CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 1,934.1	$ 2,274.9
Restricted cash	74.2
Accounts receivable - net	294.3	217.4
Inventories - net	321.0	277.9
Prepaid income taxes	24.5
Deferred income taxes	44.9	9.5
Other	26.5	27.9
Total current assets	2,719.5	2,807.6
Property, plant and equipment, net of accumulated depreciation, depletion and amortization of $2,899.7 and $2,757.1	4,086.5	3,900.5
Asset retirement obligation funds	200.8	200.8
Investments in and advances to affiliates	898.6	935.6
Goodwill	2,064.5	2,064.5
Other assets	281.7	257.9
Total assets	10,251.6	10,166.9
Current liabilities:
Accounts payable and accrued expenses	489.9	366.5
Income taxes payable	15.9	187.1
Customer advances	67.7	380.7
Notes payable		5.0
Distributions payable to noncontrolling interest		5.3
Other	3.6	5.6
Total current liabilities	577.1	950.2
Long-term debt	3,098.0	1,600.0
Deferred income taxes	783.2	938.8
Other noncurrent liabilities	449.9	395.7
Contingencies (Note 18)
Stockholders' equity:
Preferred stock - $0.01 par value, 50,000,000 shares authorized
Common stock - $0.01 par value, 500,000,000 shares authorized, 2013 - 59,305,690 shares issued and 2012 - 62,961,628 shares issued	0.6	0.6
Paid-in capital	1,653.5	2,492.4
Retained earnings	3,673.1	3,461.1
Treasury stock - at cost, 2013 - 1,274,837 shares and 2012 - 10,940 shares	(233.3)	(2.3)
Accumulated other comprehensive loss	(115.3)	(49.6)
Total stockholders' equity	4,978.6	5,902.2
Noncontrolling interest	364.8	380.0
Total equity	5,343.4	6,282.2
Total liabilities and equity	$ 10,251.6	$ 10,166.9