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PROPERTY, PLANT AND EQUIPMENT, INTANGIBLE ASSETS AND GOODWILL - Narrative (Detail) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 10, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets in International outdoor segment		$ 2,417,830,000		$ 2,417,830,000		$ 2,451,813,000
Total amortization expense related to definite-lived intangible assets		24,200,000	$ 49,500,000	116,400,000	$ 148,200,000
Goodwill impairment		0		0		1,591,000
International Outdoor
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets in International outdoor segment		0		$ 0
Goodwill impairment			1,600,000		1,600,000	1,591,000
iHM
Indefinite-lived Intangible Assets [Line Items]
Impairment of indefinite lived intangible assets		33,100,000	$ 6,000,000		$ 6,000,000
Goodwill impairment						0
Americas Outdoor
Indefinite-lived Intangible Assets [Line Items]
Impairment of indefinite lived intangible assets		$ 7,800,000
Goodwill impairment						$ 0
Stuff Media LLC \| Subsequent Event
Indefinite-lived Intangible Assets [Line Items]
Purchase price of acquired company	$ 55,000,000