Investments (Tables)

6 Months Ended

Jun. 25, 2016

Amortized Cost and Fair Value of Available for Sale Investments

The amortized cost and fair values of available-for-sale investments are as follows at June 25, 2016 and December 26, 2015 (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
June 25, 2016
Money market investments	$	11,864	$	—	$	—	$	11,864
Asset-backed securities		4,430		10		15		4,425
Corporate bonds and direct obligations of government agencies		73,608		520		64		74,064
U.S. Treasury obligations		19,031		18		—		19,049
Total	$	108,933	$	548	$	79	$	109,402
December 26, 2015
Money market investments	$	7,594	$	—	$	—	$	7,594
Asset-backed securities		4,523		1		58		4,466
Corporate bonds and direct obligations of government agencies		76,839		190		270		76,759
U.S. Treasury obligations		19,273		5		13		19,265
Total	$	108,229	$	196	$	341	$	108,084

Schedule of Unrealized Loss on Available for Sale Investments

For those available-for-sale investments with unrealized losses at June 25, 2016 and December 26, 2015, the following table summarizes the duration of the unrealized loss (in thousands):

	Less than 12 months				12 months or longer				Total
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
June 25, 2016
Asset-backed securities	$	—	$	—	$	2,459	$	15	$	2,459	$	15
Corporate bonds and direct obligations of government agencies		5,326		3		1,481		61		6,807		64
Total	$	5,326	$	3	$	3,940	$	76	$	9,266	$	79
December 26, 2015
Asset-backed securities	$	4,422	$	58	$	—	$	—	$	4,422	$	58
Corporate bonds and direct obligations of government agencies		39,276		217		562		53		39,838		270
U.S. Treasury obligations		15,093		13		—		—		15,093		13
Total	$	58,791	$	288	$	562	$	53	$	59,353	$	341