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 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2013 |
USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | Equity Contract [Member] | Equity Contract [Member] | Equity Contract [Member] | Hedged Fixed-Rate Debt [Member] | Hedged Fixed-Rate Debt [Member] | Hedged Fixed-Rate Debt [Member] | Hedged Fixed-Rate Debt [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | Corporate Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | US Government Agencies Debt Securities [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Other Debt Obligations [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Collateralized Mortgage Backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Asset-backed Securities [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Securities, US [Member] | Equity Method and Other Investments [Member] | Equity Method and Other Investments [Member] | Equity Method and Other Investments [Member] | Equity Method and Other Investments [Member] | Buy US dollar Sell euro [Member] | Buy US dollar Sell euro [Member] | Buy euro Sell US dollar [Member] | Buy euro Sell US dollar [Member] | Buy US dollar Sell Japanese Yen [Member] | Buy US dollar Sell Japanese Yen [Member] |
| | | | | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | Equity Contract [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Foreign Exchange Contract [Member] | Foreign Exchange Contract [Member] | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | Equity Contract [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Foreign Exchange Contract [Member] | Foreign Exchange Contract [Member] | USD ($) | USD ($) | Equity Contract [Member] | Interest Rate Contract [Member] | Interest Rate Contract [Member] | Foreign Exchange Contract [Member] | Foreign Exchange Contract [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | Available-for-Sale Securities, Amortized Cost [Member] | Available-for-Sale Securities, Amortized Cost [Member] | USD ($) | EUR (€) | USD ($) | EUR (€) | USD ($) | JPY (¥) |
| | | | | | | | | | | | | | | | | | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | | | | | | | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | | | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | USD ($) | | | | | | |
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 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |