Redeemable Non-controlling Interest - Summary of Redeemable Non-controlling Interest Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Redeemable Noncontrolling Interest [Line Items]
Balance at beginning of period	$ 443,327
Reclassification of non-controlling interests		$ 443,757
Non-controlling interests in adtran holdings related to stock options exercised		1,175
Redemption of redeemable non-controlling interests	(20,384)	(1,657)
Net income attributable to redeemable non-controlling interests	9,824	10,092
Annual recurring compensation earned	(9,824)	(10,092)
Balance at end of period	$ 422,943	443,327
Adtran Networks [Member]
Redeemable Noncontrolling Interest [Line Items]
Stock option exercises		$ 52