Other Liabilities (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Accrued liabilities
Employee compensation	$ 13,699,000	$ 13,341,000
Working capital adjustment due to EyeWonder seller	2,799,000	10,244,000
Taxes payable	7,192,000	1,738,000
Installment payment due to Peer 39 seller	2,331,000
Revenue earnout	2,430,000	469,000
Acquisition exit costs (office closures)	407,000	860,000
Other	9,433,000	7,226,000
Total	38,291,000	33,878,000
Other non-current liabilities
Deferred rent	10,032,000	549,000
Israeli statutory employee compensation	5,575,000	4,057,000
Revenue earnout	427,000	1,204,000
Other	288,000	1,429,000
Total	16,322,000	7,239,000
Additional disclosures
Office lease term	15 years
Free rent period	21 months
Leasehold improvements contribution received from landlord	$ 5,600,000