Investment Securities (Details 5) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair value of marketable securities
Total	$ 1,019,820	$ 1,150,815
Corporate Bonds
Fair value of marketable securities
Debt security	922,343	1,049,139
Other
Fair value of marketable securities
Debt security	42,048	59,971
Strategic equity securities
Fair value of marketable securities
Equity security	55,429	41,705
Level 3
Fair value of marketable securities
Fair value of investments	0	0
Fair value measurements on recurring basis \| Total
Fair value of marketable securities
Cash equivalents (including restricted)	412,467	437,886
Total	1,019,820	1,150,815
Fair value measurements on recurring basis \| Total \| Corporate Bonds
Fair value of marketable securities
Debt security	922,343	1,049,139
Fair value measurements on recurring basis \| Total \| Other
Fair value of marketable securities
Debt security	42,048	59,971
Fair value measurements on recurring basis \| Total \| Strategic equity securities
Fair value of marketable securities
Equity security	55,429	41,705
Fair value measurements on recurring basis \| Level 1
Fair value of marketable securities
Cash equivalents (including restricted)	9,126	58,108
Total	61,147	47,335
Fair value measurements on recurring basis \| Level 1 \| Other
Fair value of marketable securities
Debt security	5,718	5,630
Fair value measurements on recurring basis \| Level 1 \| Strategic equity securities
Fair value of marketable securities
Equity security	55,429	41,705
Fair value measurements on recurring basis \| Level 2
Fair value of marketable securities
Cash equivalents (including restricted)	403,341	379,778
Total	958,673	1,103,480
Fair value measurements on recurring basis \| Level 2 \| Corporate Bonds
Fair value of marketable securities
Debt security	922,343	1,049,139
Fair value measurements on recurring basis \| Level 2 \| Other
Fair value of marketable securities
Debt security	$ 36,330	$ 54,341

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

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-SubTopic 10

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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