DEBT (Tables)

12 Months Ended

Dec. 31, 2016

Debt Instruments [Abstract]

Schedule of long-term debt

	December 31,
	2016			2015
Notes payable:	($ in millions)
Variable-rate Senior Term Loan facility, due 2020 (2.77% and 2.17% at December 31, 2016 and 2015, respectively)	$	1,282.5		$	1,350.0
Variable-rate Sumitomo credit facility, due 2018 (2.27% and 1.77% at December 31, 2016 and 2015, respectively)	590.0			800.0
Variable-rate Recovery Zone bonds, due 2024-2035 (2.47% and 1.40% at December 31, 2016 and 2015, respectively)	103.0			103.0
Variable-rate Go Zone bonds, due 2024 (2.47% and 1.40% at December 31, 2016 and 2015, respectively)	50.0			50.0
Variable-rate Industrial development and environmental improvement obligations, due 2025 (0.25% and 0.27% at December 31, 2016 and 2015, respectively)	2.9			2.9
9.75%, due 2023	720.0			720.0
10.00%, due 2025	500.0			500.0
5.50%, due 2022	200.0			200.0
6.75%, due 2016	—			125.0
7.23%, SunBelt Notes due 2013-2017	12.2			24.4
Receivables financing agreement	210.0			—
Capital lease obligations	3.9			4.6
Total notes payable	3,674.5			3,879.9
Deferred debt issuance costs and unamortized fair value premium	(28.5		)	(32.7		)
Interest rate swaps	(28.4		)	1.6
Total debt	3,617.6			3,848.8
Amounts due within one year	80.5			205.0
Total long-term debt	$	3,537.1		$	3,643.8