Condensed Consolidating Financial Information - Statement of Cash Flows (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	$ 199	$ 149
Cash Flows from Investing Activities:
Capital expenditures	(350)	(319)
(Increase) Decrease in restricted cash and securities, net	(63)	4
Proceeds from the sale of property, plant and equipment	4	1
Net Cash Used in Investing Activities	(409)	(314)
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	765.0	783.0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	(711)	(929)
Increase (decrease) due from affiliates, net	0	0
Net Cash Provided by (Used in) Financing Activities	54	(146)
Effect of Exchange Rates on Cash and Cash Equivalents	1	(7)
Net Change in Cash and Cash Equivalents	(155)	(318)
Cash and Cash Equivalents at Beginning of Period	616	836
Cash and Cash Equivalents at End of Period	461	518
Level 3 Communications, Inc.
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	(129)	(131)
Cash Flows from Investing Activities:
Capital expenditures	0	0
(Increase) Decrease in restricted cash and securities, net	0	0
Proceeds from the sale of property, plant and equipment	0	0
Net Cash Used in Investing Activities	0	0
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	292.0	170.0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	(245)	(328)
Increase (decrease) due from affiliates, net	(47)	224
Net Cash Provided by (Used in) Financing Activities	0	66
Effect of Exchange Rates on Cash and Cash Equivalents	0	0
Net Change in Cash and Cash Equivalents	(129)	(65)
Cash and Cash Equivalents at Beginning of Period	173	236
Cash and Cash Equivalents at End of Period	44	171
Level 3 Financing, Inc.
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	(279)	(277)
Cash Flows from Investing Activities:
Capital expenditures	0	0
(Increase) Decrease in restricted cash and securities, net	0	0
Proceeds from the sale of property, plant and equipment	0	0
Net Cash Used in Investing Activities	0	0
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	474.0	613.0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	(463)	(599)
Increase (decrease) due from affiliates, net	267	262
Net Cash Provided by (Used in) Financing Activities	278	276
Effect of Exchange Rates on Cash and Cash Equivalents	0	0
Net Change in Cash and Cash Equivalents	(1)	(1)
Cash and Cash Equivalents at Beginning of Period	7	8
Cash and Cash Equivalents at End of Period	6	7
Level 3 Communications, LLC
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	153	(28)
Cash Flows from Investing Activities:
Capital expenditures	(146)	(117)
(Increase) Decrease in restricted cash and securities, net	0	3
Proceeds from the sale of property, plant and equipment	1	0
Net Cash Used in Investing Activities	(145)	(114)
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	0	0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	0	(1)
Increase (decrease) due from affiliates, net	(29)	(19)
Net Cash Provided by (Used in) Financing Activities	(29)	(20)
Effect of Exchange Rates on Cash and Cash Equivalents	0	0
Net Change in Cash and Cash Equivalents	(21)	(162)
Cash and Cash Equivalents at Beginning of Period	350	431
Cash and Cash Equivalents at End of Period	329	269
Other Non-Guarantor Subsidiaries
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	454	585
Cash Flows from Investing Activities:
Capital expenditures	(204)	(202)
(Increase) Decrease in restricted cash and securities, net	(63)	1
Proceeds from the sale of property, plant and equipment	3	1
Net Cash Used in Investing Activities	(264)	(200)
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	(1.0)	0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	(3)	(1)
Increase (decrease) due from affiliates, net	(191)	(467)
Net Cash Provided by (Used in) Financing Activities	(195)	(468)
Effect of Exchange Rates on Cash and Cash Equivalents	1	(7)
Net Change in Cash and Cash Equivalents	(4)	(90)
Cash and Cash Equivalents at Beginning of Period	86	161
Cash and Cash Equivalents at End of Period	82	71
Eliminations
Condensed Consolidating Financial Information
Net Cash Provided by (Used in) Operating Activities	0	0
Cash Flows from Investing Activities:
Capital expenditures	0	0
(Increase) Decrease in restricted cash and securities, net	0	0
Proceeds from the sale of property, plant and equipment	0	0
Net Cash Used in Investing Activities	0	0
Cash Flows from Financing Activities:
Long-term debt borrowings, net of issuance costs	0	0
Payments on and repurchases of long-term debt, including current portions and refinancing costs	0	0
Increase (decrease) due from affiliates, net	0	0
Net Cash Provided by (Used in) Financing Activities	0	0
Effect of Exchange Rates on Cash and Cash Equivalents	0	0
Net Change in Cash and Cash Equivalents	0	0
Cash and Cash Equivalents at Beginning of Period	0	0
Cash and Cash Equivalents at End of Period	$ 0	$ 0

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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