Fair Value Measurements - Additional Information (Detail) - USD ($) |
1 Months Ended | 3 Months Ended |
|---|---|---|
Jan. 31, 2017 |
Apr. 30, 2017 |
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| Fair Value Measurements Disclosure [Line Items] | ||
| Fair value measurements of our financial assets and liabilities | $ 12,970,000 | $ 12,974,000 |
| Goodwill impairment charge | 23,500,000 | 23,500,000 |
| Loss on impairment of long-lived assets held for sale | 300,000 | |
| Loss on impairment | 500,000 | |
| Other-than-temporary impairment | $ 0 | |
| Maximum maturity of marketable securities | Three months or less | |
| Cash equivalents and marketable securities | 38,700,000 | $ 37,100,000 |
| Fair Value, Inputs, Level 3 [Member] | ||
| Fair Value Measurements Disclosure [Line Items] | ||
| Fair value measurements of our financial assets and liabilities | $ 0 | $ 0 |
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- Definition Aggregate cash, cash equivalents, short term investments and restricted cash. No definition available.
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- Definition Cash Equivalents Maximum Maturity Period No definition available.
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- Definition Fair Value Measurements Disclosure [Line Items] No definition available.
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of asset after deduction of liability. No definition available.
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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