Fair Value Measurements

6 Months Ended

May 31, 2012

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value Measurements

The following table details the fair value measurements within the fair value hierarchy of our financial assets at May 31, 2012 (in thousands):

				Fair Value Measurements Using
	Total Fair Value			Level 1		Level 2			Level 3
Money market funds	$	29,832		$	29,832	$	—		$	—
State and municipal bond obligations	78,215			—		78,215			—
Auction rate securities – municipal bonds	23,371			—		—			23,371
Auction rate securities – student loans	10,777			—		2,700			8,077
Corporate bonds	6,449			—		6,449			—
Foreign exchange derivatives	(172		)	—		(172		)	—

The following table details the fair value measurements within the fair value hierarchy of our financial assets at November 30, 2011 (in thousands):

			Fair Value Measurements Using
	Total Fair Value		Level 1		Level 2		Level 3
Money market funds	$	24,220	$	24,220	$	—	$	—
State and municipal bond obligations	84,398		—		84,398		—
Brazilian mutual funds	15,346		15,346		—		—
Auction rate securities – municipal bonds	22,931		—		—		22,931
Auction rate securities – student loans	10,608		—		—		10,608
Corporate bonds	2,562		—		2,562		—
Foreign exchange derivatives	52		—		52		—

When developing fair value estimates, we maximize the use of observable inputs and minimize the use of unobservable inputs. When available, we use quoted market prices to measure fair value. If market prices are not available, the fair value measurement is based on models that use primarily market based parameters including yield curves, volatilities, credit ratings and currency rates. In certain cases where market rate assumptions are not available, we are required to make judgments about assumptions market participants would use to estimate the fair value of a financial instrument.

The valuation technique used to measure fair value for our Level 1 and Level 2 assets is a market approach, using prices and other relevant information generated by market transactions involving identical or comparable assets.

The valuation technique used to measure fair value for our Level 3 assets, which consists of our ARS, is an income approach, where the expected weighted average future cash flows are discounted back to present value for each asset. The significant unobservable inputs used in the fair value measurement of our ARS are the probability of earning the maximum rate until maturity, the probability of principal return prior to maturity, the probability of default, the liquidity risk premium and the recovery rate in default. Changes in the underlying assumptions used to value the ARS could significantly impact the fair value estimates recorded in the condensed consolidated balance sheets.

The following table reflects the activity for our financial assets measured at fair value using Level 3 inputs for each period presented (in thousands):

	Three Months Ended						Six Months Ended
	May 31, 2012			May 31, 2011			May 31, 2012			May 31, 2011
Balance, beginning of period	$	33,343		$	39,839		$	33,539		$	39,643
Redemptions and repurchases	—			(6,000		)	(225		)	(6,200		)
Transfer to Level 2 fair value measurement	(2,700		)	—			(2,700		)	—
Unrealized gains included in accumulated other comprehensive loss	805			945			834			1,341
Balance, end of period	$	31,448		$	34,784		$	31,448		$	34,784

During the second quarter of fiscal 2012, we received a redemption notice for one of our ARS at par value. We transferred the ARS to a Level 2 fair value measurement, as the value at May 31, 2012 is based on observable inputs.