Financial Instruments

We invest our excess cash in a variety of marketable securities, which are all classified as available-for-sale. The following summarizes our cash and cash equivalents, restricted cash and cash equivalents and marketable securities by financial instrument category as of the respective period ends:



	February 29, 2016
($ in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents⁽¹⁾		Current Marketable Securities		Noncurrent Marketable Securities
Cash	$	426,916	$	—	$	—		$	426,916	$	426,916	$	—	$	—
Level 1:
Money market funds	124,061		—		—			124,061		124,061		—		—
Level 2:
Corporate bonds	120,895		10		(449		)	120,456		—		96,787		23,669
Tax-exempt municipal bonds	89,047		113		(15		)	89,145		2,395		64,162		22,588
Time deposits	50,392		—		—			50,392		25,154		25,238		—
Other	34,872		5		(16		)	34,861		1,000		28,851		5,010
Total	$	846,183	$	128	$	(480	)	$	845,831	$	579,526	$	215,038	$	51,267



	August 31, 2015
($ in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents⁽¹⁾		Current Marketable Securities		Noncurrent Marketable Securities
Cash	$	564,225	$	—	$	—		$	564,225	$	564,225	$	—	$	—
Level 1:
Money market funds	107,408		—		—			107,408		107,408		—		—
Level 2:
Corporate bonds	137,283		16		(271		)	137,028		1,823		82,047		53,158
Tax-exempt municipal bonds	97,022		68		(60		)	97,030		2,408		61,530		33,092
Time deposits	50,267		—		—			50,267		25,110		25,157		—
Other	36,634		10		(37		)	36,607		1,100		25,942		9,565
Total	$	992,839	$	94	$	(368	)	$	992,565	$	702,074	$	194,676	$	95,815

⁽¹⁾ Cash and cash equivalents includes restricted cash and cash equivalents.

We measure our financial instruments at fair value on a recurring basis as follows:


•	Money market funds - We use Level 1 inputs that primarily consist of real-time quotes for transactions in active exchange markets involving identical assets.


•	Other financial instruments - We use a market approach with Level 2 observable inputs for all other securities. The Level 2 inputs include quoted prices for similar assets in active markets, or quoted prices for identical or similar assets in markets that are not active.

Our marketable securities have maturities that occur within three years. We may sell certain of our marketable securities prior to their stated maturities for strategic reasons including, but not limited to, investment yield and credit risk management. We have not recognized significant gains or losses related to such sales.