Revenue - Disaggregate of Revenue by Reportable Segment and Revenue Category (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation Of Revenue [Line Items]
Revenue	$ 1,149,100	$ 1,025,536	$ 563,004
Subscriber Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	297,708	390,454	206,210
Access & Aggregation Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	358,418	374,002	356,794
Optical Networking Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	492,974	261,080	0
Network Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	974,389	916,793	498,834
Network Solutions [Member] | Subscriber Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	263,192	364,238	189,825
Network Solutions [Member] | Access & Aggregation Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	304,074	326,934	309,009
Network Solutions [Member] | Optical Networking Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	407,123	225,621	0
Services & Support [Member]
Disaggregation Of Revenue [Line Items]
Revenue	174,711	108,743	64,170
Services & Support [Member] | Subscriber Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	34,516	26,216	16,385
Services & Support [Member] | Access & Aggregation Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	54,344	47,068	47,785
Services & Support [Member] | Optical Networking Solutions [Member]
Disaggregation Of Revenue [Line Items]
Revenue	$ 85,851	$ 35,459	$ 0