CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 54.8	$ 45.3
Accounts receivable, net	596.2	525.2
Inventory, net	738.3	586.6
Deferred tax assets, current	63.9	69.6
Other current assets	52.8	46.5
Total current assets	1,506.0	1,273.2
Property, plant and equipment	5,893.6	5,871.9
Accumulated depreciation	(4,088.3)	(3,991.8)
Property, plant and equipment, net	1,805.3	1,880.1
Other non-current assets:
Investment in Magnetation LLC	229.0	187.8
Other non-current assets	266.3	264.6
TOTAL ASSETS	3,806.6	3,605.7
Current liabilities:
Accounts payable	642.4	601.8
Accrued liabilities	170.2	142.9
Current portion of long-term debt	0.4	0.8
Current portion of pension and other postretirement benefit obligations	69.5	85.9
Total current liabilities	882.5	831.4
Non-current liabilities:
Long-term debt	1,948.2	1,506.2
Pension and other postretirement benefit obligations	816.3	965.4
Other non-current liabilities	115.3	110.0
TOTAL LIABILITIES	3,762.3	3,413.0
Equity:
Common stock, authorized 300,000,000 shares of $0.01 par value each; issued 136,936,413 and 149,691,388 shares in 2014 and 2013; outstanding 136,793,421 and 136,380,078 shares in 2014 and 2013	1.4	1.5
Additional paid-in capital	1,910.9	2,079.2
Treasury stock, common shares at cost, 142,992 and 13,311,310 shares in 2014 and 2013	(1.0)	(174.0)
Accumulated deficit	(2,554.3)	(2,451.1)
Accumulated other comprehensive income	272.0	323.4
Total stockholders' equity (deficit)	(371.0)	(221.0)
Noncontrolling interests	415.3	413.7
TOTAL EQUITY	44.3	192.7
TOTAL LIABILITIES AND EQUITY	3,806.6	3,605.7
Variable Interest Entity, Primary Beneficiary [Member] | SunCoke Middletown [Member]
Current assets:
Cash and cash equivalents	17.6	14.2
Inventory, net	24.7	22.1
Property, plant and equipment	418.9	418.5
Accumulated depreciation	(36.1)	(29.0)
Other assets (liabilities), net	(0.8)	(0.7)
Current liabilities:
Accounts payable	10.9	13.3
Equity:
Noncontrolling interests	413.4	411.8
Variable Interest Entity, Primary Beneficiary [Member] | Other Variable Interest Entities [Member]
Current assets:
Cash and cash equivalents	0.8	1.0
Property, plant and equipment	11.3	11.5
Accumulated depreciation	(9.1)	(9.2)
Other assets (liabilities), net	0.7	0.6
Equity:
Noncontrolling interests	$ 1.9	$ 1.9