Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Statement of Other Comprehensive Income [Abstract]
Net Income	$ 127	$ 104	$ 224	$ 189
Other comprehensive income (loss), net of tax:
Benfit obligations, net of taxes	1	0	2	1
Comprehensive income	$ 128	$ 104	$ 226	$ 190

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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