Number of annual Installment in which stock option exercisable.

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- Definition

Period from grant date for annual installment.

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- Definition

Share-based Compensation Arrangement by Share-base Payment Award, Terms of Award, Percentage Adjustment of Award Determined by Pre-Tax Return on Capital

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Measurement Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Measurement Results Payout Percentage

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Percent of Award Allocation

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- Definition

Stock option expiration period.

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Share-Based Compensation (Equity Classified Awards Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) installment shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares	May 12, 2022 shares
Omnibus Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock authorized (in shares)				2,700,000
Number of shares of common stock reserved (in shares)				2,434,445
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised \| $	$ 0.2	$ 0.3	$ 0.0
Restricted stock units
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 \| $	$ 1.7	$ 1.2	$ 0.6
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
Number of shares granted (in shares)	0	0	0
SunCoke LTPEP \| Performance stock 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 stock units \| TSR Portion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement period	3 years
SunCoke LTPEP \| Performance stock units \| TSR Portion \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	80.00%	75.00%	75.00%
Percentage adjustment of award determined by pre-tax return on capital (as a percent)	25.00%	25.00%	25.00%
SunCoke LTPEP \| Performance stock units \| TSR Portion \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout percentage	120.00%	125.00%	125.00%
Percentage adjustment of award determined by pre-tax return on capital (as a percent)	250.00%	250.00%	250.00%
Suncoke LTCIP \| Cash Incentive Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of award allocation	50.00%	50.00%	50.00%
Measurement period	3 years