Leases Leases (Tables)

12 Months Ended

Dec. 31, 2015

Operating Leased Assets [Line Items]

Leases And Royalty Future Minimum Payments [Table Text Block]

Future minimum lease and royalty payments as of December 31, 2015 are as follows:

	Capital Leases		Operating Leases		Coal Lease and Royalty Obligations
Year Ending December 31,
	(Dollars in millions)
2016	$	12.9	$	191.5	$	254.3
2017	7.3		173.8		20.3
2018	8.8		109.4		19.9
2019	0.5		64.2		19.4
2020	0.5		23.4		18.9
2021 and thereafter	10.1		36.5		30.8
Total minimum lease payments	40.1		$	598.8	$	363.6
Less interest	9.8
Present value of minimum capital lease payments	$	30.3