Debt (Carrying Value Of Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 14,752.2us-gaap_LongTermDebt	$ 14,091.6us-gaap_LongTermDebt
Current portion of long-term debt	(625.0)us-gaap_LongTermDebtCurrent	(518.0)us-gaap_LongTermDebtCurrent
Long-term debt, less current portion	14,127.2us-gaap_LongTermDebtNoncurrent	13,573.6us-gaap_LongTermDebtNoncurrent
Senior Unsecured Notes [Member] \| 5.000%, due 2014 [Member]
Debt Instrument [Line Items]
Long-term debt	0	518.0
Interest rate on long-term debt	5.00%	5.00%
Senior Unsecured Notes [Member] \| 1.250%, due 2015 [Member]
Debt Instrument [Line Items]
Long-term debt	625.0	624.9
Interest rate on long-term debt	1.25%	1.25%
Senior Unsecured Notes [Member] \| 5.250%, due 2016 [Member]
Debt Instrument [Line Items]
Long-term debt	0	1,109.6
Interest rate on long-term debt	5.25%	5.25%
Senior Unsecured Notes [Member] \| 2.375%, due 2017 [Member]
Debt Instrument [Line Items]
Long-term debt	400.1	399.6
Interest rate on long-term debt	2.375%	2.375%
Senior Unsecured Notes [Member] \| 5.875%, due 2017 [Member]
Debt Instrument [Line Items]
Long-term debt	527.7	545.1
Interest rate on long-term debt	5.875%	5.875%
Senior Unsecured Notes [Member] \| 1.875%, due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt	619.0	614.5
Interest rate on long-term debt	1.875%	1.875%
Senior Unsecured Notes [Member] \| 2.300%, due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt	648.0	647.5
Interest rate on long-term debt	2.30%	2.30%
Senior Unsecured Notes [Member] \| 2.250%, due 2019 [Member]
Debt Instrument [Line Items]
Long-term debt	848.2	0
Interest rate on long-term debt	2.25%	2.25%
Senior Unsecured Notes [Member] \| 7.000%, due 2019 [Member]
Debt Instrument [Line Items]
Long-term debt	440.0	452.9
Interest rate on long-term debt	7.00%	7.00%
Senior Unsecured Notes [Member] \| 4.350%, due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	698.6	688.9
Interest rate on long-term debt	4.35%	4.35%
Senior Unsecured Notes [Member] \| 3.700%, due 2021 [Member]
Debt Instrument [Line Items]
Long-term debt	699.4	699.4
Interest rate on long-term debt	3.70%	3.70%
Senior Unsecured Notes [Member] \| 3.125%, due 2022 [Member]
Debt Instrument [Line Items]
Long-term debt	846.7	846.3
Interest rate on long-term debt	3.125%	3.125%
Senior Unsecured Notes [Member] \| 3.300%, due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt	997.2	996.9
Interest rate on long-term debt	3.30%	3.30%
Senior Unsecured Notes [Member] \| 3.500%, due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt	796.1	0
Interest rate on long-term debt	3.50%	3.50%
Senior Unsecured Notes [Member] \| 5.950%, due 2034 [Member]
Debt Instrument [Line Items]
Long-term debt	447.3	447.3
Interest rate on long-term debt	5.95%	5.95%
Senior Unsecured Notes [Member] \| 5.850%, due 2036 [Member]
Debt Instrument [Line Items]
Long-term debt	772.0	775.6
Interest rate on long-term debt	5.85%	5.85%
Senior Unsecured Notes [Member] \| 6.375%, due 2037 [Member]
Debt Instrument [Line Items]
Long-term debt	644.1	651.4
Interest rate on long-term debt	6.375%	6.375%
Senior Unsecured Notes [Member] \| 5.800%, due 2040 [Member]
Debt Instrument [Line Items]
Long-term debt	208.3	216.2
Interest rate on long-term debt	5.80%	5.80%
Senior Unsecured Notes [Member] \| 4.625%, due 2042 [Member]
Debt Instrument [Line Items]
Long-term debt	893.9	893.9
Interest rate on long-term debt	4.625%	4.625%
Senior Unsecured Notes [Member] \| 4.650%, due 2043 [Member]
Debt Instrument [Line Items]
Long-term debt	994.4	994.4
Interest rate on long-term debt	4.65%	4.65%
Senior Unsecured Notes [Member] \| 4.650%, due 2044 [Member]
Debt Instrument [Line Items]
Long-term debt	798.3	0
Interest rate on long-term debt	4.65%	4.65%
Senior Unsecured Notes [Member] \| 5.100%, due 2044 [Member]
Debt Instrument [Line Items]
Long-term debt	599.2	599.1
Interest rate on long-term debt	5.10%	5.10%
Senior Unsecured Notes [Member] \| 4.850%, due 2054 [Member]
Debt Instrument [Line Items]
Long-term debt	249.4	0
Interest rate on long-term debt	4.85%	4.85%
Convertible Debt [Member] \| 2.750%, due 2042 [Member]
Debt Instrument [Line Items]
Long-term debt	974.4	966.0
Interest rate on long-term debt	2.75%	2.75%
Surplus Notes [Member] \| 9.000%, due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt	24.9	24.9
Interest rate on long-term debt	9.00%	9.00%
Commercial Paper [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 379.2

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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