v2.4.0.6

Financial Instruments (Tables) | 9 Months Ended
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Sep. 30, 2012
Investments, All Other Investments [Abstract] |
Marketable Debt and Equity Securities |
As of September 30, 2012 (In millions) | Fair Value |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Amortized Cost
Available-for-sale: |  |  |  |  |  |  |
Corporate debt securities |  |  |  |  |  |  |
Current | $ | 302.8 |  |  | $ | 0.4 |  |  | $ | (0.1 | ) |  | $ | 302.5 |
Non-current | 611.9 |  |  | 3.3 |  |  | (0.2 | ) |  | 608.8 |
Government securities |  |  |  |  |  |  |
Current | 845.6 |  |  | 0.4 |  |  | — |  |  | 845.2 |
Non-current | 694.3 |  |  | 0.9 |  |  | — |  |  | 693.4 |
Mortgage and other asset backed securities |  |  |  |  |  |  |
Current | 5.7 |  |  | — |  |  | — |  |  | 5.7 |
Non-current | 435.3 |  |  | 1.6 |  |  | (1.1 | ) |  | 434.8 |
Total marketable debt securities | $ | 2,895.6 |  |  | $ | 6.6 |  |  | $ | (1.4 | ) |  | $ | 2,890.4 |
Marketable equity securities, non-current | $ | 1.2 |  |  | $ | — |  |  | $ | — |  |  | $ | 1.2 |
As of December 31, 2011 (In millions) | Fair Value |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Amortized Cost
Available-for-sale: |  |  |  |  |  |  |
Corporate debt securities |  |  |  |  |  |  |
Current | $ | 155.0 |  |  | $ | 0.2 |  |  | $ | (0.1 | ) |  | $ | 154.9 |
Non-current | 447.6 |  |  | 1.2 |  |  | (1.5 | ) |  | 447.9 |
Government securities |  |  |  |  |  |  |
Current | 1,021.0 |  |  | 0.4 |  |  | — |  |  | 1,020.6 |
Non-current | 695.5 |  |  | 0.9 |  |  | (0.2 | ) |  | 694.8 |
Mortgage and other asset backed securities |  |  |  |  |  |  |
Current | 0.1 |  |  | — |  |  | — |  |  | 0.1 |
Non-current | 273.7 |  |  | 0.5 |  |  | (1.3 | ) |  | 274.5 |
Total marketable debt securities | $ | 2,592.9 |  |  | $ | 3.2 |  |  | $ | (3.1 | ) |  | $ | 2,592.8 |
Marketable equity securities, non-current | $ | 0.1 |  |  | $ | — |  |  | $ | (0.1 | ) |  | $ | 0.2 |
Summary of financial assets with original maturities of less than 90 days included within cash and cash equivalents |
(In millions) | As of September 30, 2012 |  | As of December 31, 2011
Commercial paper | $ | 16.3 |  |  | $ | — |
Repurchase agreements | 108.7 |  |  | 8.8 |
Short-term debt securities | 184.0 |  |  | 391.0 |
Total | $ | 309.0 |  |  | $ | 399.8 |
Summary of Contractual Maturities: Available-for-Sale Securities |
| As of September 30, 2012 |  | As of December 31, 2011
(In millions) | Estimated Fair Value |  | Amortized Cost |  | Estimated Fair Value |  | Amortized Cost
Due in one year or less | $ | 1,154.0 |  |  | $ | 1,153.4 |  |  | $ | 1,176.1 |  |  | $ | 1,175.6 |
Due after one year through five years | 1,529.8 |  |  | 1,525.5 |  |  | 1,251.6 |  |  | 1,251.4 |
Due after five years | 211.8 |  |  | 211.5 |  |  | 165.2 |  |  | 165.8 |
Total available-for-sale securities | $ | 2,895.6 |  |  | $ | 2,890.4 |  |  | $ | 2,592.9 |  |  | $ | 2,592.8 |
Proceeds from Marketable Debt Securities |
| For the Three Months Ended September 30, |  | For the Nine Months Ended September 30,
(In millions) | 2012 |  | 2011 |  | 2012 |  | 2011
Proceeds from maturities and sales | $ | 491.3 |  |  | $ | 306.2 |  |  | $ | 1,913.4 |  |  | $ | 1,476.1 |
Realized gains | $ | 0.4 |  |  | $ | 0.3 |  |  | $ | 1.7 |  |  | $ | 3.4 |
Realized losses | $ | (0.8 | ) |  | $ | (0.4 | ) |  | $ | (2.7 | ) |  | $ | (1.7 | )

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