Acquisitions (Components of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified				6 Months Ended	12 Months Ended	0 Months Ended		6 Months Ended	12 Months Ended	0 Months Ended				6 Months Ended	12 Months Ended	0 Months Ended
	Jun. 30, 2014 Synchronite, LLC [Member]	Jun. 02, 2014 Synchronite, LLC [Member]	Nov. 09, 2012 Engage Pty Ltd. [Member]	Jun. 30, 2014 Technology [Member]	Dec. 31, 2013 Technology [Member]	Jun. 02, 2014 Technology [Member] Synchronite, LLC [Member]	Nov. 09, 2012 Technology [Member] Engage Pty Ltd. [Member]	Jun. 30, 2014 Trade Names [Member]	Dec. 31, 2013 Trade Names [Member]	Jun. 02, 2014 Trade Names [Member] Synchronite, LLC [Member]	Nov. 09, 2012 Trade Names [Member] Engage Pty Ltd. [Member]	Jun. 02, 2014 Customer Relationships [Member] Synchronite, LLC [Member]	Nov. 09, 2012 Customer Relationships [Member] Engage Pty Ltd. [Member]	Jun. 30, 2014 Non-compete Agreements [Member]	Dec. 31, 2013 Non-compete Agreements [Member]	Jun. 02, 2014 Non-compete Agreements [Member] Synchronite, LLC [Member]	Nov. 09, 2012 Non-compete Agreements [Member] Engage Pty Ltd. [Member]
Business Acquisition [Line Items]
Weighted Average Amortization Period				4 years 1 month 18 days	3 years 9 months 18 days	120 months	36 months	2 years 9 months 12 days	2 years 8 months 12 days	48 months	12 months	84 months	48 months	1 year 3 months 12 days	1 year 2 months 12 days	36 months	12 months
Intangible assets	$ 1,450	$ 1,451	$ 3,600			$ 1,082	$ 768			$ 62	$ 95	$ 247	$ 2,661			$ 60	$ 76