Long Lived Assets by Geographic Area (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 30,827	$ 14,458
Long-lived assets percentage	100.00%	100.00%
U.S.
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	22,693	9,624
Long-lived assets percentage	73.00%	67.00%
India
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	5,461	2,391
Long-lived assets percentage	18.00%	16.00%
International, other
Long-Lived Assets by Geographical Areas [Line Items]
Long-lived assets	$ 2,673	$ 2,443
Long-lived assets percentage	9.00%	17.00%