Significant Non-Cash Investing Activities (Details) (USD $) In Millions	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Significant Non Cash Investing Activities [Abstract]
Grant receivables from outside parties for capital expenditures	$ 15.2	$ 10.8
Purchases of property and equipment accrued in accounts payable	$ 16.3	$ 12.4