PROPERTY AND EQUIPMENT - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Depreciation and amortization of property and equipment	$ 8,486	$ 7,970	$ 11,961

The aggregate expense recognized in the current period that allocates the cost of tangible assets to periods that benefit from use of the assets.

No definition available.

Name:	sons_DepreciationAndAmortizationOfTangibleAssets
Namespace Prefix:	sons_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration