v2.4.0.6

Financial Statement Details (Short Term Marketable Securities, Available for Sale) (Details) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Financial Statement Details [Line Items]
Amortized Cost	$ 79,359,000	$ 42,233,000
Gross Unrealized Gains	13,000	3,000
Gross Unrealized Losses	(14,000)	(12,000)
Estimated Market Value	79,358,000	42,224,000
U.S. Government Agencies [Member]
Financial Statement Details [Line Items]
Amortized Cost	61,890,000	32,231,000
Gross Unrealized Gains	11,000	2,000
Gross Unrealized Losses	(5,000)	(10,000)
Estimated Market Value	61,896,000	32,223,000
Commercial Paper [Member]
Financial Statement Details [Line Items]
Amortized Cost	7,497,000	4,996,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Market Value	7,497,000	4,996,000
Corporate Debt [Member]
Financial Statement Details [Line Items]
Amortized Cost	9,972,000	5,006,000
Gross Unrealized Gains	2,000	1,000
Gross Unrealized Losses	(9,000)	(2,000)
Estimated Market Value	$ 9,965,000	$ 5,005,000

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Accounting Standards Codification

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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 represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Subparagraph b

-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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