Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Federal
Current	$ 57,000,000	$ (49,000,000)	$ 384,000,000
Deferred	361,000,000	401,000,000	145,000,000
State
Current	15,000,000	25,000,000	67,000,000
Deferred	33,000,000	(6,000,000)	(13,000,000)
Foreign
Current	7,000,000	4,000,000
Total income tax expense	473,000,000	375,000,000	583,000,000
Income tax expense in the consolidated statements of income:
Attributable to income	473,000,000	375,000,000	583,000,000
Stockholders' equity:
Compensation expense for tax purposes in excess of amounts recognized for financial reporting purposes	(18,000,000)	(13,000,000)	(12,000,000)
Tax effect of the change in accumulated other comprehensive loss	(434,000,000)	(535,000,000)	(34,000,000)
Reconciliation of the statutory federal income tax rate to effective income tax rate
Statutory federal income tax rate (as a percent)	35.00%	35.00%	35.00%
State income taxes, net of federal income tax benefit (as a percent)	2.50%	1.30%	1.90%
Change in tax treatment of Medicare subsidy (as a percent)			0.30%
Nondeductible acquisition related costs (as a percent)		0.90%	0.20%
Nondeductible compensation pursuant to executive compensation limitations (as a percent)	0.50%	0.40%	0.20%
Reversal of valuation allowance on auction rate securities (as a percent)	(1.20%)
Foreign income taxes (as a percent)	0.30%	0.40%
Foreign valuation allowance (as a percent)		0.80%
Other, net (as a percent)	0.70%	0.80%	0.50%
Effective income tax rate (as a percent)	37.80%	39.60%	38.10%
Recognition of additional income tax expense due to non-deductible transaction cost related to recent acquisitions		24,000,000	4,000,000
Benefit on sale of auction rate securities, net of valuation allowance	12,000,000
Expense on reversal of valuation allowance on auction rate securities	6,000,000
Reversal of valuation allowance	16,000,000	16,000,000
Deferred tax assets
Postretirement and pension benefit costs	2,327,000,000	2,040,000,000
Net operating loss carryforwards	1,764,000,000	2,492,000,000
Other employee benefits	193,000,000	122,000,000
Other	754,000,000	802,000,000
Gross deferred tax assets	5,038,000,000	5,456,000,000
Less valuation allowance	(281,000,000)	(293,000,000)
Net deferred tax assets	4,757,000,000	5,163,000,000
Deferred tax liabilities
Property, plant and equipment, primarily due to depreciation differences	(3,983,000,000)	(3,638,000,000)
Goodwill and other intangible assets	(3,316,000,000)	(4,144,000,000)
Other	(211,000,000)	(162,000,000)
Gross deferred tax liabilities	(7,510,000,000)	(7,944,000,000)
Net deferred tax liability	(2,753,000,000)	(2,781,000,000)
Long-term deferred tax liability	3,644,000,000	3,800,000,000
Net current deferred tax asset	891,000,000	1,019,000,000
Deferred tax asset valuation allowance from future income of a special character		8,000,000
NOLs
Valuation allowance, primarily related to state NOLs	281,000,000
Assumed in Qwest and Savvis acquisitions		206,000,000
Increase in tax positions taken in the current year	3,000,000
Deferred tax asset valuation allowance adjustment	(12,000,000)
Summary of reconciliation of the change in gross unrecognized tax benefits activity
Unrecognized tax benefits, beginning of year	111,000,000	311,000,000
Assumed in Qwest and Savvis acquisitions		206,000,000
Increase in tax positions taken in the current year	3,000,000
Decrease due to the reversal of tax positions taken in a prior year	(34,000,000)	(13,000,000)
Decrease from the lapse of statute of limitations	(2,000,000)	(1,000,000)
Settlements		(392,000,000)
Unrecognized tax benefits, end of year	78,000,000	111,000,000	311,000,000
Unrecognized tax benefits that would impact effective tax rate	52,000,000	118,000,000
Accrued interest associated with unrecognized tax benefits	33,000,000	33,000,000
Amount of unrecognized tax benefit that may decrease within the next twelve months	32,000,000
State Jurisdiction
NOLs
Net operating losses	7,000,000,000
federal
NOLs
Net operating losses	$ 4,700,000,000