|
Available-For-Sale Securities (Tables)
|
12 Months Ended |
|
Dec. 31, 2011
|
| Available-For-Sale Securities [Abstract] |
|
| Summary Of Available-For-Sale Debt And Equity Securities At Estimated Fair Value |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Amortized
Cost |
|
|
Gross
Unrealized
Gains |
|
|
Gross
Unrealized
Losses |
|
|
Estimated
Fair Value |
|
|
December 31, 2011 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
Money market funds |
|
|
7,455,982 |
|
|
|
— |
|
|
|
— |
|
|
|
7,455,982 |
|
|
Certificates of deposit |
|
|
1,140,000 |
|
|
|
— |
|
|
|
(18 |
) |
|
|
1,139,982 |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Municipal debt securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Non-U.S. government securities |
|
|
55,246 |
|
|
|
— |
|
|
|
(30,505 |
) |
|
|
24,741 |
|
|
Corporate debt securities |
|
|
404,994 |
|
|
|
— |
|
|
|
(5 |
) |
|
|
404,989 |
|
|
Residential mortgage and asset-backed securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Student loan-backed securities |
|
|
51,500 |
|
|
|
— |
|
|
|
(4,548 |
) |
|
|
46,952 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total debt securities |
|
|
9,107,722 |
|
|
|
— |
|
|
|
(35,076 |
) |
|
|
9,072,646 |
|
|
Equity securities |
|
|
1,451 |
|
|
|
7,052 |
|
|
|
— |
|
|
|
8,503 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
9,109,173 |
|
|
$ |
7,052 |
|
|
$ |
(35,076 |
) |
|
$ |
9,081,149 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2010 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
1,349,348 |
|
|
$ |
7,109 |
|
|
$ |
(1,020 |
) |
|
$ |
1,355,437 |
|
|
Money market funds |
|
|
520,063 |
|
|
|
— |
|
|
|
— |
|
|
|
520,063 |
|
|
Certificates of deposit |
|
|
127,594 |
|
|
|
41 |
|
|
|
(16 |
) |
|
|
127,619 |
|
|
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 |
|
|
985,382 |
|
|
|
7,999 |
|
|
|
(1,746 |
) |
|
|
991,635 |
|
|
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 |
| |
|
|
|
|
|
|
|
|
| |
|
December 31, 2011 |
|
|
December 31, 2010 |
|
|
Cash and cash equivalents |
|
$ |
9,000,954 |
|
|
$ |
538,946 |
|
|
Short-term marketable securities |
|
|
16,491 |
|
|
|
1,190,789 |
|
|
Long-term marketable securities |
|
|
63,704 |
|
|
|
3,219,403 |
|
| |
|
|
|
|
|
|
|
|
|
Total |
|
$ |
9,081,149 |
|
|
$ |
4,949,138 |
|
| |
|
|
|
|
|
|
|
| |
| Summary Of Available-For-Sale Debt Securities By Contractual Maturity |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
December 31, 2011 |
|
|
December 31, 2010 |
|
| |
|
Amortized Cost |
|
|
Fair Value |
|
|
Amortized Cost |
|
|
Fair Value |
|
|
Less than one year |
|
$ |
1,574,140 |
|
|
$ |
1,561,462 |
|
|
$ |
1,726,095 |
|
|
$ |
1,729,735 |
|
|
Greater than one year but less than five years |
|
|
26,100 |
|
|
|
8,249 |
|
|
|
3,022,744 |
|
|
|
3,044,114 |
|
|
Greater than five years but less than ten years |
|
|
— |
|
|
|
— |
|
|
|
33,076 |
|
|
|
33,580 |
|
|
Greater than ten years |
|
|
7,507,482 |
|
|
|
7,502,935 |
|
|
|
142,338 |
|
|
|
137,078 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
9,107,722 |
|
|
$ |
9,072,646 |
|
|
$ |
4,924,253 |
|
|
$ |
4,944,507 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
| Summary Of Gross Realized Gains And Losses Related To Sales Of Marketable Securities |
| |
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
Year Ended December 31, |
|
| |
|
2011 |
|
|
2010 |
|
|
2009 |
|
|
Gross realized gains on sales |
|
$ |
42,849 |
|
|
$ |
13,254 |
|
|
$ |
10,373 |
|
|
Gross realized losses on sales |
|
$ |
(12,526 |
) |
|
$ |
(3,657 |
) |
|
$ |
(1,405 |
) | |
| 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 |
|
|
December 31, 2011 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
— |
|
|
U.S. government agencies and FDIC guaranteed securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Municipal debt securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Non-U.S. government securities |
|
|
(30,505 |
) |
|
|
24,741 |
|
|
|
— |
|
|
|
— |
|
|
|
(30,505 |
) |
|
|
24,741 |
|
|
Corporate debt securities |
|
|
(5 |
) |
|
|
224,989 |
|
|
|
— |
|
|
|
— |
|
|
|
(5 |
) |
|
|
224,989 |
|
|
Certificates of deposit |
|
|
(18 |
) |
|
|
1,019,982 |
|
|
|
— |
|
|
|
— |
|
|
|
(18 |
) |
|
|
1,019,982 |
|
|
Residential mortgage and asset-backed securities |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
Student loan-backed securities |
|
|
— |
|
|
|
— |
|
|
|
(4,548 |
) |
|
|
46,952 |
|
|
|
(4,548 |
) |
|
|
46,952 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
(30,528 |
) |
|
$ |
1,269,712 |
|
|
$ |
(4,548 |
) |
|
$ |
46,952 |
|
|
$ |
(35,076 |
) |
|
$ |
1,316,664 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2010 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Debt securities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury securities |
|
$ |
(1,020 |
) |
|
$ |
531,184 |
|
|
$ |
— |
|
|
$ |
— |
|
|
$ |
(1,020 |
) |
|
$ |
531,184 |
|
|
Certificates of deposit |
|
|
(13 |
) |
|
|
39,987 |
|
|
|
— |
|
|
|
— |
|
|
|
(13 |
) |
|
|
39,987 |
|
|
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 |
|
|
(1,749 |
) |
|
|
419,425 |
|
|
|
— |
|
|
|
— |
|
|
|
(1,749 |
) |
|
|
419,425 |
|
|
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 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |