Pension and Postretirement Benefit Plans (Details Textual) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Pension And Postretirement Benefit Plans (Details Textuals) [Abstract]
Contribution to pension and postretirement benefit plans	$ 2	$ 4
Expectation to contribute to pension and postretirement benefit plans	$ 6	$ 6

The amount of contributions made by the employer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph b

Name:	us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration