Fair Value Measurements

12 Months Ended

Jun. 30, 2011

Fair Value Measurements [Abstract]

Fair Value Measurements

3.  Fair Value Measurements

We use a three-level valuation hierarchy for measuring fair value and include detailed financial statement disclosures about fair value measurements. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

•     Level 1: Inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities in active markets.

•     Level 2: Inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument.

•     Level 3: Inputs to the valuation methodology are unobservable and significant to the fair value measurement.

A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

The following tables summarize, by major security type, our assets that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy:

	June 30, 2011
			Quoted Prices in
			Active				Significant
			Markets for		Significant Other		Unobservable
			Identical Assets		Observable Inputs		Inputs
	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	236,552	$	236,552	$	—	$	—
Auction rate security		529		—		—		529
Total assets recorded at fair value	$	237,081	$	236,552	$	—	$	529

	June 30, 2010
			Quoted Prices in
			Active				Significant
			Markets for		Significant Other		Unobservable
			Identical Assets		Observable Inputs		Inputs
	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents	$	162,727	$	162,727	$	—	$	—
Corporate debt securities		6,745		6,745		—		—
U.S. government and agency securities		1,900		1,900		—		—
Certificates of deposit		959		959		—		—
Auction rate security		660		—		—		660
Total assets recorded at fair value	$	172,991	$	172,331	$	—	$	660

The following table presents a roll forward of assets measured at fair value using significant unobservable inputs (Level 3) at June 30, 2011 and 2010:

Balance at June 30, 2009	$	760
Maturities or redemptions		(100	)
Balance at June 30, 2010	$	660
Maturities or redemptions		(100	)
Reclassification of unrealized loss to net income		40
Realized loss		(71	)
Balance at June 30, 2011	$	529