Debt (First Lien Notes) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term Debt	$ 11,475	$ 11,112
First Lien Notes 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt	320	320
First Lien Notes 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt	875	875
First Lien Notes 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt	1,600	1,600
2022 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	744	744
First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	960	960
2024 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	490	490
Corporate Debt Securities [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 4,989	$ 4,989