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Income Taxes - Additional Information (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Income Taxes [Line Items] |  |  |
United States statutory tax rate | 35.00% | 35.00% | 35.00%
Cash and cash equivalents held by foreign subsidiaries | $ 6,500,000 |  |
Temporary difference related to undistributed earnings | 13,000,000 | $ 14,400,000 |
Valuation allowance against net deferred tax assets | 7,715,000 |  |
Canada |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss, carryforwards | $ 13,600,000 |  |
Net operating loss, carryforwards expiration year | 2033 |  |
Valuation allowance against net deferred tax assets | $ 3,700,000 |  |
Russia |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss, carryforwards | $ 572,000 |  |
Net operating loss, carryforwards expiration year | 2026 |  |
United Kingdom |  |  |
Income Taxes [Line Items] |  |  |
Net operating loss, carryforwards | $ 48,500 |  |
U. S. |  |  |
Income Taxes [Line Items] |  |  |
Valuation allowance against net deferred tax assets | $ 4,000,000 |  |

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