Information about Geographic Areas (Tables)

3 Months Ended

Mar. 31, 2012

Revenue by Geography

	Three Months Ended March 31,
	2011		2012
	(unaudited)
Revenues:
United States	$	4,005	$	4,874
United Kingdom		969		1,150
Rest of the world		3,601		4,621
Total revenues	$	8,575	$	10,645

Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country

	As of December 31, 2011		As of March 31, 2012
			(unaudited)
Long-lived assets:
United States	$	15,963	$	16,016
International		3,853		4,269
Total long-lived assets	$	19,816	$	20,285