Investments and Fair Value Disclosures (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Assets
Cash equivalents and certificates of deposit carrying value	$ 54,165	$ 71,147
Short and long-term investments, Carrying Value	109,973	97,749
Total assets, Carrying Value	164,138	168,896
Cash equivalents and certificates of deposit, Fair Value	54,165	71,147
Short and long-term investments, Fair Value	109,973	97,749
Total cash equivalents, certificates of deposit and investments	164,138	168,896
Liabilities
Liabilities, Carrying Value	120,923
Total liabilities, Carrying Value	84,971	83,089
Total liabilities, Fair Value	120,923	121,352
Convertible senior notes [Member]
Liabilities
Liabilities, Carrying Value	84,048	81,737
Liabilities, Fair Value	120,000	120,000
Notes payable and bank loans [Member]
Liabilities
Liabilities, Carrying Value	923	1,352
Liabilities, Fair Value	$ 923	$ 1,352

Cash equivalents and certificates of deposit carrying value.

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- Definition

Financial assets carrying value.

+ References

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- Definition

Financial Liabilities carrying value.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 7, 8, 9, 10

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

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-Name Regulation S-X (SX)

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- Definition

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

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- Definition

This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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