Percentage of Revenue by Geographic Area (Detail) (Total Revenue)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Concentration Risk [Line Items]
Revenues, percentage by country	100.00%	100.00%	100.00%	100.00%
Sweden
Concentration Risk [Line Items]
Revenues, percentage by country	48.00%	39.00%	44.00%	39.00%
United States
Concentration Risk [Line Items]
Revenues, percentage by country	23.00%	46.00%	32.00%	47.00%
United Kingdom
Concentration Risk [Line Items]
Revenues, percentage by country	25.00%	13.00%	21.00%	12.00%
Other
Concentration Risk [Line Items]
Revenues, percentage by country	4.00%	2.00%	3.00%	2.00%