Guarantor Consolidating Financial Statements - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Due To Affiliates [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	$ 2,000
Parent Company [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	3,100	$ 1,500
Guarantor Subsidiaries [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	1,400	1,000
Guarantor Subsidiaries [Member] | Due From Affiliates [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	$ 443	$ 159