Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases and Issues

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- Definition

Potential Obligation Fair Value Disclosure

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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.

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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

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7, 8, 9, 10

-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 95

-Paragraph 7

-Footnote 1

-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 95

-Paragraph 8

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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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph a

-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

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- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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-Publisher FASB

-Name Accounting Standards Codification

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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 SEC

-Name Regulation S-X (SX)

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FAIR VALUE MEASUREMENTS (Details) (USD $) In Thousands																															9 Months Ended
FAIR VALUE MEASUREMENTS (Details) (USD $) In Thousands	Sep. 30, 2011 Estimate of Fair Value, Fair Value Disclosure [Member]	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure [Member]	Sep. 30, 2011 Estimate of Fair Value, Fair Value Disclosure [Member] Commercial paper [Member]	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure [Member] Commercial paper [Member]	Sep. 30, 2011 Estimate of Fair Value, Fair Value Disclosure [Member] Money market funds [Member]	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure [Member] Money market funds [Member]	Sep. 30, 2011 Estimate of Fair Value, Fair Value Disclosure [Member] Certificates of Deposit [Member]	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure [Member] U.S. government debt securities [Member]	Sep. 30, 2011 Estimate of Fair Value, Fair Value Disclosure [Member] Corporate securities [Member]	Dec. 31, 2010 Estimate of Fair Value, Fair Value Disclosure [Member] Corporate securities [Member]	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Commercial paper [Member]	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Commercial paper [Member]	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Money market funds [Member]	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Money market funds [Member]	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Certificates of Deposit [Member]	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. government debt securities [Member]	Sep. 30, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate securities [Member]	Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate securities [Member]	Sep. 30, 2011 Significant Other Observable Inputs (Level 2) [Member]	Dec. 31, 2010 Significant Other Observable Inputs (Level 2) [Member]	Sep. 30, 2011 Significant Other Observable Inputs (Level 2) [Member] Commercial paper [Member]	Dec. 31, 2010 Significant Other Observable Inputs (Level 2) [Member] Commercial paper [Member]	Sep. 30, 2011 Significant Other Observable Inputs (Level 2) [Member] Money market funds [Member]	Dec. 31, 2010 Significant Other Observable Inputs (Level 2) [Member] Money market funds [Member]	Sep. 30, 2011 Significant Other Observable Inputs (Level 2) [Member] Certificates of Deposit [Member]	Dec. 31, 2010 Significant Other Observable Inputs (Level 2) [Member] U.S. government debt securities [Member]	Sep. 30, 2011 Significant Other Observable Inputs (Level 2) [Member] Corporate securities [Member]	Dec. 31, 2010 Significant Other Observable Inputs (Level 2) [Member] Corporate securities [Member]	Sep. 30, 2011 Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure			$ 7,000	$ 7,135	$ 33,827	$ 52,951	$ 10,000						$ 0	$ 0	$ 33,827	$ 52,951	$ 0						$ 7,000	$ 7,135	$ 0	$ 0	$ 10,000
Investments, Fair Value Disclosure								6,100	63,954	54,523								0	0	0								6,100	63,954	54,523
Assets, Fair Value Disclosure	114,781	120,709									33,827	52,951									80,954	67,758
Potential Obligation Fair Value Disclosure	0
Obligations, Fair Value Disclosure																					0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance																															0
Purchases and issuances																															3,000
Settlements																															(3,000)
Ending balance																															$ 0