Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Stock based compensation awards, fair value of awards outstanding		$ 49,500		$ 49,500
Deferred compensation arrangements, liability, noncurrent		37,300		37,300
Stock compensation expense (benefit)	$ 1,921	580	$ 3,892	(5,484)
YP Acquisition
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Shares held in escrow (in shares)							1.8
Number of shares expected to be returned by the seller	0.7		0.7
Amount to be paid before allowance of tax credit	$ 8,000		$ 8,000
Indemnification Asset | Fair Value, Inputs, Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of indemnification asset	25,200		25,200		$ 24,300
Change in fair value	800		800
Indemnification Asset | Fair Value, Inputs, Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value of indemnification asset	$ 0	25,371	0	25,371	$ 0	$ 29,789
Change in fair value		$ (600)	$ 0	$ (4,418)