Description of equity interests issued or issuable to acquire the entity.

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-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
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-Section S99
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Pending Acquisition of Level 3 (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Dec. 31, 2016
Business acquisition
Outstanding long-term debt		$ 19,976	$ 19,993
Level 3 Communications, Inc. \| Scenario, Forecast
Business acquisition
Price per share of stock in business acquisition (per share)	$ 26.50
Level 3 Communications, Inc. \| Common Stock \| Scenario, Forecast
Business acquisition
Stock issuable in business acquisition on a per share basis, Description	1.4286 of CenturyLink shares for each share of Level 3 common stock
CenturyLink, Inc. \| Level 3 Communications, Inc. \| Scenario, Forecast
Business acquisition
Business acquisition, ownership control (in percent)	51.00%
Level 3 Communications, Inc. \| Level 3 Communications, Inc.
Business acquisition
Outstanding long-term debt			$ 10,900
Level 3 Communications, Inc. \| Level 3 Communications, Inc. \| Scenario, Forecast
Business acquisition
Business acquisition, ownership control (in percent)	49.00%