Statement of Cash Flows (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accrued capital expenditures	$ 56.2	$ 16.1	$ 8.6
Notes Payable	7.5
Capitalized and deferred interest	6.2	1.9	0
Facilities Building D and E
Facility lease obligations recognized	127.8	25.0	0
Warrant Transactions
Accounts Payable, Other	59.8
Liabilities, Fair Value Adjustment	$ 87.5