Intangible Assets (Details 1) - Intangible Assets, Other Than Goodwill (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Intangible assets, other than goodwill
Gross carrying amount	$ 64,487,000	$ 54,555,000
Accumulated amortization	(40,607,000)	(30,753,000)
Net carrying amount	23,880,000	23,802,000
Amortization expense
Amortization expense on intangibles	9,800,000	8,900,000	5,600,000
Minimum
Intangible assets, other than goodwill
Estimated useful lives of intangible assets	2 years
Maximum
Intangible assets, other than goodwill
Estimated useful lives of intangible assets	5 years
Licenses
Intangible assets, other than goodwill
Gross carrying amount	31,443,000	30,620,000
Accumulated amortization	(21,216,000)	(16,826,000)
Net carrying amount	10,227,000	13,794,000
Purchased technologies
Intangible assets, other than goodwill
Gross carrying amount	13,180,000	8,762,000
Accumulated amortization	(7,428,000)	(5,062,000)
Net carrying amount	5,752,000	3,700,000
Domain name purchases
Intangible assets, other than goodwill
Gross carrying amount	442,000	446,000
Accumulated amortization	(442,000)	(441,000)
Net carrying amount	0	5,000
Non-compete agreements
Intangible assets, other than goodwill
Gross carrying amount	2,165,000	1,900,000
Accumulated amortization	(1,613,000)	(1,186,000)
Net carrying amount	552,000	714,000
Customer relationships
Intangible assets, other than goodwill
Gross carrying amount	6,137,000	5,725,000
Accumulated amortization	(5,442,000)	(4,477,000)
Net carrying amount	695,000	1,248,000
Trademarks, tradenames and patents
Intangible assets, other than goodwill
Gross carrying amount	3,581,000	3,062,000
Accumulated amortization	(1,985,000)	(1,671,000)
Net carrying amount	1,596,000	1,391,000
Other
Intangible assets, other than goodwill
Gross carrying amount	7,539,000	4,040,000
Accumulated amortization	(2,481,000)	(1,090,000)
Net carrying amount	$ 5,058,000	$ 2,950,000