ACQUISITIONS (ASSETS ACQUIRED TABLE) (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017	Nov. 08, 2017	Apr. 03, 2017
Business Acquisition [Line Items]
Total deferred tax assets, net	$ 16,500,000
Goodwill	205,632,000	$ 206,694,000
Accrued employee compensation and benefits	85,004,000	$ 83,997,000
BH
Business Acquisition [Line Items]
Total purchase price	$ 1
Motif [Member]
Business Acquisition [Line Items]
Cash			$ 5,997,000
Accounts receivable.			5,187,000
Prepaid Expenses			1,248,000
Other assets			670,000
Property, plant and equipment.			2,182,000
Income Taxes Receivable			1,691,000
Goodwill			39,272,000
Total assets acquired			93,447,000
Accounts payable			2,914,000
Accrued employee compensation and benefits			5,249,000
Accrued expenses			104,000
Deferred tax liabilities			11,402,000
Other			340,000
Total liabilities assumed			20,009,000
Total purchase price			73,438,000
Motif [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets			$ 37,200,000
Connextions
Business Acquisition [Line Items]
Accounts receivable.				$ 15,959,000
Prepaid Expenses				241,000
Other assets				51,000
Property, plant and equipment.				7,594,000
Goodwill				35,272,000
Total assets acquired				94,117,000
Accounts payable				1,000
Accrued employee compensation and benefits				346,000
Accrued expenses				386,000
Deferred tax liabilities				15,273,000
Deferred revenue.				399,000
Total liabilities assumed				16,405,000
Total purchase price				77,712,000
Connextions | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets				$ 35,000,000