) $ (63,716 ) $ 18,499 Foreign 76,310 64,582 36,222 $ 32,252 $ 866 $ 54,721 The provision for income taxes is comprised of the following: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Current taxes Federal $ 3,714 $ 6,121 $ (5,017 ) State 127 (390 ) 450 Foreign (11,180 ) (12,564 ) (10,639 ) Total current taxes (7,339 ) (6,833 ) (15,206 ) Deferred taxes Federal (919 ) (4,387 ) (1,199 ) State 521 1,492 (332 ) Foreign 1,446 2,853 3,397 Total deferred taxes 1,048 (42 ) 1,866 Income tax provision $ (6,291 ) $ (6,875 ) $ (13,340 ) The following is a reconciliation of the U.S. federal tax rate to our effective income tax rate: Year Ended December 31, 2018 2017 2016 Statutory rate (21.0 )% (35.0 )% (35.0 )% State tax provisions, net of federal income tax benefit 6.4 263.4 (6.3 ) Tax credits 1.3 88.9 0.6 Foreign income taxes at rates other than the statutory rate 16.8 1,206.6 11.7 Valuation allowance and other (28.0 ) (138.0 ) 5.1 Changes in tax liabilities, net (0.6 ) (11.3 ) 0.5 Share based compensation (1.0 ) (61.5 ) (1.2 ) Transaction costs — (372.2 ) — US Tax Reform implementation 10.9 (1,918.7 ) — US Tax on non-US (16.1 ) — — Non-taxable 16.3 152.6 — Other (4.5 ) 31.3 0.2 Effective income tax rate (19.5 )% (793.9 )% (24.4 )% Tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and deferred liabilities are as follows: December 31, 2018 2017 (Dollars in thousands) Deferred income tax assets: Accrued liabilities $ 8,117 $ 2,445 Hedging and foreign currency losses (1,163 ) 2,034 Deferred compensation 8,021 8,628 Inventory reserves 3,984 2,954 Net loss carryforwards and credits 51,552 69,018 Interest carryforwards 11,269 — Competent authority deferred tax assets and other foreign timing differences 6,749 6,939 Other (3,921 ) (830 ) Total before valuation allowance 84,608 91,188 Valuation allowance (16,576 ) (7,634 ) Net deferred income tax assets 68,032 83,554 Deferred income tax liabilities: Intangibles, property, plant and equipment and other (44,591 ) (57,791 ) Deferred income tax liabilities (44,591 ) (57,791 ) Net deferred income tax assets $ 23,441 $ 25,763 The classification of our net deferred tax asset is shown below: December 31, 2018 2017 (Dollars in thousands) Long-term deferred income tax assets $ 42,105 $ 54,302 Long-term deferred income tax liabilities (18,664 ) (28,539 ) Net deferred tax asset $ 23,441 $ 25,763 Realization of any of our deferred tax assets at December 31, 2018 is dependent on the Company generating sufficient taxable income in the future. The determination of whether or not to record a full or partial valuation allowance on our deferred tax assets is a critical accounting estimate requiring a significant amount of judgment on the part of management. In determining when to release the valuation allowance established against our deferred income tax assets, we consider all available evidence, both positive and negative. We perform our analysis on a jurisdiction by jurisdiction basis at the end of each reporting period. The increase in the valuation allowance of $9.0 million relates primarily to interest expense subject to limitations on deductibility in the U.S. The Tax Cut and Jobs Act (“the Act”) was enacted on December 22, 2017. The Act contains significant changes to corporate taxation, including the reduction of the corporate tax rate from 35 percent to 21 percent, a one-time Low-Tax The Company had recorded provisional amounts for enactment-date income tax effects of the Act at December 31, 2017 following the guidance in SAB 118. At December 31, 2018 the Company has completed the accounting for all enactment-date income tax effects of the Act and recorded a benefit of $3.9 million as an adjustment to the provisional amounts. The Company also recorded $5.2 million expense related to GILTI. As of December 31, 2018, we have cumulative tax effected U.S. federal, state and Germany NOL carryforwards of $12.9 million that expire in the years 2019 to 2038. Also, we have $38.6 million of tax credit carryforwards, primarily in Poland, which expire in the years 2021 to 2026. The transition tax substantially eliminated the basis difference that existed previously for purposes of ASC Topic 740. However, there are limited other taxes that could continue to apply such as foreign withholding and certain state taxes. Taxes have not been provided on basis differences in investments of $173 million that are deemed indefinitely reinvested. Quantification of the deferred tax liability, if any, associated with indefinitely reinvested basis differences is not practicable. We account for our uncertain tax positions in accordance with U.S. GAAP. A reconciliation of the beginning and ending amounts of these tax benefits is as follows: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Beginning balance $ 33,054 $ 3,446 $ 7,318 Increases (decreases) due to foreign currency translations (2,018 ) — — Increases (decreases) as a result of positions taken during: Prior periods — — (3,872 ) Current period — 29,773 — Expiration of applicable statutes of limitation — (165 ) — Ending balance $ 31,036 $ 33,054 $ 3,446 Our policy regarding interest and penalties related to uncertain tax positions is to record interest and penalties as an element of income tax expense. At the end of 2018, 2017 and 2016 the Company had liabilities of $3.3 million, $2.4 million and $1.8 million of potential interest and penalties associated with uncertain tax positions. Included in the unrecognized tax benefits is $2.2 million that, if recognized, would favorably affect our annual effective tax rate. Within the next twelve-month period we do not expect a decrease in unrecognized tax benefits. Income tax returns are filed in multiple jurisdictions and are subject to examination by tax authorities in various jurisdictions where the Company operates. The Company has open tax years from 2013 to 2018 with various significant tax jurisdictions.

Leases

Leases	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Leases	NOTE 16 - LEASES We lease certain land, facilities and equipment under long-term operating leases expiring at various dates through 2026. Total lease expense for all operating leases amounted to $7.0 million in 2018, $4.3 million in 2017 and $1.9 million in 2016. The following are summarized future minimum payments under our operating leases: Year Ended December 31, Operating (Dollars in thousands) 2019 $ 4,249 2020 3,232 2021 2,870 2022 2,635 2023 2,346 Thereafter 7,647 $ 22,979

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Parties	NOTE 17 - RELATED PARTIES Purchase Agreement In the first quarter of 2015, we entered into an agreement to purchase a subscription to online software provided by NGS Inc. Our former Senior Vice President, Business Operations and our Vice President of Information Technology are passive investors in NGS. We made payments to NGS of $479,520, $376,920 and $243,000 during the 2018, 2017 and 2016 fiscal years, respectively. The transaction was entered into in the ordinary course of business and is an arms-length transaction agreement.

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Retirement Plans	NOTE 18 - RETIREMENT PLANS We have an unfunded salary continuation plan covering certain directors, officers and other key members of management. We purchase life insurance policies on certain participants to provide in part for future liabilities. Cash surrender value of these policies, totaling $8.1 million and $8.0 at December 31, 2018 and 2017, respectively, are included in other non-current The following table summarizes the changes in plan assets and plan benefit obligations: Year Ended December 31, 2018 2017 (Dollars in thousands) Change in benefit obligation Beginning benefit obligation $ 29,759 $ 27,612 Interest cost 1,086 1,189 Actuarial (gain) loss (2,486 ) 2,300 Benefit payments (1,406 ) (1,342 ) Ending benefit obligation $ 26,953 $ 29,759 Year Ended December 31, 2018 2017 (Dollars in thousands) Change in plan assets Fair value of plan assets at beginning of year $ — $ — Employer contribution 1,406 1,342 Benefit payments (1,406 ) (1,342 ) Fair value of plan assets at end of year $ — $ — Funded status $ (26,953 ) $ (29,759 ) Amounts recognized in the consolidated balance sheets consist of: Accrued expenses (1,392 ) (1,407 ) Other non-current (25,561 ) (28,352 ) Net amount recognized $ (26,953 ) $ (29,759 ) Amounts recognized in accumulated other comprehensive loss consist of: Net actuarial loss $ 4,799 $ 7,722 Prior service cost (1 ) (1 ) Net amount recognized, before tax effect $ 4,798 $ 7,721 Weighted average assumptions used to determine benefit obligations: Discount rate 4.4 % 3.7 % Rate of compensation increase 3.0 % 3.0 % Components of net periodic pension cost are described in the following table: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Components of net periodic pension cost: Interest cost 1,086 1,189 1,216 Amortization of actuarial loss 438 369 335 Net periodic pension cost 1,524 1,558 $ 1,551 Weighted average assumptions used to determine net periodic pension cost: Discount rate 3.7 % 4.4 % 4.4 % Rate of compensation increase 3.0 % 3.0 % 3.0 % Benefit payments during the next ten years, which reflect applicable future service, are as follows: Year Ended December 31, Amount (Dollars in thousands) 2019 $ 1,422 2020 $ 1,484 2021 $ 1,457 2022 $ 1,495 2023 $ 1,472 Years 2024 to 2028 $ 8,448 The following is an estimate of the components of net periodic pension cost in 2019: Estimated Year Ended December 31, 2019 (Dollars in thousands) Interest cost 1,144 Amortization of actuarial loss 209 Estimated 2019 net periodic pension cost $ 1,353 Other Retirement Plans We also contribute to employee retirement savings plans in the U.S. and Mexico that cover substantially all of our employees in those countries. The employer contribution totaled $1.8 million, $1.7 million and $1.4 million for the three years ended December 31, 2018, 2017 and 2016, respectively.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Accrued Expenses	NOTE 19 - ACCRUED EXPENSES December 31, 2018 2017 (Dollars in thousands) Payroll and related benefits $ 23,503 $ 27,954 Insurance Reserves 1,120 590 Taxes, other than income taxes 8,115 9,419 Current portion of derivative liability 2,506 6,595 Dividends and interest 4,197 7,322 Deferred tooling revenue 5,810 4,654 Current portion of executive retirement liabilities 1,392 1,407 Professional Fees 4,750 3,674 Warranty Liability 437 872 Other 13,832 6,299 Accrued liabilities $ 65,662 $ 68,786

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	NOTE 20 - STOCK-BASED COMPENSATION Equity Incentive Plan Our 2018 Equity Incentive Plan (the “Plan”) was approved by stockholders in May 2018 and amended and restated the 2008 Equity Incentive Plan. The Plan authorizes us to issue up to 4.35 million shares of common stock, along with non-qualified non-employee Per the terms of the program, each year eligible participants are granted time value restricted stock units (“RSUs”), vesting ratably over a three-year time period, and performance restricted stock units (“PSUs”), with a three-year cliff vesting. Upon vesting, each restricted stock award is exchangeable for one share of the Company’s common stock, with accrued dividends. Stock-based compensation expense was $2.1 million, $1.6 million, and $2.3 million for the years ended December 31, 2018, 2017, 2016, respectively. Unrecognized stock-based compensation expense related to non-vested Equity Incentive Awards Restricted Weighted Performance Weighted Options Weighted Balance at December 31, 2017 169,266 $ 22.27 239,674 $ 22.58 145,625 $ 18.96 Granted 204,003 $ 15.91 325,526 $ 17.12 — — Settled (66,138 ) $ 22.67 — — (4,500 ) $ 15.17 Forfeited or expired (123,405 ) $ 18.98 (268,677 ) $ 19.8 (82,125 ) $ 19.62 Balance at December 31, 2018 183,726 $ 17.26 296,523 $ 19.1 59,000 $ 18.33 Vested or expected to vest at December 31, 2018 183,726 111,071 59,000

Common Stock Repurchase Program

Common Stock Repurchase Programs	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Common Stock Repurchase Programs	NOTE 21 - COMMON STOCK REPURCHASE PROGRAMS In January 2016, our Board of Directors approved a common stock repurchase program (the “Repurchase Program”), authorizing the repurchase of up to $50.0 million of our common stock. Under the Repurchase Program we have previously purchased $15.4 million leaving a remaining authorization of $34.6 million which we may repurchase from time to time on the open market or in private transactions. The timing and extent of the repurchases under the Repurchase Program will depend upon market conditions and other corporate considerations in our sole discretion. There were no repurchases under this program for the year ended December 31, 2018.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE 22 - COMMITMENTS AND CONTINGENCIES Purchase Commitments When market conditions warrant, we may enter into purchase commitments to secure the supply of certain commodities used in the manufacture of our products, such as aluminum, natural gas and other raw materials. Prices under our aluminum contracts are based on a market index, such as the London Mercantile Exchange (LME), and regional premiums for processing, transportation and alloy components which are adjusted quarterly for purchases in the ensuing quarter. Changes in aluminum prices are generally passed through to our OEM customers and adjusted on a quarterly basis. Certain of our purchase agreements include volume commitments, however any excess commitments are generally negotiated with suppliers and those which have occurred in the past have been carried over to future periods. Contingencies We are party to various legal and environmental proceedings incidental to our business. Certain claims, suits and complaints arising in the ordinary course of business have been filed or are pending against us. Based on facts now known, we believe all such matters are adequately provided for, covered by insurance, are without merit and/or involve such amounts that would not materially adversely affect our consolidated results of operations, cash flows or financial position.

Receivables Factoring

Receivables Factoring	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Receivables Factoring	NOTE 23 - RECEIVABLES FACTORING The Company sells certain customer trade receivables on a non-recourse

Quarterly Financial Data

Quarterly Financial Data	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	NOTE 24 - QUARTERLY FINANCIAL DATA (UNAUDITED) (Dollars in thousands, except per share amounts) Year 2018 First Second Third Fourth Year Net sales $ 386,448 $ 388,944 $ 347,612 $ 378,823 $ 1,501,827 Gross profit $ 49,991 $ 53,559 $ 23,673 $ 36,304 $ 163,527 Income from operations $ 27,634 $ 31,270 $ 7,688 $ 19,213 $ 85,805 Consolidated income (loss) before income taxes $ 13,687 $ 12,930 $ (7,714 ) $ 13,349 $ 32,252 Income tax (provision) benefit $ (3,370 ) $ (4,795 ) $ 7,051 $ (5,177 ) $ (6,291 ) Consolidated net income (loss) $ 10,317 $ 8,135 $ (663 ) $ 8,172 $ 25,961 Income (loss) per share (1) Basic (1) $ 0.07 $ (0.02 ) $ (0.37 ) $ 0.61 $ 0.29 Diluted (1) $ 0.07 $ (0.02 ) $ (0.37 ) $ 0.61 $ 0.29 Dividends declared per share $ 0.09 $ 0.09 $ 0.09 $ 0.09 $ 0.36 Statement of Comprehensive Income: Other comprehensive income (loss), net of tax (1) $ 34,901 $ (53,178 ) $ 21,960 $ (20,057 ) $ (16,374 ) (1) Subsequent to the issuance of the September 30, 2018 interim financial statements, the Company identified an error related to the classification of foreign currency translation adjustments associated with the European non-controlling non-controlling Year 2017 First Second Third Fourth Year Net sales $ 174,220 $ 240,628 $ 331,404 $ 361,803 $ 1,108,055 Gross profit $ 19,204 $ 20,105 $ 23,893 $ 39,695 $ 102,897 Income (loss) from operations $ 3,944 $ (1,998 ) $ 5,758 $ 13,814 $ 21,518 Consolidated income (loss) before income taxes $ 3,300 $ (9,241 ) $ (501 ) $ 7,308 $ 866 Income tax (provision) benefit $ (198 ) $ 1,722 $ 3,355 $ (11,754 ) $ (6,875 ) Consolidated net income (loss) $ 3,102 $ (7,519 ) $ 2,854 $ (4,446 ) $ (6,009 ) Less: Net loss (income) attributable to non-controlling — $ 247 $ (239 ) $ (202 ) $ (194 ) Net income (loss) attributable to Superior $ 3,102 $ (7,272 ) $ 2,615 $ (4,648 ) $ (6,203 ) Income (loss) per share: Basic $ 0.12 $ (0.41 ) $ (0.22 ) $ (0.50 ) $ (1.01 ) Diluted $ 0.12 $ (0.41 ) $ (0.22 ) $ (0.50 ) $ (1.01 ) Dividends declared per share $ 0.18 $ 0.09 $ 0.09 $ 0.09 $ 0.45

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	VALUATION AND QUALIFYING ACCOUNTS FOR THE YEARS ENDED DECEMBER 31, 2018, 2017 AND 2016 (Dollars in thousands) Additions Balance Charge Other Deductions Balance 2018 Allowance for doubtful accounts receivable $ 2,325 $ 2,311 $ — $ (338 ) $ 4,298 Valuation allowances for deferred tax assets $ 7,634 $ 9,036 $ — (94 ) $ 16,576 2017 Allowance for doubtful accounts receivable $ 919 $ 1,127 $ 1,162 $ (883 ) $ 2,325 Valuation allowances for deferred tax assets $ 3,123 $ 1,005 $ 3,506 — $ 7,634 2016 Allowance for doubtful accounts receivable $ 867 $ 403 $ — $ (351 ) $ 919 Valuation allowances for deferred tax assets $ 5,891 $ 698 $ — $ (3,466 ) $ 3,123

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Superior Industries International, Inc. (referred to herein as the “Company” or “we,” “us” and “our”) designs and manufactures aluminum wheels for sale to original equipment manufacturers (“OEMs”) and aftermarket customers. We are one of the largest suppliers of cast aluminum wheels to the world’s leading automobile and light truck manufacturers, with manufacturing operations in the United States, Mexico, Germany and Poland. Our OEM aluminum wheels are sold primarily for factory installation, as either standard equipment or optional equipment, on vehicle models manufactured by BMW-Mini, (Mercedes-Benz,
Presentation of Consolidated Financial Statements	Presentation of Consolidated Financial Statements The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions are eliminated in consolidation. Accounting estimates are an integral part of the consolidated financial statements. These estimates require the use of judgments and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses in the periods presented. We believe that the accounting estimates employed are appropriate and the resulting balances are reasonable; however, due to the inherent uncertainties in making estimates, actual results could differ from the original estimates, requiring adjustments to these balances in future periods.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents generally consist of cash, certificates of deposit, fixed deposits and money market funds with original maturities of three months or less. Certificates of deposit and fixed deposits whose original maturity is greater than three months and is one year or less are classified as short-term investments. At December 31, 2018 and 2017, certificates of deposit totaling $0.8 million were restricted in use (to collateralize letters of credit securing workers’ compensation obligations) and were classified as short-term investments on our consolidated balance sheet.
Derivative Financial Instruments and Hedging Activities	Derivative Financial Instruments and Hedging Activities We account for our derivative instruments as either assets or liabilities and carry them at fair value. For derivative instruments that hedge the exposure to variability in expected future cash flows that are designated as cash flow hedges, the gain or loss on the derivative instrument (including changes in time value for forward contracts) is reported as a component of accumulated other comprehensive income or loss in shareholders’ equity and reclassified into income in the same period or periods during which the hedged transaction affects earnings. Derivatives that do not qualify or have not been designated as hedges are adjusted to fair value through current income. See Note 5, “Derivative Financial Instruments” for additional information pertaining to our derivative instruments. We enter into contracts to purchase certain commodities used in the manufacture of our products, such as aluminum, natural gas and other raw materials. These contracts are considered to be derivative instruments under U.S. GAAP; however, these purchase contracts are not accounted for as derivatives because they qualify for the normal purchase normal sale exemption.
Cash Paid for Interest and Taxes and Non-Cash Investing Activities	Cash Paid for Interest and Taxes and Non-Cash Cash paid for interest was $43.8 million, $24.3 million and $0.3 million for the years ended December 31, 2018, 2017 and 2016. Cash paid for income taxes was $6.5 million, $11.1 million and $21.9 million for the years ended December 31, 2018, 2017 and 2016. As of December 31, 2018, 2017 and 2016, $10.3 million, $15.1 million and $4.0 million, respectively, of equipment had been purchased but not yet paid for and are included in accounts payable and accrued expenses in our consolidated balance sheets.
Accounts Receivable	Accounts Receivable Accounts receivable primarily consists of amounts that are due and payable from our customers for the sale of aluminum wheels. We evaluate the collectability of receivables each reporting period and record an allowance for doubtful accounts representing our estimate of probable losses. Additions to the allowance are charged to bad debt expense reported in selling, general and administrative expense.
Inventory	Inventory Inventories, which are categorized as raw materials, work-in-process
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are carried at cost, less accumulated depreciation. The cost of additions, improvements and interest during construction, if any, are capitalized. Our maintenance and repair costs are charged to expense when incurred. Depreciation is calculated generally on the straight-line method based on the estimated useful lives of the assets. Classification Expected Useful Life Computer equipment 3 to 5 years Production machinery and technical equipment 3 to 20 years Buildings 15 to 50 years Other equipment, operating and office equipment 3 to 20 years When property, plant and equipment is replaced, retired or disposed of, the cost and related accumulated depreciation are removed and any resulting gain or loss is recorded as a component of cost of sales or other income or expense.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The carrying amount of long-lived assets and finite-lived intangible assets to be held and used in the business is evaluated for impairment when events and circumstances warrant. If the carrying amount of a long-lived asset group is considered impaired, a loss is recorded based on the amount by which the carrying amount exceeds fair value. Fair value is determined primarily using anticipated cash flows.
Impairment of Goodwill	Impairment of Goodwill Goodwill is not amortized but is tested for impairment on at least an annual basis. Impairment testing is required more often than annually if an event or circumstance indicates that an impairment is more likely than not to have occurred. If the net book value of a reporting unit exceeds its fair value, an impairment loss is measured and recognized. We conduct our annual impairment testing as of December 31, 2018.
Foreign Currency Transactions and Translation	Foreign Currency Transactions and Translation The assets and liabilities of foreign subsidiaries that use local currency as their functional currency are translated to U.S. dollars based on the current exchange rate prevailing at each balance sheet date and any resulting translation adjustments are included in accumulated other comprehensive income (loss). The assets and liabilities of foreign subsidiaries whose local currency is not their functional currency are remeasured from their local currency to their functional currency and then translated to U.S. dollars. Revenues and expenses are translated into U.S. dollars using the average exchange rates prevailing for each period presented. Gains and losses arising from foreign currency transactions and the effects of remeasurement discussed in the preceding paragraph are recorded in other income (expense), net. We had foreign currency transaction gains (losses) of ($1.0) million, $12.9 million, ($0.4) million in 2018, 2017 and 2016, respectively.
Revenue Recognition	Revenue Recognition On January 1, 2018, we adopted ASU 2014-09, The Company maintains long term business relationships with our OEM customers and aftermarket distributors; however, there are no definitive long-term volume commitments under these arrangements. Volume commitments are limited to near-term customer requirements authorized under purchase orders or production releases generally with delivery periods of less than a month. Sales do not involve any significant financing component since customer payment is generally due 40-60 At contract inception, the Company assesses goods and services promised in its contracts with customers and identifies a performance obligation for each promise to deliver a good or service (or bundle of goods or services) that is distinct. Principal performance obligations under our customer contracts consist of the manufacture and delivery of aluminum wheels, including production wheels, service wheels and replacement wheels. As a part of the manufacture of the wheels, we develop tooling necessary to produce the wheels. Accordingly, tooling costs, which are explicitly recoverable from our customers, are capitalized as preproduction costs and amortized to cost of sales over the average life of the vehicle wheel program. Similarly, customer reimbursement for tooling costs is deferred and amortized to net sales over the average life of the vehicle wheel program. In the normal course of business, the Company’s warranties are limited to product specifications and the Company does not accept product returns unless the item is defective as manufactured. Accordingly, warranty costs are treated as a cost of fulfillment subject to accrual, rather than a performance obligation. The Company establishes provisions for both estimated returns and warranties when revenue is recognized. In addition, the Company does not typically provide customers with the right to a refund but provides for product replacement. Prices allocated to production, service and replacement wheels are based on prices established in our customer purchase orders which represent the standalone selling price. Prices for service and replacement wheels are commensurate with production wheels with adjustment for any special packaging. In addition, prices are subject to retrospective adjustment for changes in commodity prices for certain raw materials, aluminum and silicon, as well as production efficiencies and wheel weight variations from specifications used in pricing. These price adjustments are treated as variable consideration. Customer tooling reimbursement is generally based on quoted prices or cost not to exceed quoted prices. We estimate variable consideration by using the “most likely” amount estimation approach. For commodity prices, initial estimates are based on the commodity index at contract inception. Changes in commodity prices are monitored and revenue is adjusted as changes in the commodity index occur. Prices incorporate the wheel weight price component based on product specifications. Weights are monitored, and prices are adjusted as variations arise. Price adjustments due to production efficiencies are generally recognized as and when negotiated with customers. Customer contract prices are generally adjusted quarterly to incorporate retroactive price adjustments. Under the Company’s policies, shipping costs are treated as a cost of fulfillment. In addition, as permitted under a practical expedient relating to disclosure of performance obligations, the Company does not disclose remaining performance obligations under its contracts since contract terms are substantially less than a year (generally less than one month). Our revenue recognition practices and related transactions and balances are further described in Note 3, “Revenue.”
Research and Development	Research and Development Research and development costs (primarily engineering and related costs) are expensed as incurred and are included in cost of sales in the consolidated income statements. Amounts expensed during 2018, 2017 and 2016 were $5.7 million, $7.7 million and $3.8 million, respectively.
Stock-Based Compensation	Stock-Based Compensation We account for stock-based compensation using the estimated fair value recognition method. We recognize these compensation costs net of the applicable forfeiture rate on a straight-line basis for only those shares expected to vest over the requisite service period of the award, which is generally the vesting term of three years. We estimate the forfeiture rate based on our historical experience. See Note 20, “Stock-Based Compensation” for additional information concerning our stock-based compensation awards.
Income Taxes	Income Taxes We account for income taxes using the asset and liability method. The asset and liability method requires the recognition of deferred tax assets and liabilities for expected future tax consequences of temporary differences that currently exist between the tax basis and financial reporting basis of our assets and liabilities. We calculate current and deferred tax provisions based on estimates and assumptions that could differ from actual results reflected on the income tax returns filed during the following years. Adjustments based on filed returns are recorded when identified in the subsequent years. The effect on deferred taxes for a change in tax rates is recognized in income in the period that the tax rate change is enacted. In assessing the realizability of deferred tax assets, we consider whether it is more likely than not that some portion of the deferred tax assets will not be realized. A valuation allowance is provided for deferred income tax assets when, in our judgment, based upon currently available information and other factors, it is more likely than not that all or a portion of such deferred income tax assets will not be realized. The determination of the need for a valuation allowance is based on an on-going In determining when to release the valuation allowance established against our net deferred income tax assets, we consider all available evidence, both positive and negative. Consistent with our policy, the valuation allowance against our net deferred income tax assets will not be reversed until such time as we have generated three years of cumulative pre-tax pre-tax We account for uncertain tax positions utilizing a two-step more-likely-than-not more-likely-than-not Presently, we have not recorded a deferred tax liability for temporary differences related to investments in foreign subsidiaries that are essentially permanent in duration. These temporary differences may become taxable upon a repatriation of earnings from the subsidiaries or a sale or liquidation of the subsidiaries. At this time the Company does not have any plans to repatriate income from its foreign subsidiaries.
New Accounting Standards	New Accounting Standards Adoption of New Accounting Standards Accounting Standards Update (“ASU”) 2014-09, . ASU 2017-12 ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments.” ASU 2017-07, ASU 2017-01, ASU 2016-16, Intra-Entity Transfers of Assets Other than Inventory.” Accounting Standards Issued But Not Yet Adopted ASU 2017-04, ASU 2016-02, 2016-02, right-of-use 2016-02 2016-02 ASU 2018-02, 2018-02, 2018-02. ASU 2018-13, Fair Value Measurement.” Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement 2018-13 ASU 2018-14, Compensation - Retirement Benefits - Defined Benefit Plans.” Compensation - Retirement Benefits - Defined Benefit Plans - General Subtopic 715-20 2018-14
Fair Value Measurements	The Company applies fair value accounting for all financial assets and liabilities and non-financial Level 1 - Quoted prices in active markets for identical assets or liabilities. Level 2 - Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 - Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability. The carrying amounts for cash and cash equivalents, investments in certificates of deposit, accounts receivable, accounts payable and accrued expenses approximate their fair values due to the short period of time until maturity.
Derivatives, Methods of Accounting, Hedging Derivatives	Derivative Instruments and Hedging Activities We use derivatives to partially offset our exposure to foreign currency, interest rates, aluminum and other commodity risk. We may enter into forward contracts, option contracts, swaps, collars or other derivative instruments to offset some of the risk on expected future cash flows and on certain existing assets and liabilities. However, we may choose not to hedge certain exposures for a variety of reasons including, but not limited to, accounting considerations and the prohibitive economic cost of hedging particular exposures. There can be no assurance the hedges will offset more than a portion of the financial impact resulting from movements in foreign currency exchange rates, interest rates, and aluminum as well as natural gas commodity prices. To help protect gross margins from fluctuations in foreign currency exchange rates, certain of our subsidiaries, whose functional currency is the U.S. dollar or the Euro, hedge a portion of their forecasted foreign currency costs denominated in the Mexican Peso and Polish Zloty, respectively. We may hedge portions of our forecasted foreign currency exposure up to 48 months. We record all derivatives in the consolidated balance sheets at fair value. Our accounting treatment for these instruments is based on the hedge designation. The cash flow hedges that are designated as hedging instruments are recorded in Accumulated Other Comprehensive Income (“AOCI”) until the hedged item is recognized in earnings, at which point accumulated gains or losses will be recognized in earnings and classified with the underlying hedged transaction. Derivatives that are not designated as hedging instruments are adjusted to fair value through earnings in the financial statement line item to which the derivative relates. The Company has derivatives that are designated as hedging instruments as well as derivatives that did not qualify for designation as hedging instruments.
Derivatives, Methods of Accounting, Derivatives Not Designated or Qualifying as Hedges	Derivatives that are not designated as hedging instruments are adjusted to fair value through earnings in the financial statement line item to which the derivative relates.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Estimated Useful Lives of the Assets	Classification Expected Useful Life Computer equipment 3 to 5 years Production machinery and technical equipment 3 to 20 years Buildings 15 to 50 years Other equipment, operating and office equipment 3 to 20 years

Acquisition (Tables)

Acquisition (Tables)	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Summary of Purchase Price Allocation	The following is the allocation of the purchase price: (Dollars in thousands) Estimated purchase price Cash consideration $ 703,000 Non-controlling 63,200 Preliminary purchase price allocation Cash and cash equivalents 12,296 Accounts receivable 60,580 Inventories 83,901 Prepaid expenses and other current assets 11,859 Total current assets 168,636 Property and equipment 259,784 Intangible assets 205,000 Goodwill 286,249 Other assets 32,987 Total assets acquired 952,656 Accounts payable 61,883 Other current liabilities 40,903 Total current liabilities 102,786 Other long-term liabilities 83,670 Total liabilities assumed 186,456 Net assets acquired $ 766,200 Acquired intangible assets were recorded at estimated fair value, as determined through the use of the income approach, specifically the relief from royalty and multi-period excess earnings methods. The major assumptions used in arriving at the estimated identifiable intangible asset values included estimates of future cash flows, discounted at an appropriate rate of return which is based on the weighted average cost of capital for both the Company and other market participants. The useful lives for intangible assets were determined based upon the remaining useful economic lives of the intangible assets that are expected to contribute directly or indirectly to our future cash flows. The estimated fair value of intangible assets and related useful lives as included in the purchase price allocation include: Estimated Estimated (Dollars in thousands) Brand name $ 9,000 4-6 Technology 15,000 4-6 Customer relationships 167,000 7-11 Trade names 14,000 Indefinite $ 205,000
Summary of Unaudited Pro Forma Information	The following unaudited combined pro forma information is for informational purposes only. The pro forma information is not necessarily indicative of what the combined Company’s results actually would have been had the acquisition been completed as of the beginning of the periods as indicated. In addition, the unaudited pro forma information does not purport to project the future results of the combined Company. Twelve Months Ended December 31, December 31, Proforma Proforma (Dollars in thousands) Proforma combined sales $ 1,351,799 $ 1,246,248 Proforma net income $ 17,692 $ 38,809

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Summary of Opening and Closing Balances of Company's Receivables and Current and Long-term Contract Liabilities	The opening and closing balances of the Company’s receivables and current and long-term contract liabilities are as follows (in thousands): December 31, January 1, Change Customer receivables $ 97,566 $ 150,151 $ (52,585 ) Contract liabilities — current 5,810 5,736 74 Contract liabilities — noncurrent 8,354 5,222 3,132

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Items Measured at Fair Value	The following tables categorize items measured at fair value at December 31, 2018 and 2017: Fair Value Measurement at Reporting Date Using December 31, 2018 Quoted Prices in Significant Other Significant (Dollars in thousands) Assets Certificates of deposit $ 750 $ — $ 750 $ — Cash surrender value 8,057 — 8,057 — Derivative contracts 4,218 — 4,218 — Total 13,025 — 13,025 — Liabilities Derivative contracts 8,836 — 8,836 Embedded derivative liability 3,134 — — 3,134 Total $ 11,970 $ — $ 8,836 $ 3,134 Fair Value Measurement at Reporting Date Using December 31, 2017 Quoted Prices in Significant Other Significant (Dollars in thousands) Assets Certificates of deposit $ 750 — $ 750 — Cash surrender value 8,040 — 8,040 — Derivative contracts 6,342 — 6,342 — Total 15,132 — 15,132 — Liabilities Derivative contracts 16,106 — 16,106 — Embedded derivative liability 4,685 — — 4,685 Total $ 20,791 — $ 16,106 $ 4,685
Summary of Changes in Level 3 Fair Value Measurement of Embedded Derivative Liability	The following table summarizes the changes during 2018 and 2017 in level 3 fair value measurement of the embedded derivative liability relating to the redeemable preferred stock issued May 22, 2017 in connection with the acquisition of our European operations: January 1, 2017 – December 31, 2018 (Dollars in thousands) Beginning fair value – January 1, 2017 $ — Change in fair value of redeemable preferred stock embedded derivative liability 4,685 Ending fair value – December 31, 2017 4,685 Change in fair value of redeemable preferred stock embedded derivative liability (3,480 ) Effect of redeemable preferred stock modification 1,929 Ending fair value – December 31, 2018 3,134
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	The estimated fair value, as well as the carrying value, of the Company’s debt instruments are shown below (in thousands): December 31, December 31, (Dollars in thousands) Estimated aggregate fair value $ 624,943 $ 704,005 Aggregate carrying value (1) 684,922 707,864 (1) Long-term debt excluding the impact of unamortized debt issuance costs.

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Fair Value of Derivatives by Balance Sheet Line Item	The following tables display the fair value of derivatives by balance sheet line item at December 31, 2018 and December 31, 2017: December 31, 2018 Other Other Non-current Accrued Other Non-current (Dollars in thousands) Foreign exchange forward contracts designated as hedging instruments $ 2,599 1,011 659 6,202 Foreign exchange forward contracts not designated as hedging instruments 333 — 207 — Aluminum forward contracts designated as hedging instruments — — 927 — Cross currency swap not designated as hedging instrument — — 227 — Natural gas forward contracts designated as hedging instruments 275 — 355 — Interest rate swap contracts designated as hedging instruments — — 131 128 Embedded derivative liability — — — 3,134 Total derivative financial instruments $ 3,207 1,011 2,506 9,464 December 31, 2017 Other Other Non-current Accrued Other Non-current (Dollars in thousands) Foreign exchange forward contracts and collars designated as hedging instruments $ 3,065 723 4,922 8,405 Foreign exchange forward contracts not designated as hedging 721 — 206 — Aluminum forward contracts not designated as hedging instruments 1,833 — — — Cross currency swap not designated as hedging instrument — — 1,467 1,106 Embedded derivative liability — — — 4,685 Total derivative financial instruments $ 5,619 723 6,595 14,196
Summary of Notional Amount and Estimated Fair Value of Derivative Financial Instruments	The following table summarizes the notional amount and estimated fair value of our derivative financial instruments: December 31, 2018 December 31, 2017 Notional Fair Notional Fair (Dollars in thousands) Foreign currency forward contracts and collars designated as hedging instruments $ 467,253 $ (3,251 ) $ 397,744 $ (9,539 ) Foreign exchange forward contracts not designated as hedging instruments 45,905 126 23,305 515 Aluminum forward contracts not designated as hedges 10,810 (927 ) 15,564 1,833 Cross currency swap not designated as hedging instrument 12,151 (227 ) 36,454 (2,573 ) Natural gas forward contracts designated as hedging instrument 2,165 (80 ) — — Interest rate swap contracts designated as hedging instrument 90,000 (259 ) — — Total derivative financial instruments $ 628,284 $ (4,618 ) $ 473,067 $ (9,764 )
Summary of Gain or Loss Recognized in AOCI (Loss)	The following tables summarize the gain or loss recognized in accumulated other comprehensive income (loss) (“AOCI”) as of December 31, 2018, 2017 and 2016 the amounts reclassified from AOCI into earnings and the amounts recognized directly into earnings for the years ended December 31, 2018, 2017 and 2016: Year ended December 31, 2018 Amount of Gain or (Loss) Amount of Pre-tax Gain or Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ 5,293 $ 728 $ (406 ) Total $ 5,293 $ 728 $ (406 ) Year ended December 31, 2017 Amount of Gain or (Loss) Amount of Pre-tax Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ 7,603 $ (4,539 ) $ (538 ) Total $ 7,603 $ (4,539 ) $ (538 ) Year ended December 31, 2016 Amount of Gain or (Loss) Amount of Pre-tax Amount of Pre-tax Gain or (Dollars in thousands) Derivative Contracts $ (6,812 ) $ (13,597 ) $ (156 ) Total $ (6,812 ) $ (13,597 ) $ (156 )

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Summary of Net Sales and Results of Operations and Total Assets by Reportable Segment	(Dollars in thousands) Net Sales Income from Operations 2018 2017 2016 2018 2017 2016 North America $ 800,383 $ 732,418 $ 732,677 $ 29,702 $ 9,808 $ 54,602 Europe 701,444 375,637 — 56,103 11,710 — $ 1,501,827 $ 1,108,055 $ 732,677 $ 85,805 $ 21,518 $ 54,602 (Dollars in thousands) Depreciation and Capital Expenditures 2018 2017 2016 2018 2017 2016 North America $ 33,588 $ 35,931 $ 34,261 $ 37,476 $ 47,493 $ 39,575 Europe 61,468 33,404 — 40,221 23,444 — $ 95,056 $ 69,335 $ 34,261 $ 77,697 $ 70,937 $ 39,575 (Dollars in thousands) Property, Plant, and Goodwill and 2018 2017 2018 2017 North America $ 249,791 $ 245,178 $ — $ — Europe 282,976 291,508 459,803 508,278 $ 532,767 $ 536,686 $ 459,803 $ 508,278 (Dollars in thousands) Total Assets 2018 2017 North America $ 484,682 $ 519,192 Europe 966,934 1,032,060 $ 1,451,616 $ 1,551,252
Net Sales by Geographic Location	Net sales by geographic location: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Net sales: U.S. $ 127,178 $ 124,711 $ 120,395 Mexico 673,205 607,707 612,282 Germany 279,631 155,227 — Poland 421,813 220,410 — Consolidated net sales $ 1,501,827 $ 1,108,055 $ 732,677

Accounts Receivable (Tables)

Accounts Receivable (Tables)	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Summary of Accounts Receivable	December 31, 2018 2017 (Dollars in thousands) Trade receivables $ 101,864 $ 152,476 Other receivables 7,083 10,016 108,947 162,492 Allowance for doubtful accounts (4,298 ) (2,325 ) Accounts receivable, net $ 104,649 $ 160,167
Schedule of Revenues by Major Customers	2018 2017 2016 Ford 18 % 22 % 38 % GM 18 % 20 % 30 % VW Group 12 % 9 % <1 % Toyota 8 % 9 % 14 %

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Summary of Inventories	December 31, 2018 2017 (Dollars in thousands) Raw materials $ 49,571 $ 59,353 Work in process 42,886 48,803 Finished goods 83,121 65,843 Inventories, net $ 175,578 $ 173,999

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	December 31, 2018 2017 (Dollars in thousands) Land and buildings $ 140,471 $ 136,918 Machinery and equipment 769,451 720,175 Leasehold improvements and others 12,883 12,192 Construction in progress 67,559 58,753 990,364 928,038 Accumulated depreciation (457,597 ) (391,352 ) Property, plant and equipment, net $ 532,767 $ 536,686

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Finite-Lived and Indefinite-Lived Intangible Assets	Following is a summary of the Company’s finite-lived and indefinite-lived intangible assets and goodwill as of December 31, 2018 and 2017. Gross Accumulated Currency Net Remaining Year Ended December 31, 2018 (Dollars in thousands) Brand name $ 9,000 $ (2,979 ) $ 237 $ 6,258 4-5 Technology 15,000 (4,964 ) 394 10,430 3-5 Customer relationships 167,000 (33,468 ) 3,823 137,355 5-10 Total finite 191,000 (41,411 ) 4,454 154,043 Trade names 14,000 — 326 14,326 Indefinite Total intangibles $ 205,000 $ (41,411 ) $ 4,780 $ 168,369 Beginning Currency Ending Year Ended December 31, 2018 (Dollars in thousands) Goodwill $ 304,805 $ (13,371 ) $ 291,434 Gross Accumulated Currency Net Remaining Year Ended December 31, 2017 (Dollars in thousands) Brand name $ 9,000 $ (1,091 ) $ 581 $ 8,490 5-6 Technology 15,000 (1,818 ) 968 14,150 4-6 Customer relationships 167,000 (12,259 ) 11,005 165,746 6-11 Total finite 191,000 (15,168 ) 12,554 188,386 Trade names 14,000 — 1,087 15,087 Indefinite Total intangibles $ 205,000 $ (15,168 ) $ 13,641 $ 203,473 Beginning Currency Ending Year Ended December 31, 2017 (Dollars in thousands) Goodwill $ 286,249 $ 18,556 $ 304,805

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Summary of Long-Term Debt and Related Weighted Average Interest Rates	A summary of long-term debt and the related weighted average interest rates is shown below: December 31, 2018 Debt Instrument Total Debt (1) Total Weighted Term Loan Facility $ 382,800 $ (13,078 ) $ 369,722 6.3 % 6.00% Senior Notes due 2025 286,100 (7,366 ) 278,734 6.0 % Other 16,022 — 16,022 2.2 % $ 684,922 $ (20,444 ) 664,478 Less: Current portion (3,052 ) Long-term debt $ 661,426 December 31, 2017 Debt Instrument Total Debt (1) Total Weighted Term Loan Facility $ 386,800 $ (15,802 ) $ 370,998 5.6 % 6.00% Senior Notes due 2025 300,250 (8,510 ) 291,740 6.0 % Other 20,814 — 20,814 1.0 % $ 707,864 $ (24,312 ) 683,552 Less: Current portion (4,000 ) Long-term debt $ 679,552 (1) Unamortized portion

European Non-Controlling Rede_2

European Non-Controlling Redeemable Equity (Tables)	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest [Abstract]
Summary of Redeemable Noncontrolling Interests	The following table summarizes the European non-controlling Balance at December 31, 2017 $ — Reclassification of non-controlling 51,943 Redemption value adjustment 3,625 Dividends accrued 1,512 Dividends paid (964 ) Translation adjustment (3,219 ) Purchase of shares (39,048 ) Balance at December 31, 2018 $ 13,849

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Year Ended December 31, 2018 2017 2016 (Dollars in thousands, except per share amounts) Basic Earnings Per Share: Reported net income (loss) attributable to Superior $ 25,961 $ (6,203 ) $ 41,381 Less: Redeemable preferred stock dividends and accretion (32,462 ) (18,912 ) — Add: Preferred stock modification 15,257 — — Less: European non-controlling (1,512 ) — — Basic numerator $ 7,244 $ (25,115 ) $ 41,381 Basic earnings (loss) per share $ 0.29 $ (1.01 ) $ 1.63 Weighted average shares outstanding-Basic 24,994 24,929 25,439 Diluted Earnings Per Share: Reported net income (loss) attributable to Superior $ 25,961 $ (6,203 ) $ 41,381 Less: Redeemable preferred stock dividends and accretion (32,462 ) (18,912 ) — Add: Preferred stock modification 15,257 — — Less: European non-controlling (1,512 ) — — Diluted numerator $ 7,244 $ (25,115 ) $ 41,381 Diluted earnings (loss) per share $ 0.29 $ (1.01 ) $ 1.62 Weighted average shares outstanding-Basic 24,994 24,929 25,439 Dilutive effect of common share equivalents 161 — 100 Weighted average shares outstanding-Diluted 25,155 24,929 25,539

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Before Income Taxes From Domestic and International Jurisdictions	Income before income taxes from domestic and international jurisdictions is comprised of the following: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Income before income taxes: Domestic $ (44,058 ) $ (63,716 ) $ 18,499 Foreign 76,310 64,582 36,222 $ 32,252 $ 866 $ 54,721
Provision for Income Taxes	The provision for income taxes is comprised of the following: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Current taxes Federal $ 3,714 $ 6,121 $ (5,017 ) State 127 (390 ) 450 Foreign (11,180 ) (12,564 ) (10,639 ) Total current taxes (7,339 ) (6,833 ) (15,206 ) Deferred taxes Federal (919 ) (4,387 ) (1,199 ) State 521 1,492 (332 ) Foreign 1,446 2,853 3,397 Total deferred taxes 1,048 (42 ) 1,866 Income tax provision $ (6,291 ) $ (6,875 ) $ (13,340 )
Reconciliation of the U.S. Federal Tax Rate	The following is a reconciliation of the U.S. federal tax rate to our effective income tax rate: Year Ended December 31, 2018 2017 2016 Statutory rate (21.0 )% (35.0 )% (35.0 )% State tax provisions, net of federal income tax benefit 6.4 263.4 (6.3 ) Tax credits 1.3 88.9 0.6 Foreign income taxes at rates other than the statutory rate 16.8 1,206.6 11.7 Valuation allowance and other (28.0 ) (138.0 ) 5.1 Changes in tax liabilities, net (0.6 ) (11.3 ) 0.5 Share based compensation (1.0 ) (61.5 ) (1.2 ) Transaction costs — (372.2 ) — US Tax Reform implementation 10.9 (1,918.7 ) — US Tax on non-US (16.1 ) — — Non-taxable 16.3 152.6 — Other (4.5 ) 31.3 0.2 Effective income tax rate (19.5 )% (793.9 )% (24.4 )%
Summary of Deferred Income Tax Assets and Liabilities	Tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and deferred liabilities are as follows: December 31, 2018 2017 (Dollars in thousands) Deferred income tax assets: Accrued liabilities $ 8,117 $ 2,445 Hedging and foreign currency losses (1,163 ) 2,034 Deferred compensation 8,021 8,628 Inventory reserves 3,984 2,954 Net loss carryforwards and credits 51,552 69,018 Interest carryforwards 11,269 — Competent authority deferred tax assets and other foreign timing differences 6,749 6,939 Other (3,921 ) (830 ) Total before valuation allowance 84,608 91,188 Valuation allowance (16,576 ) (7,634 ) Net deferred income tax assets 68,032 83,554 Deferred income tax liabilities: Intangibles, property, plant and equipment and other (44,591 ) (57,791 ) Deferred income tax liabilities (44,591 ) (57,791 ) Net deferred income tax assets $ 23,441 $ 25,763 The classification of our net deferred tax asset is shown below: December 31, 2018 2017 (Dollars in thousands) Long-term deferred income tax assets $ 42,105 $ 54,302 Long-term deferred income tax liabilities (18,664 ) (28,539 ) Net deferred tax asset $ 23,441 $ 25,763
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amounts of these tax benefits is as follows: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Beginning balance $ 33,054 $ 3,446 $ 7,318 Increases (decreases) due to foreign currency translations (2,018 ) — — Increases (decreases) as a result of positions taken during: Prior periods — — (3,872 ) Current period — 29,773 — Expiration of applicable statutes of limitation — (165 ) — Ending balance $ 31,036 $ 33,054 $ 3,446

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Schedule of Future Minimum Rental Payments Under Operating Leases	The following are summarized future minimum payments under our operating leases: Year Ended December 31, Operating (Dollars in thousands) 2019 $ 4,249 2020 3,232 2021 2,870 2022 2,635 2023 2,346 Thereafter 7,647 $ 22,979

Retirement Plans (Tables)

Retirement Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Summary of Changes in Plan Assets and Plan Benefit Obligations	The following table summarizes the changes in plan assets and plan benefit obligations: Year Ended December 31, 2018 2017 (Dollars in thousands) Change in benefit obligation Beginning benefit obligation $ 29,759 $ 27,612 Interest cost 1,086 1,189 Actuarial (gain) loss (2,486 ) 2,300 Benefit payments (1,406 ) (1,342 ) Ending benefit obligation $ 26,953 $ 29,759
Summary of Defined Benefit Plans	Year Ended December 31, 2018 2017 (Dollars in thousands) Change in plan assets Fair value of plan assets at beginning of year $ — $ — Employer contribution 1,406 1,342 Benefit payments (1,406 ) (1,342 ) Fair value of plan assets at end of year $ — $ — Funded status $ (26,953 ) $ (29,759 ) Amounts recognized in the consolidated balance sheets consist of: Accrued expenses (1,392 ) (1,407 ) Other non-current (25,561 ) (28,352 ) Net amount recognized $ (26,953 ) $ (29,759 ) Amounts recognized in accumulated other comprehensive loss consist of: Net actuarial loss $ 4,799 $ 7,722 Prior service cost (1 ) (1 ) Net amount recognized, before tax effect $ 4,798 $ 7,721 Weighted average assumptions used to determine benefit obligations: Discount rate 4.4 % 3.7 % Rate of compensation increase 3.0 % 3.0 %
Summary of Components of Net Periodic Pension Cost	Components of net periodic pension cost are described in the following table: Year Ended December 31, 2018 2017 2016 (Dollars in thousands) Components of net periodic pension cost: Interest cost 1,086 1,189 1,216 Amortization of actuarial loss 438 369 335 Net periodic pension cost 1,524 1,558 $ 1,551 Weighted average assumptions used to determine net periodic pension cost: Discount rate 3.7 % 4.4 % 4.4 % Rate of compensation increase 3.0 % 3.0 % 3.0 %
Summary of Expected Benefit Payments	Benefit payments during the next ten years, which reflect applicable future service, are as follows: Year Ended December 31, Amount (Dollars in thousands) 2019 $ 1,422 2020 $ 1,484 2021 $ 1,457 2022 $ 1,495 2023 $ 1,472 Years 2024 to 2028 $ 8,448
Periodic Pension Cost, Next Fiscal Year	The following is an estimate of the components of net periodic pension cost in 2019: Estimated Year Ended December 31, 2019 (Dollars in thousands) Interest cost 1,144 Amortization of actuarial loss 209 Estimated 2019 net periodic pension cost $ 1,353

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Schedule of Accrued Liabilities	December 31, 2018 2017 (Dollars in thousands) Payroll and related benefits $ 23,503 $ 27,954 Insurance Reserves 1,120 590 Taxes, other than income taxes 8,115 9,419 Current portion of derivative liability 2,506 6,595 Dividends and interest 4,197 7,322 Deferred tooling revenue 5,810 4,654 Current portion of executive retirement liabilities 1,392 1,407 Professional Fees 4,750 3,674 Warranty Liability 437 872 Other 13,832 6,299 Accrued liabilities $ 65,662 $ 68,786

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Restricted Performance Stock Unit and Equity Incentive Activity	Equity Incentive Awards Restricted Weighted Performance Weighted Options Weighted Balance at December 31, 2017 169,266 $ 22.27 239,674 $ 22.58 145,625 $ 18.96 Granted 204,003 $ 15.91 325,526 $ 17.12 — — Settled (66,138 ) $ 22.67 — — (4,500 ) $ 15.17 Forfeited or expired (123,405 ) $ 18.98 (268,677 ) $ 19.8 (82,125 ) $ 19.62 Balance at December 31, 2018 183,726 $ 17.26 296,523 $ 19.1 59,000 $ 18.33 Vested or expected to vest at December 31, 2018 183,726 111,071 59,000

Quarterly Financial Data (Table

Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	(Dollars in thousands, except per share amounts) Year 2018 First Second Third Fourth Year Net sales $ 386,448 $ 388,944 $ 347,612 $ 378,823 $ 1,501,827 Gross profit $ 49,991 $ 53,559 $ 23,673 $ 36,304 $ 163,527 Income from operations $ 27,634 $ 31,270 $ 7,688 $ 19,213 $ 85,805 Consolidated income (loss) before income taxes $ 13,687 $ 12,930 $ (7,714 ) $ 13,349 $ 32,252 Income tax (provision) benefit $ (3,370 ) $ (4,795 ) $ 7,051 $ (5,177 ) $ (6,291 ) Consolidated net income (loss) $ 10,317 $ 8,135 $ (663 ) $ 8,172 $ 25,961 Income (loss) per share (1) Basic (1) $ 0.07 $ (0.02 ) $ (0.37 ) $ 0.61 $ 0.29 Diluted (1) $ 0.07 $ (0.02 ) $ (0.37 ) $ 0.61 $ 0.29 Dividends declared per share $ 0.09 $ 0.09 $ 0.09 $ 0.09 $ 0.36 Statement of Comprehensive Income: Other comprehensive income (loss), net of tax (1) $ 34,901 $ (53,178 ) $ 21,960 $ (20,057 ) $ (16,374 ) (1) Subsequent to the issuance of the September 30, 2018 interim financial statements, the Company identified an error related to the classification of foreign currency translation adjustments associated with the European non-controlling non-controlling Year 2017 First Second Third Fourth Year Net sales $ 174,220 $ 240,628 $ 331,404 $ 361,803 $ 1,108,055 Gross profit $ 19,204 $ 20,105 $ 23,893 $ 39,695 $ 102,897 Income (loss) from operations $ 3,944 $ (1,998 ) $ 5,758 $ 13,814 $ 21,518 Consolidated income (loss) before income taxes $ 3,300 $ (9,241 ) $ (501 ) $ 7,308 $ 866 Income tax (provision) benefit $ (198 ) $ 1,722 $ 3,355 $ (11,754 ) $ (6,875 ) Consolidated net income (loss) $ 3,102 $ (7,519 ) $ 2,854 $ (4,446 ) $ (6,009 ) Less: Net loss (income) attributable to non-controlling — $ 247 $ (239 ) $ (202 ) $ (194 ) Net income (loss) attributable to Superior $ 3,102 $ (7,272 ) $ 2,615 $ (4,648 ) $ (6,203 ) Income (loss) per share: Basic $ 0.12 $ (0.41 ) $ (0.22 ) $ (0.50 ) $ (1.01 ) Diluted $ 0.12 $ (0.41 ) $ (0.22 ) $ (0.50 ) $ (1.01 ) Dividends declared per share $ 0.18 $ 0.09 $ 0.09 $ 0.09 $ 0.45

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 25, 2016USD ($)	Jan. 01, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash and investments, current	$ 0.8	$ 0.8
Cash paid for interest	43.8	24.3	$ 0.3
Cash paid for income taxes	6.5	11.1	21.9
Noncash or part noncash acquisition, fixed assets acquired	10.3	15.1	4
Foreign currency transaction gain (loss), before tax	(1)	12.9	(0.4)
Research and development expense	$ 5.7	$ 7.7	$ 3.8
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Recognition of lease obligations				$ 20
Supplier Concentration Risk [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vendors accounting for more than ten percent of aluminum purchases	3

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Estimated Useful Lives of the Assets. (Detail)	12 Months Ended
	Dec. 31, 2018
Minimum [Member] | Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	3 years
Minimum [Member] | Production Machinery and Technical Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	3 years
Minimum [Member] | Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	15 years
Minimum [Member] | Other Equipment, Operating and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	3 years
Maximum [Member] | Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	5 years
Maximum [Member] | Production Machinery and Technical Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	20 years
Maximum [Member] | Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	50 years
Maximum [Member] | Other Equipment, Operating and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	20 years

Acquisition - Additional Inform

Acquisition - Additional Information (Detail) $ in Thousands	May 30, 2017USD ($)	Dec. 31, 2018USD ($)€ / sharesshares	Dec. 31, 2017USD ($)	Dec. 25, 2016USD ($)	Dec. 31, 2018€ / shares	Dec. 31, 2018zł / shares	Jun. 30, 2018USD ($)
Business Acquisition [Line Items]
Percentage of voting interest acquired	92.30%
Exchange rate (dollar per polish zloty)	3.74193
Statutory rate		21.00%	35.00%	35.00%
Noncontrolling interests			$ 51,943
Goodwill		$ 291,434	$ 304,805	$ 286,249
Domination and Profit Loss Transfer Agreement [Member]
Business Acquisition [Line Items]
Exchange rate (dollar per polish zloty)		3.74193
Share price per share | (per share)					€ 62.18	zł 264
Guaranteed annual dividend for each share that is not tendered | € / shares		$ 3.38
Statutory rate		4.12%
Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Cash consideration	$ 703,000
Remaining shares tendered | shares		12,213,079
Business acquisition, percentage of ownership interests acquired		98.50%
Goodwill	$ 286,249
Domination and Profit Loss Transfer Agreement [Member]
Business Acquisition [Line Items]
Noncontrolling interests		$ 51,900
Europe [Member] | Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Goodwill							$ 286,200

Acquisition - (Schedule of Asse

Acquisition - (Schedule of Assets and Liabilities Acquired) (Detail) - USD ($) $ in Thousands	May 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Business Acquisition [Line Items]
Goodwill		$ 291,434	$ 304,805	$ 286,249
Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Cash consideration	$ 703,000
Non-controlling interest	63,200
Cash and cash equivalents	12,296
Accounts receivable	60,580
Inventories	83,901
Prepaid expenses and other current assets	11,859
Total current assets	168,636
Property and equipment	259,784
Intangible assets	205,000
Goodwill	286,249
Other assets	32,987
Total assets acquired	952,656
Accounts payable	61,883
Other current liabilities	40,903
Total current liabilities	102,786
Other long-term liabilities	83,670
Total liabilities assumed	186,456
Net assets acquired	$ 766,200

Acquisition (Schedule of Intang

Acquisition (Schedule of Intangibles Acquired) (Detail) $ in Thousands	May 30, 2017USD ($)
Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Intangible assets	$ 205,000
Uniwheels Acquisition [Member] | Trade Names [Member]
Business Acquisition [Line Items]
Indefinite-lived intangibles acquired	14,000
Brand Name [Member] | Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Finite-lived intangibles acquired	9,000
Technology [Member] | Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Finite-lived intangibles acquired	15,000
Customer Relationships [Member] | Uniwheels Acquisition [Member]
Business Acquisition [Line Items]
Finite-lived intangibles acquired	$ 167,000
Minimum [Member] | Brand Name [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	4 years
Minimum [Member] | Technology [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	4 years
Minimum [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	7 years
Maximum [Member] | Brand Name [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	6 years
Maximum [Member] | Technology [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	6 years
Maximum [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired intangible useful lives	11 years

Acquisition Acquisition (ProFor

Acquisition Acquisition (ProForma) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 25, 2016
Business Combinations [Abstract]
Proforma combined sales	$ 1,351,799	$ 1,246,248
Proforma net income	$ 17,692	$ 38,809

Revenue - Summary of Opening an

Revenue - Summary of Opening and Closing Balances of Company's Receivables and Current and Long-term Contract Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer receivables	$ 97,566
Contract liabilities - current	5,810
Contract liabilities - noncurrent	8,354
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer receivables		$ 150,151
Contract liabilities - current		5,736
Contract liabilities - noncurrent		$ 5,222
Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer receivables	(52,585)
Contract liabilities - current	74
Contract liabilities - noncurrent	$ 3,132

Revenue - Additional Informatio

Revenue - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Tooling Reimbursement [Member]
Revenue From Contract With Customers [Line Items]
Deferred revenue, revenue recognized	$ 8.5
Price Adjustments [Member]
Revenue From Contract With Customers [Line Items]
Deferred revenue, revenue recognized	$ 2.8

Fair Value Measurements - Recur

Fair Value Measurements - Recurring (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Liabilities
Embedded derivative liability	$ 3,134	$ 4,685
Recurring [Member]
Assets
Cash surrender value	8,057	8,040
Derivative contracts	4,218	6,342
Total	13,025	15,132
Liabilities
Derivative contracts	8,836	16,106
Embedded derivative liability	3,134	4,685
Total	11,970	20,791
Recurring [Member] | Certificates of Deposit [Member]
Assets
Certificates of deposit	750	750
Recurring [Member] | Level 2 [Member]
Assets
Cash surrender value	8,057	8,040
Derivative contracts	4,218	6,342
Total	13,025	15,132
Liabilities
Derivative contracts	8,836	16,106
Total	8,836	16,106
Recurring [Member] | Level 2 [Member] | Certificates of Deposit [Member]
Assets
Certificates of deposit	750	750
Recurring [Member] | Level 3 [Member]
Liabilities
Embedded derivative liability	3,134	4,685
Total	$ 3,134	$ 4,685

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Changes in Level 3 Fair Value Measurement of Embedded Derivative Liability (Detail) - Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Change in fair value:
Beginning balance	$ 4,685
Change in fair value of redeemable preferred stock embedded derivative liability	(3,480)	$ 4,685
Effect of redeemable preferred stock modification	1,929
Ending balance	$ 3,134	$ 4,685

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Carrying Values and Estimated Fair Values of Debt Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Estimate of Fair Value Measurement [Member]
Derivatives, Fair Value [Line Items]
Long-term debt fair value	$ 624,943	$ 704,005
Aggregate Carrying Value [Member]
Derivatives, Fair Value [Line Items]
Long-term debt fair value	$ 684,922	$ 707,864

Derivative Financial Instrume_3

Derivative Financial Instruments - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018USD ($)$ / shares
Derivatives, Fair Value [Line Items]
Derivative instruments objectives	We use derivatives to partially offset our exposure to foreign currency, interest rates, aluminum and other commodity risk. We may enter into forward contracts, option contracts, swaps, collars or other derivative instruments to offset some of the risk on expected future cash flows and on certain existing assets and liabilities.
Maximum length of time, foreign currency cash flow hedge	48 months
Convertible Preferred Stock, Redemption Value	$ 300,000,000
Price Volatility [Member]
Derivatives, Fair Value [Line Items]
Dividend yield rate	0.58
Expected Dividend Rate [Member]
Derivatives, Fair Value [Line Items]
Dividend yield rate	0.075
Minimum [Member] | Expected Term [Member]
Derivatives, Fair Value [Line Items]
Valuation scenario term	3 years
Minimum [Member] | Risk Free Interest Rate [Member]
Derivatives, Fair Value [Line Items]
Dividend yield rate	0.025
Maximum [Member] | Expected Term [Member]
Derivatives, Fair Value [Line Items]
Valuation scenario term	6 years 8 months 12 days
Maximum [Member] | Risk Free Interest Rate [Member]
Derivatives, Fair Value [Line Items]
Dividend yield rate	0.026
Embedded derivative liability [Member]
Derivatives, Fair Value [Line Items]
Redemption per share | $ / shares	$ 56.324
Debt instrument face value	$ 150,000,000
Convertible Preferred Stock, Redemption Value	$ 300,000,000
Risky bond rate	22.00%

Derivative Financial Instrume_4

Derivative Financial Instruments - Summary of Fair Value of Derivatives by Balance Sheet Line Item (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	$ 3,207	$ 5,619
Other Non-current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	1,011	723
Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	2,506	6,595
Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	9,464	14,196
Designated as Hedging Instrument [Member] | Other Current Assets [Member] | Natural Gas [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	275
Designated as Hedging Instrument [Member] | Accrued Liabilities [Member] | Natural Gas [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	355
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	2,599	3,065
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Designated as Hedging Instrument [Member] | Other Non-current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	1,011	723
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	659	4,922
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Designated as Hedging Instrument [Member] | Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	6,202	8,405
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	333	721
Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member] | Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	207	206
Aluminum Forward Contracts [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	927
Aluminum Forward Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets		1,833
Cross Currency Swap Not Designated as Hedging Instrument [Member] | Not Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	227	1,467
Cross Currency Swap Not Designated as Hedging Instrument [Member] | Not Designated as Hedging Instrument [Member] | Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities		1,106
Interest Rate Swap Contracts Designated as Hedges [Member] | Designated as Hedging Instrument [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	131
Interest Rate Swap Contracts Designated as Hedges [Member] | Designated as Hedging Instrument [Member] | Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	128
Embedded derivative liability [Member] | Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	$ 3,134
Embedded derivative liability [Member] | Not Designated as Hedging Instrument [Member] | Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities		$ 4,685

Derivative Financial Instrume_5

Derivative Financial Instruments - Summary of Notional Amount and Estimated Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	$ 628,284	$ 473,067
Derivative, Fair Value, Net	(4,618)	(9,764)
Designated as Hedging Instrument [Member] | Natural Gas [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	2,165
Derivative, Fair Value, Net	(80)
Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	467,253	397,744
Derivative, Fair Value, Net	(3,251)	(9,539)
Designated as Hedging Instrument [Member] | Interest Rate Swap Contracts Designated as Hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	90,000
Derivative, Fair Value, Net	(259)
Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts and Collars Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	45,905	23,305
Derivative, Fair Value, Net	126	515
Not Designated as Hedging Instrument [Member] | Aluminum Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	10,810	15,564
Derivative, Fair Value, Net	(927)	1,833
Not Designated as Hedging Instrument [Member] | Cross Currency Swap Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	12,151	36,454
Derivative, Fair Value, Net	$ (227)	$ (2,573)

Derivative Financial Instrume_6

Derivative Financial Instruments - Summary of Gain or Loss Recognized in AOCI (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Recognized in AOCI on Derivatives (Effective Portion), Net of Tax	$ 5,293	$ 7,603	$ (6,812)
Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	728	(4,539)	(13,597)
Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing)	(406)	(538)	(156)
Derivative [Member]
Derivatives, Fair Value [Line Items]
Amount of Gain or (Loss) Recognized in AOCI on Derivatives (Effective Portion), Net of Tax	5,293	7,603	(6,812)
Amount of Pre-tax Gain or (Loss) Reclassified from AOCI into Income (Effective Portion)	728	(4,539)	(13,597)
Amount of Pre-tax Gain or (Loss) Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing)	$ (406)	$ (538)	$ (156)

Business Segments - Summary of

Business Segments - Summary of Net Sales and Results of Operations and Total Assets by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES	$ 378,823	$ 347,612	$ 388,944	$ 386,448	$ 361,803	$ 331,404	$ 240,628	$ 174,220	$ 1,501,827	$ 1,108,055	$ 732,677
Income from operations	19,213	$ 7,688	$ 31,270	$ 27,634	13,814	$ 5,758	$ (1,998)	$ 3,944	85,805	21,518	54,602
Depreciation and Amortization									95,056	69,335	34,261
Capital Expenditures									77,697	70,937	39,575
Property, plant, and equipment, net	532,767				536,686				532,767	536,686
Goodwill and intangibles	459,803				508,278				459,803	508,278
Total assets	1,451,616				1,551,252				1,451,616	1,551,252
North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									800,383	732,418	732,677
Income from operations									29,702	9,808	54,602
Depreciation and Amortization									33,588	35,931	34,261
Capital Expenditures									37,476	47,493	$ 39,575
Property, plant, and equipment, net	249,791				245,178				249,791	245,178
Total assets	484,682				519,192				484,682	519,192
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									701,444	375,637
Income from operations									56,103	11,710
Depreciation and Amortization									61,468	33,404
Capital Expenditures									40,221	23,444
Property, plant, and equipment, net	282,976				291,508				282,976	291,508
Goodwill and intangibles	459,803				508,278				459,803	508,278
Total assets	$ 966,934				$ 1,032,060				$ 966,934	$ 1,032,060

Business Segments - Net Sales b

Business Segments - Net Sales by Geographic Location (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES	$ 378,823	$ 347,612	$ 388,944	$ 386,448	$ 361,803	$ 331,404	$ 240,628	$ 174,220	$ 1,501,827	$ 1,108,055	$ 732,677
U.S. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									127,178	124,711	120,395
Mexico [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									673,205	607,707	$ 612,282
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									279,631	155,227
Poland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
NET SALES									$ 421,813	$ 220,410

Accounts Receivable - Summary o

Accounts Receivable - Summary of Accounts Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Trade receivables	$ 101,864	$ 152,476
Other receivables	7,083	10,016
Accounts receivable, gross	108,947	162,492
Allowance for doubtful accounts	(4,298)	(2,325)
Accounts receivable, net	$ 104,649	$ 160,167

Accounts Receivable - Schedule

Accounts Receivable - Schedule of Revenues by Major Customers (Detail) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Ford [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	18.00%	22.00%	38.00%
General Motors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	18.00%	20.00%	30.00%
Volkswagen [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	12.00%	9.00%	1.00%
Toyota [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	8.00%	9.00%	14.00%

Accounts Receivable - Additiona

Accounts Receivable - Additional Information (Detail) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
General Motors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	18.00%	20.00%	30.00%
General Motors [Member] | Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	24.00%	26.00%
Ford [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	18.00%	22.00%	38.00%
Ford [Member] | Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	11.00%	20.00%
Volkswagen [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	12.00%	9.00%	1.00%
Volkswagen [Member] | Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	8.00%
Toyota [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	8.00%	9.00%	14.00%
Toyota [Member] | Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	6.00%	4.00%

Inventories - Summary of Invent

Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Raw materials	$ 49,571	$ 59,353
Work in process	42,886	48,803
Finished goods	83,121	65,843
Inventories, net	$ 175,578	$ 173,999

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Inventory, non-current	$ 8.9	$ 8.1

Property, Plant and Equipment -

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 990,364	$ 928,038
Accumulated depreciation	(457,597)	(391,352)
Property, plant and equipment, net	532,767	536,686
Land and Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	140,471	136,918
Production Machinery and Technical Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	769,451	720,175
Leasehold Improvements and Others [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	12,883	12,192
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 67,559	$ 58,753

Property, Plant and Equipment_2

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 68.8	$ 54.2	$ 34.3

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Summary of Finite-Lived and Indefinite-Lived Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets, Gross Carrying Amount	$ 191,000	$ 191,000
Gross Carrying Amount	205,000	205,000
Accumulated Amortization	(41,411)	(15,168)
Finite-lived Intangible Assets, Currency Translation	4,454	12,554
Currency Translation	4,780	13,641
Finite-lived Intangible Assets, Net	154,043	188,386
Net	168,369	203,473
Indefinite-lived Intangible Assets, Gross Carrying Amount	14,000	14,000
Indefinite-lived Intangible Assets, Currency Translation	326	1,087
Indefinite-lived Intangible Assets, Net	14,326	15,087
Beginning Balance	304,805	286,249
Currency Translation	(13,371)	18,556
Ending Balance	291,434	304,805
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets, Gross Carrying Amount	9,000	9,000
Accumulated Amortization	(2,979)	(1,091)
Finite-lived Intangible Assets, Currency Translation	237	581
Finite-lived Intangible Assets, Net	6,258	8,490
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets, Gross Carrying Amount	15,000	15,000
Accumulated Amortization	(4,964)	(1,818)
Finite-lived Intangible Assets, Currency Translation	394	968
Finite-lived Intangible Assets, Net	10,430	14,150
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets, Gross Carrying Amount	167,000	167,000
Accumulated Amortization	(33,468)	(12,259)
Finite-lived Intangible Assets, Currency Translation	3,823	11,005
Finite-lived Intangible Assets, Net	$ 137,355	$ 165,746
Minimum [Member] | Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	4 years	5 years
Minimum [Member] | Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	3 years	4 years
Minimum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	5 years	6 years
Maximum [Member] | Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	5 years	6 years
Maximum [Member] | Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	5 years	6 years
Maximum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Remaining Weighted Average Amortization Period	10 years	11 years

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 26.3	$ 15.2
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,019	25
2,020	25
2,021	25
2,022	22.2
2,023	$ 20.2

Debt - Summary of Long-Term Deb

Debt - Summary of Long-Term Debt and Related Weighted Average Interest Rates (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total Debt	$ 684,922	$ 707,864
Debt Issuance Costs	(20,444)	(24,312)
Total Debt, Net	664,478	683,552
Less: Current portion	(3,052)	(4,000)
Long-term debt	661,426	679,552
Term Loan Facility [Member]
Debt Instrument [Line Items]
Total Debt	382,800	386,800
Debt Issuance Costs	(13,078)	(15,802)
Total Debt, Net	$ 369,722	$ 370,998
Weighted Average Interest Rate	6.30%	5.60%
Senior Notes [Member] | Senior Notes, 6.00%, due 2025 [Member]
Debt Instrument [Line Items]
Total Debt	$ 286,100	$ 300,250
Debt Issuance Costs	(7,366)	(8,510)
Total Debt, Net	$ 278,734	$ 291,740
Weighted Average Interest Rate	6.00%	6.00%
Other [Member]
Debt Instrument [Line Items]
Total Debt	$ 16,022	$ 20,814
Total Debt, Net	$ 16,022	$ 20,814
Weighted Average Interest Rate	2.20%	1.00%

Debt - Summary of Long-Term D_2

Debt - Summary of Long-Term Debt and Related Weighted Average Interest Rates (Parenthetical) (Detail)	Dec. 31, 2018	Dec. 31, 2017	Jun. 15, 2017
Senior Notes, 6.00%, due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate stated, percentage	6.00%	6.00%	6.00%

Debt - Additional Information (

Debt - Additional Information (Detail)	Jun. 29, 2018	Sep. 30, 2017	Jun. 15, 2017EUR (€)	Mar. 22, 2017USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2018EUR (€)	Dec. 31, 2017USD ($)	May 30, 2017USD ($)
Debt Instrument [Line Items]
Debt default, holder percent to declare all notes due, minimum					30.00%	30.00%
Term loan facility balance					$ 684,922,000		$ 707,864,000
Long-term debt					664,478,000		683,552,000
Long-term debt, current					3,052,000		$ 4,000,000
European Operations [Member]
Debt Instrument [Line Items]
Long-term debt								$ 70,700,000
Long-term debt, current					$ 3,100,000
Senior Notes, 6.00%, due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | €			€ 250,000,000
Debt instrument, interest rate stated, percentage			6.00%		6.00%	6.00%	6.00%
Term loan facility balance					$ 286,100,000		$ 300,250,000
Long-term debt					278,734,000		$ 291,740,000
Senior Secured Term Loan Facility [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Amount of term loan facility				$ 400,000,000
Line of credit facility maturity date				May 22, 2022
Repayments under term loan facility					17,200,000
Term loan facility balance					382,800,000
Amount outstanding					3,400,000
Amount of availability					$ 156,600,000
Senior Secured Term Loan Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Senior Secured Term Loan Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	4.00%
Senior Secured Term Loan Facility [Member] | Base Rate [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Senior Secured Term Loan Facility [Member] | Federal Funds Effective Swap Rate [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Senior Secured Term Loan Facility [Member] | One Month London Interbank Offered Rate (LIBOR) [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Senior Secured Term Loan Facility [Member] | One Month LIBOR Plus Margin [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.50%
Debt Instrument Redemption Period One [Member] | Senior Notes, 6.00%, due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Redemption percentage			103.00%
Debt Instrument Redemption Period Two [Member] | Senior Notes, 6.00%, due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Redemption percentage			101.50%		40.00%
Debt Instrument Redemption Period Three [Member] | Senior Notes, 6.00%, due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Redemption percentage			100.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Commitment fees percentage				0.50%
Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Commitment fees percentage		0.50%
Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Commitment fees percentage		0.25%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		3.50%		1.00%
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		3.00%		3.50%
Revolving Credit Facility [Member] | Base Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.50%
Revolving Credit Facility [Member] | Base Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.00%
Revolving Credit Facility [Member] | Federal Funds Effective Swap Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.50%
Revolving Credit Facility [Member] | One Month London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Revolving Credit Facility [Member] | One Month London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.50%
Revolving Credit Facility [Member] | Senior Secured Term Loan Facility [Member]
Debt Instrument [Line Items]
Amount of term loan facility				$ 160,000,000
Line of credit facility maturity date				May 23, 2024
Outstanding borrowings					$ 0
Term Loan Facility [Member] | Senior Secured Term Loan Facility [Member]
Debt Instrument [Line Items]
Percentage of capital stock issued					65.00%	65.00%
Equipment Loan [Member] | European Operations [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate stated, percentage					2.20%	2.20%
Long-term debt					$ 16,000,000
Line of Credit [Member] | European Operations [Member]
Debt Instrument [Line Items]
Debt instrument expiry date					Jul. 31, 2020
Available unused line of credit | €						€ 30,000,000
Line of Credit [Member] | Euribor [Member] | Minimum [Member] | European Operations [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.95%

Redeemable Preferred Stock - Ad

Redeemable Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Nov. 07, 2018	Aug. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
Temporary Equity [Line Items]
Temporary equity, stock issued during period, shares, new issues			150,000	150,000
Temporary equity, par value			$ 0.01	$ 0.01
Proceeds from issuance of redeemable preferred shares				$ 150,000
Convertible Preferred Stock, Redemption Value			$ 300,000
Issuance costs				3,737
Proceeds from issuance of redeemable preferred shares, net of issuance costs				146,300
Embedded derivative liability			$ 3,134	4,685
Adjusted proceeds from issuance of redeemable preferred shares				135,500
Redemption period			8 years
Carrying value of redeemable preferred stock	$ 17,200		$ (17,200)
Preferred stock redemption extended date	Sep. 14, 2025
Accumulated accretion value			9,000
Redeemable preferred stock			144,463	$ 144,694
Convertible Preferred Stock Redemption Period Two [Member]
Temporary Equity [Line Items]
Convertible Preferred Stock, Redemption Value			$ 300,000
Convertible preferred stock, redemption value percent of stated value			200.00%
Convertible preferred stock, total shares issued upon conversion			5,300,000
Series A Redeemable Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity, stock issued during period, shares, new issues				140,202
Temporary equity, par value		$ 0.01
Temporary equity, liquidation preference per share		1,000
Temporary equity, conversion price		$ 28.162
Preferred stock, dividend rate, percentage		9.00%
Convertible preferred stock, threshold stock price trigger				$ 84.49
Series B Redeemable Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity, stock issued during period, shares, new issues				9,798

European Non-Controlling Rede_3

European Non-Controlling Redeemable Equity - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Redeemable Noncontrolling Interest [Line Items]
Accrued annual dividend to non-controlling interest	$ 1,512
Redemption premium	1,000
Domination and Profit Loss Transfer Agreement [Member]
Redeemable Noncontrolling Interest [Line Items]
Non-controlling interests with carrying value reclassified from stockholders' equity to mezzanine equity	$ 51,900

European Non-Controlling Rede_4

European Non-Controlling Redeemable Equity - Summary of Redeemable Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018
Redeemable Noncontrolling Interest [Line Items]
Dividends accrued		$ (1,512)
Translation adjustment	$ 2,900
Redeemable Noncontrolling Interest [Member]
Redeemable Noncontrolling Interest [Line Items]
Reclassification of non-controlling interests		51,943
Redemption value adjustment		3,625
Dividends accrued		1,512
Dividends paid		(964)
Translation adjustment		(3,219)
Purchase of shares		(39,048)
Ending Balance	$ 13,849	$ 13,849

Earning Per Share - Additional

Earning Per Share - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Nov. 07, 2018
Earnings Per Share [Abstract]
Reduction in carrying value of redeemable preferred stock	$ (17.2)	$ 17.2
Net increase in embedded derivative liability	$ 1.9

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Earnings Per share, Basic and Diluted (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Basic Earnings Per Share:
Reported net income (loss) attributable to Superior					$ (4,648)	$ 2,615	$ (7,272)	$ 3,102	$ 25,961	$ (6,203)	$ 41,381
Less: Redeemable preferred stock dividends and accretion									(32,462)	(18,912)
Add: Preferred stock modification									15,257
Less: European non-controlling redeemable equity dividend									(1,512)
Basic numerator									$ 7,244	$ (25,115)	$ 41,381
Basic earnings (loss) per share	$ 0.61	$ (0.37)	$ (0.02)	$ 0.07	$ (0.50)	$ (0.22)	$ (0.41)	$ 0.12	$ 0.29	$ (1.01)	$ 1.63
Weighted average shares outstanding-Basic									24,994	24,929	25,439
Diluted Earnings Per Share:
Reported net income (loss) attributable to Superior					$ (4,648)	$ 2,615	$ (7,272)	$ 3,102	$ 25,961	$ (6,203)	$ 41,381
Less: Redeemable preferred stock dividends and accretion									(32,462)	(18,912)
Add: Preferred stock modification									15,257
Less: European non-controlling redeemable equity dividend									(1,512)
Diluted numerator									$ 7,244	$ (25,115)	$ 41,381
Diluted earnings (loss) per share	$ 0.61	$ (0.37)	$ (0.02)	$ 0.07	$ (0.50)	$ (0.22)	$ (0.41)	$ 0.12	$ 0.29	$ (1.01)	$ 1.62
Weighted average shares outstanding-Basic									24,994	24,929	25,439
Dilutive effect of common share equivalents									161		100
Weighted average shares outstanding-Diluted									25,155	24,929	25,539

Income Taxes - Income Before In

Income Taxes - Income Before Income Taxes From Domestic and International Jurisdictions (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Income Tax Disclosure [Abstract]
Domestic									$ (44,058)	$ (63,716)	$ 18,499
Foreign									76,310	64,582	36,222
Consolidated income (loss) before income taxes	$ 13,349	$ (7,714)	$ 12,930	$ 13,687	$ 7,308	$ (501)	$ (9,241)	$ 3,300	$ 32,252	$ 866	$ 54,721

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Income Tax Disclosure [Abstract]
Federal									$ 3,714	$ 6,121	$ (5,017)
State									127	(390)	450
Foreign									(11,180)	(12,564)	(10,639)
Total current taxes									(7,339)	(6,833)	(15,206)
Federal									(919)	(4,387)	(1,199)
State									521	1,492	(332)
Foreign									1,446	2,853	3,397
Total deferred taxes									1,048	(42)	1,866
Income tax provision	$ (5,177)	$ 7,051	$ (4,795)	$ (3,370)	$ (11,754)	$ 3,355	$ 1,722	$ (198)	$ (6,291)	$ (6,875)	$ (13,340)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of the U.S. Federal Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Income Tax Disclosure [Abstract]
Statutory rate	(21.00%)	(35.00%)	(35.00%)
State tax provisions, net of federal income tax benefit	6.40%	263.40%	(6.30%)
Tax credits	1.30%	88.90%	0.60%
Foreign income taxes at rates other than the statutory rate	16.80%	1206.60%	11.70%
Valuation allowance and other	(28.00%)	(138.00%)	5.10%
Changes in tax liabilities, net	(0.60%)	(11.30%)	0.50%
Share based compensation	(1.00%)	(61.50%)	(1.20%)
Transaction costs		(372.20%)
US Tax Reform implementation	10.90%	(1918.70%)
US Tax on non-US income	(16.10%)
Non-taxable income	16.30%	152.60%
Other	(4.50%)	31.30%	0.20%
Effective income tax rate	(19.50%)	(793.90%)	(24.40%)

Income Taxes - Summary of Defer

Income Taxes - Summary of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Accrued liabilities	$ 8,117	$ 2,445
Hedging and foreign currency losses	(1,163)	2,034
Deferred compensation	8,021	8,628
Inventory reserves	3,984	2,954
Net loss carryforwards and credits	51,552	69,018
Interest carryforwards	11,269
Competent authority deferred tax assets and other foreign timing differences	6,749	6,939
Other	(3,921)	(830)
Total before valuation allowance	84,608	91,188
Valuation allowance	(16,576)	(7,634)
Net deferred income tax assets	68,032	83,554
Deferred income tax liabilities:
Intangibles, property, plant and equipment and other	(44,591)	(57,791)
Deferred income tax liabilities	(44,591)	(57,791)
Net deferred income tax assets	23,441	25,763
Long-term deferred income tax assets	42,105	54,302
Long-term deferred income tax liabilities	(18,664)	(28,539)
Net deferred tax asset	$ 23,441	$ 25,763

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Unrecognized Tax Benefits Summary [Line Items]
Valuation allowance	$ 9
Statutory rate	21.00%	35.00%	35.00%
Adjustments provision on re-measurement of deferred tax assets	$ (3.9)
Operating Loss Carryforwards	12.9
Tax credit carryforward, amount	38.6
Unremitted earnings of foreign subsidiaries	173
Unrecognized tax benefits that would favorably impact effective tax rate	2.2
Unrecognized tax benefits, income tax penalties and interest accrued	3.3	$ 2.4	$ 1.8
GILTI [Member]
Unrecognized Tax Benefits Summary [Line Items]
Favorable measurement adjustment to transition tax obligation	$ 5.2
Earliest Tax Year [Member]
Unrecognized Tax Benefits Summary [Line Items]
Operating loss carryforwards, expiration year	2,019
State tax credit carryforwards, expiration year	2,021
Open tax year	2,013
Latest Tax Year [Member]
Unrecognized Tax Benefits Summary [Line Items]
Operating loss carryforwards, expiration year	2,038
State tax credit carryforwards, expiration year	2,026
Open tax year	2,018

Income Taxes - Schedule of Unre

Income Taxes - Schedule of Unrecognized Tax Benefits Roll Forward (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Income Tax Disclosure [Abstract]
Beginning balance	$ 33,054	$ 3,446	$ 7,318
Increases (decreases) due to foreign currency translations	(2,018)
Increases (decreases) as a result of positions taken during: Prior periods			(3,872)
Current period		29,773
Expiration of applicable statutes of limitation		(165)
Ending balance	$ 31,036	$ 33,054	$ 3,446

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Leases [Abstract]
Operating leases, rent expense, net	$ 7	$ 4.3	$ 1.9

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Rental Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,019	$ 4,249
2,020	3,232
2,021	2,870
2,022	2,635
2,023	2,346
Thereafter	7,647
Future minimum lease payments	$ 22,979

Related Parties - Additional In

Related Parties - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Related Party Transactions [Abstract]
Related party transaction, amounts of transaction	$ 479,520	$ 376,920	$ 243,000

Retirement Plans - Additional I

Retirement Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)Age	Dec. 31, 2017USD ($)	Dec. 25, 2016USD ($)
Retirement Benefits [Abstract]
Cash surrender value	$ 8.1	$ 8
Age for benefits | Age	65
Defined contribution plan, cost recognized	$ 1.8	$ 1.7	$ 1.4

Retirement Plans - Summary of C

Retirement Plans - Summary of Changes in Plan Assets and Plan Benefit Obligations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Retirement Benefits [Abstract]
Beginning benefit obligation	$ 29,759	$ 27,612
Interest cost	1,086	1,189	$ 1,216
Actuarial (gain) loss	(2,486)	2,300
Benefit payments	(1,406)	(1,342)
Ending benefit obligation	$ 26,953	$ 29,759	$ 27,612

Retirement Plans - Schedule of

Retirement Plans - Schedule of Defined Benefit Plans Disclosures (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Fair value of plan assets at beginning of year	$ 0	$ 0
Employer contribution	1,406	1,342
Benefit payments	(1,406)	(1,342)
Fair value of plan assets at end of year	0	0
Funded status	(26,953)	(29,759)
Accrued expenses	(1,392)	(1,407)
Other non-current liabilities	(25,561)	(28,352)
Net amount recognized	(26,953)	(29,759)
Net actuarial loss	4,799	7,722
Prior service cost	(1)	(1)
Net amount recognized, before tax effect	$ 4,798	$ 7,721
Discount rate	4.40%	3.70%
Rate of compensation increase	3.00%	3.00%

Retirement Plans - Schedule o_2

Retirement Plans - Schedule of Net Benefit Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Retirement Benefits [Abstract]
Interest cost	$ 1,086	$ 1,189	$ 1,216
Amortization of actuarial loss	438	369	335
Net periodic pension cost	$ 1,524	$ 1,558	$ 1,551
Discount rate	3.70%	4.40%	4.40%
Rate of compensation increase	3.00%	3.00%	3.00%

Retirement Plans - Schedule o_3

Retirement Plans - Schedule of Expected Benefit Payments (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Retirement Benefits [Abstract]
2,019	$ 1,422
2,020	1,484
2,021	1,457
2,022	1,495
2,023	1,472
Years 2024 to 2028	$ 8,448

Retirement Plans - Periodic Pen

Retirement Plans - Periodic Pension Cost, Next Fiscal Year (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Defined Benefit Plan Disclosure [Line Items]
Interest cost		$ 1,086	$ 1,189	$ 1,216
Net periodic pension cost		$ 1,524	$ 1,558	$ 1,551
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,144
Amortization of actuarial loss	209
Net periodic pension cost	$ 1,353

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Payroll and related benefits	$ 23,503	$ 27,954
Insurance Reserves	1,120	590
Taxes, other than income taxes	8,115	9,419
Current portion of derivative liability	2,506	6,595
Dividends and interest	4,197	7,322
Deferred tooling revenue	5,810	4,654
Current portion of executive retirement liabilities	1,392	1,407
Professional Fees	4,750	3,674
Warranty Liability	437	872
Other	13,832	6,299
Accrued liabilities	$ 65,662	$ 68,786

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorizes issuance of common stock	4,350,000
Number of shares available for grant	2,400,000
Maximum shares that may be used as full value awards	1,200,000
Stock-Based Cpmpensation Expense	$ 2.1	$ 1.6	$ 2.3
Amount of unrecognized stock-based compensation expense	$ 2.4
Weighted average period for recognition	1 year 6 months
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Shares Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Restricted Performance Stock Unit and Equity Incentive Activity (Detail)	12 Months Ended
	Dec. 31, 2018$ / sharesshares
Number of Options Outstanding
Number of Options Outstanding, Beginning balance (in shares)	145,625
Granted (in shares)	0
Settled (in shares)	(4,500)
Forfeited or expired (in shares)	(82,125)
Number of Options Outstanding, Ending balance (in shares)	59,000
Options vested or expected to vest, Outstanding (in shares)	59,000
Weighted Average Exercise Price
Weighted Average Exercise Price, Beginning balance (in dollars per share) | $ / shares	$ 18.96
Granted (in dollars per share) | $ / shares	0
Settled (in dollars per share) | $ / shares	15.17
Forfeited or expired (in dollars per share) | $ / shares	19.62
Weighted Average Exercise Price, Ending balance (in dollars per share) | $ / shares	$ 18.33
Restricted Stock Units [Member]
Number of Awards
Number of Awards, Beginning balance (in shares)	169,266
Granted (in shares)	204,003
Settled (in shares)	(66,138)
Forfeited or expired (in shares)	(123,405)
Number of Awards, Ending balance (in shares)	183,726
Number of Awards, vested or expected to vest, Outstanding (in shares)	183,726
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance (in dollars per share) | $ / shares	$ 22.27
Granted (in dollars per share) | $ / shares	15.91
Settled (in dollars per share) | $ / shares	22.67
Forfeited or expired (in dollars per share) | $ / shares	18.98
Weighted Average Grant Date Fair Value, Ending balance (in dollars per share) | $ / shares	$ 17.26
Performance Shares Unit [Member]
Number of Awards
Number of Awards, Beginning balance (in shares)	239,674
Granted (in shares)	325,526
Forfeited or expired (in shares)	(268,677)
Number of Awards, Ending balance (in shares)	296,523
Number of Awards, vested or expected to vest, Outstanding (in shares)	111,071
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Beginning balance (in dollars per share) | $ / shares	$ 22.58
Granted (in dollars per share) | $ / shares	17.12
Forfeited or expired (in dollars per share) | $ / shares	19.8
Weighted Average Grant Date Fair Value, Ending balance (in dollars per share) | $ / shares	$ 19.1

Common Stock Repurchase Progr_2

Common Stock Repurchase Programs - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased			$ 5,014,000	$ 20,719,000
2016 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Amount authorized to be repurchased	$ 50,000,000
Common stock repurchased	15,400,000
Remaining Amount authorized to be repurchased	$ 34,600,000
Stock repurchased during period, shares		0

Receivables Factoring - Additio

Receivables Factoring - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018USD ($)
Accounts Receivable [Line Items]
Trade receivables	$ 276,800,000
Collective limit under factoring arrangements	80,900,000
Factored receivables yet not collected	53,800,000
Other Nonoperating (Expense) Income [Member]
Accounts Receivable [Line Items]
Factoring fees	$ 900,000

Quarterly Financial Data - Sche

Quarterly Financial Data - Schedule of Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Quarterly Financial Information Disclosure [Abstract]
NET SALES	$ 378,823	$ 347,612	$ 388,944	$ 386,448	$ 361,803	$ 331,404	$ 240,628	$ 174,220	$ 1,501,827	$ 1,108,055	$ 732,677
Gross profit	36,304	23,673	53,559	49,991	39,695	23,893	20,105	19,204	163,527	102,897	86,204
Income (loss) from operations	19,213	7,688	31,270	27,634	13,814	5,758	(1,998)	3,944	85,805	21,518	54,602
Consolidated income (loss) before income taxes	13,349	(7,714)	12,930	13,687	7,308	(501)	(9,241)	3,300	32,252	866	54,721
Income tax (provision) benefit	(5,177)	7,051	(4,795)	(3,370)	(11,754)	3,355	1,722	(198)	(6,291)	(6,875)	(13,340)
Consolidated net income (loss)	$ 8,172	$ (663)	$ 8,135	$ 10,317	(4,446)	2,854	(7,519)	3,102	25,961	(6,009)	41,381
Less: Net loss (income) attributable to non-controlling interest					(202)	(239)	247			(194)
Net income (loss) attributable to Superior					$ (4,648)	$ 2,615	$ (7,272)	$ 3,102	$ 25,961	$ (6,203)	$ 41,381
Basic	$ 0.61	$ (0.37)	$ (0.02)	$ 0.07	$ (0.50)	$ (0.22)	$ (0.41)	$ 0.12	$ 0.29	$ (1.01)	$ 1.63
Diluted	0.61	(0.37)	(0.02)	0.07	(0.50)	(0.22)	(0.41)	0.12	0.29	(1.01)	1.62
Dividends declared per share	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.18	$ 0.36	$ 0.45	$ 0.72
Other comprehensive income (loss), net of tax	$ (20,057)	$ 21,960	$ (53,178)	$ 34,901					$ (16,374)

Quarterly Financial Data - Sc_2

Quarterly Financial Data - Schedule of Quarterly Financial Information (Parenthetical) (Detail) $ in Millions	3 Months Ended
	Dec. 31, 2018USD ($)
Quarterly Financial Information Disclosure [Abstract]
Reclassification of non-controlling redeemable equity translation adjustments	$ 2.9

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 25, 2016
Allowance for Doubtful Accounts Receivable [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 2,325	$ 919	$ 867
Additions, Charge to Costs and Expenses	2,311	1,127	403
Additions, Other		1,162
Deductions From Reserves	(338)	(883)	(351)
Balance at End of Year	4,298	2,325	919
Valuation Allowances for Deferred Tax Assets [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	7,634	3,123	5,891
Additions, Charge to Costs and Expenses	9,036	1,005	698
Additions, Other		3,506
Deductions From Reserves	(94)		(3,466)
Balance at End of Year	$ 16,576	$ 7,634	$ 3,123