Name:	ctl_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeDeferredIncomeTaxBenefitExpense
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Represents the active health care benefit expenses.

No definition available.

Name:	ctl_DefinedBenefitPlanActiveHealthCareBenefitExpenses
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The amount of the deferred income tax benefit (expense) 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.

No definition available.

Name:	ctl_DefinedBenefitPlanAmortizationOfDeferredIncomeTaxExpenseBenefit
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Represents the difference between actual and expected returns on plan assets.

No definition available.

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The amounts in accumulated other comprehensive income related to deferred income tax benefit (expense) expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

No definition available.

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-- None. No documentation exists for this element. --

No definition available.

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Represents the contribution made by participating employees under the health care defined benefit plan.

No definition available.

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Represents the net change in accumulated other comprehensive income.

No definition available.

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Data Type:	xbrli:monetaryItemType
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-- None. No documentation exists for this element. --

No definition available.

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Represents the net change in deferred income tax (expense) benefit under accumulated other comprehensive income.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Represents the net change in gains (losses) under accumulated other comprehensive income.

No definition available.

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Data Type:	xbrli:monetaryItemType
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-- None. No documentation exists for this element. --

No definition available.

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Represents the net change in prior service benefit (cost) under accumulated other comprehensive income.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The amount of increases in plan assets attributable to purchases of investments.

No definition available.

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Th amount of decreases in plan assets attributable to the sale of investments.

No definition available.

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Tax impact of the change in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan, that has not been recognized in net periodic benefit cost. Also, may include the tax impact of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that occurred during the period and has not yet been recognized in net periodic benefit cost.

No definition available.

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The accumulated change in the value of either the projected benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption that has not been recognized in net periodic benefit cost, after tax. Plus, the cost (credit) resulting from a plan amendment, if applicable, that occurred during the period, after tax, and has not been recognized in net periodic benefit cost.

No definition available.

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Net of tax amount of the income statement impact of the reclassification adjustment for actuarial (gains) losses and prior service costs recognized as a component of net periodic benefit cost.

No definition available.

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The total fair value of the plan investments before other items to reconcile to fair value of plan assets.

No definition available.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds.

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The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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No definition available.

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Actual return on plan assets, separately identifying the amount related to assets sold during the period.

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Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

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The amount of gains or losses recognized in net periodic benefit cost.

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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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Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

No definition available.

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No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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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.

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

No definition available.

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Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

No definition available.

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No definition available.

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Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs.

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Amount before tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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No definition available.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

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