Revenue Recognition - Balance Sheet Impact (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue
Prepaid expenses and other current assets	$ 26,840	$ 34,000
Accrued income taxes	30,333	5,062
Deferred revenue and customer deposits	14,432	9,845	$ 9,420
Retained earnings	753,268	$ 646,214
As previously reported
Revenue
Retained earnings	$ 1,105,714

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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