Other Current and Long-Term Assets (Schedule Of Other Long-term Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other Assets, Noncurrent [Abstract]
Customer acquisition costs	$ 107,345	$ 104,369
Contract assets, net	95,962	91,681
Deferred income taxes	28,340	31,549
Deferred sales commissions	11,968	11,719
Investment in long-term product supply arrangements	11,185	12,065
Taxes receivable	6,329	6,329
Other assets	34,375	31,883
Other long-term assets	$ 295,504	$ 289,595

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as noncurrent.

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Carrying amount as of the balance sheet date of amounts paid in advance which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

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