Pensions - Narrative (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2020 USD ($) plan participant	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Type [Extensible List]		Pension Plan
Number of plans | plan	2
Annuity purchase	$ 17,800	$ 17,831	$ 0
Settlement loss (gain)		819	693	$ (204)
Accumulated benefit obligations		636,500	644,000
Plan contributions		44,908	$ 30,369
Net actuarial losses		$ 44,300
Expected return on plan assets, net of administrative expenses		3.73%	3.68%	3.58%
Savings plan expense		$ 3,000	$ 10,800	$ 12,600
Consolidated Pension Plan of Dex Media
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets, net of administrative expenses		2.61%
Actual return on plan assets		7.40%	9.80%
YP Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets, net of administrative expenses		3.04%
Actual return on plan assets		11.10%	18.20%
Weighted Average
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets, net of administrative expenses		2.69%
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, number of participants | participant	500
Qualified Plan | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan contributions		$ 43,900	$ 29,600	2,900
Expected future employer contribution, next fiscal year		25,000
Nonqualified Plan | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan contributions		1,000	$ 700	$ 1,000
Expected future employer contribution, next fiscal year		$ 1,400