Other Balance Sheet Items (Prepaid Expenses And Other Current Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Prepaid registry fees, current	$ 21,717	$ 20,696
Prepaid expenses	19,818	14,109
Contingent Consideration receivable, Asset, Current	14,721	0
Accounts Receivable, after Allowance for Credit Loss, Current	1,524	6,029
Income Taxes Receivable	1,111	4,451
Other	1,639	2,080
Other current assets	$ 60,530	$ 47,365

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 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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