Financial Instruments (Details)	3 Months Ended		9 Months Ended		12 Months Ended	3 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2012 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2013 Equity Contract [Member] USD ($)	Sep. 30, 2013 Equity Contract [Member] USD ($)	Sep. 30, 2012 Equity Contract [Member] USD ($)	Sep. 30, 2013 Hedged Fixed-Rate Debt [Member] USD ($)	Sep. 30, 2012 Hedged Fixed-Rate Debt [Member] USD ($)	Sep. 30, 2013 Hedged Fixed-Rate Debt [Member] USD ($)	Sep. 30, 2012 Hedged Fixed-Rate Debt [Member] USD ($)	Sep. 30, 2013 Interest Rate Contract [Member] USD ($)	Sep. 30, 2012 Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Interest Rate Contract [Member] USD ($)	Sep. 30, 2012 Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Carrying (Reported) Amount, Fair Value Disclosure [Member] Equity Contract [Member] USD ($)	Sep. 30, 2013 Carrying (Reported) Amount, Fair Value Disclosure [Member] Interest Rate Contract [Member] USD ($)	Dec. 31, 2012 Carrying (Reported) Amount, Fair Value Disclosure [Member] Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Carrying (Reported) Amount, Fair Value Disclosure [Member] Foreign Exchange Contract [Member] USD ($)	Dec. 31, 2012 Carrying (Reported) Amount, Fair Value Disclosure [Member] Foreign Exchange Contract [Member] USD ($)	Sep. 30, 2013 Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Fair Value, Inputs, Level 1 [Member] USD ($)	Dec. 31, 2012 Fair Value, Inputs, Level 1 [Member] USD ($)	Sep. 30, 2013 Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 Fair Value, Inputs, Level 2 [Member] Equity Contract [Member] USD ($)	Sep. 30, 2013 Fair Value, Inputs, Level 2 [Member] Interest Rate Contract [Member] USD ($)	Dec. 31, 2012 Fair Value, Inputs, Level 2 [Member] Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Fair Value, Inputs, Level 2 [Member] Foreign Exchange Contract [Member] USD ($)	Dec. 31, 2012 Fair Value, Inputs, Level 2 [Member] Foreign Exchange Contract [Member] USD ($)	Sep. 30, 2013 Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Estimate of Fair Value, Fair Value Disclosure [Member] Equity Contract [Member] USD ($)	Sep. 30, 2013 Estimate of Fair Value, Fair Value Disclosure [Member] Interest Rate Contract [Member] USD ($)	Dec. 31, 2012 Estimate of Fair Value, Fair Value Disclosure [Member] Interest Rate Contract [Member] USD ($)	Sep. 30, 2013 Estimate of Fair Value, Fair Value Disclosure [Member] Foreign Exchange Contract [Member] USD ($)	Dec. 31, 2012 Estimate of Fair Value, Fair Value Disclosure [Member] Foreign Exchange Contract [Member] USD ($)	Sep. 30, 2013 Corporate Debt Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Corporate Debt Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Corporate Debt Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Corporate Debt Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Corporate Debt Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 Corporate Debt Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 Corporate Debt Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Corporate Debt Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 US Government Agencies Debt Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 US Government Agencies Debt Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 US Government Agencies Debt Securities [Member] Fair Value, Inputs, Level 1 [Member] USD ($)	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Fair Value, Inputs, Level 1 [Member] USD ($)	Sep. 30, 2013 US Government Agencies Debt Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 US Government Agencies Debt Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 US Government Agencies Debt Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Other Debt Obligations [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Other Debt Obligations [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Other Debt Obligations [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Other Debt Obligations [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Other Debt Obligations [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 Other Debt Obligations [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 Other Debt Obligations [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Other Debt Obligations [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Collateralized Mortgage Backed Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Collateralized Mortgage Backed Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Collateralized Mortgage Backed Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Collateralized Mortgage Backed Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Collateralized Mortgage Backed Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 Collateralized Mortgage Backed Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 Collateralized Mortgage Backed Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Collateralized Mortgage Backed Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Asset-backed Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Asset-backed Securities [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Asset-backed Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Asset-backed Securities [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Asset-backed Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2012 Asset-backed Securities [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Sep. 30, 2013 Asset-backed Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Asset-backed Securities [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Equity Securities, US [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Equity Securities, US [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Equity Securities, US [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Equity Securities, US [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Equity Securities, US [Member] Fair Value, Inputs, Level 1 [Member] USD ($)	Dec. 31, 2012 Equity Securities, US [Member] Fair Value, Inputs, Level 1 [Member] USD ($)	Sep. 30, 2013 Equity Securities, US [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Equity Securities, US [Member] Estimate of Fair Value, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Equity Method and Other Investments [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Dec. 31, 2012 Equity Method and Other Investments [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member] USD ($)	Sep. 30, 2013 Equity Method and Other Investments [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Dec. 31, 2012 Equity Method and Other Investments [Member] Available-for-Sale Securities, Amortized Cost [Member] USD ($)	Sep. 30, 2013 Buy US dollar Sell euro [Member] USD ($)	Sep. 30, 2013 Buy US dollar Sell euro [Member] EUR (€)	Sep. 30, 2013 Buy euro Sell US dollar [Member] USD ($)	Sep. 30, 2013 Buy euro Sell US dollar [Member] EUR (€)	Sep. 30, 2013 Buy US dollar Sell Japanese Yen [Member] USD ($)	Sep. 30, 2013 Buy US dollar Sell Japanese Yen [Member] JPY (¥)
Available-for-sale Securities, Debt Securities	$ 7,600,500,000		$ 7,600,500,000
Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge									31,300,000	12,100,000	244,600,000	43,800,000
Cash and Cash Equivalents, Fair Value Disclosure																	4,368,900,000	4,018,800,000						4,368,900,000	4,018,800,000	4,315,200,000	3,964,400,000	53,700,000	54,400,000						4,368,900,000	4,018,800,000
Long-term Debt																	(5,282,900,000)	(5,531,300,000)										(5,570,200,000)	(5,996,600,000)						(5,570,200,000)	(5,996,600,000)
Derivative Assets, Current																				11,300,000		3,700,000	11,000,000								11,300,000		3,700,000	11,000,000				11,300,000		3,700,000	11,000,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Other, Percentage of Nonperforming Assets	90.00%
Maximum Remaining Maturity of Foreign Currency Derivatives	30 days
Description of Derivative Activity Volume Percent	60.00%		60.00%
Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments													(31,300,000)	(12,100,000)	(244,600,000)	(43,800,000)
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	8,800,000		8,800,000
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	2,300,000	2,300,000	6,700,000	6,700,000
Derivative Instruments, Gain (Loss) Recognized in Income, Net	33,900,000	(23,700,000)	26,400,000	(38,500,000)
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net						33,000,000	41,900,000	0
Derivative Assets, Noncurrent																				336,600,000	589,400,000										336,600,000	589,400,000						336,600,000	589,400,000
Derivative Liabilities, Current																			(37,500,000)	(4,300,000)		(15,400,000)	(17,500,000)							(37,500,000)	(4,300,000)		(15,400,000)	(17,500,000)			(37,500,000)			(15,400,000)	(17,500,000)
Derivative Liabilities, Noncurrent																			(4,400,000)											(4,400,000)							(4,400,000)
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	5,437,400,000		5,437,400,000
Available-for-sale Securities, Gross Unrealized Gains			259,600,000		140,500,000
Available-for-sale Securities, Gross Unrealized Losses			59,300,000		29,000,000
Available-for-sale Securities, Continuous Unrealized Gain Position, Fair Value	4,289,100,000		4,289,100,000		5,246,000,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	3,435,900,000		3,435,900,000		2,102,000,000
Other than Temporary Impairment Losses, Investments	0	800,000	5,200,000	8,200,000
Proceeds from Sale and Maturity of Available-for-sale Securities	2,785,500,000	1,698,800,000	10,230,600,000	5,334,100,000
Available-for-sale Securities, Gross Realized Gains	3,600,000	43,100,000	41,800,000	70,000,000
Available-for-sale Securities, Gross Realized Losses	4,200,000	2,200,000	12,100,000	7,400,000
Available-for-sale Securities, Current [Abstract]
Available-for-sale Securities, Debt Securities, Current																																										843,200,000	1,503,500,000	841,200,000	1,501,500,000	843,200,000	1,503,500,000	843,200,000	1,503,500,000	162,200,000	150,200,000	162,100,000	150,200,000	162,200,000	150,200,000			162,200,000	150,200,000	5,000,000	11,800,000	5,000,000	11,800,000	5,000,000	11,800,000	5,000,000	11,800,000
Available-for-sale Securities, Current, Total																	1,010,400,000	1,665,500,000						1,008,300,000	1,663,500,000
Available-for-sale Securities, Noncurrent [Abstract]
Available-for-sale Securities, Debt Securities, Noncurrent																																										4,508,100,000	3,351,300,000	4,513,400,000	3,322,900,000	4,508,100,000	3,351,300,000	4,508,100,000	3,351,300,000	1,131,900,000	1,362,700,000	1,138,600,000	1,360,300,000	1,045,600,000	1,122,400,000	86,300,000	240,300,000	1,131,900,000	1,362,700,000	7,400,000	3,300,000	8,200,000	3,300,000	7,400,000	3,300,000	7,400,000	3,300,000	588,100,000	668,100,000	603,500,000	677,700,000	588,100,000	668,100,000	588,100,000	668,100,000	359,000,000	519,000,000	363,600,000	523,500,000	359,000,000	519,000,000	359,000,000	519,000,000
Available-for-sale Securities, Equity Securities, Noncurrent																																																																																				370,800,000	175,800,000	139,800,000	83,000,000	370,800,000	175,800,000	370,800,000	175,800,000
Other Long-term Investments																																																																																												254,900,000	233,100,000	254,900,000	233,100,000
Available-for-sale Securities, Noncurrent, Total																	7,220,200,000	6,313,300,000						7,022,000,000	6,203,800,000
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	1,010,400,000		1,010,400,000
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	451,000,000		451,000,000
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	701,700,000		701,700,000
Derivative Liability, Notional Amount																																																																																																872,300,000			287,300,000	362,300,000
Derivative Asset, Notional Amount																																																																																																	651,700,000	388,600,000			35,830,000,000
Derivative, Notional Amount	400,000,000		400,000,000
Maximum Length of Time Hedged in Interest Rate Cash Flow Hedge	30 years
Short-term Debt	$ 1,000,000,000		$ 1,000,000,000