Condensed Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES
Net income	$ 327.9us-gaap_ProfitLoss	$ 296.7us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by operating activities of continuing operations:
Discontinued operations, net	0.2	2.0
Depreciation expense	137.1us-gaap_CostOfServicesDepreciation	131.1us-gaap_CostOfServicesDepreciation
Gains (Losses) on Extinguishment of Debt	26.6	0
Share-based compensation expense	9.5us-gaap_ShareBasedCompensation	11.9us-gaap_ShareBasedCompensation
Deferred income tax (benefit) expense	15.0us-gaap_DeferredIncomeTaxExpenseBenefit	(5.7)us-gaap_DeferredIncomeTaxExpenseBenefit
Amortization of intangibles and other, net	(4.0)	(2.8)
Other	(6.8)us-gaap_OtherNoncashIncomeExpense	(0.1)us-gaap_OtherNoncashIncomeExpense
Changes in operating assets and liabilities	(37.8)	(0.2)
Net cash provided by operating activities of continuing operations	467.7	432.9
INVESTING ACTIVITIES
Additions to property and equipment	(397.1)	(272.6)
Proceeds from Sale of Short-term Investments	12.0	0
Other	0.4	0.8
Net cash provided by (used in) investing activities of continuing operations	(384.7)	(271.8)
FINANCING ACTIVITIES
Cash dividends paid	(35.2)us-gaap_PaymentsOfDividendsCommonStock	(175.7)us-gaap_PaymentsOfDividendsCommonStock
Payments of Debt Extinguishment Costs	(23.4)	0
Proceeds from Issuance of Senior Long-term Debt	1,078.7	0
Reduction of long-term borrowings	(861.7)us-gaap_RepaymentsOfLongTermDebt	(7.1)us-gaap_RepaymentsOfLongTermDebt
Payments of Financing Costs	(8.9)us-gaap_PaymentsOfFinancingCosts	0us-gaap_PaymentsOfFinancingCosts
Other	(1.3)	(6.2)
Net cash provided by (used in) financing activities	148.2	(189.0)
DISCONTINUED OPERATIONS
Operating activities	(8.7)	(16.3)
Investing activities	0.4	1.0
Net cash provided by discontinued operations	(8.3)	(15.3)
Effect of exchange rate changes on cash and cash equivalents	0.1	0.1
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	223.0	(43.1)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	664.8	165.6
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 887.8	$ 122.5

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.