Supplemental Condensed Consolidating Financial Information (Details 2) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Continuing Operating Activities:
Net (loss) income	$ (55,800,000)	$ 6,400,000	$ (48,400,000)	$ (4,000,000)	$ 18,700,000	$ 12,300,000	$ 12,700,000	$ 6,400,000	$ (101,800,000)	$ 50,100,000	$ 102,500,000
Adjustments to reconcile net income to net cash provided by continuing operating activities:
(Loss) income from discontinued operations, net of tax	40,100,000	18,500,000	41,200,000	6,200,000	4,400,000	3,600,000	2,800,000	4,700,000	106,000,000	15,500,000	(20,500,000)
Asset impairment									16,800,000	0	0
Depreciation and amortization expense									96,100,000	77,100,000	65,000,000
Deferred income tax expense (benefit)									(6,000,000)	500,000	30,400,000
Payments in Excess of Expense for Retirement Plans									(8,100,000)	(5,400,000)	(9,600,000)
Share-based compensation expense									9,800,000	7,600,000	6,700,000
Equity in Earnings of Subsidiaries									0	0	0
Excess tax benefit from share-based awards									(300,000)	0	0
Loss from equity method investment									35,000,000	2,200,000	0
Loss on extinguishment/modification of debt									15,400,000	0	0
Changes in working capital pertaining to continuing operating activities (net of acquisitions):
Receivables									9,900,000	(17,100,000)	(5,700,000)
Inventories									(10,500,000)	30,900,000	57,800,000
Accounts payable									(27,500,000)	25,200,000	(69,200,000)
Accrued liabilities									(17,900,000)	(22,800,000)	11,000,000
Interest payable									1,700,000	2,500,000	(200,000)
Income taxes									1,000,000	(10,100,000)	(17,600,000)
Accrual for black lung benefits									11,500,000	(2,400,000)	1,300,000
Other									(1,100,000)	2,900,000	(7,900,000)
Net cash provided by continuing operating activities									130,000,000	156,700,000	144,000,000
Cash Flows from Continuing Investing Activities:
Capital expenditures									(118,300,000)	(132,300,000)	(54,200,000)
Acquisition of businesses, net of cash acquired									0	(113,300,000)	0
Equity method investment in VISA SunCoke Limited									0	(67,700,000)	0
Net cash used in continuing investing activities									(118,300,000)	(313,300,000)	(54,200,000)
Cash Flows from Continuing Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs									90,500,000	237,800,000	0
Proceeds from issuance of long-term debt									268,100,000	150,000,000
Repayment of long-term debt									(276,500,000)	(225,000,000)	(3,300,000)
Debt issuance costs									(5,800,000)	(6,900,000)	0
Proceeds from revolving facility									40,000,000	40,000,000	0
Repayment of revolving facility									(80,000,000)	0	0
Cash distributions to noncontrolling interests									(32,300,000)	(17,800,000)	(2,300,000)
Shares repurchased									(85,100,000)	(10,900,000)	(9,400,000)
Proceeds from exercise of stock options									2,900,000	2,500,000	4,700,000
Excess tax benefit from share-based awards									300,000	0	0
Dividends paid									(3,800,000)	0	0
Net increase (decrease) in advances from affiliate									0	0	0
Net cash (used in) provided by continuing financing activities									(81,700,000)	169,700,000	(10,300,000)
Net (decrease) increase in cash and cash equivalents from continuing operations									(70,000,000)	13,100,000	79,500,000
Cash flows from discontinued operations - operating activities									(17,700,000)	(5,400,000)	62,100,000
Cash flows from discontinued operations - investing activities									(6,900,000)	(13,300,000)	(29,900,000)
Net Cash Provided by (Used in) Discontinued Operations									(24,600,000)	(18,700,000)	32,200,000
Net (decrease) increase in cash and cash equivalents									(94,600,000)	(5,600,000)	111,700,000
Cash and cash equivalents at beginning of year				233,600,000				239,200,000	233,600,000	239,200,000	127,500,000
Cash and cash equivalents at end of year	139,000,000				233,600,000				139,000,000	233,600,000	239,200,000
Issuer
Cash Flows from Continuing Operating Activities:
Net (loss) income									(126,100,000)	25,000,000	98,800,000
Adjustments to reconcile net income to net cash provided by continuing operating activities:
(Loss) income from discontinued operations, net of tax									0	0	0
Asset impairment									0
Depreciation and amortization expense									0	0	0
Deferred income tax expense (benefit)									6,800,000	0	(1,000,000)
Payments in Excess of Expense for Retirement Plans									0	0	0
Share-based compensation expense									9,800,000	7,600,000	6,700,000
Equity in Earnings of Subsidiaries									101,300,000	(56,200,000)	(138,900,000)
Excess tax benefit from share-based awards									(400,000)
Loss from equity method investment									0	0
Loss on extinguishment/modification of debt									0
Changes in working capital pertaining to continuing operating activities (net of acquisitions):
Receivables									(100,000)	0	0
Inventories									0	0	0
Accounts payable									0	(600,000)	500,000
Accrued liabilities									(500,000)	0	0
Interest payable									(6,000,000)	(2,100,000)	(200,000)
Income taxes									12,300,000	(23,500,000)	(17,200,000)
Accrual for black lung benefits									0	0	0
Other									6,100,000	7,100,000	(4,900,000)
Net cash provided by continuing operating activities									3,200,000	(42,700,000)	(56,200,000)
Cash Flows from Continuing Investing Activities:
Capital expenditures									0	0	0
Acquisition of businesses, net of cash acquired										0
Net cash used in continuing investing activities									0	0	0
Cash Flows from Continuing Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs									0	0
Proceeds from issuance of long-term debt									0	0
Repayment of long-term debt									0	0	(3,300,000)
Debt issuance costs									0	(1,600,000)
Proceeds from revolving facility									0	0
Repayment of revolving facility									0
Cash distributions to noncontrolling interests									0	0	0
Shares repurchased									(85,100,000)	(10,900,000)	(9,400,000)
Proceeds from exercise of stock options									2,900,000	2,500,000	4,700,000
Excess tax benefit from share-based awards									300,000
Dividends paid									(3,800,000)
Net increase (decrease) in advances from affiliate									82,500,000	52,700,000	64,200,000
Net cash (used in) provided by continuing financing activities									(3,200,000)	42,700,000	56,200,000
Net (decrease) increase in cash and cash equivalents from continuing operations									0	0	0
Cash flows from discontinued operations - operating activities									0	0	0
Cash flows from discontinued operations - investing activities									0	0	0
Net Cash Provided by (Used in) Discontinued Operations									0	0	0
Net (decrease) increase in cash and cash equivalents									0	0	0
Cash and cash equivalents at beginning of year				0				0	0	0	0
Cash and cash equivalents at end of year	0				0				0	0	0
Guarantor Subsidiaries
Cash Flows from Continuing Operating Activities:
Net (loss) income									(58,800,000)	64,500,000	148,500,000
Adjustments to reconcile net income to net cash provided by continuing operating activities:
(Loss) income from discontinued operations, net of tax									106,000,000	15,500,000	(20,500,000)
Asset impairment									16,800,000
Depreciation and amortization expense									25,500,000	25,200,000	22,300,000
Deferred income tax expense (benefit)									(14,300,000)	500,000	(7,900,000)
Payments in Excess of Expense for Retirement Plans									(8,100,000)	(5,300,000)	(9,600,000)
Share-based compensation expense									0	0	0
Equity in Earnings of Subsidiaries									(56,000,000)	(88,600,000)	(95,500,000)
Excess tax benefit from share-based awards									100,000
Loss from equity method investment									0	0
Loss on extinguishment/modification of debt									0
Changes in working capital pertaining to continuing operating activities (net of acquisitions):
Receivables									24,100,000	(23,600,000)	(7,800,000)
Inventories									(1,800,000)	14,800,000	35,500,000
Accounts payable									(3,600,000)	4,200,000	(55,900,000)
Accrued liabilities									(19,100,000)	(6,100,000)	12,800,000
Interest payable									7,300,000	(7,300,000)	7,300,000
Income taxes									(17,900,000)	26,400,000	(1,100,000)
Accrual for black lung benefits									11,500,000	(2,400,000)	1,300,000
Other									200,000	4,100,000	(17,000,000)
Net cash provided by continuing operating activities									11,900,000	21,900,000	12,400,000
Cash Flows from Continuing Investing Activities:
Capital expenditures									(12,600,000)	(19,800,000)	(20,900,000)
Acquisition of businesses, net of cash acquired										0
Net cash used in continuing investing activities									(12,600,000)	(19,800,000)	(20,900,000)
Cash Flows from Continuing Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs									0	0
Proceeds from issuance of long-term debt									0	0
Repayment of long-term debt									0	0	0
Debt issuance costs									0	0
Proceeds from revolving facility									0	0
Repayment of revolving facility									0
Cash distributions to noncontrolling interests									0	0	0
Shares repurchased									0	0	0
Proceeds from exercise of stock options									0	0	0
Excess tax benefit from share-based awards									0
Dividends paid									0
Net increase (decrease) in advances from affiliate									(57,000,000)	(5,600,000)	73,800,000
Net cash (used in) provided by continuing financing activities									(57,000,000)	(5,600,000)	73,800,000
Net (decrease) increase in cash and cash equivalents from continuing operations									(57,700,000)	(3,500,000)	65,300,000
Cash flows from discontinued operations - operating activities									(17,700,000)	(5,400,000)	62,100,000
Cash flows from discontinued operations - investing activities									(6,900,000)	(13,300,000)	(29,900,000)
Net Cash Provided by (Used in) Discontinued Operations									(24,600,000)	(18,700,000)	32,200,000
Net (decrease) increase in cash and cash equivalents									(82,300,000)	(22,200,000)	97,500,000
Cash and cash equivalents at beginning of year				184,700,000				206,900,000	184,700,000	206,900,000	109,400,000
Cash and cash equivalents at end of year	102,400,000				184,700,000				102,400,000	184,700,000	206,900,000
Non- Guarantor Subsidiaries
Cash Flows from Continuing Operating Activities:
Net (loss) income									37,800,000	105,400,000	89,600,000
Adjustments to reconcile net income to net cash provided by continuing operating activities:
(Loss) income from discontinued operations, net of tax									0	0	0
Asset impairment									0
Depreciation and amortization expense									70,600,000	51,900,000	42,700,000
Deferred income tax expense (benefit)									1,500,000	0	39,300,000
Payments in Excess of Expense for Retirement Plans									0	(100,000)	0
Share-based compensation expense									0	0	0
Equity in Earnings of Subsidiaries									0	0	0
Excess tax benefit from share-based awards									0
Loss from equity method investment									35,000,000	2,200,000
Loss on extinguishment/modification of debt									15,400,000
Changes in working capital pertaining to continuing operating activities (net of acquisitions):
Receivables									(14,100,000)	6,500,000	2,100,000
Inventories									(8,700,000)	16,100,000	22,300,000
Accounts payable									(23,900,000)	21,600,000	(13,800,000)
Accrued liabilities									1,700,000	(16,700,000)	(1,800,000)
Interest payable									400,000	11,900,000	(7,300,000)
Income taxes									6,600,000	(13,000,000)	700,000
Accrual for black lung benefits									0	0	0
Other									(7,400,000)	(8,300,000)	14,000,000
Net cash provided by continuing operating activities									114,900,000	177,500,000	187,800,000
Cash Flows from Continuing Investing Activities:
Capital expenditures									(105,700,000)	(112,500,000)	(33,300,000)
Acquisition of businesses, net of cash acquired										(113,300,000)
Equity method investment in VISA SunCoke Limited										(67,700,000)
Net cash used in continuing investing activities									(105,700,000)	(293,500,000)	(33,300,000)
Cash Flows from Continuing Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs									90,500,000	237,800,000
Proceeds from issuance of long-term debt									268,100,000	150,000,000
Repayment of long-term debt									(276,500,000)	(225,000,000)	0
Debt issuance costs									(5,800,000)	(5,300,000)
Proceeds from revolving facility									40,000,000	40,000,000
Repayment of revolving facility									(80,000,000)
Cash distributions to noncontrolling interests									(32,300,000)	(17,800,000)	(2,300,000)
Shares repurchased									0	0	0
Proceeds from exercise of stock options									0	0	0
Excess tax benefit from share-based awards									0
Dividends paid									0
Net increase (decrease) in advances from affiliate									(25,500,000)	(47,100,000)	(138,000,000)
Net cash (used in) provided by continuing financing activities									(21,500,000)	132,600,000	(140,300,000)
Net (decrease) increase in cash and cash equivalents from continuing operations									(12,300,000)	16,600,000	14,200,000
Cash flows from discontinued operations - operating activities									0	0	0
Cash flows from discontinued operations - investing activities									0	0	0
Net Cash Provided by (Used in) Discontinued Operations									0	0	0
Net (decrease) increase in cash and cash equivalents									(12,300,000)	16,600,000	14,200,000
Cash and cash equivalents at beginning of year				48,900,000				32,300,000	48,900,000	32,300,000	18,100,000
Cash and cash equivalents at end of year	36,600,000				48,900,000				36,600,000	48,900,000	32,300,000
Combining and Consolidating Adjustments
Cash Flows from Continuing Operating Activities:
Net (loss) income									45,300,000	(144,800,000)	(234,400,000)
Adjustments to reconcile net income to net cash provided by continuing operating activities:
(Loss) income from discontinued operations, net of tax									0	0	0
Asset impairment									0
Depreciation and amortization expense									0	0	0
Deferred income tax expense (benefit)									0	0	0
Payments in Excess of Expense for Retirement Plans									0	0	0
Share-based compensation expense									0	0	0
Equity in Earnings of Subsidiaries									(45,300,000)	144,800,000	234,400,000
Excess tax benefit from share-based awards									0
Loss from equity method investment									0	0
Loss on extinguishment/modification of debt									0
Changes in working capital pertaining to continuing operating activities (net of acquisitions):
Receivables									0	0	0
Inventories									0	0	0
Accounts payable									0	0	0
Accrued liabilities									0	0	0
Interest payable									0	0	0
Income taxes									0	0	0
Other									0	0	0
Net cash provided by continuing operating activities									0	0	0
Cash Flows from Continuing Investing Activities:
Capital expenditures									0	0	0
Acquisition of businesses, net of cash acquired										0
Net cash used in continuing investing activities									0	0	0
Cash Flows from Continuing Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs									0	0
Proceeds from issuance of long-term debt									0	0
Repayment of long-term debt									0	0	0
Debt issuance costs									0	0
Proceeds from revolving facility									0	0
Repayment of revolving facility									0
Cash distributions to noncontrolling interests									0	0	0
Shares repurchased									0	0	0
Proceeds from exercise of stock options									0	0	0
Excess tax benefit from share-based awards									0
Dividends paid									0
Net increase (decrease) in advances from affiliate									0	0	0
Net cash (used in) provided by continuing financing activities									0	0	0
Net (decrease) increase in cash and cash equivalents from continuing operations									0	0	0
Cash flows from discontinued operations - operating activities									0	0	0
Cash flows from discontinued operations - investing activities									0	0	0
Net Cash Provided by (Used in) Discontinued Operations									0	0	0
Net (decrease) increase in cash and cash equivalents									0	0	0
Cash and cash equivalents at beginning of year				0				0	0	0	0
Cash and cash equivalents at end of year	$ 0				$ 0				$ 0	$ 0	$ 0