Stockholders' Equity (Narratives) (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2009	Dec. 31, 2011
Acquired ownership interest	31.00%
Acquisition of Andean subsidiary	$ 289,000,000
Equity transaction that reduced non-controlling interest	278,000,000
Increased investments in equity companies	11,000,000
Unrecognized prior service cost		6,000,000
Unrecognized net actuarial loss		109,000,000
Unremitted net income of equity companies		$ 1,000,000,000