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INCOME TAXES - ADDITIONAL INFORMATION (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Deferred Income Tax Expense (Benefit)			$ 900
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount		$ 3,700	3,400
Amortization of intangible assets	$ 540,520	159,573
Deferred Tax Assets, Tax Deferred Expense, Other	8,200
Deferred Tax Assets, Operating Loss Carryforwards	36,923	10,486
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	55,637	1,247
Deferred Tax Assets, Valuation Allowance	60,629	5,854
Unrecognized Tax Benefits	68,075	54	1,293	$ 4,348
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	29,100	100	1,300
Decrease in Unrecognized Tax Benefits is Reasonably Possible	3,600
Interest related to uncertain tax positions	300	800	$ 200
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	5,500	100
Undistributed Earnings of Foreign Subsidiaries	1,835,000
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	75,000
Unrecognized Tax Benefits, Income Tax Penalties Accrued	1,500
General Business Tax Credit Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Valuation Allowance	30,100	1,200
Anixter International [Member]
Operating Loss Carryforwards [Line Items]
Amortization of intangible assets	347,300
Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Taxes Payable	63,300	36,800
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	34,500	7,900
Operating Loss Carryforwards, Valuation Allowance	22,300	4,600
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	55,600	1,200
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards	2,400	$ 2,600
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 4,200