Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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No definition available.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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.

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No definition available.

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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 4
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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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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)
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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Long-Term Debt - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			12 Months Ended
	Mar. 31, 2007	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2015	Oct. 31, 2014	Jan. 01, 2014	Dec. 31, 2011
Long-term debt
Total Debt Obligations		$ 11,025		$ 11,366	$ 11,025
Total Unamortized (Discount) Premium		(16)		(33)	(16)
Less current portion		(15)		(349)	(15)
Long-Term Debt, less current portion		10,994		10,984	10,994
TrancheBIII2019TermLoan [Member]
Long-term debt
Total Debt Obligations		815		815	815
Senior Notes 5point 125Percent Due 2023 [Member]
Long-term debt
Total Debt Obligations		700		0	700
Senior Notes 5point 375Percent Due 2025 [Member]
Long-term debt
Total Debt Obligations		800		0	800
Senior Notes 5.375 Percent Due 2024 [Member]
Long-term debt
Total Debt Obligations		900		0	900
TrancheB2020TermLoanTotal [Member]
Long-term debt
Total Debt Obligations		1,796		1,796	$ 1,796
Tranche B 2022 Term Loans [Member]
Long-term debt
Debt Instrument, Interest Rate Terms					LIBOR +3.50%
Total Debt Obligations		$ 0		$ 2,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage				4.50%
2.0 Billion Tranche B-II 2022 Term Loan [Member]
Long-term debt
Debt Instrument, Interest Rate Terms		LIBOR +2.75%
Total Debt Obligations		$ 2,000		$ 0	$ 2,000
Debt Instrument, Interest Rate, Stated Percentage		3.50%			3.50%
Floating Rate Senior Notes due 2015
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		3.846%			3.846%			3.826%
Floating Rate Senior Notes due 2018 [Member]
Long-term debt
Debt Instrument, Interest Rate Terms		6-Month LIBOR +3.50%
Total Debt Obligations		$ 300		$ 300	$ 300
Debt Instrument, Interest Rate, Stated Percentage		4.101%		3.826%	4.101%
Senior Notes 11 Point 875 Percent Due 2019 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		11.875%			11.875%
Senior Notes due 2019 (9.375%)
Long-term debt
Total Debt Obligations		$ 0		$ 500	$ 0
Debt Instrument, Interest Rate, Stated Percentage		9.375%			9.375%
Senior Notes due 2019 (8.125%)
Long-term debt
Total Debt Obligations		$ 0		1,200	$ 0
Debt Instrument, Interest Rate, Stated Percentage		8.125%			8.125%
Senior Notes due 2019 (8.875%)
Long-term debt
Total Debt Obligations		$ 0		300	$ 0
Debt Instrument, Interest Rate, Stated Percentage		8.875%			8.875%
Senior Notes 5point75Percent Due 2022 [Member]
Long-term debt
Total Debt Obligations		$ 600		600	$ 600
Senior Notes 8 Point 625 Percent Due 2020 [Member]
Long-term debt
Total Debt Obligations		$ 0		900	$ 0
Debt Instrument, Interest Rate, Stated Percentage		8.625%			8.625%
Senior Notes due 2020 (7.0%)
Long-term debt
Total Debt Obligations		$ 775		775	$ 775
Senior Notes due 2021 (6.125%)
Long-term debt
Total Debt Obligations		$ 640		640	$ 640
Senior Notes 5.375percent Due 2022 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.375%			5.375%
5point375SeniorNotesdue2022 [Member]
Long-term debt
Total Debt Obligations		$ 1,000		1,000	$ 1,000
Senior Notes 5point 625Percent Due 2023 [Member]
Long-term debt
Total Debt Obligations		500		0	500
Convertible Senior Notes 7 Percent Due 2015 [Member]
Long-term debt
Total Debt Obligations		0		58	0
Convertible Senior Notes due 2015 Series B (7.0%)
Long-term debt
Total Debt Obligations		0		275	0
Capital Leases
Long-term debt
Total Debt Obligations		$ 199		207	$ 199
Tranche B 2016 Term Loan [Member]
Long-term debt
Debt Instrument, Description of Variable Rate Basis					LIBOR
Tranche B 2019 Term Loan [Member]
Long-term debt
Debt Instrument, Description of Variable Rate Basis					LIBOR
TrancheBII2019TermLoan [Member]
Long-term debt
Debt Instrument, Description of Variable Rate Basis					LIBOR
Level 3 Financing [Member]
Long-term debt
Debt Instrument, Description of Variable Rate Basis	three month LIBOR				three month LIBOR
Level 3 Financing [Member] \| Senior Notes 5point 125Percent Due 2023 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.125%			5.125%
Level 3 Financing [Member] \| Senior Notes 5point 375Percent Due 2025 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.375%			5.375%
Level 3 Financing [Member] \| Senior Notes 5point 375Percent Due 2024 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.375%			5.375%
Level 3 Financing [Member] \| Senior Notes due 2019 (9.375%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		9.375%			9.375%
Level 3 Financing [Member] \| Senior Notes due 2019 (8.125%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		8.125%			8.125%
Level 3 Financing [Member] \| Senior Notes 8 Point 625 Percent Due 2020 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		8.625%			8.625%
Level 3 Financing [Member] \| Senior Notes due 2020 (7.0%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		7.00%			7.00%
Level 3 Financing [Member] \| Senior Notes due 2021 (6.125%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		6.125%			6.125%
Level 3 Financing [Member] \| Senior Notes 5.375percent Due 2022 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.375%			5.375%
Level 3 Financing [Member] \| Senior Notes 5point 625Percent Due 2023 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.625%			5.625%
Guarantor Subsidiaries [Member]
Long-term debt
Less current portion		$ 0		0	$ 0
Long-Term Debt, less current portion		$ 10,210		9,893	10,210
Guarantor Subsidiaries [Member] \| TrancheBIII2019TermLoan [Member]
Long-term debt
Debt Instrument, Interest Rate Terms		LIBOR +3.00%
Guarantor Subsidiaries [Member] \| TrancheB2020TermLoanTotal [Member]
Long-term debt
Debt Instrument, Interest Rate Terms		LIBOR +3.00%
Total Debt Obligations							$ 1,796
Level 3 Communications, Inc.
Long-term debt
Less current portion		$ 0		(333)	0
Long-Term Debt, less current portion		$ 600		$ 900	$ 600
Level 3 Communications, Inc. \| Senior Notes 11 Point 875 Percent Due 2019 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		11.875%			11.875%
Level 3 Communications, Inc. \| Senior Notes due 2019 (8.875%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		8.875%			8.875%
Level 3 Communications, Inc. \| Senior Notes 5point75Percent Due 2022 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		5.75%			5.75%
Level 3 Communications, Inc. \| Convertible Senior Notes 7 Percent Due 2015 [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		7.00%			7.00%
Level 3 Communications, Inc. \| Convertible Senior Notes due 2015 Series B (7.0%)
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage		7.00%			7.00%
London Interbank Offered Rate (LIBOR) [Member] \| Level 3 Financing [Member] \| 2.0 Billion Tranche B-II 2022 Term Loan [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum			0.75%
Debt Instrument, Description of Variable Rate Basis		LIBOR	LIBOR	LIBOR
London Interbank Offered Rate (LIBOR) [Member] \| Level 3 Financing [Member] \| Tranche B-III 2019, Tranche B 2020 and Tranche B 2022 Term Loans [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum					1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Guarantor Subsidiaries [Member] \| Tranche B-III 2019, Tranche B 2020 and Tranche B 2022 Term Loans [Member]
Long-term debt
Debt Instrument, Description of Variable Rate Basis			LIBOR
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Guarantor Subsidiaries [Member] \| Tranche B 2022 Term Loans [Member]
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage						1.00%