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Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Current Assets: |  |
Allowance for doubtful accounts | $ 299 | $ 291
Allowance for inventory obsolescence | 19 | 19
Noncurrent Assets: |  |
Accumulated depreciation, rental equipment | 168,466 | 165,428
Accumulated depreciation, property and equipment | 11,665 | 11,556
Accumulated amortization, operating lease right of use assets | 36 |
Accumulated amortization, intangibles | $ 1,789 | $ 1,758
Stockholders’ Equity: |  |
Preferred stock, shares authorized (in shares) | 5,000,000 | 5,000,000
Preferred stock, shares issued (in shares) | 0 | 0
Preferred stock, shares outstanding (in shares) | 0 | 0
Common stock, par value (in USD per share) | $ 0.01 | $ 0.01
Common stock, shares authorized (in shares) | 30,000,000 | 30,000,000
Common stock, shares issued (in shares) | 13,133,000 | 13,005,000
Common stock, shares outstanding (in shares) | 13,133,000 | 13,005,000

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