LEASES - Balance Sheet Classification (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jan. 01, 2019
Assets [Abstract]
Operating lease assets	$ 371,289
Finance lease assets	1,167
Total leased assets	372,456	$ 384,187
Liabilities, Current [Abstract]
Current portion of operating lease liabilities	23,011
Finance lease, current	334
Liabilities, Noncurrent [Abstract]
Operating lease liabilities, less current portion	356,062
Finance lease, noncurrent	575
Total lease liabilities	379,982	$ 389,403
Accumulated amortization of finance leases	$ 1,421