Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Operating revenue	$ 92,800	$ 74,608	$ 259,290	$ 218,248
Operating expenses:
Cost of services provided	34,937	22,425	91,056	62,606
Product development	8,536	8,563	25,303	24,913
Sales and marketing	3,833	4,463	12,312	13,002
General and administrative	14,874	12,126	42,156	37,019
Amortization and depreciation	2,709	2,738	8,323	8,088
Total operating expenses	64,889	50,315	179,150	145,628
Operating income	27,911	24,293	80,140	72,620
Interest income	375	635	1,614	1,219
Interest expense	(3,552)	(1,922)	(9,038)	(5,381)
Non-operating income, gain on joint venture investment (see Note 8)	0	1,162	0	1,162
Foreign currency exchange gain (loss)	(400)	578	2,705	852
Income before income taxes	24,334	24,746	75,421	70,472
Income tax (expense) benefit	204	(789)	(363)	(1,121)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	24,538	23,957	75,058	69,351
Net Income (Loss) Attributable to Noncontrolling Interest	354	(110)	1,013	133
Net Income (Loss) Attributable to Parent	$ 24,184	$ 24,067	$ 74,045	$ 69,218
Basic earnings per common share	$ 0.77	$ 0.74	$ 2.34	$ 2.12
Diluted earnings per common share	$ 0.76	$ 0.74	$ 2.33	$ 2.10
Basic weighted average shares outstanding	31,453	32,421	31,582	32,716
Diluted weighted average shares outstanding	31,622	32,705	31,743	32,994