ACQUISITIONS (Preliminary Consideration Paid) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Oct. 16, 2014	Sep. 19, 2014	Dec. 03, 2013	Sep. 04, 2013
Central Desktop
Business Acquisition [Line Items]
Negotiated sales price	$ 25,000
Working capital and other adjustments	76
Purchase price	25,076
TalkPoint
Business Acquisition [Line Items]
Negotiated sales price		56,500
Working capital and other adjustments		(917)
Purchase price		55,583
Powwownow
Business Acquisition [Line Items]
Negotiated sales price			53,183
Working capital and other adjustments			(684)
Purchase price			52,499
ACT
Business Acquisition [Line Items]
Negotiated sales price				53,000
Working capital and other adjustments				(1,515)
Purchase price				$ 51,485