Employee Benefits (Details) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2013	Dec. 31, 2015 USD ($) Employee	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Employee Benefits
Collective bargaining arrangement, number of participating unionized employees | Employee		11,000
Collective bargaining arrangement, number of participating active employees and retirees | Employee		11,000
Collective bargaining agreements term	4 years
Qwest Communications International, Inc.
Employee Benefits
Description of related party transaction		In 2015, we agreed to a plan to settle the outstanding affiliate obligations, net balance with QCII over a 30 year term. Payments will be made on a monthly basis.
Repayments on affiliate obligation		$ 105
Allocated expenses by parent entities (as a percent)			92.00%	91.00%
CenturyLink, Inc.
Employee Benefits
Allocated expenses by parent entities (as a percent)		69.00%
Pension Plan
Employee Benefits
Net periodic benefit cost		$ 57	$ (98)	$ (178)
Pension Plan | CenturyLink, Inc.
Employee Benefits
Employer contributions to benefit plan		100
Unfunded status		(2,207)	(2,402)
Post-Retirement Benefit Plan
Employee Benefits
Net periodic benefit cost		17	128	$ 88
Post-Retirement Benefit Plan | CenturyLink, Inc.
Employee Benefits
Employer contributions to benefit plan		0
Unfunded status		$ (3,374)	$ (3,477)
Pension, Supplemental and Other Postretirement Benefit Plans | Qwest Communications International, Inc.
Employee Benefits
Description of related party transaction		In 2015, we agreed to a plan to settle the outstanding pension and post-retirement affiliate obligations, net balance with QCII over a 30 year term. Payments will be made on a monthly basis.
Repayments on affiliate obligation		$ 105
Change in accounting method accounted for as change in estimate | Pension, Supplemental and Other Postretirement Benefit Plans
Employee Benefits
Decrease in defined benefit plans net periodic benefit cost (financial effect)		The change in methodology resulted in a decrease of $7 million to our net periodic benefit cost for the year ended December 31, 2015
Net periodic benefit cost		$ (7)