SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Other Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets	$ 508,370	$ 551,426
Total other intangible assets	540,370	583,426
Distribution relationships
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets	340,056	366,423
Trade names
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets	65,207	71,918
Technology
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets	70,913	85,454
Other
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets	32,194	27,631
Insurance licenses
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	$ 32,000	$ 32,000
Minimum | Software
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	3 years
Minimum | Distribution relationships
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	14 years
Minimum | Trade names
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	13 years
Minimum | Technology
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	7 years
Maximum | Software
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	5 years
Maximum | Distribution relationships
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	22 years
Maximum | Trade names
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	17 years
Maximum | Technology
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets, estimated useful life	14 years