Revenues in Geographic Regions Restated (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								6 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2012	Jun. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 26,311	$ 26,099	$ 29,264	$ 26,509	$ 17,724	$ 19,253	$ 19,436	$ 17,612	$ 55,773	$ 37,048	$ 81,872	$ 56,301	$ 108,183	$ 74,025	$ 66,804
United States of America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues													57,816	36,765	30,226
Americas, excluding the USA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues													5,051	6,528	9,713
EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues													22,381	20,621	17,917
APAC
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues													$ 22,935	$ 10,111	$ 8,948