Commitments And Contingencies (Guarantees And Indemnifications) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
New Zealand [Member]
Guarantees and Indemnifications, Disposal Date	Fourth quarter of 2006
Guarantees and Indemnifications, Maximum Limit	$ 163	[1]
Guarantees and Indemnifications, Expiration Date	March 2012
Mexico [Member]
Guarantees and Indemnifications, Disposal Date	Second quarter of 2007
Guarantees and Indemnifications, Maximum Limit	$ 20
Guarantees and Indemnifications, Expiration Date	June 2012

[1] Based on exchange rate at Dec. 31, 2011