Investments (Tables)

9 Months Ended

Sep. 27, 2014

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 27, 2014 and December 28, 2013 (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
September 27, 2014
Money market investments	$	1,168	$	—	$	—	$	1,168
Asset-backed securities		5,450		3		55		5,398
Corporate bonds and direct obligations of government agencies		76,924		689		221		77,392
U.S. Treasury obligations		19,516		24		8		19,532
Total	$	103,058	$	716	$	284	$	103,490
December 28, 2013
Money market investments	$	2,499	$	—	$	—	$	2,499
Asset-backed securities		4,350		19		72		4,297
Corporate bonds and direct obligations of government agencies		76,786		783		370		77,199
U.S. Treasury obligations		18,524		31		13		18,542
Total	$	102,159	$	833	$	455	$	102,537

Schedule of Unrealized Loss on Available for Sale Investments

For those available-for-sale investments with unrealized losses at September 27, 2014 and December 28, 2013, 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 27, 2014
Asset-backed securities	$	2,652	$	13	$	2,445	$	42	$	5,097	$	55
Corporate bonds and direct obligations of government agencies		13,264		59		11,385		162		24,649		221
U.S. Treasury obligations		—		—		760		8		760		8
Total	$	15,916		72	$	14,590	$	212	$	30,506	$	284
December 28, 2013
Asset -backed securities	$	3,429	$	72	$	—	$	—	$	3,429	$	72
Corporate bonds and direct obligations of government agencies		22,169		370		—		—		22,169		370
U.S. Treasury obligations		757		13		—		—		757		13
Total	$	26,355	$	455	$	—	$	—	$	26,355	$	455