Goodwill - Summary of Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 6,968
Foreign currency translation adjustment	(8,256)
Goodwill, Ending balance	357,869
ADVA Optical Networking SE, [Member]
Goodwill [Line Items]
Goodwill from Business Combination with ADVA	359,157
Goodwill, Ending balance	359,200
Network Solutions [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	6,568
Foreign currency translation adjustment	(6,220)
Goodwill, Ending balance	270,916
Network Solutions [Member] | ADVA Optical Networking SE, [Member]
Goodwill [Line Items]
Goodwill from Business Combination with ADVA	270,568
Services & Support [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	400
Foreign currency translation adjustment	(2,036)
Goodwill, Ending balance	86,953
Services & Support [Member] | ADVA Optical Networking SE, [Member]
Goodwill [Line Items]
Goodwill from Business Combination with ADVA	$ 88,589