Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Income Taxes (Textual) [Abstract]
Income tax (benefit) expense	$ (2)		$ 1		$ (2)
Valuation allowance						1,042
Approximate federal net operating loss carryforwards	1,978			1,978
Federal net operating loss carryforwards, expiration dates				2026 through 2032
Approximate federal alternative minimum tax credit carryforwards	49			49
Minimum taxable income needed to fully realize the U.S. federal net deferred tax assets	2,118			2,118
Foreign tax credit carryforwards	8			8
Foreign tax credit carryforwards, expiration date				Dec. 31, 2015
Approximate gross deferred tax assets operating loss and tax credit carry forwards that will expire in current year	1			1
Gross deferred tax assets related to state NOLs and tax credit carryforwards, expiration dates				2013 through 2032
Deferred tax assets operating loss tax carryforwards	271			271
Deferred tax assets, operating loss and tax credit carryforwards foreign	4			4
Valuation Allowance increased to				1,077
Increase in Valuation Allowance Impacted by current loss				40
Additional valuation allowance against deferred tax assets recorded	21	14
Decreased in deferred tax assets valuation allowance	5			5
Percentage of change in ownership				50.00%
Period of change in ownership				3 years
Long-term tax-exempt rate	3.26%			3.26%
Time period after the change in which amount of the limitation be increased or decreased by built-in gains or losses				5 years
Approximate annual NOL utilization had an ownership change occurred	67			67
Effective income tax rate	3.40%
Noncash income tax benefit on the loss from continuing operations	$ 4		$ 3