Inventories (Tables)

6 Months Ended

Jun. 30, 2018

Inventory Disclosure [Abstract]

Components of Inventories

The components of inventories were as follows:

	June 30, 2018		December 31, 2017
	(Dollars in millions)
Coal	$	70.1	$	61.4
Coke	7.4		12.3
Materials, supplies and other	38.9		37.3
Total inventories	$	116.4	$	111.0