Other Balance Sheet Items (Prepaid Expenses And Other Current Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Prepaid registry fees, current	$ 22,654	$ 21,717
Prepaid expenses	17,920	19,818
Contingent Consideration receivable, Asset, Current	0	14,721
Accounts Receivable, after Allowance for Credit Loss, Current	4,642	1,524
Income Taxes Receivable	3,572	1,111
Other	2,245	1,639
Other current assets	$ 51,033	$ 60,530

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Amount of current assets classified as other.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Prepaid registry fees

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