ACQUISITIONS - CastleLine (Details) - USD ($) shares in Thousands, $ in Thousands	Jul. 17, 2015	Jun. 30, 2016	Dec. 31, 2015
Acquisitions
Goodwill		$ 81,406	$ 82,801
CastleLine
Acquisitions
Cash paid at acquisition	$ 12,300
Accounts payable	$ 10,500
Contingent consideration arrangements, payment period	4 years
Number of shares exchanged for acquisition (in thousands)	495
Value of common stock paid at acquisition	$ 14,400
Contingent consideration arrangements, range of outcomes, value, high	3,800
Cash		1,088
Accounts receivable, net		100
Prepaid expenses		20
Restricted cash		2,501
Non-compete agreements		1,130
Databases/other		1,800
Customer relationships		395
Trademarks and trade names		160
Deferred taxes		356
Goodwill		26,730
Total assets		34,280
Accounts payable and accrued expenses		(837)
Deferred revenue		0
Purchase price		33,443
CastleLine | Initial purchase price allocation
Acquisitions
Business combination, consideration transferred	33,400
Cash	1,088
Accounts receivable, net	510
Prepaid expenses	66
Restricted cash	2,501
Non-compete agreements	1,105
Databases/other	465
Customer relationships	395
Trademarks and trade names	150
Deferred taxes	0
Goodwill	28,125
Total assets	34,405
Accounts payable and accrued expenses	(875)
Deferred revenue	(87)
Purchase price	$ 33,443
CastleLine | Adjustments
Acquisitions
Cash		0
Accounts receivable, net		(410)
Prepaid expenses		(46)
Restricted cash		0
Non-compete agreements		25
Databases/other		1,335
Customer relationships		0
Trademarks and trade names		10
Deferred taxes		356
Goodwill		(1,395)
Total assets		(125)
Accounts payable and accrued expenses		38
Deferred revenue		87
Purchase price		$ 0