v3.7.0.1

Debt (First Lien Notes) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term Debt		$ 11,943	$ 12,046
2022 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		739	739
First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]	0	450
New 2019 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		400
Long-term Debt		389	0
Debt Issuance Costs, Net		8
2024 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		485	485
2026 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		617	616
Corporate Debt Securities [Member]
Debt Instrument [Line Items]
Long-term Debt		1,841	$ 2,290
Early Redemption Amount [Member] | First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 453
London Interbank Offered Rate (LIBOR) [Member] | New 2019 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.75%
[1] On March 6, 2017, we used cash on hand along with the proceeds from our 2019 First Lien Term Loan to redeem the remaining $453 million of our 2023 First Lien Notes, plus accrued and unpaid interest. During the first quarter of 2017, we recorded approximately $21 million in debt extinguishment costs related to the redemption of our 2023 First Lien Notes.

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