Discontinued Operations - Results from Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other income (expense):
Income tax provision	$ 8,700		$ 9,800
Loss from discontinued operations, net of applicable taxes	(3,658)	$ (3,267)	(9,351)	$ (3,983)
International operations | Discontinued operations, disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	18,043	11,309	40,146	38,679
Cost of revenues	11,469	4,111	19,694	13,060
Amortization of acquired intangible assets	555	376	1,291	1,093
Gross profit	6,019	6,822	19,161	24,526
Operating (income) expenses:
Research and development	16	48	50	123
Sales and marketing	2,865	4,360	12,391	14,109
General and administrative	1,440	1,553	5,079	4,894
Amortization of acquired intangible assets	155	241	622	971
Goodwill and intangible impairment	0	908	0	908
Restructuring expenses	4	(16)	620	(188)
Net gain on sale of business	(5,361)	0	(5,361)	0
Total operating (income) expenses	(881)	7,094	13,401	20,817
Operating income (loss)	6,900	(272)	5,760	3,709
Other income (expense):
Interest income	12	15	46	29
Interest expense	(2,156)	(2,142)	(7,240)	(6,504)
Other income (expense), net	243	(102)	1,892	(451)
Total other income (expense)	(1,901)	(2,229)	(5,302)	(6,926)
Income (loss) from discontinued operations before taxes	4,999	(2,501)	458	(3,217)
Income tax provision	8,657	766	9,809	766
Loss from discontinued operations, net of applicable taxes	$ (3,658)	$ (3,267)	$ (9,351)	$ (3,983)