Segment Information - Net Sales by Offering for North America, EMEA and APAC (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue from External Customer [Line Items]
Revenues from external customers	$ 2,144,051	$ 1,685,466
North America Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	1,674,381	1,242,441
EMEA Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	418,886	390,175
APAC Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	50,784	52,850
Hardware Net Sales [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	1,311,201	926,380
Hardware Net Sales [Member] | North America Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	1,128,486	748,337
Hardware Net Sales [Member] | EMEA Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	174,969	171,525
Hardware Net Sales [Member] | APAC Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	7,746	6,518
Software Net Sales [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	537,115	540,292
Software Net Sales [Member] | North America Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	305,163	322,079
Software Net Sales [Member] | EMEA Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	201,082	183,148
Software Net Sales [Member] | APAC Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	30,870	35,065
Services Net Sales [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	295,735	218,794
Services Net Sales [Member] | North America Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	240,732	172,025
Services Net Sales [Member] | EMEA Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	42,835	35,502
Services Net Sales [Member] | APAC Segment [Member]
Revenue from External Customer [Line Items]
Revenues from external customers	$ 12,168	$ 11,267