Statement of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014
Interest paid
Cash paid for interest, net of interest capitalized		$ 60.9	$ 65.9
Payment of reorganization items		1.5
Noncash investing and financing
Accrued and payable capital expenditures		33.1	116.8
Accrued debt issuance costs			$ 1.4
New Revolving Credit Facility
Noncash investing and financing
Offset of proceeds from terminations	$ 70.8	$ 70.8