Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Trade receivables, allowances	$ 1,062	$ 945
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, authorized	50,000,000	50,000,000
Preferred stock, outstanding	0	0
Preferred stock, shares Issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized	300,000,000	300,000,000
Common stock, issued	44,075,840	43,747,805
Treasury stock, shares	5,367,000	5,167,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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