COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands	Apr. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Contingent Consideration
Contingent acquisition liability		$ 4,778	$ 4,019	$ 4,756	$ 4,825
Salvaggio Teal And Associates
Contingent Consideration
Amount paid for contingent consideration	$ 1,700
Salvaggio Teal And Associates | Accrued expenses
Contingent Consideration
Contingent consideration classified as current		1,700
CCI Consulting Private Limited
Contingent Consideration
Contingent acquisition liability		1,300
Amount paid for contingent consideration	700
CCI Consulting Private Limited | Accrued expenses
Contingent Consideration
Contingent consideration classified as current		700
Saugatuck Technology Inc.
Contingent Consideration
Contingent acquisition liability		900
Amount paid for contingent consideration	$ 200
Saugatuck Technology Inc. | Other liabilities
Contingent Consideration
Contingent consideration classified as noncurrent		900
Experton Group AG | Other liabilities
Contingent Consideration
Contingent consideration classified as noncurrent		$ 900