Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2011

Fair Value Measurements

Assets Measured at Fair Value on a Recurring Basis

As of June 30, 2011	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		June 30, 2011
Cash equivalents (1)	$	5,119	$	—	$	—	$	5,119
Short-term investments (2) (3)		205		—		450		655
Total	$	5,324	$	—	$	450	$	5,774

As of December 31, 2010	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		December 31, 2010
Cash equivalents (1)	$	139,010	$	—	$	—	$	139,010
Short-term investments (2) (3)		40		—		450		490
Long-term investments (4)		—		—		2,254		2,254
Total	$	139,050	$	—	$	2,704	$	141,754

(1)	Cash equivalents consist of money market funds with original maturity dates of three months or less, for which we determine fair value through quoted market prices.
(2)	As of June 30, 2011 and December 31, 2010, Level 1 short-term investments include investments in tax-advantaged preferred securities, for which we determined fair value based on the quoted market prices of underlying securities.
(3)	Level 3 short-term investments include an auction rate security invested in a tax-exempt state government obligation that was valued at par with a value of $0.4 million, or 0.1% of our total assets, as of both June 30, 2011 and December 31, 2010. Our intent is not to hold the auction rate security invested in a tax-exempt state government obligation to maturity, but rather to use the interest reset feature to provide liquidity. However, should the marketplace auctions continue to fail we may hold the security to maturity, which is September 2011. In October 2010, $1.1 million of this security was redeemed by the issuer at par.
(4)	Level 3 long-term investments as of December 31, 2010 included a tax-advantaged preferred stock of a financial institution with a fair value of $2.3 million, or 0.5% of total assets. As of December 31, 2010, it was uncertain whether we would be able to liquidate these securities within the next twelve months; as such we classified them as long-term on our consolidated balance sheet. Due to the lack of observable market quotes we utilized valuation models that relied exclusively on Level 3 inputs including those that are based on expected cash flow streams, including assessments of counterparty credit quality, default risk underlying the security, discount rates and overall capital market liquidity. In June 2011, we sold this security for approximately $2.5 million and recorded a gain of approximately $0.4 million in our consolidated statement of operations.

Reconciliation of Beginning and Ending Balances for Level 3 Investments

Balance as of January 1, 2010	$	3,971
Unrealized loss on securities recorded in other comprehensive income		(167	)
Partial redemption of auction rate security (3)		(1,100	)
Balance as of December 31, 2010		2,704
Sale of tax-advantaged preferred stock (4)		(2,485	)
Realized gain on securities included in the statement of operations (4)		409
Reversal of unrealized gain on securities sold recorded in other comprehensive income		(178	)
Balance as of June 30, 2011	$	450