Description of Business and Summary of Significant Accounting Policies - Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 ProductService_Groups	Sep. 30, 2011
Segment Reporting Information [Line Items]
Document Period End Date			Sep. 30, 2012
Total revenue, international percentage			29.10%	28.50%
Number of product/service groups			4
Operating revenue	$ 53,804	$ 42,602	$ 145,347	$ 124,919
Exchanges [Member]
Segment Reporting Information [Line Items]
Operating revenue	43,592	33,021	116,420	96,308
Broker Systems [Member]
Segment Reporting Information [Line Items]
Operating revenue	4,537	4,731	13,713	13,397
BPO [Member]
Segment Reporting Information [Line Items]
Operating revenue	4,252	3,576	11,713	10,948
Carrier Systems [Member]
Segment Reporting Information [Line Items]
Operating revenue	$ 1,423	$ 1,274	$ 3,501	$ 4,266