Document and Entity Information Document - shares	3 Months Ended
	Mar. 31, 2018	May 04, 2018
Document and Entity Information
Entity Registrant Name	CENTURYLINK, INC
Entity Central Index Key	0000018926
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		1,078,846,346
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1