Cash cash equivalents and short term investments fair value disclosure.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.2)

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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

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-Publisher FASB

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-Topic 320

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-Section 25

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- Definition

Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Topic 210

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-Topic 230

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-Section 45

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-Glossary Cash Equivalents

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-Topic 210

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-Subparagraph (SX 210.5-02.1)

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- Definition

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.

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Cash 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 customer may deposit additional funds at any time and 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. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

+ References

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

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-Glossary Cash Equivalents

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-Topic 210

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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.

+ References

No definition available.

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Available for Sale Securities - Summary of Available for Sale Securities at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 76,568	$ 76,194
Gross Unrealized Gains	12	4
Gross Unrealized Losses	(39)	(60)
Fair Value	76,541	76,138
Cash and cash equivalents	76,248	32,780	$ 95,394	$ 21,215
Cash and cash equivalents, fair value	76,248	32,780
Total cash, cash equivalents, and available for sale securities - Amortized Cost	152,816	108,974
Cash and cash equivalents and available for sale securities	152,789	108,918
Certificates of deposit
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	19,721	13,429
Fair Value	19,721	13,429
U.S. Government debt securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	38,546	38,412
Gross Unrealized Gains	10	1
Gross Unrealized Losses	(14)	(28)
Fair Value	38,542	38,385
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		2,499
Fair Value		2,499
Corporate debt securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	18,301	21,854
Gross Unrealized Gains	2	3
Gross Unrealized Losses	(25)	(32)
Fair Value	18,278	21,825
Cash And Money Market Account
Schedule Of Available For Sale Securities [Line Items]
Cash and cash equivalents	76,248	32,780
Cash and cash equivalents, fair value	$ 76,248	$ 32,780