Repayment of 0.25% of the original aggregate principal amount.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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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.

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

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-Name Regulation S-X (SX)

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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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Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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

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-Publisher SEC

-Name Regulation S-X (SX)

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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No definition available.

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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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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Amount of long-term debt and capital lease obligation maturing after the fifth fiscal year following the latest fiscal year.

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No definition available.

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Amount of long-term debt and capital lease obligation maturing in the fifth fiscal year following the latest fiscal year.

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No definition available.

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Amount of long-term debt and capital lease obligation maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt and capital lease obligation maturing in the third fiscal year following the latest fiscal year.

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No definition available.

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Amount of long-term debt and capital lease obligation maturing in the second fiscal year following the latest fiscal year.

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No definition available.

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Amount of long-term debt and capital lease obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

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No definition available.

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Amount of long-term debt and capital lease obligation maturing in the next fiscal year following the latest fiscal year.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Long-Term Debt - Textuals (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended				0 Months Ended				0 Months Ended				0 Months Ended					0 Months Ended				0 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2012 Tranche B 2016 Term Loan	Aug. 16, 2013 Tranche B 2016 Term Loan Level 3 Financing, Inc.	Aug. 16, 2013 Tranche B 2016 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR)	Aug. 16, 2013 Tranche B 2016 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR) Minimum	Sep. 30, 2013 Tranche B 2020 Term Loan	Aug. 16, 2013 Tranche B 2020 Term Loan Level 3 Financing, Inc.	Aug. 16, 2013 Tranche B 2020 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR)	Aug. 16, 2013 Tranche B 2020 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR) Minimum	Dec. 31, 2012 Tranche B 2019 Term Loan	Aug. 12, 2013 Tranche B 2019 Term Loan Level 3 Financing, Inc.	Aug. 12, 2013 Tranche B 2019 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR)	Aug. 12, 2013 Tranche B 2019 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR) Minimum	Sep. 30, 2013 Tranche B-III 2019 Term Loan	Aug. 12, 2013 Tranche B-III 2019 Term Loan Level 3 Financing, Inc.	Aug. 12, 2013 Tranche B-III 2019 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR)	Aug. 12, 2013 Tranche B-III 2019 Term Loan Level 3 Financing, Inc. London Interbank Offered Rate (LIBOR) Minimum	Sep. 30, 2013 15.0% Convertible Senior Notes due 2013	Dec. 31, 2012 15.0% Convertible Senior Notes due 2013	Jan. 15, 2013 15.0% Convertible Senior Notes due 2013 Level 3 Communications, Inc.	Sep. 30, 2013 8.875% Senior Notes due 2019	Dec. 31, 2012 8.875% Senior Notes due 2019	Sep. 30, 2013 8.875% Senior Notes due 2019 Level 3 Communications, Inc.	Sep. 30, 2013 7.0% Senior Notes due 2020	Dec. 31, 2012 7.0% Senior Notes due 2020	Sep. 30, 2013 7.0% Senior Notes due 2020 Level 3 Financing, Inc.
Long-term debt
Repayments of debt							$ 595.5								$ 815.0									$ 172.0
Aggregate principal amount							600.0				595.5								815.0
Debt Issuance Cost											7				10
Loss on modification and extinguishment of debt, net	(17)	(49)	(17)	(110)			(8)								(9)
Tranche B 2016 Term Loan repayment of 0.25% of the original $600 million principal amount							0.25%
Basis (LIBOR)								LIBOR				LIBOR				LIBOR				LIBOR
Basis Spread on Variable Rate								3.25%				3.00%				3.75%				3.00%
Stated interest rate (as a percent)						4.75%			1.50%	4.00%			1.00%	5.25%			1.50%	4.00%			1.00%	15.00%	15.00%	15.00%	8.875%	8.875%	8.875%	7.00%	7.00%	7.00%
Total Debt Obligations	8,598.0		8,598.0		8,780.0	599.0				595.5				815.0				815.0				0	172.0		300.0	300.0		775.0	775.0
2013 (remaining three months)	8		8
2014	28		28
2015	783		783
2016	208		208
2017	6		6
2018	646		646
Thereafter	$ 6,919		$ 6,919