Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Flows from Operating Activities:
Net income (loss)	$ 10.3	$ (101.8)	$ 50.1
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Asset and goodwill impairment	0.0	150.3	0.0
Loss from equity method investment	21.6	35.0	2.2
Depreciation and amortization expense	109.1	106.3	96.0
Deferred income tax (benefit) expense	(5.6)	(64.4)	1.6
Settlement loss and payments in excess of expense for pension plan	13.1	(7.5)	(0.1)
Gain on curtailment and payments in excess of expense for postretirement plan benefits	(8.0)	(0.6)	(5.3)
Share-based compensation expense	7.2	9.8	7.6
Excess tax benefit from share-based awards	0.0	(0.3)	0.0
Loss on extinguishment of debt	0.5	15.4	0.0
Changes in working capital pertaining to operating activities (net of acquisitions):
Receivables	18.8	13.3	(18.1)
Inventories	23.2	(12.6)	29.2
Accounts payable	(17.9)	(33.0)	20.0
Accrued liabilities	(28.7)	(8.0)	(24.7)
Interest payable	(1.0)	1.7	2.5
Income taxes	(5.6)	1.0	(10.2)
Accrual for black lung benefits	6.0	11.5	(2.4)
Other	(1.9)	(3.8)	2.9
Net cash provided by operating activities	141.1	112.3	151.3
Cash Flows from Investing Activities:
Capital expenditures	(75.8)	(125.2)	(145.6)
Acquisition of businesses, net of cash received	(191.7)	0.0	(113.3)
Restricted cash	(17.7)	0.0	0.0
Equity method investment in VISA SunCoke Limited	0.0		(67.7)
Net cash used in investing activities	(285.2)	(125.2)	(326.6)
Cash Flows from Financing Activities:
Proceeds from issuance of common units of SunCoke Energy Partners, L.P., net of offering costs	0.0	90.5	237.8
Proceeds from issuance of long-term debt	260.8	268.1	150.0
Repayment of long-term debt	(248.1)	(276.5)	(225.0)
Debt issuance costs	(5.7)	(5.8)	(6.9)
Proceeds from revolving facility	292.4	40.0	40.0
Repayment of revolving facility	(50.0)	(80.0)	0.0
Cash distributions to noncontrolling interests	(43.3)	(32.3)	(17.8)
Shares repurchased	(35.7)	(85.1)	(10.9)
SunCoke Energy Partners, L.P. units repurchased	(12.8)	0.0	0.0
Proceeds from exercise of stock options, net of shares withheld for taxes	(1.1)	2.9	2.5
Excess tax benefit from share-based awards		0.3	0.0
Dividends paid	(28.0)	(3.8)	0.0
Net cash provided by (used in) financing activities	128.5	(81.7)	169.7
Net decrease in cash and cash equivalents	(15.6)	(94.6)	(5.6)
Cash and cash equivalents at beginning of year	139.0	233.6	239.2
Cash and cash equivalents at end of year	123.4	139.0	233.6
Supplemental Disclosure of Cash Flow Information
Interest paid	58.1	45.8	43.2
Income taxes paid, net of refunds of, $1.5 million and $4.6 million in 2015 and 2014, respectively, and no refunds in 2013.	2.4	9.1	15.3
Tax refunds	$ 1.5	$ 4.6	$ 0.0