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Amount of long-term debt and capital lease obligations maturing after the fifth full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations maturing within the fifth full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations maturing within the first full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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Amount of long-term debt and capital lease obligations maturing within the fourth full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations maturing within the remainder of the fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations maturing within the second full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligations maturing within the third full fiscal year following the date of the most recent balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings and capital lease obligations as of the balance sheet date before deducting unamortized discount or premiums (if any).

+ References

No definition available.

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- Definition

Repayment of 0.25% of the original aggregate principal amount.

+ References

No definition available.

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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- Definition

The effective interest rate at the end of the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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Long-Term Debt - Textuals (Details) (USD $) In Millions, unless otherwise specified											3 Months Ended
	Jun. 30, 2013	Jun. 30, 2013 Tranche B 2016 Term Loan	Dec. 31, 2012 Tranche B 2016 Term Loan	Aug. 06, 2012 Tranche B 2016 Term Loan Level 3 Financing Inc.	Jun. 30, 2013 Tranche B 2019 Term Loan	Dec. 31, 2012 Tranche B 2019 Term Loan	Jun. 30, 2013 Tranche B-II 2019 Term Loan	Dec. 31, 2012 Tranche B-II 2019 Term Loan	Jun. 30, 2013 Convertible Senior Notes due 2013 (15.0%)	Dec. 31, 2012 Convertible Senior Notes due 2013 (15.0%)	Mar. 31, 2013 Convertible Senior Notes due 2013 (15.0%) Level 3 Communications, Inc.	Jan. 15, 2013 Convertible Senior Notes due 2013 (15.0%) Level 3 Communications, Inc.	Jun. 30, 2013 Senior Notes due 2019 (8.875%)	Dec. 31, 2012 Senior Notes due 2019 (8.875%)	Jun. 30, 2013 Senior Notes due 2019 (8.875%) Level 3 Communications, Inc.	Jun. 30, 2013 Senior Notes due 2020 (7.0%)	Dec. 31, 2012 Senior Notes due 2020 (7.0%)	Jun. 30, 2013 Senior Notes due 2020 (7.0%) Level 3 Financing Inc.
Long-term debt
Debt instrument, stated interest rate (as a percent)									15.00%	15.00%		15.00%	8.875%	8.875%	8.875%	7.00%	7.00%	7.00%
Extinguishment of Debt, Amount											$ 172
Debt instrument, effective interest rate at end of period (as a percent)		4.75%	4.75%		5.25%	5.25%	4.75%	4.75%
Tranche B 2016 Term Loan repayment of 0.25% of the original $600 million principal amount				0.25%
Future contractual maturities of long-term debt and capital leases (excluding discounts)
2013 (remaining six months)	18
2014	22
2015	788
2016	788
2017	5
2018	645
Thereafter	6,314
Total Debt Obligations	8,580
Debt Instrument, Face Amount		$ 596	$ 599	$ 600	$ 815	$ 815	$ 1,200	$ 1,200