Information about Geographic Areas (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Total revenue:
Total revenue	$ 24,505	$ 23,422	$ 50,053	$ 49,430
Long-lived assets:
Total long-lived assets	9,384		9,384		9,464
North America [Member]
Total revenue:
Total revenue	17,804	18,347	35,764	37,703
Long-lived assets:
Total long-lived assets	4,363		4,363		4,334
Asia [Member]
Total revenue:
Total revenue	5,456	4,368	11,218	10,050
Long-lived assets:
Total long-lived assets	144		144		111
Europe [Member]
Total revenue:
Total revenue	1,244	677	3,044	1,634
Long-lived assets:
Total long-lived assets	4,877		4,877		5,019
Other foreign [Member]
Total revenue:
Total revenue	$ 1	$ 30	$ 27	$ 43