Investments (Tables)

9 Months Ended

Sep. 24, 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 September 24, 2016 and December 26, 2015 (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
September 24, 2016
Money market investments	$	7,268	$	—	$	—	$	7,268
Asset-backed securities		4,224		6		9		4,221
Corporate bonds and direct obligations of government agencies		77,216		449		46		77,619
U.S. Treasury obligations		20,557		17		1		20,573
Total	$	109,265	$	472	$	56	$	109,681
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 September 24, 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
September 24, 2016
Asset-backed securities	$	1,482	$	1	$	2,395	$	8	$	3,877	$	9
Corporate bonds and direct obligations of government agencies		13,947		23		1,394		23		15,341		46
U.S. Treasury obligations		4,017		1		—		—		4,017		1
Total	$	19,446	$	25	$	3,789	$	31	$	23,235	$	56
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