Cash, Cash Equivalents and Investments (Tables)

3 Months Ended

Mar. 31, 2013

Cash, Cash Equivalents and Investments [Abstract]

Cash and investments

	March 31, 2013		December 31, 2012
Cash	$	13,886	$	13,059
Cash equivalents		1,708		4,500
Short-term investments		36,407		33,596
	$	52,001	$	51,155

Cash equivalents and Level 1 investments measured at fair value

	March 31, 2013								December 31, 2012
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds and other cash equivalents	$	1,708	$	0	$	0	$	1,708	$	4,500	$	0	$	0	$	4,500
Investments:
Certificate of deposits		3,597		0		0		3,597		5,062		0		0		5,062
US government agency bonds		0		9,891		0		9,891		0		8,498		0		8,498
Municipal bonds		0		12,060		0		12,060		0		10,162		0		10,162
Corporate debt securities		0		10,859		0		10,859		0		9,880		0		9,880
Total	$	5,305	$	32,810	$	0	$	38,115	$	9,562	$	28,540	$	0	$	38,102