Share-Based Compensation (Details Textual) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) days installment $ / shares shares	Mar. 31, 2015 USD ($)
Stock options
Share-based compensation (Textual) [Abstract]
Forfeiture rate (as a percent)	16.00%
Compensation expense	$ 0.5	$ 0.6
Unrecognized compensation cost	$ 2.4
Weighted average remaining contractual term (in years)	1 year 4 months
Stock options \| Executive Officer
Share-based compensation (Textual) [Abstract]
Forfeiture rate (as a percent)	0.00%
Stock options \| Suncoke LTPEP
Share-based compensation (Textual) [Abstract]
Number of annual installment in which stock option exercisable (in installments) \| installment	3
Period from grant date for annual installment (in years)	1 year
Stock options, time until expiration (in years)	10 years
Performance based options \| Suncoke LTPEP
Share-based compensation (Textual) [Abstract]
Closing stock price threshold for performance based options (in dollars per share) \| $ / shares	$ 9.5
Closing stock price threshold for performance based options, number of trading days \| days	15
Measurement period	3 years
Restricted stock units (RSUs)
Share-based compensation (Textual) [Abstract]
Forfeiture rate (as a percent)	18.00%
Compensation expense	$ 0.9	0.9
Unrecognized compensation cost	$ 2.9
Weighted average remaining contractual term (in years)	1 year 6 months
Performance share units
Share-based compensation (Textual) [Abstract]
Forfeiture rate (as a percent)	0.00%
Compensation expense	$ 0.3	$ 0.2
Unrecognized compensation cost	$ 4.0
Weighted average remaining contractual term (in years)	2 years 7 months
Performance share units \| Minimum
Share-based compensation (Textual) [Abstract]
Percent of original award granted	0.00%
Performance share units \| Maximum
Share-based compensation (Textual) [Abstract]
Percent of original award granted	200.00%
Restricted Stock Units Settled in Cash
Share-based compensation (Textual) [Abstract]
Number of annual installment in which stock option exercisable (in installments) \| installment	3
Period from grant date for annual installment (in years)	1 year
Forfeiture rate (as a percent)	18.00%
Closing price per share (in dollars per share) \| $ / shares	$ 6.50
Unrecognized compensation cost	$ 1.0
Weighted average remaining contractual term (in years)	2 years 6 months
Restricted stock (in shares) \| shares	196,908
Fair value grant (in dollars per share) \| $ / shares	$ 3.80
Cash Incentive Award \| Suncoke LTCIP
Share-based compensation (Textual) [Abstract]
Closing stock price threshold for performance based options (in dollars per share) \| $ / shares	$ 9
Closing stock price threshold for performance based options, number of trading days \| days	15
Measurement period	3 years
Forfeiture rate (as a percent)	16.00%
Unrecognized compensation cost	$ 0.7
Weighted average remaining contractual term (in years)	2 years 9 months
Grant date fair value of award	$ 0.9
Cash Incentive Award \| Suncoke LTCIP \| Maximum
Share-based compensation (Textual) [Abstract]
Percent of original award granted	200.00%

Number of annual Installment in which stock option exercisable.

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Period from grant date for annual installment.

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

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate

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- Definition

Share-based compensation.

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Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Closing Common Stock Price

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Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Closing Common Stock Price, Number of Trading Days

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

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value

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No definition available.

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- Definition

Share-based Compensation by Share-based Payment Award, Price Per Share

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No definition available.

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- Definition

Stock option expiration period.

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
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