CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounts receivable, allowance for uncollectible accounts	$ 2,864	$ 2,714
Debt issuance costs	$ 3,858	$ 5,834
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	19,376,773	21,153,878
Common stock, shares outstanding	19,376,773	21,153,878
Treasury stock, shares	3,112,840	3,660,201

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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