Represents the aggregate amount of net amortization and deferral recognized in net periodic benefit cost.

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For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The increase in the fair value of plan assets from contributions made by the employer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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Employee Benefits (Details) (USD $) In Millions	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended
Employee Benefits (Details) (USD $) In Millions	Jun. 30, 2011 Pension plans	Jun. 30, 2010 Pension plans	Jun. 30, 2011 Pension plans	Jun. 30, 2010 Pension plans	Jun. 30, 2011 Pension plans Qwest sponsored defined benefit plans	Jun. 30, 2011 Pension plans Qwest sponsored defined benefit plans	Apr. 02, 2011 Pension plans Qwest sponsored defined benefit plans	Jun. 30, 2011 Postretirement benefit plans	Jun. 30, 2010 Postretirement benefit plans	Jun. 30, 2011 Postretirement benefit plans	Jun. 30, 2010 Postretirement benefit plans	Jun. 30, 2011 Postretirement benefit plans Qwest sponsored defined benefit plans	Jun. 30, 2011 Postretirement benefit plans Qwest sponsored defined benefit plans	Apr. 02, 2011 Postretirement benefit plans Qwest sponsored defined benefit plans
Employee benefits.
Liability for the unfunded status of the defined benefit plans							$ 479							$ 2,516
Estimated accumulated benefit obligations														3,284
Estimated fair value of plan assets							7,788							768
Service cost	20	17	28	33				4	3	7	7
Interest cost	169	58	229	122				48	8	55	16
Expected return on plan assets	(212)	(71)	(285)	(142)				(13)	(1)	(14)	(2)
Net amortization and deferral	3	3	7	10
Amortization of unrecognized prior service cost								(1)		(1)	(1)
Net periodic pension (benefit) expense	(20)	7	(21)	23	(18)	(18)		38	10	47	20	30	30
Contributions to defined benefit plans			100
Estimated projected benefit obligations							$ 8,267