Acquisitions and Exit Activities Exit Activities (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Asset impairment charges	$ 836,000	$ 1,430,000	$ 958,000
Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	1,000,000
Restructuring and Related Cost, Incurred Cost	300,000
Asset impairment charges	300,000
Restructuring Charges	300,000
Restructuring and Related Cost, Expected Cost Remaining	400,000
Facility Closing | Product and content development
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	26,000
Facility Closing | Sales and marketing
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	60,000
Facility Closing | General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 179,000