SunCoke Energy (SXC) 10-K 25 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 19, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-35243
Entity Registrant Name	SUNCOKE ENERGY, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	90-0640593
Entity Address, Address Line One	1011 Warrenville Road
Entity Address, Address Line Two	Suite 600
Entity Address, City or Town	Lisle
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60532
City Area Code	630
Local Phone Number	824-1000
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	SXC
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 243,652,539
Entity Common Stock, Shares Outstanding (in shares)		82,806,106
Documents Incorporated by Reference	Portions of the SunCoke Energy, Inc. 2021 definitive Proxy Statement, which will be filed with the Securities and Exchange Commission within 120 days after December 31, 2020, are incorporated by reference in Part III of this Form 10-K.
Entity Central Index Key	0001514705
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues
Sales and other operating revenue	$ 1,333	$ 1,600.3	$ 1,450.9
Costs and operating expenses
Cost of products sold and operating expenses	1,048.2	1,277.6	1,124.5
Selling, general and administrative expenses	81.4	75.8	66.1
Depreciation and amortization expense	133.7	143.8	141.6
Long-lived asset and goodwill impairment	0	247.4	0
Total costs and operating expenses	1,263.3	1,744.6	1,332.2
Operating income (loss)	69.7	(144.3)	118.7
Interest expense, net	56.3	60.3	61.4
(Gain) loss on extinguishment of debt, net	(5.7)	(1.5)	0.3
Income (loss) before income tax expense (benefit) and loss from equity method investment	19.1	(203.1)	57
Income tax expense (benefit)	10.3	(54.7)	4.6
Loss from equity method investment	0	0	5.4
Net income (loss)	8.8	(148.4)	47
Less: Net income attributable to noncontrolling interests	5.1	3.9	20.8
Net income (loss) attributable to SunCoke Energy, Inc.	$ 3.7	$ (152.3)	$ 26.2
Earnings (loss) attributable to SunCoke Energy, Inc. per common share:
Basic (in dollars per share)	$ 0.04	$ (1.98)	$ 0.40
Diluted (in dollars per share)	$ 0.04	$ (1.98)	$ 0.40
Weighted average number of common shares outstanding:
Basic (in shares)	83	76.8	64.7
Diluted (in shares)	83.2	76.8	65.5

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 8.8	$ (148.4)	$ 47
Other comprehensive income (loss):
Reclassifications of actuarial loss amortization and prior service benefit to earnings (net of related tax expense of zero for all years)	0.1	0	(0.1)
Retirement benefit plans funded status adjustment (net of related tax benefit (expense) of $0.4 million, $0.3 million and $(0.2) million, respectively)	(1.6)	(0.7)	0.6
Currency translation adjustment	(1.2)	(0.6)	(1.4)
Recognition of accumulated currency translation loss upon sale of equity method investment	0	0	9
Comprehensive income (loss)	6.1	(149.7)	55.1
Less: Comprehensive income attributable to noncontrolling interests	5.1	3.9	20.8
Comprehensive income (loss) attributable to SunCoke Energy, Inc.	$ 1	$ (153.6)	$ 34.3

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net of related tax benefit, reclassifications of prior service benefit and actuarial loss amortization to earnings	$ 0	$ 0	$ 0
Retirement expense (benefit) plans funded status adjustment, tax	$ 400,000	$ 300,000	$ (200,000)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 48.4	$ 97.1
Receivables, net	46.3	59.5
Inventories	126.6	147
Income tax receivable	5.5	2.2
Other current assets	2.9	2.5
Total current assets	229.7	308.3
Properties, plants and equipment (net of accumulated depreciation of $1,032.9 and $903.7 at December 31, 2020 and 2019, respectively)	1,328	1,390.2
Goodwill and other intangible assets, net	37.2	38.1
Deferred charges and other assets	18.5	17.2
Total assets	1,613.4	1,753.8
Liabilities and Equity
Accounts payable	104.1	142.4
Accrued liabilities	49.8	47.3
Current portion of financing obligations	3	2.9
Interest payable	2	2.2
Total current liabilities	158.9	194.8
Long-term debt and financing obligations	673.9	780
Accrual for black lung benefits	60	50.5
Retirement benefit liabilities	24.7	24.5
Deferred income taxes	159.3	147.6
Asset retirement obligations	11.4	14.4
Other deferred credits and liabilities	24.3	23.6
Total liabilities	1,112.5	1,235.4
Equity
Preferred stock, $0.01 par value. Authorized 50,000,000 shares; no issued shares at both December 31, 2020 and 2019	0	0
Common stock, $0.01 par value. Authorized 300,000,000 shares; issued 98,177,941 and 98,047,389 shares at December 31, 2020 and 2019, respectively	1	1
Treasury stock, 15,404,482 and 13,783,182 shares at December 31, 2020 and 2019, respectively	(184)	(177)
Additional paid-in capital	715.7	712.1
Accumulated other comprehensive loss	(17.1)	(14.4)
Retained deficit	(46.6)	(30.1)
Total SunCoke Energy, Inc. stockholders' equity	469	491.6
Noncontrolling interests	31.9	26.8
Total equity	500.9	518.4
Total liabilities and equity	$ 1,613.4	$ 1,753.8

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accumulated depreciation	$ 1,032.9	$ 903.7
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares, issued (in shares)	98,177,941	98,047,389
Treasury stock, shares (in shares)	15,404,482	13,783,182

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows from Operating Activities:
Net income (loss)	$ 8.8	$ (148.4)	$ 47
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Long-lived asset and goodwill impairment	0	247.4	0
Depreciation and amortization expense	133.7	143.8	141.6
Deferred income tax expense (benefit)	12.1	(63.1)	(3.4)
Payments in excess of expense for postretirement plan benefits	(1.7)	(1.9)	(2.4)
Share-based compensation expense	3.8	4.5	3.1
(Gain) loss on extinguishment of debt, net	(5.7)	(1.5)	0.3
Loss from equity method investment	0	0	5.4
Changes in working capital pertaining to operating activities:
Receivables, net	13.2	15.9	(6.9)
Inventories	21.8	(36.6)	0.6
Accounts payable	(38)	23.5	(0.7)
Accrued liabilities	2.5	(2.4)	(6)
Interest payable	(0.2)	(1.4)	(1.8)
Income taxes	(3.3)	(1.5)	4.5
Other	10.8	3.6	4.5
Net cash provided by operating activities	157.8	181.9	185.8
Cash Flows from Investing Activities:
Capital expenditures	(73.9)	(110.1)	(100.3)
Sale of equity method investment	0	0	4
Other investing activities	(1.4)	0.3	0.5
Net cash used in investing activities	(75.3)	(109.8)	(95.8)
Cash Flows from Financing Activities:
Proceeds from issuance of long-term debt	0	0	45
Repayment of long-term debt	(55.9)	(90.5)	(45.7)
Debt issuance costs	0	(2.1)	(0.5)
Proceeds from revolving facility	629.9	408.6	179.5
Repayment of revolving facility	(684.9)	(370.3)	(204.5)
Proceeds from financing obligation	10	0	0
Repayment of financing obligations	(3)	(2.9)	(2.6)
Dividends paid	(19.9)	(5.1)	0
Shares repurchased	(7)	(36.3)	0
Acquisition of additional interest in the Partnership	0	0	(4.2)
Cash distributions to noncontrolling interests	0	(14.2)	(31.9)
Other financing activities	(0.4)	(7.9)	0.4
Net cash used in financing activities	(131.2)	(120.7)	(64.5)
Net (decrease) increase in cash and cash equivalents	(48.7)	(48.6)	25.5
Cash and cash equivalents at beginning of year	97.1	145.7	120.2
Cash and cash equivalents at end of year	48.4	97.1	145.7
Supplemental Disclosure of Cash Flow Information
Interest paid, net of capitalized interest of $0.2 million, $2.3 million and $3.2 million, respectively	51.8	58.2	59.6
Income taxes paid, net of refunds of $3.0 million, $0.3 million and $4.3 million, respectively	$ 1.1	$ 9.5	$ 3.7

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Cash Flows [Abstract]
Capitalized interest	$ 0.2	$ 2.3	$ 3.2
Tax refunds	$ 3	$ 0.3	$ 4.3

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Retained Earnings (Deficit)	Total SunCoke Energy, Inc. Equity	Non- controlling Interests
Beginning balance, (in shares) at Dec. 31, 2017		72,006,905	7,477,657
Beginning balance at Dec. 31, 2017	$ 659.6	$ 0.7	$ (140.7)	$ 486.2	$ (21.2)	$ 101.2	$ 426.2	$ 233.4
Stockholders' Equity
Net income (loss)	47					26.2	26.2	20.8
Reclassification of prior service cost and actuarial loss amortization to earnings, net of tax	(0.1)				(0.1)		(0.1)
Retirement benefit plans funded status adjustment	0.6				0.6		0.6
Currency translation adjustment	(1.4)				(1.4)		(1.4)
Recognition of accumulated currency translation loss upon sale of equity method investment	9				9		9	0
Cash distribution to noncontrolling interests	(31.9)							(31.9)
Share-based compensation expense	3.1			3.1			3.1	0
Share-issuances, net of shares withheld for taxes, (in shares)		226,845
Share-issuances, net of shares withheld for taxes	0.7			0.7			0.7
Acquisition of additional interest in the Partnership:
Cash paid	(4.2)			(1.5)			(1.5)	(2.7)
Deferred tax adjustment	0.3			0.3			0.3
Ending balance. (in shares) at Dec. 31, 2018		72,233,750	7,477,657
Ending balance at Dec. 31, 2018	682.7	$ 0.7	$ (140.7)	488.8	(13.1)	127.4	463.1	219.6
Stockholders' Equity
Net income (loss)	(148.4)					(152.3)	(152.3)	3.9
Retirement benefit plans funded status adjustment	(0.7)				(0.7)		(0.7)
Currency translation adjustment	(0.6)				(0.6)		(0.6)
Recognition of accumulated currency translation loss upon sale of equity method investment	0
Cash distribution to noncontrolling interests	(14.2)							(14.2)
Share-based compensation expense	4.5			4.5			4.5	0
Share-issuances, net of shares withheld for taxes, (in shares)		359,988
Share-issuances, net of shares withheld for taxes	(1.7)			(1.7)			(1.7)
Share repurchases, (in shares)			6,305,525
Share repurchases	(36.3)		$ (36.3)				(36.3)
Dividends	(5.2)					(5.2)	(5.2)
Acquisition of additional interest in the Partnership:
Share issuance, for the acquisition of Partnership public units (in shares)		24,818,149
Share issuances, for the acquisition of Partnership public units	0	$ 0.3		182.2			182.5	(182.5)
Share issuances, for the final Partnership distribution (in shares)		635,502
Transaction costs	(5.4)			(5.4)			(5.4)
Deferred tax adjustment	43.7			43.7			43.7
Ending balance. (in shares) at Dec. 31, 2019		98,047,389	13,783,182
Ending balance at Dec. 31, 2019	518.4	$ 1	$ (177)	712.1	(14.4)	(30.1)	491.6	26.8
Stockholders' Equity
Net income (loss)	8.8					3.7	3.7	5.1
Reclassification of prior service cost and actuarial loss amortization to earnings, net of tax	0.1				0.1		0.1
Retirement benefit plans funded status adjustment	(1.6)				(1.6)		(1.6)
Currency translation adjustment	(1.2)				(1.2)		(1.2)
Recognition of accumulated currency translation loss upon sale of equity method investment	0
Share-based compensation expense	3.8			3.8			3.8	0
Share-issuances, net of shares withheld for taxes, (in shares)		130,552
Share-issuances, net of shares withheld for taxes	(0.2)			(0.2)			(0.2)
Share repurchases, (in shares)			1,621,300
Share repurchases	(7)		$ (7)				(7)
Dividends	(20.2)					(20.2)	(20.2)
Ending balance. (in shares) at Dec. 31, 2020		98,177,941	15,404,482
Ending balance at Dec. 31, 2020	$ 500.9	$ 1	$ (184)	$ 715.7	$ (17.1)	$ (46.6)	$ 469	$ 31.9

Consolidated Statements of Eq_2

Consolidated Statements of Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Retirement expense (benefit) plans funded status adjustment, tax	$ 0.4	$ 0.3	$ (0.2)

General and Basis of Presentati

General and Basis of Presentation	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General and Basis of Presentation	1. General and Basis of Presentation Description of Business SunCoke Energy, Inc. (“SunCoke Energy,” “SunCoke,” “Company,” “we,” “our” and “us”) is the largest independent producer of high-quality coke in the Americas, as measured by tons of coke produced each year, and has more than 60 years of coke production experience. Coke is a principal raw material in the blast furnace steelmaking process and is produced by heating metallurgical coal in a refractory oven, which releases certain volatile components from the coal, thus transforming the coal into coke. Additionally, we own and operate a logistics business, which primarily provides handling and/or mixing services of coal and other aggregates to third-party customers as well as to our own cokemaking facilities. We have designed, developed, built, own and operate five cokemaking facilities in the United States (“U.S.”) with collective nameplate capacity to produce approximately 4.2 million tons of blast furnace coke per year. Additionally, we have designed and operate one cokemaking facility in Brazil under licensing and operating agreements on behalf of ArcelorMittal Brasil S.A. ("ArcelorMittal Brazil”), which has approximately 1.7 million tons of annual cokemaking capacity. To diversify our business and customer base, SunCoke began exploring the foundry coke market in 2020. Foundry coke is a high-quality grade of coke that is used at foundries to melt iron and various metals in cupola furnaces, which is further processed via casting or molding into products used in various industries such as construction, transportation and industrial products. Throughout 2020, we tested production capacity and executed successful test sales of foundry coke. We will begin to produce and sell foundry coke on a commercial scale in 2021. Our cokemaking ovens utilize efficient, modern heat recovery technology designed to combust the coal’s volatile components liberated during the cokemaking process and use the resulting heat to create steam or electricity for sale. This differs from by-product cokemaking, which repurposes the coal’s liberated volatile components for other uses. We have constructed the only greenfield cokemaking facilities in the U.S. in approximately 30 years and are the only North American coke producer that utilizes heat recovery technology in the cokemaking process. We provide steam pursuant to steam supply and purchase agreements with our customers. Electricity is sold into the regional power market or pursuant to energy sales agreements. Our logistics business provides handling and/or mixing services to steel, coke (including some of our domestic cokemaking facilities), electric utility, coal producing and other manufacturing based customers. The logistics business has terminals in Indiana, West Virginia, Virginia, and Louisiana with collective capacity to mix and/or transload more than 40 million tons of coal and other aggregates annually and has total storage capacity of approximately 3 million tons. Incorporated in Delaware in 2010 and headquartered in Lisle, Illinois, we became a publicly-traded company in 2011, and our stock is listed on the New York Stock Exchange (“NYSE”) under the symbol “SXC.” Consolidation and Basis of Presentation The consolidated financial statements of the Company and its subsidiaries were prepared in accordance with accounting principles generally accepted in the U.S. ("GAAP") and include the assets, liabilities, revenues and expenses of the Company and all subsidiaries where we have a controlling financial interest. Intercompany transactions and balances have been eliminated in consolidation. Our consolidated financial statements have historically included SunCoke Energy Partners, L.P. (the “Partnership”), which owned our Haverhill, Middletown, and Granite City cokemaking facilities and Convent Marine Terminal ("CMT"), Kanawha River Terminal ("KRT") and SunCoke Lake Terminal ("Lake Terminal"). On June 28, 2019, the Company acquired the outstanding units of the Partnership not already owned by SunCoke, at which time the Partnership became a wholly-owned subsidiary of SunCoke. See Note 3. As of January 1, 2020, the Partnership merged with and into SunCoke Energy Partners Finance Corp., which is also a wholly-owned subsidiary of the Company.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual amounts could differ from these estimates. Revenue Recognition The Company sells coke as well as steam and electricity and also provides mixing and/or handling services of coal and other aggregates. The Company also receives fees for operating the cokemaking plant in Brazil and for the licensing of its proprietary technology for use at this facility as well as reimbursement of substantially all of its operating costs. See Note 19. Cash Equivalents The Company considers all highly liquid investments with a remaining maturity of three months or less at the time of purchase to be cash equivalents. These cash equivalents consist principally of money market funds. Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method, except for the Company’s materials and supplies inventory, which are determined using the average-cost method. The Company primarily utilizes the selling prices under its long-term coke supply contracts to record lower of cost or net realizable value inventory adjustments. Properties, Plants and Equipment Plants and equipment are depreciated on a straight-line basis over their estimated useful lives. Coke and energy plant, machinery and equipment are generally depreciated over 25 to 30 years. Logistics plant and equipment are generally depreciated over 15 to 35 years. Depreciation and amortization is excluded from cost of products sold and operating expenses and is presented separately on the Consolidated Statements of Operations. Gains and losses on the disposal or retirement of fixed assets are reflected in earnings when the assets are sold or retired. Amounts incurred that extend an asset’s useful life, increase its productivity or add production capacity are capitalized. The Company accounts for changes in useful lives, when appropriate, as a change in estimate, with prospective application only. The Company capitalized interest of $0.2 million, $2.3 million, and $3.2 million in 2020, 2019 and 2018, respectively. Direct costs, such as outside labor, materials, internal payroll and benefits costs incurred during capital projects are capitalized; indirect costs are not capitalized. Normal repairs and maintenance costs are expensed as incurred. Goodwill Goodwill, which represents the excess of the purchase price over the fair value of net assets acquired, is tested for impairment as of October 1 of each year, or when events occur or circumstances change that would, more likely than not, reduce the fair value of a reporting unit to below its carrying value. The Company performs its annual goodwill impairment test by comparing the fair value of the reporting unit with its carrying amount. The Company would recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. See Note 8. Intangible Assets Intangible assets are primarily comprised of permits. Intangible assets are amortized over their useful lives in a manner that reflects the pattern in which the economic benefit of the intangible asset is consumed. Intangible assets are assessed for impairment when a triggering event occurs. Impairment of Long-Lived Assets Long-lived assets, which includes intangible assets and properties, plants and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. A long-lived asset, or group of assets, is considered to be impaired when the undiscounted net cash flows expected to be generated by the asset are less than its carrying amount. Such estimated future cash flows are highly subjective and are based on numerous assumptions about future operations and market conditions. The impairment recognized is the amount by which the carrying amount exceeds the fair market value of the impaired asset, or group of assets. It is also difficult to precisely estimate fair market value because quoted market prices for our long-lived assets may not be readily available. Therefore, fair market value is generally based on the present values of estimated future cash flows using discount rates commensurate with the risks associated with the assets being reviewed for impairment. See Note 8. Income Taxes Deferred tax asset and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those differences are projected to be recovered or settled. The Company recognizes uncertain tax positions in its financial statements when minimum recognition threshold and measurement attributes are met in accordance with current accounting guidance. See Note 5. Black Lung Benefit Liabilities The Company has obligations related to coal workers’ pneumoconiosis, or black lung, benefits of certain of our former coal miners and their dependents. We adjust our liability each year based upon actuarial calculations of our expected future payments for these benefits, including a provision for incurred but not reported losses. See Note 13. Postretirement Benefit Plan Liabilities The postretirement benefit plans, which are frozen, are unfunded and the accumulated postretirement benefit obligation is fully recognized on the Consolidated Balance Sheets. Actuarial gains (losses) and prior service costs (benefits) which have not yet been recognized in net income are recognized as a credit (charge) to accumulated other comprehensive income (loss). The credit (charge) to accumulated other comprehensive income (loss), which is reflected net of related tax effects, is subsequently recognized in net income when amortized as a component of postretirement benefit plans expense included in interest expense, net on the Consolidated Statements of Operations. See Note 10. Asset Retirement Obligations The fair value of a liability for an asset retirement obligation is recognized in the period in which it is incurred if a reasonable estimate of fair value can be made. The associated asset retirement costs are capitalized as part of the carrying amount of the asset and depreciated over its remaining estimated useful life. When the assumptions used to estimate a recorded asset retirement obligation change, a revision is recorded to both the asset retirement obligation and the asset retirement cost capitalized to the extent remaining useful life exists. The Company’s asset retirement obligations primarily relate to costs associated with restoring land to its original state. See Note 9. Shipping and Handling Costs Shipping and handling costs are included in cost of products sold and operating expenses on the Consolidated Statements of Operations and are generally passed through to our customers. The Company has elected the practical expedient under Accounting Standards Codification ("ASC") 606, "Revenue from Contracts with Customers," to account for shipping and handling activities as a promise to fulfill the transfer of coke. Share-Based Compensation We measure the cost of employee services in exchange for equity instrument awards and cash awards based on the grant-date fair value of the award. Cash awards and the performance metrics of equity awards are remeasured on a quarterly basis. The market metrics of equity awards are not remeasured. The total cost is recognized over the requisite service period. Award forfeitures are accounted for as they occur. The costs of equity awards and cash awards are recorded to additional paid-in capital and accrued liabilities, respectively, on the Consolidated Balance Sheets. See Note 16. Fair Value Measurements The Company determines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As required, the Company utilizes valuation techniques that maximize the use of observable inputs (levels 1 and 2) and minimize the use of unobservable inputs (level 3) within the fair value hierarchy included in current accounting guidance. Assets and liabilities are classified within the fair value hierarchy based on the lowest level (least observable) input that is significant to the measurement in its entirety. See Note 18. Currency Translation The functional currency of the Company’s Brazilian operations is the Brazilian real. The Company’s Brazil operations translate its assets and liabilities into U.S. dollars at the current exchange rates in effect at the end of the fiscal period. The gains or losses that result from this process are shown as cumulative translation adjustments within accumulated other comprehensive loss in the Consolidated Balance Sheets. The revenue and expense accounts of foreign operations are translated into U.S. dollars at the average exchange rates during the period. Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, “Leases (Topic 842).” ASU 2016-02 requires leases to be recognized as assets and liabilities on the balance sheet for the rights and obligations created by all leases with terms of more than 12 months. Subsequently, the FASB has issued various ASUs to provide further clarification around certain aspects of ASC 842, “Leases.” We adopted the standard effective January 1, 2019 using the modified retrospective transition approach and elected not to adjust prior comparative periods. Upon adoption, the Company recognized right-of-use assets and lease liabilities of $5.1 million at January 1, 2019. See Note 14. In February 2018, the FASB issued ASU 2018-02, “Income Statement-Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” The Company adopted this ASU in the first quarter 2018 and reclassified $1.1 million of deferred tax adjustments to accumulated other comprehensive income (loss) from retained earnings on the December 31, 2017 balance sheet for the tax effects resulting from the Tax Cuts and Jobs Act of 2017. Labor Concentrations As of December 31, 2020, we have approximately 841 employees in the U.S. Approximately 41 percent of our domestic employees, principally at our cokemaking operations, are represented by the United Steelworkers union under various contracts. Additionally, approximately 3 percent of our domestic employees are represented by the International Union of Operating Engineers. During 2020, the labor agreements at Granite City and Haverhill were renewed and will expire on September 1, 2023 and November 1, 2023, respectively. As of December 31, 2020, we have approximately 292 employees at the cokemaking facility in Vitória, Brazil, all of whom are represented by a union under a labor agreement. During 2020, the labor agreement at our Vitória, Brazil facility was renewed for an additional year, and it expires on November 30, 2021.

Acquisitions and Divestitures

Acquisitions and Divestitures	12 Months Ended
	Dec. 31, 2020
Noncontrolling Interest [Abstract]
Acquisitions and Divestitures	3. Acquisitions and Divestitures Simplification Transaction Prior to June 28, 2019, SunCoke owned a 60.4 percent limited partner interest in the Partnership as well as our 2.0 percent general partner interest. The remaining 37.6 percent limited partner interest in the Partnership was held by public unitholders. On June 28, 2019, the Company acquired all 17,727,249 outstanding common units of the Partnership not already owned by SunCoke in exchange for 24,818,149 newly issued SunCoke common shares (the "Simplification Transaction"). Additionally, the final pro-rated quarterly Partnership distribution was settled with 635,502 newly issued SunCoke common shares. Following the completion of the Simplification Transaction, the Partnership became a wholly-owned subsidiary of SunCoke, the Partnership common units ceased to be publicly traded and the Partnership’s incentive distribution rights were eliminated. SunCoke controlled the Partnership both before and after the Simplification Transaction. Therefore, the change in our ownership interest was accounted for as an equity transaction, and no gain or loss was recognized in our Consolidated Statements of Operations for this transaction. The following table summarizes the non-cash (decreases) increases on our balance sheet related to the Simplification Transaction, reflecting the changes in ownership of the Partnership and a step-up in the tax basis in the underlying assets acquired: (Dollars in millions) Noncontrolling interest $ (182.5) Deferred income taxes $ (43.7) Common stock $ 0.3 Additional paid-in capital $ 225.9 Additionally, the Company incurred transaction costs totaling $11.0 million, of which $5.4 million were incurred by SunCoke and were recorded as a reduction to additional paid-in capital on the Consolidated Balance Sheets at December 31, 2019. The remaining transaction costs were incurred by the Partnership, resulting in $4.9 million and $0.4 million of expense included in selling, general and administrative expenses on the Consolidated Statements of Operations for the years ended December 31, 2019 and 2018, respectively. Subsequent to the closing of the Simplification Transaction, SunCoke incurred $0.3 million of legal and consulting costs, which were included in selling, general and administrative expenses on the Consolidated Statements of Operations for the year ended December 31, 2019. The following table summarizes the effects of the changes in the Company's ownership interest in the Partnership on SunCoke's equity in 2019 and 2018. There were no changes in SunCoke's ownership interest in consolidated subsidiaries in 2020. Years Ended December 31, 2019 2018 Net (loss) income attributable to SunCoke Energy, Inc. $ (152.3) $ 26.2 Increase (decrease) in SunCoke Energy, Inc. equity for the purchase of additional interest in the Partnership (1) 182.5 (1.2) Changes from net (loss) income attributable to SunCoke Energy, Inc. and transfers to noncontrolling interest $ 30.2 $ 25.0 (1) During the years ended December 31, 2018 the Company purchased 231,171, of outstanding Partnership common units in the open market for total cash payments of $4.2 million. SunCoke controlled the Partnership both before and after this unit acquisition. Therefore, the cash paid for the Partnership units in excess of the net book value of Partnership interest acquired was recorded as a reduction to additional paid-in capital, reducing SunCoke’s equity balance. Upon the closing of the Simplification Transaction, the Company's program to purchase outstanding Partnership common units was terminated. Divestiture of India Equity Method Investment

Customer Concentrations

Customer Concentrations	12 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Customer Concentrations	4. Customer Concentrations Historically, coke sales were made by the Company under long-term, take-or-pay contracts to three primary customers in the U.S.: ArcelorMittal USA LLC ("AM USA"), AK Steel Holding Corporation ("AK Steel") and United States Steel Corporation ("U.S. Steel"). In March 2020, Cleveland-Cliffs Inc. ("Cliffs") completed the acquisition of AK Steel, and subsequently changed the name of AK Steel to Cleveland-Cliffs Steel Holding Corporation. In December 2020, Cliffs completed the acquisition of AM USA, and subsequently changed the name of AM USA to Cleveland-Cliffs Steel LLC. Collectively, we refer to Cleveland-Cliffs Steel Holding Corporation and Cleveland-Cliffs Steel LLC as "Cliffs Steel." Our contracts with each entity were not impacted by the transactions that occurred in 2020. Contracts with Cliffs Steel are expected to account for approximately 75 percent of our domestic cokemaking capacity in 2021 and approximately 65 percent of our domestic cokemaking capacity in 2022. In 2020, the Company sold approximately 3.8 million tons of coke under long-term, take-or-pay contracts. The tables below shows sales to the Company's significant customers: Year Ended December 31, 2020 Sales and other operating revenue Percent of Company sales and other operating revenue (Dollars in millions) Cliffs Steel / AM USA (1)(2) $ 687.3 51.6 % Cliffs Steel / AK Steel (1)(2) $ 355.8 26.7 % U.S. Steel (3) $ 208.2 15.6 % Years Ended December 31, 2019 2018 Sales and other operating revenue Percent of Company sales and other operating revenue Sales and other operating revenue Percent of Company sales and other operating revenue (Dollars in millions) AM USA (2) $ 786.4 49.1 % $ 695.6 47.9 % AK Steel (2) $ 433.3 27.1 % $ 377.9 26.0 % U.S. Steel (3) $ 255.4 16.0 % $ 206.8 14.3 % (1) Combined sales to Cliffs Steel/AM USA and Cliffs Steel/AK Steel were $1,043.1 million, or 78.3 percent of total Company sales and other operating revenue for the year ended December 31, 2020. (2) Represents revenues included in our Domestic Coke segment. (3) Represents revenues included in our Domestic Coke and Logistics segments. The Company generally does not require any collateral with respect to its receivables. At December 31, 2020, the Company’s receivables balance was primarily due from Cliffs Steel and U.S. Steel, with receivables due of $22.9 million and $6.3 million, respectively. At December 31, 2019, the Company's receivables balance was primarily due from AM USA, AK Steel and U.S. Steel, with receivables due of $19.5 million, $13.2 million, and $7.3 million, respectively. As a result, the Company experiences concentrations of credit risk in its receivables with these customers. These concentrations of credit risk may be affected by changes in economic or other conditions affecting the steel industry.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	5. Income Taxes The components of income before income tax expense (benefit) and loss from equity method investment are as follows: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Domestic $ 6.1 $ (218.6) $ 39.3 Foreign 13.0 15.5 17.7 Total $ 19.1 $ (203.1) $ 57.0 Income tax expense (benefit) consisted of the following: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Current tax (benefit) expense: U.S. federal $ (4.7) $ 0.3 $ 1.4 State (0.3) 3.8 2.1 Foreign 3.2 4.3 4.5 Total current tax (benefit) expense (1.8) 8.4 8.0 Deferred tax expense (benefit): U.S. federal 3.6 (39.3) (3.1) State 8.5 (23.8) (0.3) Total deferred tax expense (benefit) 12.1 (63.1) (3.4) Total $ 10.3 $ (54.7) $ 4.6 The reconciliation of income tax expense at the U.S. statutory rate to income tax expense (benefit) is as follows: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Income tax expense (benefit) at U.S. statutory rate $ 4.0 21.0 % $ (42.7) 21.0 % $ 12.0 21.0 % Increase (reduction) in income taxes resulting from: Income attributable to noncontrolling interests in partnerships (1) (1.1) (5.6) % (0.6) 0.3 % (3.9) (6.8) % State and other income taxes, net of federal income tax effects (2) 7.8 41.2 % (15.0) 7.4 % 1.6 2.8 % Impact of CARES Act (3) (1.5) (7.9) % — — % — — % Logistics goodwill impairment — — % 3.3 (1.7) % — — % Impact of Tax Legislation (4) — — % — — % (4.8) (8.4) % Return to provision adjustments 1.2 6.5 % (0.8) 0.4 % — — % Change in valuation allowance (1.3) (6.9) % 0.6 (0.3) % 0.7 1.2 % Other 1.2 6.0 % 0.5 (0.2) % (1.0) (1.8) % Income tax expense (benefit) at effective tax rate $ 10.3 54.3 % $ (54.7) 26.9 % $ 4.6 8.0 % (1) No income tax expense is reflected in the Consolidated Statements of Operations for income attributable to noncontrolling interests in our Indiana Harbor cokemaking facility or the Partnership prior to the Simplification Transaction discussed in Note 3. (2) A change in the tax filing status of our Convent Marine Terminal in Louisiana from a taxable partnership to a member of the consolidated return group resulted in lower apportioned state tax rates and the revaluation of certain deferred tax assets, which resulted in $6.5 million of deferred income tax expense in 2020. (3) On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security ("CARES Act") was enacted. The enactment of the CARES Act allows the Company to carry back net operating losses generated in 2019 to each of the five years preceding 2019. As a result of the CARES Act, SunCoke expects to receive tax refunds of approximately $4.8 million for prior year taxes paid and recorded a tax benefit of $1.5 million during 2020. (4) On December 22, 2017, the Tax Cuts and Jobs Act ("Tax Legislation") was enacted. The Tax Legislation significantly revised the U.S. corporate income tax structure, including lowering corporate income tax rates. In addition, the SEC staff released Staff Accounting Bulletin 118 on December 23, 2017, which provided for companies to record a provisional impact of the Tax Legislation during a measurement period, not to exceed one year, in situations where companies do not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting under ASC 740, "Income Taxes", for certain income tax effects of the Tax Legislation for the reporting period which includes enactment. Based on an updated analysis of the foreign tax credit rules relating to the new Tax Legislation, the Company revised its estimate of the realizability of its foreign tax credits, resulting in a net $4.8 million benefit during the third quarter of 2018. The tax effects of temporary differences that comprise the net deferred income tax liability from operations are as follows: December 31, 2020 2019 (Dollars in millions) Deferred tax assets: Retirement benefit liabilities $ 6.3 $ 6.4 Black lung benefit liabilities 14.8 12.8 Share-based compensation 4.2 4.7 Federal tax credit carryforward (1) 19.9 20.5 Foreign tax credit carryforward (2) 19.4 14.4 Federal net operating loss (3) 5.3 1.6 Section 163j interest limitation carryforward (4) — 5.7 State tax credit carryforward, net of federal income tax effects (5) 0.3 1.1 State net operating loss carryforward, net of federal income tax effects (6) 12.9 13.6 Other liabilities not yet deductible 11.5 4.4 Total deferred tax assets 94.6 85.2 Less: valuation allowance (7) (19.6) (20.9) Deferred tax asset, net 75.0 64.3 Deferred tax liabilities: Properties, plants and equipment (152.9) (17.9) Investment in partnerships (81.4) (194.0) Total deferred tax liabilities (234.3) (211.9) Net deferred tax liability $ (159.3) $ (147.6) (1) Federal tax credit carryforward expires in 2032 through 2034. (2) Foreign tax credit carryforward expires in 2024 through 2030. (3) Federal net operating loss does not expire. (4) The Tax Legislation generally limits the deductibility of business interest expense to 30 percent (50 percent as a result of CARES Act) of adjusted taxable income. This limitation resulted in a deferred tax asset in 2019 as the interest expense in excess of the limitation is eligible for deduction in future taxable years and has no expiration. In 2020, SunCoke applied the final regulations on section 163(j) released by the IRS on July 28, 2020, which resulted in no interest limitation for the year. (5) State tax credit carryforward, net of federal income tax effects expires in 2021 through 2022. (6) State net operating loss carryforward, net of federal income tax effects expires in 2023 through 2037. (7) Primarily related to state tax credit and net operating loss carryforwards and an $10.7 million allowance against the foreign tax credit carryforward. The Company's consolidated federal income tax returns have been examined by the IRS for all years through the year ended December 31, 2014. SunCoke is currently open to examination by the IRS for tax years ended December 31, 2015 and forward. State and foreign income tax returns are generally subject to examination for a period of three

Inventories

Inventories	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventories	6. Inventories The Company’s inventory consists of metallurgical coal, which is the principal raw material for the Company’s cokemaking operations, coke, which is the finished good sold by the Company to its customers, and materials, supplies and other. These components of inventories were as follows: December 31, 2020 2019 (Dollars in millions) Coal $ 60.6 $ 94.4 Coke 21.1 8.1 Materials, supplies and other 44.9 44.5 Total inventories $ 126.6 $ 147.0

Properties, Plants, and Equipme

Properties, Plants, and Equipment, Net	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Properties, Plants, and Equipment, Net	7. Properties, Plants, and Equipment, Net The components of net properties, plants and equipment were as follows: December 31, 2020 2019 (Dollars in millions) Coke and energy plant, machinery and equipment $ 2,009.3 $ 1,968.2 Logistics plant, machinery and equipment 157.3 147.9 Land and land improvements 104.5 106.0 Construction-in-progress 47.4 29.5 Other 42.4 42.3 Gross investment, at cost 2,360.9 2,293.9 Less: accumulated depreciation (1,032.9) (903.7) Total properties, plants and equipment, net $ 1,328.0 $ 1,390.2

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	8. Goodwill and Other Intangible Assets A significant portion of our logistics business has historically been from long-term, take-or-pay contracts with Murray American Coal, Inc. ("Murray") and Foresight Energy LLC ("Foresight"), which have been adversely impacted by declining coal export prices and domestic demand. Murray filed for Chapter 11 bankruptcy on October 29, 2019. Foresight engaged outside counsel and financial advisors to assess restructuring options during 2019 and subsequently filed for Chapter 11 bankruptcy on March 10, 2020. Both Murray and Foresight's contracts with CMT were subsequently rejected by the bankruptcy courts. Impairment of Goodwill The Company concluded the impact of the events discussed above could more likely than not reduce the fair value of the Logistics reporting unit below its carrying value, requiring SunCoke to perform its annual goodwill test as of September 30, 2019. The fair value of the Logistics reporting unit, which was determined based on a discounted cash flow analysis, did not exceed the carrying value of the reporting unit. Key assumptions in our goodwill impairment test included reduced forecasted volumes and reduced rates from Foresight, no further business from Murray, incremental merchant business and a discount rate of 12 percent, representing the estimated weighted average cost of capital for this business line. As a result, the Company recorded a $73.5 million non-cash, pre-tax impairment charge to the Logistics segment on the Consolidated Statements of Operations during 2019, which represents a full impairment of the Logistics goodwill balance. Goodwill allocated to SunCoke's reportable segments as of December 31, 2020 and December 31, 2019 and changes in the carrying amount of goodwill during the fiscal year ended December 31, 2020 are shown below. There were no changes in the carrying amount of goodwill during the fiscal year ended December 31, 2020. Domestic Coke Logistics Total (Dollars in millions) Net balances at December 31, 2018 $ 3.4 $ 73.5 $ 76.9 Impairment — (73.5) (73.5) Net balances at December 31, 2019 and 2020 $ 3.4 $ — $ 3.4 Impairment of Long-Lived Assets As a result of our logistics customers' events discussed above, CMT's long-lived assets, including customer contracts, customer relationships, permits and properties, plant and equipment, were also assessed for impairment as of September 30, 2019. The Company re-evaluated its projections for throughput volumes, pricing and customer performance against the existing long-term, take-or-pay contracts. The resulting undiscounted cash flows were lower than the carrying value of the asset group. Therefore, the Company assessed the fair value of the asset group to measure the amount of impairment. The fair value of the CMT long-lived assets was determined to be $112.1 million based on discounted cash flows, asset replacement cost and adjustments for capacity utilization, which are considered Level 3 inputs in the fair value hierarchy as defined in Note 18. Key assumptions in our discounted cash flows included reduced forecasted volumes and reduced rates from Foresight, no further business from Murray, incremental merchant business and a discount rate of 11 percent, representing the estimated weighted average cost of capital for this asset group. As a result, during 2019, the Company recorded a total non-cash, pre-tax long-lived asset impairment charge of $173.9 million included in long-lived asset and goodwill impairment on the Consolidated Statements of Operations, all of which was attributable to the Logistics segment. The charge included an impairment of CMT's long-lived intangible assets of $113.3 million and of CMT's property, plant and equipment of $60.6 million. Components of other intangible assets, net The components of other intangible assets, net, excluding fully amortized intangible assets, were as follows: December 31, 2020 December 31, 2019 Weighted - Average Remaining Amortization Years Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net (Dollars in millions) Customer contracts — $ — $ — $ — $ 7.7 $ 7.2 $ 0.5 Customer relationships 4 6.7 4.5 2.2 6.7 3.9 2.8 Permits 22 31.7 1.7 30.0 31.7 0.3 31.4 Other 30 1.6 — 1.6 — — — Total $ 40.0 $ 6.2 $ 33.8 $ 46.1 $ 11.4 $ 34.7 The permits above represent the environmental and operational permits required to operate a coal export terminal in accordance with the U.S. Environmental Protection Agency ("EPA") and other regulatory bodies. Intangible assets are amortized over their useful lives in a manner that reflects the pattern in which the economic benefit of the asset is consumed. The permits’ useful lives were estimated to be 27 years at acquisition based on the expected useful life of the significant operating equipment at the facility. We have historical experience of renewing and extending similar arrangements at our other facilities and intend to continue to renew our permits as they come up for renewal for the foreseeable future. The permits were renewed regularly prior to our acquisition of CMT. These permits have an average remaining renewal term of approximately 3.4 years. Total amortization expense for intangible assets subject to amortization was $2.5 million, $8.8 million and $11.1 million for the years ended December 31, 2020, 2019 and 2018, respectively. Based on the carrying value of finite-lived intangible assets as of December 31, 2020, we estimate amortization expense for each of the next five years as follows: (Dollars in millions) 2021 $ 2.0 2022 2.0 2023 2.0 2024 1.9 2025 1.5 Thereafter 24.4 Total $ 33.8

Asset Retirement Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation [Abstract]
Asset Retirement Obligations	9. Asset Retirement Obligations The Company has asset retirement obligations, primarily in the Domestic Coke segment, related to certain contractual obligations. These contractual obligations mostly relate to costs associated with restoring land to its original state, and may require the retirement and removal of long-lived assets from certain cokemaking properties as well as other reclamation obligations related to our former coal mining business. The Federal Surface Mining Control and Reclamation Act of 1977 and similar state statutes require that mine property be restored in accordance with specified standards and an approved reclamation plan. We do not have any unrecorded asset retirement obligations. The following table provides a reconciliation of changes in the asset retirement obligation from operations during each period: Years ended December 31, 2020 2019 Asset retirement obligation at beginning of year $ 15.3 $ 14.6 Liabilities settled (0.1) (1.2) Accretion expense (1) 1.1 1.0 Revisions in estimated cash flows (2) (4.9) 0.9 Asset retirement obligation at end of year (3) $ 11.4 $ 15.3 (1) Included in cost of products sold and operating expenses on the Consolidated Statements of Operations. (2) Revisions of estimated cash flows in 2020 were primarily due to the identification of more cost efficient demolition methods as well as the timing of projected spending on certain obligations.

Retirement Benefits Plans

Retirement Benefits Plans	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Retirement Benefits Plans	10. Retirement Benefits Plans Postretirement Health Care and Life Insurance Plans The Company has plans which provide health care and life insurance benefits for many of its retirees (“postretirement benefit plans”). The postretirement benefit plans are unfunded and the costs are borne by the Company. Effective January 1, 2011, postretirement medical benefits for future retirees were phased out or eliminated for non-mining employees with less than ten years of service. Postretirement benefit plans expense consisted of the following components: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Interest cost on benefit obligations $ 0.7 $ 1.1 $ 1.0 Amortization of: Actuarial losses 0.7 0.6 0.6 Prior service benefit (0.5) (0.6) (0.7) Total expense $ 0.9 $ 1.1 $ 0.9 Postretirement benefit plans expense is determined using actuarial assumptions as of the beginning of the year or using weighted-average assumptions when curtailments, settlements and/or other events require a plan remeasurement. The following assumptions were used to determine postretirement benefit plans expense: December 31, 2020 2019 2018 Discount rate 2.90 % 4.00 % 3.35 % The following amounts were recognized as components of other comprehensive income (loss) before related tax impacts: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Reclassifications to earnings of: Actuarial loss amortization $ 0.7 $ 0.6 $ 0.6 Prior service benefit amortization (0.5) (0.6) (0.7) Retirement benefit plan funded status Actuarial (losses) gains (2.0) (1.0) 0.8 $ (1.8) $ (1.0) $ 0.7 The following table sets forth the components of the changes in benefit obligations: Years Ended December 31, 2020 2019 (Dollars in millions) Benefit obligation at beginning of year $ 27.4 $ 28.2 Interest cost 0.7 1.1 Actuarial loss 2.0 1.0 Benefits paid (2.6) (2.9) Benefit obligation at end of year (1) $ 27.5 $ 27.4 (1) The current portion of retirement benefit liabilities, which totaled $2.8 million and $2.9 million at December 31, 2020 and 2019, respectively, is classified in accrued liabilities on the Consolidated Balance Sheets. The following table sets forth the cumulative amounts not yet recognized in net (loss) income: Years Ended December 31, 2020 2019 (Dollars in millions) Cumulative amounts not yet recognized in net (loss) income: Actuarial losses $ 12.1 $ 10.8 Prior service benefits (1.5) (2.0) Accumulated other comprehensive loss (before related tax benefit) $ 10.6 $ 8.8 The expected benefit payments through 2030 for the postretirement benefit plan are as follows: (Dollars in millions) Year ending December 31: 2021 $ 2.8 2022 $ 2.6 2023 $ 2.4 2024 $ 2.2 2025 $ 2.0 2026 through 2030 $ 8.1 The measurement date for the Company’s postretirement benefit plans is December 31. The following discount rates were used to determine the benefit obligation: December 31, 2020 2019 Discount rate 2.00 % 2.90 % The health care cost trend assumption used at both December 31, 2020 and 2019 to compute the accumulated postretirement benefit obligation for the postretirement benefit plans was 6.25 percent, which is assumed to decline gradually to 5.00 percent in 2026 and to remain at that level thereafter. Defined Contribution Plans The Company has defined contribution plans which provide retirement benefits for certain of its employees. The Company’s contributions, which are principally based on the Company’s pretax income and the aggregate compensation levels of participating employees and are charged against income as incurred, amounted to $6.6 million, $6.8 million and $6.5 million for the years ended December 31, 2020, 2019 and 2018, respectively.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Accrued Liabilities	11. Accrued Liabilities Accrued liabilities consist of following: December 31, 2020 2019 (Dollars in millions) Accrued benefits $ 18.3 $ 21.7 Current portion of postretirement benefit obligation 2.8 2.9 Other taxes payable 9.8 9.9 Current portion of black lung liability 4.6 4.6 Accrued legal 6.4 2.7 Other 7.9 5.5 Total accrued liabilities $ 49.8 $ 47.3

Debt and Financing Obligations

Debt and Financing Obligations	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt and Financing Obligations	12. Debt and Financing Obligations Total debt and financing obligations consisted of the following: December 31, 2020 2019 (Dollars in millions) 7.50 percent senior notes, due 2025 ("2025 Senior Notes") $ 587.3 $ 650.0 $400.0 revolving credit facility, due 2024 ("Revolving Facility") 88.3 143.3 5.35 percent financing obligation, due 2024 14.9 7.2 Total borrowings $ 690.5 $ 800.5 Original issue discount (3.3) (4.3) Debt issuance costs (10.3) (13.3) Total debt and financing obligation $ 676.9 $ 782.9 Less: current portion of long-term debt and financing obligation 3.0 2.9 Total long-term debt and financing obligation $ 673.9 $ 780.0 2025 Senior Notes The 2025 Senior Notes were the senior unsecured obligations of the Partnership. On August 5, 2019, SunCoke entered into a supplemental indenture relating to the 2025 Senior Notes, pursuant to which SunCoke has provided a full and unconditional parent guarantee of these obligations. As of January 1, 2020, the Partnership merged with and into Finance Corp., at which time the 2025 Senior Notes became the senior unsecured obligations of Finance Corp, which is a wholly-owned subsidiary of the Company. Subsequently, Finance Corp and SunCoke entered into a supplemental indenture relating to the 2025 Senior Notes to acknowledge the merger and clarify certain terms of the indenture. Interest on the 2025 Senior Notes is payable semi-annually in cash in arrears on June 15 and December 15 of each year. The Company may redeem some or all of the 2025 Senior Notes at specified redemption prices plus accrued and unpaid interest, if any, to the redemption date. On or after June 15, 2020, the Company also may redeem up to 35 percent of the 2025 Senior Notes at a price equal to 105.6 percent of the principal amount, plus accrued and unpaid interest, if any, to the redemption date. Beginning June 15, 2021, the premium on the redemption price will decrease by 1.9 percent on an annual basis through June 15, 2023. On or after June 15, 2023 the redemption price will equal 100 percent of the principal amount. During 2020, the Company repurchased $62.7 million face value of outstanding 2025 Senior Notes in the open market for $55.9 million of cash payments, resulting in a gain on extinguishment of debt on the Consolidated Statements of Operations of $5.7 million, net of the write-off of unamortized debt issuance costs and original issue discount. The Company is obligated to offer to purchase all or a portion of the 2025 Senior Notes at a price of (a) 101 percent of their principal amount, together with accrued and unpaid interest, if any, to the date of purchase, upon the occurrence of certain change of control events and (b) 100 percent of their principal amount, together with accrued and unpaid interest, if any, to the date of purchase, upon the occurrence of certain asset dispositions. These restrictions and prohibitions are subject to certain qualifications and exceptions set forth in the Indenture, including without limitation, reinvestment rights with respect to the proceeds of asset dispositions. The 2025 Senior Notes contain covenants that, among other things, limit the Company's ability and the ability of certain subsidiaries to (i) incur indebtedness, (ii) pay dividends or make other distributions, (ii) prepay, redeem or repurchase certain subordinated debt, (iv) make loans and investments, (v) sell assets, (vi) incur liens, (vii) enter into transactions with affiliates, (viii) enter into agreements restricting the ability of subsidiaries to pay dividends and (ix) consolidate or merge. Revolving Facility The proceeds of any borrowings made under the Revolving Facility can be used to finance working capital needs, acquisitions, capital expenditures and for other general corporate purposes. The obligations under the credit agreement are guaranteed by certain of the Company’s subsidiaries and secured by liens on substantially all of the Company’s and the guarantors’ assets pursuant to a guarantee and collateral agreement. As of December 31, 2020, the Revolving Facility had letters of credit outstanding of $11.8 million and $88.3 million outstanding balance, leaving $299.9 million available. Additionally, the Company has certain letters of credit totaling $11.5 million, which do not reduce the Revolving Facility's available balance. Commitment fees are based on the unused portion of the Revolving Facility at a rate of 0.25 percent. Borrowings under the Revolving Facility bear interest, at SunCoke’s option, at either (i) a rate per annum equal to either the adjusted Eurodollar Rate, which currently is the London Interbank Offered Rate (“LIBOR”) plus 2.0 percent or (ii) an alternate base rate (“ABR”) plus 1.0 percent. The spread is subject to change based on SunCoke's consolidated leverage ratio, as defined in the credit agreement. The weighted-average interest rate for borrowings outstanding under the Revolving Facility was 2.6 percent during 2020. Financing Obligation The Company has sale-leaseback arrangements related to certain coke and logistics equipment. The arrangements have an initial period of 48 months beginning December 2020, and an early buyout option after 36 months to purchase the equipment at a fixed rate. The arrangements are accounted for as financing transactions, resulting in financing obligations on the Consolidated Balance Sheets. Covenants Under the terms of the Revolving Facility, the Company is subject to a maximum consolidated leverage ratio of 4.50:1.00 and a minimum consolidated interest coverage ratio of 2.50:1.00. The Company's debt agreements contains other covenants and events of default that are customary for similar agreements and may limit our ability to take various actions including our ability to pay a dividend or repurchase our stock. If we fail to perform our obligations under these and other covenants, the lenders' credit commitment could be terminated and any outstanding borrowings, together with accrued interest, under the Revolving Facility could be declared immediately due and payable. The Company has a cross default provision that applies to our indebtedness having a principal amount in excess of $35 million. As of December 31, 2020, the Company was in compliance with all debt covenants. We do not anticipate violation of these covenants nor do we anticipate that any of these covenants will restrict our operations or our ability to obtain additional financing. Maturities As of December 31, 2020, the combined aggregate amount of maturities for long-term borrowings for each of the next five years is as follows: (Dollars in millions) 2021 $ 3.0 2022 3.2 2023 3.3 2024 93.7 2025 587.3 2026-Thereafter — Total $ 690.5

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	13. Commitments and Contingent Liabilities Legal Matters Between 2005 and 2012, the EPA and the Ohio Environmental Protection Agency (“OEPA”) issued Notices of Violations (“NOVs”), alleging violations of air emission operating permits for our Haverhill and Granite City cokemaking facilities. We worked in a cooperative manner with the EPA, the OEPA and the Illinois Environmental Protection Agency to address the allegations and, in November 2014, entered into a consent decree with these parties in federal district court in the Southern District of Illinois. The consent decree included a civil penalty paid in December 2014, and a commitment to undertake capital projects to improve reliability and enhance environmental performance. The Haverhill project was completed in 2016, but completion of the Granite City project was delayed to June 2019, with SunCoke agreeing to pay an immaterial amount associated with the delay. Between 2010 and 2016, SunCoke Energy also received certain NOVs, Findings of Violations (“FOVs”), and information requests from the EPA, alleging violations of air operating permit conditions related to our Indiana Harbor cokemaking facility. To reach a settlement of these NOVs and FOVs, we met regularly with the EPA, the Indiana Department of Environmental Management and Cokenergy, LLC., an independent power producer that processes hot flue gas from our Indiana Harbor facility to reduce the sulfur and particulate content and produce steam and electricity. A consent decree among the parties was entered by the federal district court in the Northern District of Indiana during the fourth quarter of 2018. The settlement included a civil penalty paid in the fourth quarter of 2018, and implementation of certain capital projects, completed during the fourth quarter of 2019, to improve reliability and environmental performance of the coke ovens at the facility. The Company is a party to certain other pending and threatened claims, including matters related to commercial disputes, employment claims, personal injury claims, common law tort claims, and environmental claims. Although the ultimate outcome of these claims cannot be ascertained at this time, it is reasonably possible that some portion of these claims could be resolved unfavorably to the Company. Management of the Company believes that any liability which may arise from these claims would not have a material adverse impact on our consolidated financial statements. SunCoke's threshold for disclosing material environmental legal proceedings involving a government authority where potential monetary sanctions are involved is $1 million. Black Lung Benefit Liabilities The Company has obligations related to coal workers’ pneumoconiosis, or black lung, benefits to certain of our former coal miners and their dependents. Such benefits are provided for under Title IV of the Federal Coal Mine and Safety Act of 1969 and subsequent amendments, as well as for black lung benefits provided in the states of Virginia, Kentucky and West Virginia pursuant to workers’ compensation legislation. The Patient Protection and Affordable Care Act (“PPACA”), which was implemented in 2010, amended previous legislation related to coal workers’ black lung obligations. PPACA provides for the automatic extension of awarded lifetime benefits to surviving spouses and changes the legal criteria used to assess and award claims. We act as a self-insurer for both state and federal black lung benefits and adjust our liability each year based upon actuarial calculations of our expected future payments for these benefits. Our independent actuarial consultants calculate the present value of the estimated black lung liability annually based on actuarial models utilizing our population of former coal miners, historical payout patterns of both the Company and the industry, actuarial mortality rates, disability incidence, medical costs, death benefits, dependents, discount rates and the current federally mandated payout rates. The estimated liability may be impacted by future changes in the statutory mechanisms, modifications by court decisions and changes in filing patterns driven by perceptions of success by claimants and their advisors, the impact of which cannot be estimated. The following table summarizes discount rates utilized, active claims and the total black lung liabilities: December 31, 2020 2019 Discount rate (1) 2.0 % 2.9 % Active claims 309 324 Total black lung liability (dollars in millions) (2) $ 64.6 $ 55.1 (1) The discount rate is determined based on a portfolio of high-quality corporate bonds with maturities that are consistent with the estimated duration of our black lung obligations. A decrease of 25 basis points in the discount rate would have increased black lung expense by $1.6 million in 2020. (2) The current portion of the black lung liability was $4.6 million at both December 31, 2020 and 2019, respectively, and was included in accrued liabilities on the Consolidated Balance Sheets. The following table summarizes annual black lung payments and expense: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Payments $ 6.0 $ 5.2 $ 6.3 Expense (1) $ 15.4 $ 10.9 $ 5.4 (1) Expenses incurred in excess of annual accretion of the black lung liability primarily reflect the impact of changes in discount rates as well as increases in expected future claims as a result of higher refiling and approval rate assumptions.

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	14. Leases The Company leases land, office space, equipment, railcars and locomotives. Arrangements are assessed at inception to determine if a lease exists and, with the adoption of ASC 842, “Leases,” right-of-use (“ROU”) assets and lease liabilities are recognized based on the present value of lease payments over the lease term. Because the Company’s leases do not provide an implicit rate of return, the Company uses its incremental borrowing rate at the inception of a lease to calculate the present value of lease payments. Our incremental borrowing rate is determined through market sources for secured borrowings and approximates the interest rate at which we could borrow on a collateralized basis with similar terms and payments in similar economic environments. The Company has elected to apply the short-term lease exception for all asset classes, therefore, excluding all leases with a term of less than 12 months from the balance sheet, and will recognize the lease payments in the period they are incurred. Additionally, the Company has elected to account for lease and nonlease components of an arrangement, such as assets and services, as a single lease component for all asset classes. Certain of our long-term leases include one or more options to renew or to terminate, with renewal terms that can extend the lease term from one month to 50 years. The impact of lease renewals or terminations are included in the expected lease term to the extent the Company is reasonably certain to exercise the renewal or termination. The Company's finance leases are immaterial to our consolidated financial statements. The components of lease expense were as follows: Year ended December 31, 2020 Year ended December 31, 2019 (Dollars in millions) Operating leases: Cost of products sold and operating expenses $ 1.8 $ 1.9 Selling, general and administrative expenses 0.5 0.5 $ 2.3 $ 2.4 Short-term leases: Cost of products sold and operating expenses (1)(2) 6.4 9.3 Total lease expense $ 8.7 $ 11.7 (1) Includes expenses for month-to-month equipment leases, which are classified as short-term as the Company is not reasonably certain to renew the lease term beyond one month. (2) Includes variable lease expenses, which are immaterial to the consolidated financial statements. Supplemental balance sheet information related to leases was as follows: Financial Statement Classification December 31, 2020 December 31, 2019 (Dollars in millions) Operating ROU assets Deferred charges and other assets $ 10.8 $ 12.4 Operating lease liabilities: Current operating lease liabilities Accrued liabilities $ 2.0 $ 1.9 Noncurrent operating lease liabilities Other deferred credits and liabilities 8.2 9.8 Total operating lease liabilities $ 10.2 $ 11.7 The weighted average remaining lease term and weighted average discount rate were as follows: December 31, 2020 December 31, 2019 Weighted average remaining lease term of operating leases 7.3 years 7.9 years Weighted average discount rate of operating leases 4.7 % 4.8 % Supplemental cash flow information related to leases was as follows: Year Ended December 31, 2020 Year Ended December 31, 2019 (Dollars in millions) Operating cash flow information: Cash paid for amounts included in the measurement of operating lease liabilities $ 2.3 $ 3.9 Non-cash activity: ROU assets obtained in exchange for new operating lease liabilities $ 0.2 $ 7.9 Maturities of operating lease liabilities as of December 31, 2020 are as follows: (Dollars in millions) Year ending December 31: 2021 $ 2.3 2022 1.7 2023 1.4 2024 1.3 2025 1.3 2026-Thereafter 4.0 Total lease payments 12.0 Less: imputed interest 1.8 Total lease liabilities $ 10.2

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Accumulated Other Comprehensive Loss	15. Accumulated Other Comprehensive Loss The following tables set forth the changes in the balance of accumulated other comprehensive loss, net of tax, by component: Benefit Plans Currency Translation Adjustments Total (Dollars in millions) At December 31, 2018 $ (6.0) $ (7.1) $ (13.1) Other comprehensive loss before reclassifications / adjustments — (0.6) (0.6) Retirement benefit plans funded status adjustment (0.7) — (0.7) Net current period change in accumulated other comprehensive loss (0.7) (0.6) (1.3) At December 31, 2019 $ (6.7) $ (7.7) $ (14.4) Other comprehensive loss before reclassifications / adjustments 0.1 (1.2) (1.1) Retirement benefit plans funded status adjustment (1.6) — (1.6) Net current period change in accumulated other comprehensive loss (1.5) (1.2) (2.7) At December 31, 2020 $ (8.2) $ (8.9) $ (17.1) The tax benefit associated with the Company's benefit plans as of December 31, 2020 and 2019 was $2.4 million and $2.1 million, respectively. The (decrease) increase in net income due to reclassification adjustments from accumulated other comprehensive income were as follows (1) : December 31, 2020 2019 2018 (Dollars in millions) Recognition of accumulated currency translation loss upon sale of equity method investment in VISA SunCoke $ — $ — $ (9.0) Amortization of benefit plans to net income: (2) Actuarial loss $ (0.6) $ (0.6) $ (0.6) Prior service benefit 0.5 0.6 0.7 Total, net of tax (3) $ (0.1) $ — $ (8.9) (1) Amounts in parentheses indicate debits to net income. (2) These accumulated other comprehensive (income) loss components are included in the computation of postretirement benefit plan expense (benefit) and included in interest expense, net on the Consolidated Statements of Operations. See Note 10.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share-Based Compensation	16. Share-Based Compensation Equity Classified Awards The SunCoke Energy, Inc. Long-Term Performance Enhancement Plan (“SunCoke LTPEP”) provides for the grant of equity-based awards including stock options and share units, or restricted stock, to the Company’s directors, officers, and other employees, advisors, and consultants who are selected by the plan committee for participation in the SunCoke LTPEP. All awards vest immediately upon a change in control and a qualifying termination of employment as defined by the SunCoke LTPEP. The plan authorizes the issuance of (i) 1,600,000 shares of SunCoke Energy common stock issuable upon the adjustment of Sunoco, Inc. equity awards in connection with the Separation and Distribution Agreement between Sunoco, Inc. and SunCoke and (ii) up to 7,500,000 shares, which reflects the 6,000,000 shares initially authorized under the Plan and an additional 1,500,000 shares to be issued under the Plan pursuant to an amendment effective February 14, 2018, of SunCoke Energy, Inc. common stock pursuant to new awards under the SunCoke LTPEP. The Company measures the cost of employee services in exchange for an award of equity instruments based on the grant-date fair value of the award. The performance metrics of equity awards are remeasured on a quarterly basis for updates to the probability of achievement. The market metrics of equity awards are not remeasured. The total cost is recognized over the requisite service period. Award forfeitures are accounted for as they occur. Stock Options There were no stock options granted by the Company during 2020. The Company granted the following stock options during the years ended December 31, 2019 and 2018, with an exercise price equal to the closing price of our common stock on the date of grant: Weighted Average Per Share Number of Shares Exercise Price Weighted Average Grant Date Fair Value Traditional stock options: 2019 grant 267,897 $ 9.87 $ 4.09 2018 grant 78,447 $ 10.49 $ 5.38 The stock options vest in three equal annual installments beginning one year from the date of grant. The stock options expire ten years from the date of grant. The Company calculates the value of each employee stock option, estimated on the date of grant, using the Black-Scholes option pricing model with a Monte Carlo simulation for the performance based options. The weighted-average fair value of employee stock options granted during the years ended December 31, 2019 and 2018 was based on using the following weighted-average assumptions: 2019 2018 Risk free interest rate 2 % 3 % Expected term 6 years 6 years Volatility 53 % 52 % Dividend yield 2 % — % The risk-free interest rate assumption is based on the U.S. Treasury yield curve at the date of grant for periods which approximate the expected life of the option. The expected term of the employee options represent the average contractual term adjusted by the average vesting period of each option tranche. We based our expected volatility on our historical volatility over our entire available trading history. The dividend yield assumption is based on the Company’s expectation of dividend payouts at the time of grant. The following table summarizes information with respect to common stock option awards outstanding as of December 31, 2020 and stock option activity during the fiscal year then ended: Number of Weighted Weighted Average Remaining Contractual Term (years) Aggregate Outstanding at December 31, 2019 3,136,831 $ 15.02 4.3 $ 0.3 Exercised (2,825) $ 3.80 Forfeited (33,146) $ 12.25 Outstanding at December 31, 2020 3,100,860 $ 15.02 3.2 $ 0.1 Exercisable at December 31, 2020 2,733,205 $ 15.69 2.4 $ 0.1 Expected to vest at December 31, 2020 367,655 $ 10.01 7.8 $ — Intrinsic value for stock options is defined as the difference between the current market value of our common stock and the exercise price of the stock options. Total intrinsic value of stock options exercised in 2020 was immaterial and was $0.8 million on options exercised during 2018. There were no stock options exercised during 2019. Restricted Stock Units The Company granted the following restricted stock units ("RSUs") during the years ended December 31, 2020, 2019 and 2018: Number of RSUs Weighted Average Grant-Date Fair Value per Unit Grant Date Fair Value (Dollars in millions) 2020 grants 304,332 $ 6.04 $ 1.8 2019 grants 136,425 $ 9.87 $ 1.3 2018 grants 32,128 $ 10.49 $ 0.3 The RSUs vest in three annual installments beginning one year from the date of grant. The following table summarizes information with respect to RSUs outstanding as of December 31, 2020 and RSU activity during the fiscal year then ended: Number of Weighted Nonvested at December 31, 2019 165,384 $ 9.95 Granted 304,332 $ 6.04 Vested (63,729) $ 9.97 Forfeited — $ — Nonvested at December 31, 2020 405,987 $ 7.02 Total grant date fair value of RSUs vested was $0.6 million, $0.2 million and $1.2 million during 2020, 2019 and 2018, respectively. Performance Share Units The Company grants performance share units ("PSUs"), which represent the right to receive shares of the Company's common stock, contingent upon the attainment of Company performance and market goals and continued employment. The Company granted the following PSUs during the years ended December 31, 2020, 2019 and 2018: Number of PSUs Fair Value per Unit Grant Date Fair Value (Dollars in millions) 2020 grant (1) 228,248 $ 6.70 $ 1.5 2019 grant (1) 227,378 $ 10.79 $ 2.5 2018 grant (1) 96,389 $ 11.36 $ 1.1 (1) The service period for the 2020, 2019, and 2018 PSUs ends on December 31, 2022, 2021 and 2020, and the awards will vest during the first quarter of 2023, 2022 and 2021, respectively. The PSU grants were split 50/50 between the Company's three three three The following table summarizes information with respect to unearned PSUs outstanding as of December 31, 2020 and PSU activity during the fiscal year then ended: Number of Weighted Nonvested at December 31, 2019 575,363 $ 11.20 Granted 228,248 $ 6.70 Vested (92,992) $ 11.40 Forfeited (25,316) $ 11.40 Nonvested at December 31, 2020 685,303 $ 9.76 Liability Classified Awards Restricted Stock Units Settled in Cash During the years ended December 31, 2020, 2019 and 2018, the Company issued 263,998, 147,851 and 98,364 restricted stock units to be settled in cash ("Cash RSUs"), respectively, which vest in three annual installments beginning one year from the grant date. The weighted average grant date fair value of the Cash RSUs granted during the years ended December 31, 2020, 2019 and 2018, was $6.04, $9.66 and $10.71, respectively, and was based on the closing price of our common stock on the day of grant. The Cash RSU liability at December 31, 2020 was adjusted based on the closing price of our common stock on December 31, 2020 of $4.35 per share. The Cash RSU liability at December 31, 2020 was not material. Cash Incentive Award The Company also granted share-based compensation to eligible participants under the SunCoke Energy, Inc. Long-Term Cash Incentive Plan ("SunCoke LTCIP"), which became effective January 1, 2016. The SunCoke LTCIP is designed to provide for performance-based, cash-settled awards. All awards vest immediately upon a change in control and a qualifying termination of employment as defined by the SunCoke LTCIP. The Company issued a grant date fair value award of $2.0 million, $0.6 million and $1.0 million during the years ended December 31, 2020, 2019 and 2018, respectively, for which the service periods end on December 31, 2023, 2022 and 2021, respectively, and the awards will vests during the first quarter of 2024, 2023 and 2022, respectively. The 2019 and 2018 awards are split 50/50 between the Company's three-year cumulative Adjusted EBITDA performance and the Company's three The cash incentive award liability at December 31, 2020 was adjusted based on the Company's current performance related to the above awards. The cash incentive award liability at December 31, 2020 was not material. Summary of Share-Based Compensation Expense Below is a summary of the compensation expense, unrecognized compensation costs, the period for which the unrecognized compensation cost is expected to be recognized over and the estimated forfeiture rate for each award: Years Ended December 31, 2020 2019 2018 2020 2019 2018 December 31, 2020 Compensation Expense (1) Net of tax Unrecognized Compensation Cost Recognition Period (Dollars in millions) (Dollars in millions) (Years) Equity Awards: Stock Options $ 0.3 $ 1.1 $ 0.5 $ 0.3 $ 0.9 $ 0.4 $ 0.1 1.1 RSUs 1.9 1.0 0.4 1.5 0.9 0.3 $ 0.5 1.9 PSUs 1.5 2.2 1.9 1.2 1.8 1.7 $ 1.5 1.5 Total equity awards $ 3.7 $ 4.3 $ 2.8 $ 3.0 $ 3.6 $ 2.4 Liability Awards: Cash RSUs $ 0.8 $ 0.9 $ 0.8 $ 0.6 $ 0.7 $ 0.6 $ 0.6 1.9 Cash incentive award 0.6 0.4 0.9 0.4 0.3 0.7 $ 1.2 1.9 Total liability awards $ 1.4 $ 1.3 $ 1.7 $ 1.0 $ 1.0 $ 1.3 (1) Compensation expense is recognized by the Company in selling, general and administrative expenses on the Consolidated Statements of Operations.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share	17. Earnings Per Share Basic earnings per share (“EPS”) has been computed by dividing net (loss) income available to SunCoke Energy, Inc. by the weighted average number of shares outstanding during the period. Except where the result would be anti-dilutive, diluted earnings per share has been computed to give effect to share-based compensation awards using the treasury stock method. The following table sets forth the reconciliation of the weighted-average number of common shares used to compute basic earnings per share to those used to compute diluted EPS: Years Ended December 31, 2020 2019 2018 (Shares in millions) Weighted-average number of common shares outstanding-basic 83.0 76.8 64.7 Add: effect of dilutive share-based compensation awards 0.2 — 0.8 Weighted-average number of shares-diluted 83.2 76.8 65.5 The following table shows stock options, restricted stock units, and performance stock units that are excluded from the computation of diluted earnings per share as the shares would have been anti-dilutive: Years Ended December 31, 2020 2019 2018 (Shares in millions) Stock options 3.2 3.0 2.7 Restricted stock units 0.2 0.1 — Performance stock units 0.3 0.4 0.1 Total 3.7 3.5 2.8

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	18. Fair Value Measurements The Company measures certain financial and non-financial assets and liabilities at fair value on a recurring basis. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants on the measurement date. Fair value disclosures are reflected in a three-level hierarchy, maximizing the use of observable inputs and minimizing the use of unobservable inputs. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability on the measurement date. The three levels are defined as follows: • Level 1—inputs to the valuation methodology are quoted prices (unadjusted) for an identical asset or liability in an active market. • Level 2—inputs to the valuation methodology include quoted prices for a similar asset or liability in an active market or model-derived valuations in which all significant inputs are observable for substantially the full term of the asset or liability. • Level 3—inputs to the valuation methodology are unobservable and significant to the fair value measurement of the asset or liability. Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis Cash Equivalents Certain assets and liabilities are measured at fair value on a recurring basis. The Company’s cash equivalents were measured at fair value at December 31, 2020 and December 31, 2019 based on quoted prices in active markets for identical assets. These inputs are classified as Level 1 within the valuation hierarchy. CMT Contingent Consideration In connection with the CMT acquisition, the Company entered into a contingent consideration arrangement that required us to make future payments through 2022 to The Cline Group based on future volume over a specified threshold, price and contract renewals. Prior to the termination of the related contract in 2020, the fair value of the contingent consideration was estimated based on a probability-weighted analysis using significant inputs that are not observable in the market, or Level 3 inputs. Due to the change in market and customer conditions in 2019, further described in Note 8, we decreased our forecasted projections, which were classified as Level 3 inputs. The decrease in forecasted projections, as well as a payment made in 2019, resulted in a reduction of the contingent consideration liability, primarily included in other deferred credits and liabilities on the Consolidated Balance Sheets, to zero at December 31, 2019 from $5.0 million at December 31, 2018. During 2018, volumes and improved volume projections resulted in an increase of $2.5 million to the fair value of the contingent consideration balance. Changes in fair value were recorded to costs of products sold and operating expenses on the Consolidated Statements of Operations during 2019 and 2018. Certain Financial Assets and Liabilities not Measured at Fair Value At December 31, 2020 and 2019, the fair value of the Company’s long-term debt was estimated to be $683.9 million and $776.1 million, respectively, compared to a carrying amount of $690.5 million and $800.5 million, respectively. These fair values were estimated by management based upon estimates of debt pricing provided by financial institutions which are considered Level 2 inputs.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	19. Revenue from Contracts with Customers Cokemaking Substantially all our coke sales are made pursuant to long-term, take-or-pay agreements with Cliffs Steel and U.S. Steel, who are two of the largest blast furnace steelmakers in North America. The take-or-pay provisions of our agreements require our customers to purchase all or substantially all of the coke volumes produced as specified in the agreements or pay the contract price for any tonnage they do not purchase. The take-or-pay provisions of our agreements also require us to deliver minimum annual tonnage, which vary by contract, and have historically been approximately 4.1 million tons, covering at least 90 percent of each facility's nameplate capacity. The take-or-pay provisions also require our customers to purchase such volumes of coke or pay the contract price for any tonnage they elect not to take. As a result of the impacts the COVID-19 global pandemic has had on our customers, in July 2020, SunCoke entered into customer agreement amendments, providing near-term coke supply relief for our customers, in exchange for extending certain agreements. Subsequent to these amendments, in October 2020, the contract expiration date of the Haverhill II contract with Cliffs Steel was further extended from June 2023 to June 2025. Our coke sales agreements have approximately 17.6 million tons of unsatisfied or partially unsatisfied performance obligations, which are expected to be delivered over an average remaining contract term of approximately six years. Our coke sales prices include an operating cost component, a coal cost component and a return of capital component. Operating costs under two of our coke sales agreements are contractual, subject to an annual adjustment based on an inflation index. Under our other four coke sales agreements operating costs are passed through to the respective customers subject to an annually negotiated budget, in some cases subject to a cap annually adjusted for inflation, and generally we share any difference in costs from the budgeted amounts with our customers. Our coke sales agreements contain pass-through provisions for coal and coal procurement costs, subject to meeting contractual coal-to-coke yields. To the extent that the actual coal-to-coke yields are less than the contractual standard, we are responsible for the cost of the excess coal used in the cokemaking process. Conversely, to the extent our actual coal-to-coke yields are higher than the contractual standard, we realize gains. The reimbursement of pass-through operating and coal costs from these coke sales agreements are considered to be variable consideration components included in the cokemaking sales price. The return of capital component for each ton of coke sold to the customer is determined at the time the coke sales agreement is signed and is effective for the term of each sales agreement. This component of our coke sales prices is intended to provide an adequate return on invested capital and may differ based on investment levels and other considerations. The actual return on invested capital at any facility is also impacted by favorable or unfavorable performance on pass-through cost items. Revenues are recognized when performance obligations to our customers are satisfied in an amount that reflects the consideration that we expect to receive in exchange for the coke. Logistics In our logistics business, handling and/or mixing services are provided to steel, coke (including some of our domestic cokemaking facilities), electric utility, coal producing and other manufacturing based customers. Materials are transported in numerous ways, including rail, truck, barge or ship. We do not take possession of materials handled, but rather act as intermediaries between our customers and end users, deriving our revenues from services provided on a per ton basis. The handling and mixing services consist primarily of two performance obligations, unloading and loading of materials. Revenues are recognized when the customer receives the benefits of the services provided, in an amount that reflects the consideration that we will receive in exchange for those services. Estimated take-or-pay revenue of approximately $35 million from all of our multi-year logistics contracts is expected to be recognized over the next three years for unsatisfied or partially unsatisfied performance obligations as of December 31, 2020. Energy Our energy sales are made pursuant to either steam or energy supply and purchase agreements or is sold into the regional power market. Our cokemaking ovens utilize efficient, modern heat recovery technology designed to combust the coal’s volatile components liberated during the cokemaking process and use the resulting heat to create steam or electricity for sale. The energy provided under these arrangements results in transfer of control over time. Revenues are recognized over time as energy is delivered to our customers, in an amount based on the terms of each arrangement. Operating and Licensing Fees Operating and licensing fees are made pursuant to long-term contracts with ArcelorMittal Brazil, where we operate a Brazilian cokemaking facility. The licensing fees are based upon the level of production required by our customer as well as a fixed annual fee. Operating fees include the full pass-through of the operating costs of the Brazilian facility as well as a per ton fee based on the level of production required by our customer. Revenues are recognized over time as our customers receive and consume the benefits in an amount that corresponds directly with the value provided to the customer to date. Disaggregated Sales and Other Operating Revenue The following table provides disaggregated sales and other operating revenue by product or service, excluding intersegment revenues: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Sales and other operating revenue: Cokemaking $ 1,218.9 $ 1,434.9 $ 1,250.5 Energy 43.6 51.1 49.7 Logistics 35.5 72.1 101.0 Operating and licensing fees 31.6 38.4 40.4 Other 3.4 3.8 9.3 Sales and other operating revenue $ 1,333.0 $ 1,600.3 $ 1,450.9 Disaggregated sales and other operating revenue by customer is discussed in Note 4.

Business Segment Information

Business Segment Information	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Business Segment Information	20. Business Segment Information The Company reports its business through three segments: Domestic Coke, Brazil Coke and Logistics. The Domestic Coke segment includes the Jewell, Indiana Harbor, Haverhill, Granite City and Middletown cokemaking facilities. Each of these facilities produces coke, and all facilities except Jewell recover waste heat, which is converted to steam or electricity through a similar production process. The Brazil Coke segment includes the licensing and operating fees payable to us under long-term contracts with ArcelorMittal Brazil, under which we operate a cokemaking facility located in Vitória, Brazil through at least 2023. Logistics operations are comprised of CMT, KRT, Lake Terminal, which provides services to our Indiana Harbor cokemaking facility, and DRT, which provides services to our Jewell cokemaking facility. Handling and mixing results are presented in the Logistics segment. Corporate expenses that can be identified with a segment have been included in determining segment results. The remainder is included in Corporate and Other. Corporate and Other also includes activity from our legacy coal mining business. Segment assets are those assets utilized within a specific segment and exclude taxes. The following table includes Adjusted EBITDA, which is the measure of segment profit or loss reported to the chief operating decision maker for purposes of allocating resources to the segments and assessing their performance: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Sales and other operating revenue: Domestic Coke $ 1,265.4 $ 1,489.1 $ 1,308.3 Brazil Coke 31.6 38.4 40.4 Logistics 36.0 72.8 102.2 Logistics intersegment sales 22.1 26.3 24.5 Elimination of intersegment sales (22.1) (26.3) (24.5) Total sales and other operating revenue $ 1,333.0 $ 1,600.3 $ 1,450.9 Adjusted EBITDA: Domestic Coke $ 217.0 $ 226.7 $ 207.9 Brazil Coke 13.5 16.0 18.4 Logistics 17.3 42.6 72.6 Corporate and Other (1) (41.9) (37.4) (35.7) Total Adjusted EBITDA $ 205.9 $ 247.9 $ 263.2 Depreciation and amortization expense: Domestic Coke $ 119.1 $ 120.5 $ 114.4 Brazil Coke 0.5 0.6 0.7 Logistics 12.8 21.4 25.1 Corporate and Other 1.3 1.3 1.4 Total depreciation and amortization expense $ 133.7 $ 143.8 $ 141.6 Capital expenditures: Domestic Coke $ 60.0 $ 105.2 $ 94.9 Brazil Coke 0.4 0.3 0.2 Logistics 13.5 4.6 5.2 Total capital expenditures $ 73.9 $ 110.1 $ 100.3 (1) Corporate and Other includes the activity from our legacy coal mining business, which incurred Adjusted EBITDA losses of $13.2 million, $11.2 million, and $9.8 million for the years ended December 31, 2020, 2019 and 2018, respectively. Additionally, Corporate and Other includes foundry related research and development costs of $3.9 million during 2020. The following table sets forth the Company’s segment assets: December 31, 2020 2019 (Dollars in millions) Segment assets: Domestic Coke $ 1,358.9 $ 1,434.2 Brazil Coke 17.7 14.6 Logistics 199.5 200.8 Corporate and Other 31.8 102.0 Segment assets, excluding income tax receivable 1,607.9 1,751.6 Tax receivable 5.5 2.2 Total assets $ 1,613.4 $ 1,753.8 The Company evaluates the performance of its segments based on segment Adjusted EBITDA, which is defined as earnings before interest, taxes, depreciation and amortization (“EBITDA”), adjusted for any impairments, (gain) loss on extinguishment of debt, changes to our contingent consideration liability related to our acquisition of CMT, loss on the disposal of our interest in VISA SunCoke and/or transaction costs incurred as part of the Simplification Transaction. EBITDA and Adjusted EBITDA do not represent and should not be considered alternatives to net income under GAAP and may not be comparable to other similarly titled measures in other businesses. Management believes Adjusted EBITDA is an important measure in assessing operating performance. Adjusted EBITDA provides useful information to investors because it highlights trends in our business that may not otherwise be apparent when relying solely on GAAP measures and because it eliminates items that have less bearing on our operating performance. EBITDA and Adjusted EBITDA are not measures calculated in accordance with GAAP, and they should not be considered a substitute for net income, or any other measure of financial performance presented in accordance with GAAP. Additionally, other companies may calculate Adjusted EBITDA differently than we do, limiting its usefulness as a comparative measure. Below is the reconciliation of Adjusted EBITDA to net income (loss), which is its most directly comparable financial measure calculated and presented in accordance with GAAP: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Net income (loss) attributable to SunCoke Energy, Inc. $ 3.7 $ (152.3) $ 26.2 Add: Net income attributable to noncontrolling interests 5.1 3.9 20.8 Net income (loss) $ 8.8 $ (148.4) $ 47.0 Add: Long-lived asset and goodwill impairment — 247.4 — Depreciation and amortization expense 133.7 143.8 141.6 Interest expense, net 56.3 60.3 61.4 (Gain) loss on extinguishment of debt, net (5.7) (1.5) 0.3 Income tax expense (benefit) 10.3 (54.7) 4.6 Contingent consideration adjustments (1) — (4.2) 2.5 Restructuring costs (2) 2.5 — — Simplification Transaction costs (3) — 5.2 0.4 Loss from equity method investment — — 5.4 Adjusted EBITDA $ 205.9 $ 247.9 $ 263.2 Subtract: Adjusted EBITDA attributable to noncontrolling interests (4) 9.1 40.7 82.0 Adjusted EBITDA attributable to SunCoke Energy, Inc. $ 196.8 $ 207.2 $ 181.2 (1) In connection with the CMT acquisition, the Company entered into a contingent consideration arrangement that requires the Company to make future payments to the seller based on future volume over a specified threshold, price and contract renewals. Adjustments to the fair value of the contingent consideration were primarily the result of modifications to the volume forecast. This liability was written to zero during the third quarter of 2019, and the related contract was terminated in 2020. See Note 18. (2) Charges related to a company-wide restructuring and cost-reduction initiative. (3) Costs expensed primarily by the Partnership associated with the Simplification Transaction.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual amounts could differ from these estimates.
Revenue Recognition	Revenue RecognitionThe Company sells coke as well as steam and electricity and also provides mixing and/or handling services of coal and other aggregates. The Company also receives fees for operating the cokemaking plant in Brazil and for the licensing of its proprietary technology for use at this facility as well as reimbursement of substantially all of its operating costs. See Note 19.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with a remaining maturity of three months or less at the time of purchase to be cash equivalents. These cash equivalents consist principally of money market funds.
Inventories	Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method, except for the Company’s materials and supplies inventory, which are determined using the average-cost method. The Company primarily utilizes the selling prices under its long-term coke supply contracts to record lower of cost or net realizable value inventory adjustments.
Properties, Plants and Equipment	Properties, Plants and Equipment Plants and equipment are depreciated on a straight-line basis over their estimated useful lives. Coke and energy plant, machinery and equipment are generally depreciated over 25 to 30 years. Logistics plant and equipment are generally depreciated over 15 to 35 years. Depreciation and amortization is excluded from cost of products sold and operating expenses and is presented separately on the Consolidated Statements of Operations. Gains and losses on the disposal or retirement of fixed assets are reflected in earnings when the assets are sold or retired. Amounts incurred that extend an asset’s useful life, increase its productivity or add production capacity are capitalized. The Company accounts for changes in useful lives, when appropriate, as a change in estimate, with prospective application only. The Company capitalized interest of $0.2 million, $2.3 million, and $3.2 million in 2020, 2019 and 2018, respectively. Direct costs, such as outside labor, materials, internal payroll and benefits costs incurred during capital projects are capitalized; indirect costs are not capitalized. Normal repairs and maintenance costs are expensed as incurred.
Goodwill	GoodwillGoodwill, which represents the excess of the purchase price over the fair value of net assets acquired, is tested for impairment as of October 1 of each year, or when events occur or circumstances change that would, more likely than not, reduce the fair value of a reporting unit to below its carrying value. The Company performs its annual goodwill impairment test by comparing the fair value of the reporting unit with its carrying amount. The Company would recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value.
Intangible Assets	Intangible AssetsIntangible assets are primarily comprised of permits. Intangible assets are amortized over their useful lives in a manner that reflects the pattern in which the economic benefit of the intangible asset is consumed. Intangible assets are assessed for impairment when a triggering event occurs.
Impairment of Long-Lived Assets	Impairment of Long-Lived AssetsLong-lived assets, which includes intangible assets and properties, plants and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. A long-lived asset, or group of assets, is considered to be impaired when the undiscounted net cash flows expected to be generated by the asset are less than its carrying amount. Such estimated future cash flows are highly subjective and are based on numerous assumptions about future operations and market conditions. The impairment recognized is the amount by which the carrying amount exceeds the fair market value of the impaired asset, or group of assets. It is also difficult to precisely estimate fair market value because quoted market prices for our long-lived assets may not be readily available. Therefore, fair market value is generally based on the present values of estimated future cash flows using discount rates commensurate with the risks associated with the assets being reviewed for impairment.
Income Taxes	Income Taxes Deferred tax asset and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those differences are projected to be recovered or settled. The Company recognizes uncertain tax positions in its financial statements when minimum recognition threshold and measurement attributes are met in accordance with current accounting guidance.
Black Lung Benefit Liabilities	Black Lung Benefit LiabilitiesThe Company has obligations related to coal workers’ pneumoconiosis, or black lung, benefits of certain of our former coal miners and their dependents. We adjust our liability each year based upon actuarial calculations of our expected future payments for these benefits, including a provision for incurred but not reported losses.
Postretirement Benefit Plan Liabilities	Postretirement Benefit Plan LiabilitiesThe postretirement benefit plans, which are frozen, are unfunded and the accumulated postretirement benefit obligation is fully recognized on the Consolidated Balance Sheets. Actuarial gains (losses) and prior service costs (benefits) which have not yet been recognized in net income are recognized as a credit (charge) to accumulated other comprehensive income (loss). The credit (charge) to accumulated other comprehensive income (loss), which is reflected net of related tax effects, is subsequently recognized in net income when amortized as a component of postretirement benefit plans expense included in interest expense, net on the Consolidated Statements of Operations.
Asset Retirement Obligations	Asset Retirement ObligationsThe fair value of a liability for an asset retirement obligation is recognized in the period in which it is incurred if a reasonable estimate of fair value can be made. The associated asset retirement costs are capitalized as part of the carrying amount of the asset and depreciated over its remaining estimated useful life. When the assumptions used to estimate a recorded asset retirement obligation change, a revision is recorded to both the asset retirement obligation and the asset retirement cost capitalized to the extent remaining useful life exists. The Company’s asset retirement obligations primarily relate to costs associated with restoring land to its original state.
Shipping and Handling Costs	Shipping and Handling Costs Shipping and handling costs are included in cost of products sold and operating expenses on the Consolidated Statements of Operations and are generally passed through to our customers. The Company has elected the practical expedient under Accounting Standards Codification ("ASC") 606, "Revenue from Contracts with Customers," to account for shipping and handling activities as a promise to fulfill the transfer of coke.
Share-based Compensation	Share-Based CompensationWe measure the cost of employee services in exchange for equity instrument awards and cash awards based on the grant-date fair value of the award. Cash awards and the performance metrics of equity awards are remeasured on a quarterly basis. The market metrics of equity awards are not remeasured. The total cost is recognized over the requisite service period. Award forfeitures are accounted for as they occur. The costs of equity awards and cash awards are recorded to additional paid-in capital and accrued liabilities, respectively, on the Consolidated Balance Sheets.
Fair Value Measurements	Fair Value MeasurementsThe Company determines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As required, the Company utilizes valuation techniques that maximize the use of observable inputs (levels 1 and 2) and minimize the use of unobservable inputs (level 3) within the fair value hierarchy included in current accounting guidance. Assets and liabilities are classified within the fair value hierarchy based on the lowest level (least observable) input that is significant to the measurement in its entirety.
Currency Transactions	Currency TranslationThe functional currency of the Company’s Brazilian operations is the Brazilian real. The Company’s Brazil operations translate its assets and liabilities into U.S. dollars at the current exchange rates in effect at the end of the fiscal period. The gains or losses that result from this process are shown as cumulative translation adjustments within accumulated other comprehensive loss in the Consolidated Balance Sheets. The revenue and expense accounts of foreign operations are translated into U.S. dollars at the average exchange rates during the period.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, “Leases (Topic 842).” ASU 2016-02 requires leases to be recognized as assets and liabilities on the balance sheet for the rights and obligations created by all leases with terms of more than 12 months. Subsequently, the FASB has issued various ASUs to provide further clarification around certain aspects of ASC 842, “Leases.” We adopted the standard effective January 1, 2019 using the modified retrospective transition approach and elected not to adjust prior comparative periods. Upon adoption, the Company recognized right-of-use assets and lease liabilities of $5.1 million at January 1, 2019. See Note 14. In February 2018, the FASB issued ASU 2018-02, “Income Statement-Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” The Company adopted this ASU in the first quarter 2018 and reclassified $1.1 million of deferred tax adjustments to accumulated other comprehensive income (loss) from retained earnings on the December 31, 2017 balance sheet for the tax effects resulting from the Tax Cuts and Jobs Act of 2017.

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	12 Months Ended
	Dec. 31, 2020
Noncontrolling Interest [Abstract]
Schedule of Changes in Ownership Interest	The following table summarizes the non-cash (decreases) increases on our balance sheet related to the Simplification Transaction, reflecting the changes in ownership of the Partnership and a step-up in the tax basis in the underlying assets acquired: (Dollars in millions) Noncontrolling interest $ (182.5) Deferred income taxes $ (43.7) Common stock $ 0.3 Additional paid-in capital $ 225.9 The following table summarizes the effects of the changes in the Company's ownership interest in the Partnership on SunCoke's equity in 2019 and 2018. There were no changes in SunCoke's ownership interest in consolidated subsidiaries in 2020. Years Ended December 31, 2019 2018 Net (loss) income attributable to SunCoke Energy, Inc. $ (152.3) $ 26.2 Increase (decrease) in SunCoke Energy, Inc. equity for the purchase of additional interest in the Partnership (1) 182.5 (1.2) Changes from net (loss) income attributable to SunCoke Energy, Inc. and transfers to noncontrolling interest $ 30.2 $ 25.0 (1) During the years ended December 31, 2018 the Company purchased 231,171, of outstanding Partnership common units in the open market for total cash payments of $4.2 million. SunCoke controlled the Partnership both before and after this unit acquisition. Therefore, the cash paid for the Partnership units in excess of the net book value of Partnership interest acquired was recorded as a reduction to additional paid-in capital, reducing SunCoke’s equity balance. Upon the closing of the Simplification Transaction, the Company's program to purchase outstanding Partnership common units was terminated.

Customer Concentrations (Tables

Customer Concentrations (Tables)	12 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Schedules of Concentration of Risk, by Risk Factor	The tables below shows sales to the Company's significant customers: Year Ended December 31, 2020 Sales and other operating revenue Percent of Company sales and other operating revenue (Dollars in millions) Cliffs Steel / AM USA (1)(2) $ 687.3 51.6 % Cliffs Steel / AK Steel (1)(2) $ 355.8 26.7 % U.S. Steel (3) $ 208.2 15.6 % Years Ended December 31, 2019 2018 Sales and other operating revenue Percent of Company sales and other operating revenue Sales and other operating revenue Percent of Company sales and other operating revenue (Dollars in millions) AM USA (2) $ 786.4 49.1 % $ 695.6 47.9 % AK Steel (2) $ 433.3 27.1 % $ 377.9 26.0 % U.S. Steel (3) $ 255.4 16.0 % $ 206.8 14.3 % (1) Combined sales to Cliffs Steel/AM USA and Cliffs Steel/AK Steel were $1,043.1 million, or 78.3 percent of total Company sales and other operating revenue for the year ended December 31, 2020. (2) Represents revenues included in our Domestic Coke segment. (3) Represents revenues included in our Domestic Coke and Logistics segments.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Components of income before income tax expense	The components of income before income tax expense (benefit) and loss from equity method investment are as follows: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Domestic $ 6.1 $ (218.6) $ 39.3 Foreign 13.0 15.5 17.7 Total $ 19.1 $ (203.1) $ 57.0
Components of income tax expense	Income tax expense (benefit) consisted of the following: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Current tax (benefit) expense: U.S. federal $ (4.7) $ 0.3 $ 1.4 State (0.3) 3.8 2.1 Foreign 3.2 4.3 4.5 Total current tax (benefit) expense (1.8) 8.4 8.0 Deferred tax expense (benefit): U.S. federal 3.6 (39.3) (3.1) State 8.5 (23.8) (0.3) Total deferred tax expense (benefit) 12.1 (63.1) (3.4) Total $ 10.3 $ (54.7) $ 4.6
Reconciliation of income tax expense	The reconciliation of income tax expense at the U.S. statutory rate to income tax expense (benefit) is as follows: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Income tax expense (benefit) at U.S. statutory rate $ 4.0 21.0 % $ (42.7) 21.0 % $ 12.0 21.0 % Increase (reduction) in income taxes resulting from: Income attributable to noncontrolling interests in partnerships (1) (1.1) (5.6) % (0.6) 0.3 % (3.9) (6.8) % State and other income taxes, net of federal income tax effects (2) 7.8 41.2 % (15.0) 7.4 % 1.6 2.8 % Impact of CARES Act (3) (1.5) (7.9) % — — % — — % Logistics goodwill impairment — — % 3.3 (1.7) % — — % Impact of Tax Legislation (4) — — % — — % (4.8) (8.4) % Return to provision adjustments 1.2 6.5 % (0.8) 0.4 % — — % Change in valuation allowance (1.3) (6.9) % 0.6 (0.3) % 0.7 1.2 % Other 1.2 6.0 % 0.5 (0.2) % (1.0) (1.8) % Income tax expense (benefit) at effective tax rate $ 10.3 54.3 % $ (54.7) 26.9 % $ 4.6 8.0 % (1) No income tax expense is reflected in the Consolidated Statements of Operations for income attributable to noncontrolling interests in our Indiana Harbor cokemaking facility or the Partnership prior to the Simplification Transaction discussed in Note 3. (2) A change in the tax filing status of our Convent Marine Terminal in Louisiana from a taxable partnership to a member of the consolidated return group resulted in lower apportioned state tax rates and the revaluation of certain deferred tax assets, which resulted in $6.5 million of deferred income tax expense in 2020. (3) On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security ("CARES Act") was enacted. The enactment of the CARES Act allows the Company to carry back net operating losses generated in 2019 to each of the five years preceding 2019. As a result of the CARES Act, SunCoke expects to receive tax refunds of approximately $4.8 million for prior year taxes paid and recorded a tax benefit of $1.5 million during 2020. (4) On December 22, 2017, the Tax Cuts and Jobs Act ("Tax Legislation") was enacted. The Tax Legislation significantly revised the U.S. corporate income tax structure, including lowering corporate income tax rates. In addition, the SEC staff released Staff Accounting Bulletin 118 on December 23, 2017, which provided for companies to record a provisional impact of the Tax Legislation during a measurement period, not to exceed one year, in situations where companies do not have the necessary information available, prepared, or analyzed in
Tax effects of temporary differences that comprise the net deferred income tax liability	The tax effects of temporary differences that comprise the net deferred income tax liability from operations are as follows: December 31, 2020 2019 (Dollars in millions) Deferred tax assets: Retirement benefit liabilities $ 6.3 $ 6.4 Black lung benefit liabilities 14.8 12.8 Share-based compensation 4.2 4.7 Federal tax credit carryforward (1) 19.9 20.5 Foreign tax credit carryforward (2) 19.4 14.4 Federal net operating loss (3) 5.3 1.6 Section 163j interest limitation carryforward (4) — 5.7 State tax credit carryforward, net of federal income tax effects (5) 0.3 1.1 State net operating loss carryforward, net of federal income tax effects (6) 12.9 13.6 Other liabilities not yet deductible 11.5 4.4 Total deferred tax assets 94.6 85.2 Less: valuation allowance (7) (19.6) (20.9) Deferred tax asset, net 75.0 64.3 Deferred tax liabilities: Properties, plants and equipment (152.9) (17.9) Investment in partnerships (81.4) (194.0) Total deferred tax liabilities (234.3) (211.9) Net deferred tax liability $ (159.3) $ (147.6) (1) Federal tax credit carryforward expires in 2032 through 2034. (2) Foreign tax credit carryforward expires in 2024 through 2030. (3) Federal net operating loss does not expire. (4) The Tax Legislation generally limits the deductibility of business interest expense to 30 percent (50 percent as a result of CARES Act) of adjusted taxable income. This limitation resulted in a deferred tax asset in 2019 as the interest expense in excess of the limitation is eligible for deduction in future taxable years and has no expiration. In 2020, SunCoke applied the final regulations on section 163(j) released by the IRS on July 28, 2020, which resulted in no interest limitation for the year. (5) State tax credit carryforward, net of federal income tax effects expires in 2021 through 2022. (6) State net operating loss carryforward, net of federal income tax effects expires in 2023 through 2037.

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2020
Inventory Disclosure [Abstract]
Components of inventories	These components of inventories were as follows: December 31, 2020 2019 (Dollars in millions) Coal $ 60.6 $ 94.4 Coke 21.1 8.1 Materials, supplies and other 44.9 44.5 Total inventories $ 126.6 $ 147.0

Properties, Plants and Equipmen

Properties, Plants and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Components of net properties, plants and equipment	The components of net properties, plants and equipment were as follows: December 31, 2020 2019 (Dollars in millions) Coke and energy plant, machinery and equipment $ 2,009.3 $ 1,968.2 Logistics plant, machinery and equipment 157.3 147.9 Land and land improvements 104.5 106.0 Construction-in-progress 47.4 29.5 Other 42.4 42.3 Gross investment, at cost 2,360.9 2,293.9 Less: accumulated depreciation (1,032.9) (903.7) Total properties, plants and equipment, net $ 1,328.0 $ 1,390.2

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Domestic Coke Logistics Total (Dollars in millions) Net balances at December 31, 2018 $ 3.4 $ 73.5 $ 76.9 Impairment — (73.5) (73.5) Net balances at December 31, 2019 and 2020 $ 3.4 $ — $ 3.4
Schedule of Finite-Lived Intangible Assets	The components of other intangible assets, net, excluding fully amortized intangible assets, were as follows: December 31, 2020 December 31, 2019 Weighted - Average Remaining Amortization Years Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net (Dollars in millions) Customer contracts — $ — $ — $ — $ 7.7 $ 7.2 $ 0.5 Customer relationships 4 6.7 4.5 2.2 6.7 3.9 2.8 Permits 22 31.7 1.7 30.0 31.7 0.3 31.4 Other 30 1.6 — 1.6 — — — Total $ 40.0 $ 6.2 $ 33.8 $ 46.1 $ 11.4 $ 34.7
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Based on the carrying value of finite-lived intangible assets as of December 31, 2020, we estimate amortization expense for each of the next five years as follows: (Dollars in millions) 2021 $ 2.0 2022 2.0 2023 2.0 2024 1.9 2025 1.5 Thereafter 24.4 Total $ 33.8

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2020
Asset Retirement Obligation [Abstract]
Reconciliation of changes in the asset retirement obligation	The following table provides a reconciliation of changes in the asset retirement obligation from operations during each period: Years ended December 31, 2020 2019 Asset retirement obligation at beginning of year $ 15.3 $ 14.6 Liabilities settled (0.1) (1.2) Accretion expense (1) 1.1 1.0 Revisions in estimated cash flows (2) (4.9) 0.9 Asset retirement obligation at end of year (3) $ 11.4 $ 15.3 (1) Included in cost of products sold and operating expenses on the Consolidated Statements of Operations. (2) Revisions of estimated cash flows in 2020 were primarily due to the identification of more cost efficient demolition methods as well as the timing of projected spending on certain obligations.

Retirement Benefits Plans (Tabl

Retirement Benefits Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Postretirement benefit plans (benefit) expense	Postretirement benefit plans expense consisted of the following components: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Interest cost on benefit obligations $ 0.7 $ 1.1 $ 1.0 Amortization of: Actuarial losses 0.7 0.6 0.6 Prior service benefit (0.5) (0.6) (0.7) Total expense $ 0.9 $ 1.1 $ 0.9
Discount rates used to determine benefit obligations for the plans	The following assumptions were used to determine postretirement benefit plans expense: December 31, 2020 2019 2018 Discount rate 2.90 % 4.00 % 3.35 % December 31, 2020 2019 Discount rate 2.00 % 2.90 %
Recognized components of other comprehensive income (loss)	The following amounts were recognized as components of other comprehensive income (loss) before related tax impacts: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Reclassifications to earnings of: Actuarial loss amortization $ 0.7 $ 0.6 $ 0.6 Prior service benefit amortization (0.5) (0.6) (0.7) Retirement benefit plan funded status Actuarial (losses) gains (2.0) (1.0) 0.8 $ (1.8) $ (1.0) $ 0.7
Components of changes in benefit obligations and fair value of plan assets	The following table sets forth the components of the changes in benefit obligations: Years Ended December 31, 2020 2019 (Dollars in millions) Benefit obligation at beginning of year $ 27.4 $ 28.2 Interest cost 0.7 1.1 Actuarial loss 2.0 1.0 Benefits paid (2.6) (2.9) Benefit obligation at end of year (1) $ 27.5 $ 27.4 (1) The current portion of retirement benefit liabilities, which totaled $2.8 million and $2.9 million at December 31, 2020 and 2019, respectively, is classified in accrued liabilities on the Consolidated Balance Sheets.
Cumulative amounts not recognized	The following table sets forth the cumulative amounts not yet recognized in net (loss) income: Years Ended December 31, 2020 2019 (Dollars in millions) Cumulative amounts not yet recognized in net (loss) income: Actuarial losses $ 12.1 $ 10.8 Prior service benefits (1.5) (2.0) Accumulated other comprehensive loss (before related tax benefit) $ 10.6 $ 8.8
Expected benefit payments	The expected benefit payments through 2030 for the postretirement benefit plan are as follows: (Dollars in millions) Year ending December 31: 2021 $ 2.8 2022 $ 2.6 2023 $ 2.4 2024 $ 2.2 2025 $ 2.0 2026 through 2030 $ 8.1

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consist of following: December 31, 2020 2019 (Dollars in millions) Accrued benefits $ 18.3 $ 21.7 Current portion of postretirement benefit obligation 2.8 2.9 Other taxes payable 9.8 9.9 Current portion of black lung liability 4.6 4.6 Accrued legal 6.4 2.7 Other 7.9 5.5 Total accrued liabilities $ 49.8 $ 47.3

Debt and Financing Obligations

Debt and Financing Obligations (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Total debt and financing obligations consisted of the following: December 31, 2020 2019 (Dollars in millions) 7.50 percent senior notes, due 2025 ("2025 Senior Notes") $ 587.3 $ 650.0 $400.0 revolving credit facility, due 2024 ("Revolving Facility") 88.3 143.3 5.35 percent financing obligation, due 2024 14.9 7.2 Total borrowings $ 690.5 $ 800.5 Original issue discount (3.3) (4.3) Debt issuance costs (10.3) (13.3) Total debt and financing obligation $ 676.9 $ 782.9 Less: current portion of long-term debt and financing obligation 3.0 2.9 Total long-term debt and financing obligation $ 673.9 $ 780.0
Schedule of Maturities of Long-term Debt	As of December 31, 2020, the combined aggregate amount of maturities for long-term borrowings for each of the next five years is as follows: (Dollars in millions) 2021 $ 3.0 2022 3.2 2023 3.3 2024 93.7 2025 587.3 2026-Thereafter — Total $ 690.5

Commitments And Contingent Li_2

Commitments And Contingent Liabilities (Tables)	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of black lung benefit liabilities	The following table summarizes discount rates utilized, active claims and the total black lung liabilities: December 31, 2020 2019 Discount rate (1) 2.0 % 2.9 % Active claims 309 324 Total black lung liability (dollars in millions) (2) $ 64.6 $ 55.1 (1) The discount rate is determined based on a portfolio of high-quality corporate bonds with maturities that are consistent with the estimated duration of our black lung obligations. A decrease of 25 basis points in the discount rate would have increased black lung expense by $1.6 million in 2020. (2) The current portion of the black lung liability was $4.6 million at both December 31, 2020 and 2019, respectively, and was included in accrued liabilities on the Consolidated Balance Sheets. The following table summarizes annual black lung payments and expense: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Payments $ 6.0 $ 5.2 $ 6.3 Expense (1) $ 15.4 $ 10.9 $ 5.4 (1) Expenses incurred in excess of annual accretion of the black lung liability primarily reflect the impact of changes in discount rates as well as increases in expected future claims as a result of higher refiling and approval rate assumptions.

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lease Expense and Weighted Average Remaining Lease Term and Weighted Average Discount Rate	The components of lease expense were as follows: Year ended December 31, 2020 Year ended December 31, 2019 (Dollars in millions) Operating leases: Cost of products sold and operating expenses $ 1.8 $ 1.9 Selling, general and administrative expenses 0.5 0.5 $ 2.3 $ 2.4 Short-term leases: Cost of products sold and operating expenses (1)(2) 6.4 9.3 Total lease expense $ 8.7 $ 11.7 (1) Includes expenses for month-to-month equipment leases, which are classified as short-term as the Company is not reasonably certain to renew the lease term beyond one month. (2) Includes variable lease expenses, which are immaterial to the consolidated financial statements. The weighted average remaining lease term and weighted average discount rate were as follows: December 31, 2020 December 31, 2019 Weighted average remaining lease term of operating leases 7.3 years 7.9 years Weighted average discount rate of operating leases 4.7 % 4.8 %
Supplemental Balance Sheet and Cash Flow Information	Supplemental balance sheet information related to leases was as follows: Financial Statement Classification December 31, 2020 December 31, 2019 (Dollars in millions) Operating ROU assets Deferred charges and other assets $ 10.8 $ 12.4 Operating lease liabilities: Current operating lease liabilities Accrued liabilities $ 2.0 $ 1.9 Noncurrent operating lease liabilities Other deferred credits and liabilities 8.2 9.8 Total operating lease liabilities $ 10.2 $ 11.7 Supplemental cash flow information related to leases was as follows: Year Ended December 31, 2020 Year Ended December 31, 2019 (Dollars in millions) Operating cash flow information: Cash paid for amounts included in the measurement of operating lease liabilities $ 2.3 $ 3.9 Non-cash activity: ROU assets obtained in exchange for new operating lease liabilities $ 0.2 $ 7.9
Lease Maturity, Operating Lease	Maturities of operating lease liabilities as of December 31, 2020 are as follows: (Dollars in millions) Year ending December 31: 2021 $ 2.3 2022 1.7 2023 1.4 2024 1.3 2025 1.3 2026-Thereafter 4.0 Total lease payments 12.0 Less: imputed interest 1.8 Total lease liabilities $ 10.2

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Components of accumulated other comprehensive (loss) income	The following tables set forth the changes in the balance of accumulated other comprehensive loss, net of tax, by component: Benefit Plans Currency Translation Adjustments Total (Dollars in millions) At December 31, 2018 $ (6.0) $ (7.1) $ (13.1) Other comprehensive loss before reclassifications / adjustments — (0.6) (0.6) Retirement benefit plans funded status adjustment (0.7) — (0.7) Net current period change in accumulated other comprehensive loss (0.7) (0.6) (1.3) At December 31, 2019 $ (6.7) $ (7.7) $ (14.4) Other comprehensive loss before reclassifications / adjustments 0.1 (1.2) (1.1) Retirement benefit plans funded status adjustment (1.6) — (1.6) Net current period change in accumulated other comprehensive loss (1.5) (1.2) (2.7) At December 31, 2020 $ (8.2) $ (8.9) $ (17.1)
Impact of net income of reclassification adjustments	The (decrease) increase in net income due to reclassification adjustments from accumulated other comprehensive income were as follows (1) : December 31, 2020 2019 2018 (Dollars in millions) Recognition of accumulated currency translation loss upon sale of equity method investment in VISA SunCoke $ — $ — $ (9.0) Amortization of benefit plans to net income: (2) Actuarial loss $ (0.6) $ (0.6) $ (0.6) Prior service benefit 0.5 0.6 0.7 Total, net of tax (3) $ (0.1) $ — $ (8.9) (1) Amounts in parentheses indicate debits to net income. (2) These accumulated other comprehensive (income) loss components are included in the computation of postretirement benefit plan expense (benefit) and included in interest expense, net on the Consolidated Statements of Operations. See Note 10.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]
Summary of information with respect to common stock option awards and performance share units	The Company granted the following stock options during the years ended December 31, 2019 and 2018, with an exercise price equal to the closing price of our common stock on the date of grant: Weighted Average Per Share Number of Shares Exercise Price Weighted Average Grant Date Fair Value Traditional stock options: 2019 grant 267,897 $ 9.87 $ 4.09 2018 grant 78,447 $ 10.49 $ 5.38 The following table summarizes information with respect to common stock option awards outstanding as of December 31, 2020 and stock option activity during the fiscal year then ended: Number of Weighted Weighted Average Remaining Contractual Term (years) Aggregate Outstanding at December 31, 2019 3,136,831 $ 15.02 4.3 $ 0.3 Exercised (2,825) $ 3.80 Forfeited (33,146) $ 12.25 Outstanding at December 31, 2020 3,100,860 $ 15.02 3.2 $ 0.1 Exercisable at December 31, 2020 2,733,205 $ 15.69 2.4 $ 0.1 Expected to vest at December 31, 2020 367,655 $ 10.01 7.8 $ — The Company grants performance share units ("PSUs"), which represent the right to receive shares of the Company's common stock, contingent upon the attainment of Company performance and market goals and continued employment. The Company granted the following PSUs during the years ended December 31, 2020, 2019 and 2018: Number of PSUs Fair Value per Unit Grant Date Fair Value (Dollars in millions) 2020 grant (1) 228,248 $ 6.70 $ 1.5 2019 grant (1) 227,378 $ 10.79 $ 2.5 2018 grant (1) 96,389 $ 11.36 $ 1.1 (1) The service period for the 2020, 2019, and 2018 PSUs ends on December 31, 2022, 2021 and 2020, and the awards will vest during the first quarter of 2023, 2022 and 2021, respectively.
Weighted-average assumptions	The weighted-average fair value of employee stock options granted during the years ended December 31, 2019 and 2018 was based on using the following weighted-average assumptions: 2019 2018 Risk free interest rate 2 % 3 % Expected term 6 years 6 years Volatility 53 % 52 % Dividend yield 2 % — %
Summary of information with respect to RSUs	The Company granted the following restricted stock units ("RSUs") during the years ended December 31, 2020, 2019 and 2018: Number of RSUs Weighted Average Grant-Date Fair Value per Unit Grant Date Fair Value (Dollars in millions) 2020 grants 304,332 $ 6.04 $ 1.8 2019 grants 136,425 $ 9.87 $ 1.3 2018 grants 32,128 $ 10.49 $ 0.3 The following table summarizes information with respect to RSUs outstanding as of December 31, 2020 and RSU activity during the fiscal year then ended: Number of Weighted Nonvested at December 31, 2019 165,384 $ 9.95 Granted 304,332 $ 6.04 Vested (63,729) $ 9.97 Forfeited — $ — Nonvested at December 31, 2020 405,987 $ 7.02
Summary of information with respect to PSUs	The following table summarizes information with respect to unearned PSUs outstanding as of December 31, 2020 and PSU activity during the fiscal year then ended: Number of Weighted Nonvested at December 31, 2019 575,363 $ 11.20 Granted 228,248 $ 6.70 Vested (92,992) $ 11.40 Forfeited (25,316) $ 11.40 Nonvested at December 31, 2020 685,303 $ 9.76
Schedule of unrecognized compensation cost	Below is a summary of the compensation expense, unrecognized compensation costs, the period for which the unrecognized compensation cost is expected to be recognized over and the estimated forfeiture rate for each award: Years Ended December 31, 2020 2019 2018 2020 2019 2018 December 31, 2020 Compensation Expense (1) Net of tax Unrecognized Compensation Cost Recognition Period (Dollars in millions) (Dollars in millions) (Years) Equity Awards: Stock Options $ 0.3 $ 1.1 $ 0.5 $ 0.3 $ 0.9 $ 0.4 $ 0.1 1.1 RSUs 1.9 1.0 0.4 1.5 0.9 0.3 $ 0.5 1.9 PSUs 1.5 2.2 1.9 1.2 1.8 1.7 $ 1.5 1.5 Total equity awards $ 3.7 $ 4.3 $ 2.8 $ 3.0 $ 3.6 $ 2.4 Liability Awards: Cash RSUs $ 0.8 $ 0.9 $ 0.8 $ 0.6 $ 0.7 $ 0.6 $ 0.6 1.9 Cash incentive award 0.6 0.4 0.9 0.4 0.3 0.7 $ 1.2 1.9 Total liability awards $ 1.4 $ 1.3 $ 1.7 $ 1.0 $ 1.0 $ 1.3 (1) Compensation expense is recognized by the Company in selling, general and administrative expenses on the Consolidated Statements of Operations.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Reconciliation of the weighted-average number of common shares used to compute basic earnings per share ("EPS") to those used to compute diluted EPS	The following table sets forth the reconciliation of the weighted-average number of common shares used to compute basic earnings per share to those used to compute diluted EPS: Years Ended December 31, 2020 2019 2018 (Shares in millions) Weighted-average number of common shares outstanding-basic 83.0 76.8 64.7 Add: effect of dilutive share-based compensation awards 0.2 — 0.8 Weighted-average number of shares-diluted 83.2 76.8 65.5
Schedule of antidilutive securities excluded from computation of earnings per share	The following table shows stock options, restricted stock units, and performance stock units that are excluded from the computation of diluted earnings per share as the shares would have been anti-dilutive: Years Ended December 31, 2020 2019 2018 (Shares in millions) Stock options 3.2 3.0 2.7 Restricted stock units 0.2 0.1 — Performance stock units 0.3 0.4 0.1 Total 3.7 3.5 2.8

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table provides disaggregated sales and other operating revenue by product or service, excluding intersegment revenues: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Sales and other operating revenue: Cokemaking $ 1,218.9 $ 1,434.9 $ 1,250.5 Energy 43.6 51.1 49.7 Logistics 35.5 72.1 101.0 Operating and licensing fees 31.6 38.4 40.4 Other 3.4 3.8 9.3 Sales and other operating revenue $ 1,333.0 $ 1,600.3 $ 1,450.9

Business Segment Information (T

Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Business segment information	The following table includes Adjusted EBITDA, which is the measure of segment profit or loss reported to the chief operating decision maker for purposes of allocating resources to the segments and assessing their performance: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Sales and other operating revenue: Domestic Coke $ 1,265.4 $ 1,489.1 $ 1,308.3 Brazil Coke 31.6 38.4 40.4 Logistics 36.0 72.8 102.2 Logistics intersegment sales 22.1 26.3 24.5 Elimination of intersegment sales (22.1) (26.3) (24.5) Total sales and other operating revenue $ 1,333.0 $ 1,600.3 $ 1,450.9 Adjusted EBITDA: Domestic Coke $ 217.0 $ 226.7 $ 207.9 Brazil Coke 13.5 16.0 18.4 Logistics 17.3 42.6 72.6 Corporate and Other (1) (41.9) (37.4) (35.7) Total Adjusted EBITDA $ 205.9 $ 247.9 $ 263.2 Depreciation and amortization expense: Domestic Coke $ 119.1 $ 120.5 $ 114.4 Brazil Coke 0.5 0.6 0.7 Logistics 12.8 21.4 25.1 Corporate and Other 1.3 1.3 1.4 Total depreciation and amortization expense $ 133.7 $ 143.8 $ 141.6 Capital expenditures: Domestic Coke $ 60.0 $ 105.2 $ 94.9 Brazil Coke 0.4 0.3 0.2 Logistics 13.5 4.6 5.2 Total capital expenditures $ 73.9 $ 110.1 $ 100.3 (1) Corporate and Other includes the activity from our legacy coal mining business, which incurred Adjusted EBITDA losses of $13.2 million, $11.2 million, and $9.8 million for the years ended December 31, 2020, 2019 and 2018, respectively. Additionally, Corporate and Other includes foundry related research and development costs of $3.9 million during 2020. The following table sets forth the Company’s segment assets: December 31, 2020 2019 (Dollars in millions) Segment assets: Domestic Coke $ 1,358.9 $ 1,434.2 Brazil Coke 17.7 14.6 Logistics 199.5 200.8 Corporate and Other 31.8 102.0 Segment assets, excluding income tax receivable 1,607.9 1,751.6 Tax receivable 5.5 2.2 Total assets $ 1,613.4 $ 1,753.8
Reconciliation of Adjusted EBITDA (unaudited) to net income	Below is the reconciliation of Adjusted EBITDA to net income (loss), which is its most directly comparable financial measure calculated and presented in accordance with GAAP: Years Ended December 31, 2020 2019 2018 (Dollars in millions) Net income (loss) attributable to SunCoke Energy, Inc. $ 3.7 $ (152.3) $ 26.2 Add: Net income attributable to noncontrolling interests 5.1 3.9 20.8 Net income (loss) $ 8.8 $ (148.4) $ 47.0 Add: Long-lived asset and goodwill impairment — 247.4 — Depreciation and amortization expense 133.7 143.8 141.6 Interest expense, net 56.3 60.3 61.4 (Gain) loss on extinguishment of debt, net (5.7) (1.5) 0.3 Income tax expense (benefit) 10.3 (54.7) 4.6 Contingent consideration adjustments (1) — (4.2) 2.5 Restructuring costs (2) 2.5 — — Simplification Transaction costs (3) — 5.2 0.4 Loss from equity method investment — — 5.4 Adjusted EBITDA $ 205.9 $ 247.9 $ 263.2 Subtract: Adjusted EBITDA attributable to noncontrolling interests (4) 9.1 40.7 82.0 Adjusted EBITDA attributable to SunCoke Energy, Inc. $ 196.8 $ 207.2 $ 181.2 (1) In connection with the CMT acquisition, the Company entered into a contingent consideration arrangement that requires the Company to make future payments to the seller based on future volume over a specified threshold, price and contract renewals. Adjustments to the fair value of the contingent consideration were primarily the result of modifications to the volume forecast. This liability was written to zero during the third quarter of 2019, and the related contract was terminated in 2020. See Note 18. (2) Charges related to a company-wide restructuring and cost-reduction initiative. (3) Costs expensed primarily by the Partnership associated with the Simplification Transaction.

General and Basis of Presenta_2

General and Basis of Presentation (Details)	12 Months Ended
	Dec. 31, 2020Cokemaking_facilityT
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Coke production experience, more than	60 years
Period that Suncoke constructed the only greenfield cokemaking facilities in the US	30 years
Indiana Harbor
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Ownership percentage (as a percent)	14.80%
United States
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Number of facilities | Cokemaking_facility	5
Cokemaking capacity (in tons)	4,200,000
Brazil
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Number of facilities | Cokemaking_facility	1
Cokemaking capacity (in tons)	1,700,000
Convent, Louisiana, East Chicago, Indiana, West Virginia
Results of Operations for Oil and Gas Producing Activities, by Geographic Area [Line Items]
Coal handling capacity (in tons), more than	40,000,000
Coal storage capacity (in tons)	3,000,000

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)Employee	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Property, Plant and Equipment
Interest costs capitalized | $	$ 0.2	$ 2.3	$ 3.2
Labor Concentrations
Number of employees	841
Percentage of domestic employees	3.00%
Brazil
Labor Concentrations
Number of employees	292
Cokemaking Operations
Labor Concentrations
Number of employees	0.41
Coke and energy plant, machinery and equipment | Minimum
Property, Plant and Equipment
Useful life	25 years
Coke and energy plant, machinery and equipment | Maximum
Property, Plant and Equipment
Useful life	30 years
Logistics plant, machinery and equipment | Minimum
Property, Plant and Equipment
Useful life	15 years
Logistics plant, machinery and equipment | Maximum
Property, Plant and Equipment
Useful life	35 years

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Accounting Pronouncements (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating ROU assets		$ 10.8	$ 12.4
Total lease liabilities		$ 10.2	$ 11.7
AS 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating ROU assets				$ 5.1
Total lease liabilities				$ 5.1
ASU 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax adjustments	$ 1.1

Acquisitions and Divestitures_2

Acquisitions and Divestitures (Simplification Transaction Narrative) (Details) - USD ($)	Jun. 28, 2019	Jun. 27, 2019	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Simplification Transaction
Subsidiary, Sale of Stock [Line Items]
Outstanding Partnership public units (in shares)	17,727,249
Units purchased (in shares)	24,818,149
Quarterly distribution of newly issued shares (in shares)	635,502
Gain (loss) from transaction				$ 0
Transaction costs			$ 11,000,000		$ 4,900,000	$ 400,000
Legal and consulting costs					300,000
Simplification Transaction | Additional Paid-In Capital
Subsidiary, Sale of Stock [Line Items]
Accrued Simplification Transaction costs			$ 5,400,000		$ 5,400,000
Suncoke Inc
Subsidiary, Sale of Stock [Line Items]
Ownership interest of general partnership		60.40%
Interest in partnership		2.00%
Public Unitholders
Subsidiary, Sale of Stock [Line Items]
Ownership interest, public		37.60%

Acquisitions and Divestitures_3

Acquisitions and Divestitures (Non-cash (Decreases) Increases Related to the Simplification Transaction) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest		$ (4.2)
Deferred income taxes	$ (43.7)	(0.3)
Share issuances, for the acquisition of Partnership public units	0
Common Stock
Subsidiary, Sale of Stock [Line Items]
Share issuances, for the acquisition of Partnership public units	0.3
Additional Paid-In Capital
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest		(1.5)
Deferred income taxes	(43.7)	$ (0.3)
Share issuances, for the acquisition of Partnership public units	182.2
Simplification Transaction
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest	(182.5)
Deferred income taxes	(43.7)
Simplification Transaction | Common Stock
Subsidiary, Sale of Stock [Line Items]
Share issuances, for the acquisition of Partnership public units	0.3
Simplification Transaction | Additional Paid-In Capital
Subsidiary, Sale of Stock [Line Items]
Share issuances, for the acquisition of Partnership public units	$ 225.9

Acquisitions and Divestitures_4

Acquisitions and Divestitures (Schedule of Non-Controlling Interest) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsidiary, Sale of Stock [Line Items]
Net (loss) income attributable to SunCoke Energy, Inc.	$ 3.7	$ (152.3)	$ 26.2
Increase (decrease) in SunCoke Energy, Inc. equity for the purchase of additional interest in the Partnership		182.5	(1.2)
Changes from net (loss) income attributable to SunCoke Energy, Inc. and transfers to noncontrolling interest		$ 30.2	$ 25
Public Unit Purchase Program
Subsidiary, Sale of Stock [Line Items]
Units purchased (in shares)			231,171
Acquisition of additional interest in the Partnership			$ 4.2

Acquisitions and Divestitures_5

Acquisitions and Divestitures (Divestiture of India Equity Method Investment) (Details) - USD ($) $ in Millions	Jun. 27, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Sale of equity method investment		$ 0	$ 0	$ 4
Recognition of accumulated currency translation loss upon sale of equity method investment in VISA SunCoke		0	0	(9)
Transaction costs		0	5.2	0.4
Loss from equity method investment		$ 0	$ 0	5.4
VISA SunCoke
Investment [Line Items]
Ownership percentage (as a percent)	49.00%
VISA SunCoke
Investment [Line Items]
Sale of equity method investment	$ 4
Recognition of accumulated currency translation loss upon sale of equity method investment in VISA SunCoke	$ (9)
Transaction costs				0.4
Loss from equity method investment				$ 5.4

Customer Concentrations (Narrat

Customer Concentrations (Narrative) (Details) - Customer Concentration Risk T in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020USD ($)T	Dec. 31, 2019USD ($)
Concentration Risk [Line Items]
Quantity of coke sold to three primary customers (in tons) | T			3.8
Cliffs | Accounts Receivable
Concentration Risk [Line Items]
Accounts receivable due, net			$ 22.9
U.S. Steel | Accounts Receivable
Concentration Risk [Line Items]
Accounts receivable due, net			$ 6.3	$ 7.3
AM USA | Accounts Receivable
Concentration Risk [Line Items]
Accounts receivable due, net				19.5
AK Steel | Accounts Receivable
Concentration Risk [Line Items]
Accounts receivable due, net				$ 13.2
Forecast | Cliffs
Concentration Risk [Line Items]
Percent of cokemaking capacity	65.00%	75.00%

Customer Concentrations (Sales

Customer Concentrations (Sales and Receivables to Significant Customers) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Concentration Risk [Line Items]
Sales and other operating revenue	$ 1,333	$ 1,600.3	$ 1,450.9
Cliffs/AM USA | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue	$ 687.3
Percent of Company sales and other operating revenue	51.60%
Cliffs/AK Steel | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue	$ 355.8
Percent of Company sales and other operating revenue	26.70%
U.S. Steel | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue	$ 208.2	$ 255.4	$ 206.8
Percent of Company sales and other operating revenue	15.60%	16.00%	14.30%
AM USA | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue		$ 786.4	$ 695.6
Percent of Company sales and other operating revenue		49.10%	47.90%
AK Steel | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue		$ 433.3	$ 377.9
Percent of Company sales and other operating revenue		27.10%	26.00%
Cliffs Steel/AM USA and Cliffs Steel/AK Steel | Sales Revenue, Net | Customer Concentration Risk
Concentration Risk [Line Items]
Sales and other operating revenue		$ 1,043.1
Percent of Company sales and other operating revenue		78.30%

Income Taxes (Components of Inc

Income Taxes (Components of Income From Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Domestic	$ 6.1	$ (218.6)	$ 39.3
Foreign	13	15.5	17.7
Total	$ 19.1	$ (203.1)	$ 57

Income Taxes (Components of I_2

Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current tax (benefit) expense:
U.S. federal	$ (4.7)	$ 0.3	$ 1.4
State	(0.3)	3.8	2.1
Foreign	3.2	4.3	4.5
Total current tax (benefit) expense	(1.8)	8.4	8
Deferred tax expense (benefit):
U.S. federal	3.6	(39.3)	(3.1)
State	8.5	(23.8)	(0.3)
Total deferred tax expense (benefit)	12.1	(63.1)	(3.4)
Income tax expense (benefit)	$ 10.3	$ (54.7)	$ 4.6

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Income Tax Expense to US Statutory Rate) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of income tax expense
Income tax expense (benefit) at U.S. statutory rate		$ 4	$ (42.7)	$ 12
Income attributable to noncontrolling interests in partnerships		(1.1)	(0.6)	(3.9)
State and other income taxes, net of federal income tax effects(2)		7.8	(15)	1.6
Impact Of CARES Act		(1.5)	0	0
Logistics goodwill impairment		0	3.3	0
Impact of Tax Legislation		0	0	(4.8)
Return to provision adjustments		1.2	(0.8)	0
Change in valuation allowance		(1.3)	0.6	0.7
Other		1.2	0.5	(1)
Income tax expense (benefit)		$ 10.3	$ (54.7)	$ 4.6
Reconciliation of income tax expense (as a percent)
Income tax expense (benefit) at U.S. statutory rate		21.00%	21.00%	21.00%
Income attributable to noncontrolling interests in partnerships		(5.60%)	0.30%	(6.80%)
State and other income taxes, net of federal income tax effects(2)		41.20%	7.40%	2.80%
Impact Of CARES Act		(7.90%)	0.00%	0.00%
Logistics goodwill impairment		0.00%	(1.70%)	0.00%
Impact of Tax Legislation		0.00%	0.00%	(8.40%)
Return to provision adjustments		6.50%	0.40%	0.00%
Change in valuation allowance		(6.90%)	(0.30%)	1.20%
Other		6.00%	(0.20%)	(1.80%)
Total effective income tax expense		54.30%	26.90%	8.00%
Income tax expense attributable to noncontrolling interests		$ 6.5
Tax refund		4.8
CARES Act, income tax benefit		$ 1.5
Benefit from foreign tax credits	$ 4.8

Income Taxes (Components of Net

Income Taxes (Components of Net Deferred Tax Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Retirement benefit liabilities	$ 6.3	$ 6.4
Black lung benefit liabilities	14.8	12.8
Share-based compensation	4.2	4.7
Federal tax credit carryforward	19.9	20.5
Foreign tax credit carryforward	19.4	14.4
Federal net operating loss	5.3	1.6
Section 163(j) interest limitation carryforward	0	5.7
State tax credit carryforward, net of federal income tax effects	0.3	1.1
State net operating loss carryforward, net of federal income tax effects	12.9	13.6
Other liabilities not yet deductible	11.5	4.4
Total deferred tax assets	94.6	85.2
Less valuation allowance	(19.6)	(20.9)
Deferred tax asset, net	75	64.3
Deferred tax liabilities:
Properties, plants and equipment	(152.9)	(17.9)
Investment in partnerships	(81.4)	(194)
Total deferred tax liabilities	(234.3)	(211.9)
Net deferred tax liability	(159.3)	$ (147.6)
Provisional income tax expense (benefit)	$ 10.7

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
State and foreign income tax returns subject to examination period (in years)	3 years
State and foreign income tax returns subject to examination period maximum (in years)	5 years
Period amended federal returns remain subject to examination	1 year
Uncertain tax positions	$ 0	$ 0
Interest and penalties	$ 0	$ 0	$ 0

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Coal	$ 60.6	$ 94.4
Coke	21.1	8.1
Materials, supplies and other	44.9	44.5
Total inventories	$ 126.6	$ 147

Properties, Plants, and Equip_2

Properties, Plants, and Equipment, Net (Components) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Gross investment, at cost	$ 2,360.9	$ 2,293.9
Less: accumulated depreciation	(1,032.9)	(903.7)
Total properties, plants and equipment, net	1,328	1,390.2
Coke and energy plant, machinery and equipment
Property, Plant and Equipment [Line Items]
Gross investment, at cost	2,009.3	1,968.2
Logistics plant, machinery and equipment
Property, Plant and Equipment [Line Items]
Gross investment, at cost	157.3	147.9
Land and land improvements
Property, Plant and Equipment [Line Items]
Gross investment, at cost	104.5	106
Construction-in-progress
Property, Plant and Equipment [Line Items]
Gross investment, at cost	47.4	29.5
Other
Property, Plant and Equipment [Line Items]
Gross investment, at cost	$ 42.4	$ 42.3

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Goodwill Narrative) (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Goodwill [Line Items]
Goodwill impairment		$ 73.5
Logistics
Goodwill [Line Items]
Goodwill impairment	$ 73.5	$ 73.5
Logistics | Discount Rate
Goodwill [Line Items]
Discount rate	0.12

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Goodwill
Net balances at December 31, 2018	$ 76.9	$ 3.4	$ 76.9
Impairment			(73.5)
Net balances at December 31, 2019 and 2020		3.4	3.4
Domestic Coke
Goodwill
Net balances at December 31, 2018	3.4	3.4	3.4
Impairment		0	0
Net balances at December 31, 2019 and 2020		3.4	3.4
Logistics
Goodwill
Net balances at December 31, 2018	73.5	0	73.5
Impairment	$ (73.5)		(73.5)
Net balances at December 31, 2019 and 2020		$ 0	$ 0

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets (Intangible Assets Narrative) (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2019USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Finite-Lived Intangible Assets [Line Items]
Long-lived asset and goodwill impairment		$ 0	$ 247.4	$ 0
Total amortization expense of intangible assets		$ 2.5	$ 8.8	$ 11.1
Permits
Finite-Lived Intangible Assets [Line Items]
Useful life		22 years
Convent Marine Terminal
Finite-Lived Intangible Assets [Line Items]
Impairment of property, plants and equipments	$ 113.3
Convent Marine Terminal | Permits
Finite-Lived Intangible Assets [Line Items]
Useful life		27 years
Average remaining renewal term		3 years 4 months 24 days
Convent Marine Terminal | Discount Rate
Finite-Lived Intangible Assets [Line Items]
Discount rate	0.11
Long-lived assets | Logistics
Finite-Lived Intangible Assets [Line Items]
Long-lived asset and goodwill impairment	$ 173.9
Long-lived assets | Convent Marine Terminal
Finite-Lived Intangible Assets [Line Items]
Fair value of long-lived assets	112.1
Long-lived asset and goodwill impairment	$ 60.6

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets (Gross and Net Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 40	$ 46.1
Accumulated Amortization	6.2	11.4
Total	33.8	34.7
Customer contracts
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	0	7.7
Accumulated Amortization	0	7.2
Total	$ 0	0.5
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted - Average Remaining Amortization Years	4 years
Gross Carrying Amount	$ 6.7	6.7
Accumulated Amortization	4.5	3.9
Total	$ 2.2	2.8
Permits
Finite-Lived Intangible Assets [Line Items]
Weighted - Average Remaining Amortization Years	22 years
Gross Carrying Amount	$ 31.7	31.7
Accumulated Amortization	1.7	0.3
Total	$ 30	31.4
Other
Finite-Lived Intangible Assets [Line Items]
Weighted - Average Remaining Amortization Years	30 years
Gross Carrying Amount	$ 1.6	0
Accumulated Amortization	0	0
Total	$ 1.6	$ 0

Goodwill and Other Intangible_7

Goodwill and Other Intangible Assets (Schedule of Future Amortization Expense) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
2021	$ 2
2022	2
2023	2
2024	1.9
2025	1.5
Thereafter	24.4
Total	$ 33.8	$ 34.7

Asset Retirement Obligations (D

Asset Retirement Obligations (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of changes in the asset retirement obligation
Beginning Balance	$ 15,300,000	$ 14,600,000
Liabilities settled	(100,000)	(1,200,000)
Accretion expense	1,100,000	1,000,000
Revisions in estimated cash flows(2)	(4,900,000)	900,000
Ending Balance	11,400,000	15,300,000
Current portion of asset retirement obligation liabilities	$ 0	$ 900,000

Retirement Benefits Plans (Narr

Retirement Benefits Plans (Narrative) (Details) - USD ($) $ in Millions	Jan. 01, 2011	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Company's pretax income and the aggregate compensation levels of participating employees		$ 6.6	$ 6.8	$ 6.5
Postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Years of service, less than	10 years
Health care cost trend assumption increased health care cost trend rates (as a percent)		6.25%	6.25%
Health care cost trend assumption increased health care cost trend rates (as a percent)		5.00%

Retirement Benefits Plans (Post

Retirement Benefits Plans (Postretirement Benefit Plans (Benefit) Expense Components) (Details) - Postretirement benefit plans - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligations	$ 0.7	$ 1.1	$ 1
Amortization of:
Actuarial losses	0.7	0.6	0.6
Prior service benefit	(0.5)	(0.6)	(0.7)
Total expense	$ 0.9	$ 1.1	$ 0.9

Retirement Benefits Plans (Assu

Retirement Benefits Plans (Assumptions Used to Determine Defined Benefit Plan and Postretirement Benefit Plans Expense (Benefit) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.90%	4.00%	3.35%

Retirement Benefits Plans (Amou

Retirement Benefits Plans (Amounts Recognized as Components of Other Comprehensive (Loss) Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reclassifications to earnings of:
Prior service benefit amortization	$ (0.1)	$ 0	$ 0.1
Retirement benefit plan funded status adjustments:
Actuarial (losses) gains	1.6	0.7	(0.6)
Total	(0.1)		0.1
Postretirement benefit plans
Reclassifications to earnings of:
Actuarial loss amortization	0.7	0.6	0.6
Prior service benefit amortization	(0.5)	(0.6)	(0.7)
Retirement benefit plan funded status adjustments:
Actuarial (losses) gains	(2)	(1)	0.8
Total	$ (1.8)	$ (1)	$ 0.7

Retirement Benefits Plans (Comp

Retirement Benefits Plans (Components of the Changes in Benefit Obligations and Fair Value of Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Change in Benefit Obligation
Current portion of retirement liabilities classified in accrued liabilities	$ 2.8	$ 2.9
Postretirement benefit plans
Change in Benefit Obligation
Benefit obligation at beginning of year	27.4	28.2
Interest cost	0.7	1.1	$ 1
Actuarial loss	2	1
Benefits paid	(2.6)	(2.9)
Benefit obligations at end of year	$ 27.5	$ 27.4	$ 28.2

Retirement Benefits Plans (Cumu

Retirement Benefits Plans (Cumulative Amounts Not Yet Recognized in Net Income) (Details) - Postretirement benefit plans - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Cumulative amounts not yet recognized in net (loss) income:
Actuarial losses	$ 12.1	$ 10.8
Prior service benefits	(1.5)	(2)
Accumulated other comprehensive loss (before related tax benefit)	$ 10.6	$ 8.8

Retirement Benefits Plans (Expe

Retirement Benefits Plans (Expected Benefit Payments) (Details) - Postretirement benefit plans $ in Millions	Dec. 31, 2020USD ($)
Regulatory Liabilities [Line Items]
2021	$ 2.8
2022	2.6
2023	2.4
2024	2.2
2025	2
2026 through 2030	$ 8.1

Retirement Benefits Plans (Disc

Retirement Benefits Plans (Discount Rate) (Details)	Dec. 31, 2020	Dec. 31, 2019
Postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	2.00%	2.90%

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Accrued benefits	$ 18.3	$ 21.7
Current portion of postretirement benefit obligation	2.8	2.9
Other taxes payable	9.8	9.9
Current portion of black lung liability	4.6	4.6
Accrued legal	6.4	2.7
Other	7.9	5.5
Total accrued liabilities	$ 49.8	$ 47.3

Debt and Financing Obligation_2

Debt and Financing Obligations (Schedule of Debt) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total borrowings	$ 690,500,000	$ 800,500,000
Original issue discount	(3,300,000)	(4,300,000)
Debt issuance costs	(10,300,000)	(13,300,000)
Total debt and financing obligation	676,900,000	782,900,000
Current portion of financing obligations	3,000,000	2,900,000
Long-term debt and financing obligations	673,900,000	780,000,000
Senior Notes, Due 2025 [Member] | Senior notes
Debt Instrument [Line Items]
Total borrowings	$ 587,300,000	650,000,000
Interest rate on senior notes (as a percent)	7.50%
$400.0 revolving credit facility, due 2024 ("Revolving Facility") | Line of Credit | Revolving credit facility
Debt Instrument [Line Items]
Total borrowings	$ 88,300,000	143,300,000
Principal amount of term loan	400,000,000
5.35 percent financing obligation, due 2024 | Financing Obligation
Debt Instrument [Line Items]
Total borrowings	$ 14,900,000	$ 7,200,000
Interest rate on senior notes (as a percent)	5.35%

Debt and Financing Obligation_3

Debt and Financing Obligations (2025 Senior Notes) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt, net	$ 5,700,000	$ 1,500,000	$ (300,000)
Senior notes | Senior Notes, Due 2025 [Member]
Debt Instrument [Line Items]
Repurchased face value	62,700,000
Debt prepayment cost	55,900,000
Gain (loss) on extinguishment of debt, net	$ 5,700,000
SunCoke Energy Partners, L.P. | Senior notes | Senior Notes, Due 2025 [Member]
Debt Instrument [Line Items]
Percentage of principal amount	100.00%
Change of control percent	101.00%
SunCoke Energy Partners, L.P. | Senior notes | Senior Notes, Due 2025 [Member] | On or After June 15, 2020
Debt Instrument [Line Items]
Redemption percentage	35.00%
Percentage of principal amount	105.60%
SunCoke Energy Partners, L.P. | Senior notes | Senior Notes, Due 2025 [Member] | June 15, 2021
Debt Instrument [Line Items]
Redemption percentage	1.90%
SunCoke Energy Partners, L.P. | Senior notes | Senior Notes, Due 2025 [Member] | June 15, 2023
Debt Instrument [Line Items]
Redemption percentage	100.00%

Debt and Financing Obligation_4

Debt and Financing Obligations (Revolving Facility) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Outstanding balance	$ 690.5	$ 800.5
Revolving credit facility | Line of Credit | $400.0 revolving credit facility, due 2024 ("Revolving Facility")
Debt Instrument [Line Items]
Letters of credit outstanding under revolving facility	11.8
Outstanding balance	88.3	$ 143.3
Remaining borrowing capacity	$ 299.9
Unused capacity commitment fee	0.25%
The weighted-average interest rate for borrowings outstanding under credit agreement (as a percent)	2.60%
Revolving credit facility | Line of Credit | $400.0 revolving credit facility, due 2024 ("Revolving Facility") | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Revolving credit facility | Line of Credit | $400.0 revolving credit facility, due 2024 ("Revolving Facility") | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Letter of Credit | Line of Credit | $400.0 revolving credit facility, due 2024 ("Revolving Facility")
Debt Instrument [Line Items]
Outstanding balance	$ 11.5

Debt and Financing Obligation_5

Debt and Financing Obligations (Financing Obligation) (Details) - Integral Equipment and Mobile Equipment - Domestic Coke and Coal Logistics	12 Months Ended
	Dec. 31, 2020
Sale Leaseback Transaction [Line Items]
Initial lease period	48 months
Buyout option period	36 months

Debt and Financing Obligation_6

Debt and Financing Obligations (Covenants) (Details) - Credit Agreement and Partner Revolver	Dec. 31, 2020USD ($)
Line of Credit Facility [Line Items]
Maximum consolidated leverage ratio	4.50
Minimum consolidated interest coverage ratio	2.50
SunCoke Energy Partners, L.P.
Line of Credit Facility [Line Items]
Cross default covenant threshold	$ 35,000,000

Debt and Financing Obligation_7

Debt and Financing Obligations (Schedule of Long-Term Debt Maturity) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2021	$ 3
2022	3.2
2023	3.3
2024	93.7
2025	587.3
2026-Thereafter	0
Total	$ 690.5	$ 800.5

Commitments and Contingent Li_3

Commitments and Contingent Liabilities (Legal Matters) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Commitments and Contingencies Disclosure [Abstract]
Legal fees	$ 1

Commitments and Contingent Li_4

Commitments and Contingent Liabilities (Black Lung Benefit Liabilities) (Details) $ in Millions	Feb. 21, 2020USD ($)	Dec. 31, 2020USD ($)claim	Dec. 31, 2019USD ($)claim	Dec. 31, 2018USD ($)	Dec. 31, 2013USD ($)
Black Lung Benefit
Defined Benefit Plan Disclosure [Line Items]
Discount rate		2.00%	2.90%
Active claims | claim		309	324
Black lung liability		$ 64.6	$ 55.1
Increase in black lung expense		1.6
Current portion of black lung liability		4.6	4.6
Payments		6	5.2	$ 6.3
Expense (1)		$ 15.4	$ 10.9	$ 5.4
Uninsured Risk
Defined Benefit Plan Disclosure [Line Items]
Payments	$ 40.4				$ 8.4

Leases - Narrative (Details)

Leases - Narrative (Details)	Dec. 31, 2020
Minimum
Lessee, Lease, Description [Line Items]
Option to extend, operating lease	1 month
Maximum
Lessee, Lease, Description [Line Items]
Option to extend, operating lease	50 years

Leases - Lease Expense (Details

Leases - Lease Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating leases:
Operating lease cost	$ 2.3	$ 2.4
Short-term leases:
Total lease expense	8.7	11.7
Cost of products sold and operating expenses
Operating leases:
Operating lease cost	1.8	1.9
Short-term leases:
Cost of products sold and operating expenses	6.4	9.3
Selling, general and administrative expenses
Operating leases:
Operating lease cost	$ 0.5	$ 0.5

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Operating ROU assets	$ 10.8	$ 12.4
Operating ROU assets, extensible list	us-gaap:OtherAssets
Operating lease liabilities extensible list	us-gaap:LiabilitiesAbstract	us-gaap:LiabilitiesAbstract
Total operating lease liabilities	$ 10.2	$ 11.7
Accrued liabilities
Lessee, Lease, Description [Line Items]
Current operating lease liabilities	2	1.9
Other deferred credits and liabilities
Lessee, Lease, Description [Line Items]
Noncurrent operating lease liabilities	$ 8.2	$ 9.8

Leases - Weighted Average (Deta

Leases - Weighted Average (Details)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Weighted average remaining lease term of operating leases	7 years 3 months 18 days	7 years 10 months 24 days
Weighted average discount rate of operating leases	4.70%	4.80%

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Leases:
Cash paid for amounts included in the measurement of operating lease liabilities	$ 2.3	$ 3.9
ROU assets obtained in exchange for new operating lease liabilities	$ 0.2	$ 7.9

Leases - Maturities (Details)

Leases - Maturities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Operating Leases
2021	$ 2.3
2022	1.7
2023	1.4
2024	1.3
2025	1.3
2026-Thereafter	4
Total lease payments	12
Less: imputed interest	1.8
Total lease liabilities	$ 10.2	$ 11.7

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Components of accumulated other comprehensive (loss) income (net of related income taxes)
Beginning balance	$ 518.4	$ 682.7	$ 659.6
Other comprehensive loss before reclassifications / adjustments	(1.1)	(0.6)
Retirement benefit plans funded status adjustment	(1.6)	(0.7)	0.6
Net current period change in accumulated other comprehensive loss	(2.7)	(1.3)
Ending balance	500.9	518.4	682.7
Benefit Plans
Components of accumulated other comprehensive (loss) income (net of related income taxes)
Beginning balance	(6.7)	(6)
Other comprehensive loss before reclassifications / adjustments	0.1	0
Retirement benefit plans funded status adjustment	(1.6)	(0.7)
Net current period change in accumulated other comprehensive loss	(1.5)	(0.7)
Ending balance	(8.2)	(6.7)	(6)
Tax benefit associated with benefit plans	2.4	2.1
Currency Translation Adjustments
Components of accumulated other comprehensive (loss) income (net of related income taxes)
Beginning balance	(7.7)	(7.1)
Other comprehensive loss before reclassifications / adjustments	(1.2)	(0.6)
Retirement benefit plans funded status adjustment	0	0
Net current period change in accumulated other comprehensive loss	(1.2)	(0.6)
Ending balance	(8.9)	(7.7)	(7.1)
Accumulated Other Comprehensive Loss
Components of accumulated other comprehensive (loss) income (net of related income taxes)
Beginning balance	(14.4)	(13.1)	(21.2)
Retirement benefit plans funded status adjustment	(1.6)	(0.7)	0.6
Ending balance	$ (17.1)	$ (14.4)	$ (13.1)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss Reclassification Adjustments From AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Recognition of accumulated currency translation loss upon sale of equity method investment in VISA SunCoke	$ 0	$ 0	$ (9)
Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total, net of tax	(0.1)	0	(8.9)
Actuarial loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of benefit plans to net income	(0.6)	(0.6)	(0.6)
Prior service benefit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of benefit plans to net income	$ 0.5	$ 0.6	$ 0.7

Share-Based Compensation (Equit

Share-Based Compensation (Equity Classified Awards Narrative) (Details)	12 Months Ended
	Dec. 31, 2020USD ($)installmentInstallment	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Feb. 14, 2018shares	Jul. 13, 2011shares
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised | $		$ 0	$ 800,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual installment in which stock option exercisable | Installment	3
Period from grant date for annual installment (in years)	1 year
Total fair value of non-option award units vested | $	$ 600,000	$ 200,000	$ 1,200,000
SunCoke LTPEP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issuable (in shares) | shares				6,000,000	1,600,000
Common stock issuable pursuant to new awards (in shares) | shares				1,500,000	7,500,000
SunCoke LTPEP | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual installment in which stock option exercisable | installment	3
Period from grant date for annual installment (in years)	1 year
Expiration period	10 years
SunCoke LTPEP | Performance Share Units | ROIC Portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of award allocation	50.00%
Measurement period	3 years
SunCoke LTPEP | Performance Share Units | TSR Portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement period	3 years
SunCoke LTPEP | Performance Share Units | TSR Portion | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	75.00%	25.00%	25.00%
Percentage adjustment of award determined by pre-tax return on capital (as a percent)	0.00%
SunCoke LTPEP | Performance Share Units | TSR Portion | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	125.00%	125.00%	125.00%
Percentage adjustment of award determined by pre-tax return on capital (as a percent)	250.00%

Share-Based Compensation (Stock

Share-Based Compensation (Stock Option and Performance Share Units Grants) (Details) - SunCoke LTPEP - Stock Options - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (shares)	0	267,897	78,447
Weighted average exercise price (in USD per share)		$ 9.87	$ 10.49
Weighted-average fair value stock option (in dollars per share)		$ 4.09	$ 5.38

Share-Based Compensation (Assum

Share-Based Compensation (Assumptions Used to Calculate Value of Stock Options) (Details) - Stock Options	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free interest rate	2.00%	3.00%
Expected term	6 years	6 years
Volatility	53.00%	52.00%
Dividend yield	2.00%	0.00%

Share-Based Compensation (Summa

Share-Based Compensation (Summary of Stock Option Activity) (Details) - Stock Options - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Number of Options (in shares)
Outstanding at the beginning of period (shares)	3,136,831
Exercised (shares)	(2,825)
Forfeited (shares)	(33,146)
Outstanding at end of period (shares)	3,100,860	3,136,831
Exercisable at end of period (shares)	2,733,205
Expected to vest at end of period (shares)	367,655
Weighted Average Exercise Price (in dollars per share)
Outstanding at beginning of period (in USD per share)	$ 15.02
Exercised (in USD per share)	3.80
Forfeited (in USD per share)	12.25
Outstanding at end of period (in USD per share)	15.02	$ 15.02
Exercisable at end of period (in USD per share)	15.69
Expected to vest at end of period (in USD per share)	$ 10.01
Weighted Average Remaining Contractual Term (years)
Weighted average remaining contractual term (in years)	3 years 2 months 12 days	4 years 3 months 18 days
Exercisable at end of period	2 years 4 months 24 days
Expected to vest at end of period	7 years 9 months 18 days
Aggregate Intrinsic Value (millions)
Aggregate intrinsic value	$ 0.1	$ 0.3
Exercisable at end of period	0.1
Expected to vest at end of period	$ 0

Share-Based Compensation (Restr

Share-Based Compensation (Restricted Stock Units and Performance Share Units Granted) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (shares)	304,332	136,425	32,128
Weighted Average Grant-Date Fair Value (in USD per share)	$ 6.04	$ 9.87	$ 10.49
Grant Date Fair Value	$ 1.8	$ 1.3	$ 0.3
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (shares)	228,248	227,378	96,389
Weighted Average Grant-Date Fair Value (in USD per share)	$ 6.70	$ 10.79	$ 11.36
Grant Date Fair Value	$ 1.5	$ 2.5	$ 1.1

Share-Based Compensation (Sum_2

Share-Based Compensation (Summary of RSUs and PSUs Outstanding) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Stock Units (RSUs)
Number of Units
Outstanding at beginning of period (shares)	165,384
Granted (shares)	304,332	136,425	32,128
Vested (shares)	(63,729)
Forfeited (shares)	0
Outstanding at end of period (shares)	405,987	165,384
Weighted Average Grant- Date Fair Value (in dollars per share)
Outstanding at beginning of period (in USD per share)	$ 9.95
Granted (in USD per share)	6.04	$ 9.87	$ 10.49
Vested (in USD per share)	9.97
Forfeited (in USD per share)	0
Outstanding at end of period (in USD per share)	$ 7.02	$ 9.95
Performance Share Units
Number of Units
Outstanding at beginning of period (shares)	575,363
Granted (shares)	228,248	227,378	96,389
Vested (shares)	(92,992)
Forfeited (shares)	(25,316)
Outstanding at end of period (shares)	685,303	575,363
Weighted Average Grant- Date Fair Value (in dollars per share)
Outstanding at beginning of period (in USD per share)	$ 11.20
Granted (in USD per share)	6.70	$ 10.79	$ 11.36
Vested (in USD per share)	11.40
Forfeited (in USD per share)	11.40
Outstanding at end of period (in USD per share)	$ 9.76	$ 11.20

Share-Based Compensation (Liabi

Share-Based Compensation (Liability Classified Awards Narrative) (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)Installment$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares
Restricted Stock Units Settled in Cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (shares) | shares	263,998	147,851	98,364
Number of annual installment in which stock option exercisable | Installment	3
Period from grant date for annual installment (in years)	1 year
Granted (in USD per share) | $ / shares	$ 6.04	$ 9.66	$ 10.71
Closing price (USD per share) | $ / shares	$ 4.35
Cash Incentive Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of annual installment in which stock option exercisable | Installment	3
Cash Incentive Award | Suncoke LTCIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value award | $	$ 2	$ 0.6	$ 1
Percent of award allocation	50.00%
Measurement period	3 years

Share-Based Compensation (Compe

Share-Based Compensation (Compensation Expense and Unrecognized Compensation Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 0.1
Recognition Period	1 year 1 month 6 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 0.5
Recognition Period	1 year 10 months 24 days
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 1.5
Recognition Period	1 year 6 months
Restricted Stock Units Settled in Cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 0.6
Recognition Period	1 year 10 months 24 days
Suncoke LTCIP | Cash Incentive Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 1.2
Recognition Period	1 year 10 months 24 days
Selling, General and Administrative Expenses | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0.3	$ 1.1	$ 0.5
Net of tax	0.3	0.9	0.4
Selling, General and Administrative Expenses | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	1.9	1	0.4
Net of tax	1.5	0.9	0.3
Selling, General and Administrative Expenses | Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	1.5	2.2	1.9
Net of tax	1.2	1.8	1.7
Selling, General and Administrative Expenses | Equity Classified Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	3.7	4.3	2.8
Net of tax	3	3.6	2.4
Selling, General and Administrative Expenses | Restricted Stock Units Settled in Cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.8	0.9	0.8
Net of tax	0.6	0.7	0.6
Selling, General and Administrative Expenses | Suncoke LTCIP | Cash Incentive Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	0.6	0.4	0.9
Net of tax	0.4	0.3	0.7
Selling, General and Administrative Expenses | Suncoke LTCIP | Liability Classified Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	1.4	1.3	1.7
Net of tax	$ 1	$ 1	$ 1.3

Share-Based Compensation (Sum_3

Share-Based Compensation (Summary of Share-Based Compensation Expense Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Director
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Compensation expense	$ 0.1	$ 0.2	$ 0.3

Earnings Per Share - Weighted A

Earnings Per Share - Weighted Average Number of Shares (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Weighted-average number of common shares outstanding-basic	83	76.8	64.7
Add: effect of dilutive share-based compensation awards	0.2	0	0.8
Weighted-average number of shares-diluted	83.2	76.8	65.5

Earnings Per Share - Antidiluti

Earnings Per Share - Antidilutive Shares Excluded From EPS Calculation (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive effect excluded from the computation of diluted weighted-average shares outstanding (in shares)	3.7	3.5	2.8
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive effect excluded from the computation of diluted weighted-average shares outstanding (in shares)	3.2	3	2.7
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive effect excluded from the computation of diluted weighted-average shares outstanding (in shares)	0.2	0.1	0
Performance Share Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive effect excluded from the computation of diluted weighted-average shares outstanding (in shares)	0.3	0.4	0.1

Fair Value Measurements (Financ

Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration adjustments	$ 0	$ 4,200,000	$ (2,500,000)
Cost of products sold and operating expenses
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration adjustments			2,500,000
Level 3 | SunCoke Energy Partners, L.P. | Convent Marine Terminal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		$ 0	$ 5,000,000	$ 0

Fair Value Measurements (Certai

Fair Value Measurements (Certain Financial Assets and Liabilities not Measured at Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value of long-term debt	$ 683.9	$ 776.1
Outstanding balance	$ 690.5	$ 800.5

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Narrative (Details) T in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)T
Cokemaking
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Capacity (in tons)	4.1
Percentage of facility capacity	90.00%
Unsatisfied performance obligation (in tons)	17.6
Average remaining term	6 years
Logistics
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Average remaining term	3 years
Performance obligation amount | $	$ 35

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Disaggregated Sales and Other Operating Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	$ 1,333	$ 1,600.3	$ 1,450.9
Cokemaking
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	1,218.9	1,434.9	1,250.5
Energy
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	43.6	51.1	49.7
Logistics
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	35.5	72.1	101
Operating and licensing fees
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	31.6	38.4	40.4
Other
Disaggregation of Revenue [Line Items]
Sales and other operating revenue	$ 3.4	$ 3.8	$ 9.3

Business Segment Information -

Business Segment Information - Narrative (Details)	12 Months Ended
	Dec. 31, 2020segment
Segment Reporting [Abstract]
Number of reportable segments	3

Business Segment Information _2

Business Segment Information - Segment Profit or Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ 1,333	$ 1,600.3	$ 1,450.9
Adjusted EBITDA:	205.9	247.9	263.2
Depreciation and amortization expense	133.7	143.8	141.6
Capital expenditures	73.9	110.1	100.3
Corporate and Other
Segment Reporting Information [Line Items]
Adjusted EBITDA:	(41.9)	(37.4)	(35.7)
Depreciation and amortization expense	1.3	1.3	1.4
Research and development expense	3.9
Coal Mining
Segment Reporting Information [Line Items]
Adjusted EBITDA:	13.2	11.2	9.8
Operating Segments | Domestic Coke
Segment Reporting Information [Line Items]
Sales and other operating revenues	1,265.4	1,489.1	1,308.3
Adjusted EBITDA:	217	226.7	207.9
Depreciation and amortization expense	119.1	120.5	114.4
Capital expenditures	60	105.2	94.9
Operating Segments | Brazil Coke
Segment Reporting Information [Line Items]
Sales and other operating revenues	31.6	38.4	40.4
Adjusted EBITDA:	13.5	16	18.4
Depreciation and amortization expense	0.5	0.6	0.7
Capital expenditures	0.4	0.3	0.2
Operating Segments | Logistics
Segment Reporting Information [Line Items]
Sales and other operating revenues	36	72.8	102.2
Adjusted EBITDA:	17.3	42.6	72.6
Depreciation and amortization expense	12.8	21.4	25.1
Capital expenditures	13.5	4.6	5.2
Elimination of intersegment sales
Segment Reporting Information [Line Items]
Sales and other operating revenues	(22.1)	(26.3)	(24.5)
Elimination of intersegment sales | Logistics
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ 22.1	$ 26.3	$ 24.5

Business Segment Information _3

Business Segment Information - Segment Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Segment assets, excluding income tax receivable	$ 1,607.9	$ 1,751.6
Income tax receivable	5.5	2.2
Total assets	1,613.4	1,753.8
Corporate and Other
Segment Reporting Information [Line Items]
Segment assets, excluding income tax receivable	31.8	102
Operating Segments | Domestic Coke
Segment Reporting Information [Line Items]
Segment assets, excluding income tax receivable	1,358.9	1,434.2
Operating Segments | Brazil Coke
Segment Reporting Information [Line Items]
Segment assets, excluding income tax receivable	17.7	14.6
Operating Segments | Logistics
Segment Reporting Information [Line Items]
Segment assets, excluding income tax receivable	$ 199.5	$ 200.8

Business Segment Information _4

Business Segment Information - Adjusted EBITDA (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Business Acquisition [Line Items]
Net (loss) income attributable to SunCoke Energy, Inc.	$ 3,700,000	$ (152,300,000)	$ 26,200,000
Less: Net income attributable to noncontrolling interests	5,100,000	3,900,000	20,800,000
Net income (loss)	8,800,000	(148,400,000)	47,000,000
Add:
Long-lived asset and goodwill impairment	0	247,400,000	0
Depreciation and amortization expense	133,700,000	143,800,000	141,600,000
Interest expense, net	56,300,000	60,300,000	61,400,000
(Gain) loss on extinguishment of debt, net	(5,700,000)	(1,500,000)	300,000
Income tax expense (benefit)	10,300,000	(54,700,000)	4,600,000
Contingent consideration adjustments	0	(4,200,000)	2,500,000
Restructuring Costs	2,500,000	0	0
Transaction costs	0	5,200,000	400,000
Loss from equity method investment	0	0	5,400,000
Adjusted EBITDA:	205,900,000	247,900,000	263,200,000
Subtract: Adjusted EBITDA attributable to noncontrolling interest	9,100,000	40,700,000	82,000,000
Adjusted EBITDA attributable to SunCoke Energy, Inc.	$ 196,800,000	207,200,000	181,200,000
Fair Value, Inputs, Level 3 | SunCoke Energy Partners, L.P. | CMT
Add:
Contingent consideration		$ 0	$ 5,000,000	$ 0