Document and Entity Information Document - shares	6 Months Ended
	Jun. 30, 2015	Aug. 05, 2015
Entity Information [Line Items]
Entity Registrant Name	LEVEL 3 COMMUNICATIONS INC
Entity Central Index Key	0000794323
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		355,833,110
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2