Severance and Leased Real Estate (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Severance
Restructuring reserve
Balance at the beginning of the period	$ 17	$ 17
Accrued to expense	87	31
Reversals and adjustments	(78)	(31)
Reversals and adjustments	0	0
Balance at the end of the period	26	17
Qwest Communications International Inc \| Leased real estate
Severance and Leased Real Estate
Current portion of leased real estate accrual	(14)
Noncurrent portion of leased real estate accrual	(82)
Weighted average lease terms (in years)	8 years 5 months 14 days
Restructuring reserve
Balance at the beginning of the period	113	131
Accrued to expense	1	0
Reversals and adjustments	(16)	(16)
Reversals and adjustments	2	(2)
Balance at the end of the period	$ 96	$ 113
Qwest Communications International Inc \| Leased real estate \| Minimum
Severance and Leased Real Estate
Remaining lease terms	4 months
Qwest Communications International Inc \| Leased real estate \| Maximum
Severance and Leased Real Estate
Remaining lease terms	11 years

Represents the remaining lease term.

No definition available.

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- Definition

Weighted average term of remaining leases assumed in connection with an acquisition.

+ References

No definition available.

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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- Definition

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

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