Fair Value Measurements - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 22,325	$ 32,212
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent Consideration Business acquisition	The expected number of shares to be issued in each year depends on the probability of Blammo achieving the Net Revenue targets, and the Company used a risk-neutral framework to estimate the probability of achieving these revenue targets for each year. The fair value of the contingent consideration was determined using a digital option, which captures the present value of the expected payment multiplied by the probability of reaching the revenue targets for each year.
Discount rate percent	35.00%	25.00%
Volatility percent	38.00%	53.00%
Fair value of contingent liabilities	2,512	796
Fair value of contingent consideration recognized as a current liability	$ 1,855
Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Risk free rate	0.05%	0.15%
Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Risk free rate	0.28%	0.42%