v3.8.0.1

Debt (First Lien Notes) (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term Debt		$ 11,484			$ 11,484		$ 12,046
Gain (Loss) on Extinguishment of Debt		1		$ 0	26	$ 15
2022 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		741			741		739
First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]	0			0		450
Gain (Loss) on Extinguishment of Debt			$ 21
New 2019 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt		389			389		0
2024 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		485			485		485
2026 First Lien Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		617			617		616
Corporate Debt Securities [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 1,843			$ 1,843		$ 2,290
Early Redemption Amount [Member] | First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 453
[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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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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-Publisher FASB
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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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