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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Operating Loss Carryforwards [Line Items] |  |  |
Deferred tax assets, valuation allowance | $ 700,000 | $ 0 |
Excess tax shortfall (benefit) from exercise of stock options | 1,100,000 | 300,000 | $ (1,800,000)
Undistributed earnings of foreign subsidiaries | $ 1,900,000 | 1,900,000 |
Likelihood percentage of being realized upon ultimate settlement with the relevant tax authority | 50.00% |  |
Unrecognized tax benefits | $ 0 | 0 |
Changes in unrecognized benefits | 0 | $ 0 | $ 0
TRS-RenTelco [Member] | Bangalore, India [Member] |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Deferred tax assets, valuation allowance | $ 700,000 |  |

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