Debt Obligations 2017 Refinancing Transactions (Details) - USD ($)	3 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Write off of Deferred Debt Issuance Cost	$ 3
Long-term debt	3,470,000,000	$ 3,397,000,000
13.75% Senior Secured Notes due 2022 [Member]
Debt Instrument [Line Items]
Long-term debt	225,000,000	0
10.375% First-Priority Senion Secured Notes due 2022 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 485,000,000	$ 0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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