Commitments and Contingencies - PP&E Capital Leases and Rental Expense (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases
Rent expense for pole rental	$ 9.1	$ 8.5	$ 7.3
Franchise fees and other franchise related costs	$ 22.8	$ 24.3	$ 24.8

Amount of franchise fees and other franchise-related costs under franchise agreements included in costs of operations.

No definition available.

Name:	wow_FranchiseFeesAndOtherFranchiseRelatedCosts
Namespace Prefix:	wow_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration