Information about Geographic Areas (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Total revenue:
Total revenue	$ 21,837	$ 24,505	$ 42,707	$ 50,053
Long-lived assets:
Total long-lived assets	8,437		8,437		8,813
North America [Member]
Total revenue:
Total revenue	19,757	20,289	38,839	40,426
Long-lived assets:
Total long-lived assets	3,408		3,408		3,663
Asia [Member]
Total revenue:
Total revenue	846	3,077	1,750	7,142
Long-lived assets:
Total long-lived assets	424		424		447
Europe [Member]
Total revenue:
Total revenue	1,234	1,139	2,118	2,485
Long-lived assets:
Total long-lived assets	$ 4,605		$ 4,605		$ 4,703