Income Taxes - Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Deferred tax assets:
Foreign net operating loss carryforwards	$ 1,936	$ 4,762
State income taxes	565	651
Accruals and allowances	697	500
Stock based compensation	1,094	618
Capital loss	1,754	1,754
Deferred revenue	790	631
Deferred rent	302	219
Property, equipment and intangible assets	7	0
Total deferred tax assets	7,145	9,135
Valuation allowance	(2,886)	(6,516)
Total deferred tax assets net of valuation allowance	4,259	2,619
Deferred tax liabilities:
Deferred Tax Liabilities, Undistributed Foreign Earnings	(355)	(251)
Deferred Tax Liabilities, Property, Plant and Equipment	0	(270)
Deferred Tax Liabilities, Net	(355)	(521)
Deferred Tax Assets, Net	$ 3,904	$ 2,098