Available-For-Sale Securities (Tables)
| 9 Months Ended |
|---|
Sep. 30, 2011 |
|---|
| Available-For-Sale Securities [Abstract] | |
| Summary Of Available-For-Sale Debt And Equity Securities At Estimated Fair Value |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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| |
|
Amortized
Cost |
|
|
Gross
Unrealized
Gains |
|
|
Gross
Unrealized
Losses |
|
|
Estimated
Fair Value |
|
|
September 30, 2011 |
|
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|
|
|
|
|
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|
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|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
1,147,146 |
|
|
$ |
8,505 |
|
|
$ |
(322 |
) |
|
$ |
1,155,329 |
|
|
Money market funds |
|
|
372,260 |
|
|
|
— |
|
|
|
— |
|
|
|
372,260 |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
1,082,230 |
|
|
|
8,593 |
|
|
|
(236 |
) |
|
|
1,090,587 |
|
|
Municipal debt securities |
|
|
24,410 |
|
|
|
183 |
|
|
|
(2 |
) |
|
|
24,591 |
|
|
Non-U.S. government securities |
|
|
266,234 |
|
|
|
1,450 |
|
|
|
(30,606 |
) |
|
|
237,078 |
|
|
Corporate debt securities |
|
|
1,698,857 |
|
|
|
9,242 |
|
|
|
(4,231 |
) |
|
|
1,703,868 |
|
|
Residential mortgage and asset-backed securities |
|
|
317,371 |
|
|
|
1,063 |
|
|
|
(1,908 |
) |
|
|
316,526 |
|
|
Student loan-backed securities |
|
|
61,300 |
|
|
|
— |
|
|
|
(4,793 |
) |
|
|
56,507 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total debt securities |
|
|
4,969,808 |
|
|
|
29,036 |
|
|
|
(42,098 |
) |
|
|
4,956,746 |
|
|
Equity securities |
|
|
1,451 |
|
|
|
3,816 |
|
|
|
— |
|
|
|
5,267 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
4,971,259 |
|
|
$ |
32,852 |
|
|
$ |
(42,098 |
) |
|
$ |
4,962,013 |
|
| |
|
|
|
|
|
|
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|
|
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|
| |
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|
|
December 31, 2010 |
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|
|
|
|
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|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
1,349,348 |
|
|
$ |
7,109 |
|
|
$ |
(1,020 |
) |
|
$ |
1,355,437 |
|
|
Money market funds |
|
|
520,063 |
|
|
|
— |
|
|
|
— |
|
|
|
520,063 |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
1,284,654 |
|
|
|
11,919 |
|
|
|
(463 |
) |
|
|
1,296,110 |
|
|
Municipal debt securities |
|
|
17,543 |
|
|
|
103 |
|
|
|
(21 |
) |
|
|
17,625 |
|
|
Non-U.S. government securities |
|
|
286,410 |
|
|
|
1,880 |
|
|
|
(86 |
) |
|
|
288,204 |
|
|
Corporate debt securities |
|
|
1,112,976 |
|
|
|
8,040 |
|
|
|
(1,762 |
) |
|
|
1,119,254 |
|
|
Residential mortgage and asset-backed securities |
|
|
277,359 |
|
|
|
923 |
|
|
|
(1,239 |
) |
|
|
277,043 |
|
|
Student loan-backed securities |
|
|
75,900 |
|
|
|
— |
|
|
|
(5,129 |
) |
|
|
70,771 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total debt securities |
|
|
4,924,253 |
|
|
|
29,974 |
|
|
|
(9,720 |
) |
|
|
4,944,507 |
|
|
Equity securities |
|
|
1,451 |
|
|
|
3,180 |
|
|
|
— |
|
|
|
4,631 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
4,925,704 |
|
|
$ |
33,154 |
|
|
$ |
(9,720 |
) |
|
$ |
4,949,138 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
| Summary Of The Classification Of Available-For-Sale Debt And Equity Securities |
| |
|
|
|
|
|
|
|
|
| |
|
September 30,
2011 |
|
|
December 31,
2010 |
|
|
Cash and cash equivalents |
|
$ |
389,256 |
|
|
$ |
538,946 |
|
|
Short-term marketable securities |
|
|
1,347,776 |
|
|
|
1,190,789 |
|
|
Long-term marketable securities |
|
|
3,224,981 |
|
|
|
3,219,403 |
|
| |
|
|
|
|
|
|
|
|
|
Total |
|
$ |
4,962,013 |
|
|
$ |
4,949,138 |
|
| |
|
|
|
|
|
|
|
| |
| Summary Of Available-For-Sale Debt Securities By Contractual Maturity |
| |
|
|
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|
|
|
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|
| |
|
September 30, 2011 |
|
|
December 31, 2010 |
|
| |
|
Amortized Cost |
|
|
Fair Value |
|
|
Amortized Cost |
|
|
Fair Value |
|
|
Less than one year |
|
$ |
1,732,877 |
|
|
$ |
1,737,032 |
|
|
$ |
1,726,095 |
|
|
$ |
1,729,735 |
|
|
Greater than one year but less than five years |
|
|
3,103,055 |
|
|
|
3,090,532 |
|
|
|
3,022,744 |
|
|
|
3,044,114 |
|
|
Greater than five years but less than ten years |
|
|
32,160 |
|
|
|
32,703 |
|
|
|
33,076 |
|
|
|
33,580 |
|
|
Greater than ten years |
|
|
101,716 |
|
|
|
96,479 |
|
|
|
142,338 |
|
|
|
137,078 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
4,969,808 |
|
|
$ |
4,956,746 |
|
|
$ |
4,924,253 |
|
|
$ |
4,944,507 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
| Summary Of Gross Realized Gains And Losses Related To Sales Of Marketable Securities |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Three Months Ended
September 30, |
|
|
Nine Months Ended
September 30, |
|
| |
|
2011 |
|
|
2010 |
|
|
2011 |
|
|
2010 |
|
|
Gross realized gains on sales |
|
$ |
4,830 |
|
|
$ |
1,290 |
|
|
$ |
13,784 |
|
|
$ |
10,588 |
|
|
Gross realized losses on sales |
|
$ |
(644 |
) |
|
$ |
(260 |
) |
|
$ |
(2,421 |
) |
|
$ |
(2,434 |
) | |
| Summary Of Available-For-Sale Debt Securities In A Continuous Unrealized Loss Position Deemed Not To Be Other-Than-Temporarily Impaired |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Less Than 12 Months |
|
|
12 Months or Greater |
|
|
Total |
|
| |
|
Gross
Unrealized
Losses |
|
|
Estimated
Fair Value |
|
|
Gross
Unrealized
Losses |
|
|
Estimated
Fair Value |
|
|
Gross
Unrealized
Losses |
|
|
Estimated
Fair Value |
|
|
September 30, 2011 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
(322 |
) |
|
$ |
249,055 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
(322 |
) |
|
$ |
249,055 |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
(236 |
) |
|
|
179,879 |
|
|
|
— |
|
|
|
— |
|
|
|
(236 |
) |
|
|
179,879 |
|
|
Municipal debt securities |
|
|
(2 |
) |
|
|
9,785 |
|
|
|
— |
|
|
|
— |
|
|
|
(2 |
) |
|
|
9,785 |
|
|
Non-U.S. government securities |
|
|
(30,604 |
) |
|
|
25,314 |
|
|
|
(2 |
) |
|
|
2,995 |
|
|
|
(30,606 |
) |
|
|
28,309 |
|
|
Corporate debt securities |
|
|
(4,182 |
) |
|
|
548,008 |
|
|
|
(49 |
) |
|
|
6,298 |
|
|
|
(4,231 |
) |
|
|
554,306 |
|
|
Residential mortgage and asset-backed securities |
|
|
(739 |
) |
|
|
100,102 |
|
|
|
(1,169 |
) |
|
|
60,755 |
|
|
|
(1,908 |
) |
|
|
160,857 |
|
|
Student loan-backed securities |
|
|
— |
|
|
|
— |
|
|
|
(4,793 |
) |
|
|
56,507 |
|
|
|
(4,793 |
) |
|
|
56,507 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
(36,085 |
) |
|
$ |
1,112,143 |
|
|
$ |
(6,013 |
) |
|
$ |
126,555 |
|
|
$ |
(42,098 |
) |
|
$ |
1,238,698 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
December 31, 2010 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
(1,020 |
) |
|
$ |
531,184 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
(1,020 |
) |
|
$ |
531,184 |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
(463 |
) |
|
|
226,176 |
|
|
|
— |
|
|
|
— |
|
|
|
(463 |
) |
|
|
226,176 |
|
|
Municipal debt securities |
|
|
(21 |
) |
|
|
4,688 |
|
|
|
— |
|
|
|
— |
|
|
|
(21 |
) |
|
|
4,688 |
|
|
Non-U.S. government securities |
|
|
(86 |
) |
|
|
44,317 |
|
|
|
— |
|
|
|
— |
|
|
|
(86 |
) |
|
|
44,317 |
|
|
Corporate debt securities |
|
|
(1,762 |
) |
|
|
459,412 |
|
|
|
— |
|
|
|
— |
|
|
|
(1,762 |
) |
|
|
459,412 |
|
|
Residential mortgage and asset-backed securities |
|
|
(1,239 |
) |
|
|
197,330 |
|
|
|
— |
|
|
|
— |
|
|
|
(1,239 |
) |
|
|
197,330 |
|
|
Student loan-backed securities |
|
|
— |
|
|
|
— |
|
|
|
(5,129 |
) |
|
|
70,771 |
|
|
|
(5,129 |
) |
|
|
70,771 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
(4,591 |
) |
|
$ |
1,463,107 |
|
|
$ |
(5,129 |
) |
|
$ |
70,771 |
|
|
$ |
(9,720 |
) |
|
$ |
1,533,878 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |