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Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2013

Available-for-sale Securities [Abstract]

Cash equivalents and marketable securities classified as available-for-sale

All cash equivalents and marketable securities are classified as available-for-sale. Total cash, cash equivalents and marketable securities are summarized as follows:

		As of September 30, 2013
(In thousands)		Fair Value				Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Weighted Rate of Return
Money market funds		$	295,211			$	295,211			$	—			$	—			0.01	%
Corporate notes, bonds and commercial paper		58,396				58,406				—				(10		)		0.14	%
Total cash equivalents and marketable securities		353,607				353,617				—				(10		)
Cash		12,750				12,750				—				—
Total cash, cash equivalents and marketable securities		$	366,357			$	366,367			$	—			$	(10	)

		As of December 31, 2012
(In thousands)		Fair Value				Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Weighted Rate of Return
Money market funds		$	126,570			$	126,570			$	—			$	—			0.01	%
Corporate notes, bonds and commercial paper		57,345				57,356				4				(15		)		0.17	%
Total cash equivalents and marketable securities		183,915				183,926				4				(15		)
Cash		19,415				19,415				—				—
Total cash, cash equivalents and marketable securities		$	203,330			$	203,341			$	4			$	(15	)

Available-for-sale securities reported at fair value

Available-for-sale securities are reported at fair value on the balance sheets and classified as follows:

	As of
	September 30, 2013				December 31, 2012
	(In thousands)
Cash equivalents	$	295,211			$	129,569
Short term marketable securities	58,396				54,346
Total cash equivalents and marketable securities	353,607				183,915
Cash	12,750				19,415
Total cash, cash equivalents and marketable securities	$	366,357			$	203,330

Estimated fair value of cash equivalents and marketable securities classified by the length of time that the securities have been in a continuous unrealized loss position

The estimated fair value of cash equivalents and marketable securities classified by the length of time that the securities have been in a continuous unrealized loss position at September 30, 2013 and December 31, 2012 are as follows:

	Fair Value								Gross Unrealized Loss
	September 30, 2013				December 31, 2012				September 30, 2013				December 31, 2012
	(In thousands)
Less than one year
Corporate notes, bonds and commercial paper	$	50,369			$	51,819			$	(10	)		$	(15	)

X

- Definition

Tabular disclosure of cash and the reconciliation of available-for-sale securities from cost basis to fair value.

+ References

No definition available.

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- Definition

Tabular disclosure of the components of cash, cash equivalents, and short-term investments. Short-term investments may include current marketable securities.

+ References

No definition available.

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- Definition

For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563

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