Segment and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Summary of Revenue and Long-lived Assets

Information regarding revenue for the three years ended December 31, 2017, 2016 and 2015 and long-lived assets as of December 31, 2017 and 2016 follows:

	Year Ended December 31,
	2017		2016		2015
	(In thousands)
Revenues
United States	$	336,867	$	314,343	$	262,558
United Kingdom		59,151		54,015		39,338
Other		1,453		1,561		1,202
Total	$	397,471	$	369,919	$	303,098

	As of December 31,
	2017		2016
	(In thousands)
Long-lived assets, as defined
United States	$	27,990	$	23,370
United Kingdom		10,532		7,713
Other		26		21
Total	$	38,548	$	31,104