Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Allowance for doubtful accounts, current	$ 38,630	$ 11,985
Accumulated amortization of other intangible assets	16,175	12,853
Allowance for doubtful accounts, noncurrent	$ 10,000	$ 0
STOCKHOLDERS’ EQUITY:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	100,000,000	100,000,000
Common stock issued (in shares)	75,256,000	74,960,000
Common stock outstanding (in shares)	73,788,000	73,436,000
Common stock in treasury (in shares)	1,468,000	1,524,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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