ACQUISITIONS - Allocation of Purchase Consideration (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 02, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill	$ 1,487,187		$ 1,291,760	$ 1,258,922
Prime Distribution
Business Acquisition [Line Items]
Current assets		$ 8,879
Property and equipment		7,356
Right-of-use lease assets		35,017
Other intangible assets		55,000
Goodwill		176,484
Total assets		282,736
Current liabilities		12,243
Lease liabilities		35,017
Deferred tax liabilities		12,758
Net assets acquired		$ 222,718