v3.6.0.2

Debt Debt (First Lien Notes) (Details) - USD ($)
$ in Millions

3 Months Ended

12 Months Ended

Mar. 31, 2017

Dec. 31, 2016

Mar. 31, 2015

Dec. 31, 2016

Dec. 31, 2015

Dec. 31, 2014

Jun. 30, 2016

Debt Instrument [Line Items]

Gains (Losses) on Extinguishment of Debt

$ (25)

$ (40)

$ (346)

Long-term Debt

$ 12,046

12,046

11,292

Debt Issuance Costs, Net

154

154

Long-term Debt, Gross

12,369

12,369

2022 First Lien Notes [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 739

$ 739

$ 737

Debt Instrument, Interest Rate, Effective Percentage

^[1]

6.40%

6.40%

6.40%

First Lien Notes 2023 [Member]

Debt Instrument [Line Items]

Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed

10.00%

Gains (Losses) on Extinguishment of Debt

$ (5)

$ (19)

Long-term Debt

^[2],[3]

$ 450

$ 450

$ 568

Debt Instrument, Interest Rate, Effective Percentage

^[1]

8.10%

8.10%

8.10%

2024 First Lien Notes [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 485

$ 485

$ 484

Debt Instrument, Interest Rate, Effective Percentage

^[1]

6.10%

6.10%

6.10%

2026 First Lien Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Face Amount

$ 625

Long-term Debt

$ 616

$ 616

$ 0

Debt Instrument, Interest Rate, Effective Percentage

^[1]

5.40%

5.40%

0.00%

Debt Instrument, Interest Rate, Stated Percentage

5.25%

Debt Issuance Costs, Net

$ 9

Corporate Debt Securities [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 2,290

$ 2,290

$ 1,789

Subsequent Event [Member] | First Lien Notes 2023 [Member]

Debt Instrument [Line Items]

Gains (Losses) on Extinguishment of Debt

$ (21)

Subsequent Event [Member] | New 2019 First Lien Term Loan [Member]

Debt Instrument [Line Items]

Debt Instrument, Face Amount

400

Debt Issuance Costs, Net

8

Early Redemption Amount [Member] | First Lien Notes 2023 [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 147

Early Redemption Amount [Member] | Subsequent Event [Member] | First Lien Notes 2023 [Member]

Debt Instrument [Line Items]

Long-term Debt, Gross

$ 453

London Interbank Offered Rate (LIBOR) [Member] | Subsequent Event [Member] | New 2019 First Lien Term Loan [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.75%

[1]	Our weighted average interest rate calculation includes the amortization of debt issuance costs and debt discount.
[2]	In December 2016, we used cash on hand to redeem 10% of the original aggregate principal amount of our 2023 First Lien Notes, plus accrued and unpaid interest. During the fourth quarter of 2016, we recorded approximately $5 million in debt extinguishment costs related to the partial repurchase of our 2023 First Lien Notes.
[3]	On February 3, 2017, we issued a notice of redemption to repay the remaining $453 million of our outstanding 2023 First Lien Notes using cash on hand along with the proceeds from the New 2019 First Lien Term Loan which contains a substantially lower variable rate of LIBOR plus 1.75% per annum.

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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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