Cash and Investments (Tables)

3 Months Ended

Mar. 26, 2016

Investments Debt And Equity Securities [Abstract]

Cash, Cash Equivalents and Available-for-Sale Investments

The following tables present cash, cash equivalents, and available-for-sale investments as of the following dates (in thousands):

	March 26, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Market Value
Cash	$	33,145	$	—	$	—		$	33,145
Cash equivalents:
Money market funds		1,075		—		—			1,075
Commercial paper and corporate debt securities		4,452		—		—			4,452
Marketable securities:
Commercial paper		699		—		—			699
U.S. Treasury securities		6,971		2		—			6,973
U.S. Government agency securities		23,231		4		(8	)		23,227
Municipal securities		2,634		—		(3	)		2,631
Corporate debt securities		11,147		2		(6	)		11,143
Total cash, cash equivalents, and marketable securities	$	83,354	$	8	$	(17	)	$	83,345
	December 26, 2015
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Market Value
Cash	$	32,996	$	—	$	—		$	32,996
Cash equivalents:
Money market funds		590		—		—			590
Commercial paper and corporate debt securities		4,568		—		—			4,568
Marketable securities:
Commercial paper		1,884		—		—			1,884
U.S. Treasury securities		4,411		—		(10	)		4,401
U.S. Government agency securities		20,193		1		(29	)		20,165
Municipal securities		3,747		1		(3	)		3,745
Corporate debt securities		14,759		—		(23	)		14,736
Total cash, cash equivalents, and marketable securities	$	83,148	$	2	$	(65	)	$	83,085