REVENUE - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of revenue
Net sales	$ 652,752	$ 729,410	$ 1,914,603	$ 2,103,407
Notebooks/Mobility
Disaggregation of revenue
Net sales	202,548	219,655	595,133	606,485
Desktops
Disaggregation of revenue
Net sales	63,409	92,126	192,005	258,518
Software
Disaggregation of revenue
Net sales	77,095	78,523	204,444	246,142
Servers/Storage
Disaggregation of revenue
Net sales	56,333	59,302	164,785	179,137
Net/Com Products
Disaggregation of revenue
Net sales	62,501	52,561	159,762	150,590
Displays and Sound
Disaggregation of revenue
Net sales	54,976	70,534	161,374	189,073
Accessories
Disaggregation of revenue
Net sales	83,235	87,397	275,820	269,749
Other Hardware/Services
Disaggregation of revenue
Net sales	52,655	69,312	161,280	203,713
Business Solutions
Disaggregation of revenue
Net sales	230,985	273,756	700,859	797,740
Business Solutions | Notebooks/Mobility
Disaggregation of revenue
Net sales	72,694	79,287	226,959	240,644
Business Solutions | Desktops
Disaggregation of revenue
Net sales	20,097	34,806	67,891	96,377
Business Solutions | Software
Disaggregation of revenue
Net sales	33,061	36,879	93,710	110,826
Business Solutions | Servers/Storage
Disaggregation of revenue
Net sales	20,209	26,352	69,685	81,452
Business Solutions | Net/Com Products
Disaggregation of revenue
Net sales	19,140	25,200	54,916	70,806
Business Solutions | Displays and Sound
Disaggregation of revenue
Net sales	21,161	23,224	64,338	64,422
Business Solutions | Accessories
Disaggregation of revenue
Net sales	27,855	26,306	75,362	72,036
Business Solutions | Other Hardware/Services
Disaggregation of revenue
Net sales	16,768	21,702	47,998	61,177
Enterprise Solutions
Disaggregation of revenue
Net sales	259,767	278,295	839,943	871,969
Enterprise Solutions | Notebooks/Mobility
Disaggregation of revenue
Net sales	63,093	77,214	222,139	240,621
Enterprise Solutions | Desktops
Disaggregation of revenue
Net sales	33,451	36,821	94,674	112,067
Enterprise Solutions | Software
Disaggregation of revenue
Net sales	26,336	28,439	77,394	91,954
Enterprise Solutions | Servers/Storage
Disaggregation of revenue
Net sales	23,832	16,374	63,042	48,536
Enterprise Solutions | Net/Com Products
Disaggregation of revenue
Net sales	27,941	11,666	72,172	38,866
Enterprise Solutions | Displays and Sound
Disaggregation of revenue
Net sales	16,511	29,641	58,603	82,812
Enterprise Solutions | Accessories
Disaggregation of revenue
Net sales	40,538	46,546	164,185	162,601
Enterprise Solutions | Other Hardware/Services
Disaggregation of revenue
Net sales	28,065	31,594	87,734	94,512
Public Sector Solutions
Disaggregation of revenue
Net sales	162,000	177,359	373,801	433,698
Public Sector Solutions | Notebooks/Mobility
Disaggregation of revenue
Net sales	66,761	63,154	146,035	125,220
Public Sector Solutions | Desktops
Disaggregation of revenue
Net sales	9,861	20,499	29,440	50,074
Public Sector Solutions | Software
Disaggregation of revenue
Net sales	17,698	13,205	33,340	43,362
Public Sector Solutions | Servers/Storage
Disaggregation of revenue
Net sales	12,292	16,576	32,058	49,149
Public Sector Solutions | Net/Com Products
Disaggregation of revenue
Net sales	15,420	15,695	32,674	40,918
Public Sector Solutions | Displays and Sound
Disaggregation of revenue
Net sales	17,304	17,669	38,433	41,839
Public Sector Solutions | Accessories
Disaggregation of revenue
Net sales	14,842	14,545	36,273	35,112
Public Sector Solutions | Other Hardware/Services
Disaggregation of revenue
Net sales	$ 7,822	$ 16,016	$ 25,548	$ 48,024