LEASES - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets
Operating lease right-of-use assets	$ 199,048	$ 203,834
Finance lease assets	36,007	41,647
Total leased assets	235,055	245,481
Current
Operating	71,992	73,422
Finance	11,256	14,543
Noncurrent
Operating	134,784	137,384
Finance	32,446	32,909
Total lease liabilities	$ 250,478	$ 258,258