LEASES - Condensed Consolidated balance sheet information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019
Balance sheet information related to leases
Operating lease right-of-use assets	$ 103,676	$ 103,378
Operating lease right-of-use assets (Classification)	Us-gaap:OperatingLeaseRightOfUseAsset
Finance lease right-of-use assets	$ 541
Finance lease right-of-use assets (Classification)	Us-gaap:OtherAssets
Total lease assets	$ 104,217
Operating	$ 33,675	33,393
Operating (Classification)	Us-gaap:OperatingLeaseLiabilityCurrent
Finance (Classification)	Us-gaap:FinanceLeaseLiabilityCurrent
Operating	$ 83,693	$ 83,662
Operating (Classification)	Us-gaap:OperatingLeaseLiabilityNoncurrent
Finance (Classification)	Us-gaap:FinanceLeaseLiabilityNoncurrent
Total lease liabilities	$ 117,935