Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1,265	$ 982
Accumulated depreciation	$ 3,168	$ 2,696
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock authorized (shares)	250,000,000	250,000,000
Common stock issued (shares)	58,359,108	56,956,935
Common stock outstanding (shares)	45,810,769	44,392,695
Treasury stock, shares (shares)	12,564,240	12,564,240

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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