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Description of Business and Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands		12 Months Ended
	Aug. 26, 2020	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)
Asset Impairment Charges [Abstract]
Reverse stock split, conversion ratio	0.5555
Deferred contract costs, current		$ 9,100	$ 10,500	$ 10,300
Deferred contract costs, noncurrent		2,800	3,100	3,500
Amortization of deferred contract costs		13,600	14,100	9,900
Advertising Expense		$ 7,200	$ 5,500	23,400
Common stock, shares issued (in shares) \| shares		59,590,422	57,443,282
Common stock, shares outstanding (in shares) \| shares		32,912,012	33,490,526
Treasury stock (in shares) \| shares		26,678,410	23,952,756
Deferred compensation arrangement, requisite service period		3 years
Operating lease, liability, noncurrent		$ 24,552	$ 28,783
Operating lease, right-of-use asset		$ 9,202	39,046
Minimum \| Stock Options
Asset Impairment Charges [Abstract]
Requisite service period, options		3 years
Maximum \| Stock Options
Asset Impairment Charges [Abstract]
Requisite service period, options		4 years
Impact of Adoption
Asset Impairment Charges [Abstract]
Operating lease, liability, noncurrent				50,800
Operating lease, right-of-use asset				43,800
PYP
Asset Impairment Charges [Abstract]
Deferred contract costs, current		$ 2,700	4,800
Amortization of deferred contract costs		$ 4,800	$ 6,600	$ 8,400
Revenue Benchmark \| Customer Concentration Risk \| Local SMBs
Asset Impairment Charges [Abstract]
Concentration risk, percentage		89.00%
Revenue Benchmark \| Customer Concentration Risk \| Regional and National Large Businesses
Asset Impairment Charges [Abstract]
Concentration risk, percentage		11.00%
Revenue Benchmark \| Customer Concentration Risk \| Top Ten Directories
Asset Impairment Charges [Abstract]
Concentration risk, percentage		2.00%