Summary of Significant Accounting Policies - Schedule of Cash and Available-For-Sale Securities' Cost, Gross Unrealized Losses and Fair Value by Significant Investment Category (Detail) - USD ($) $ in Thousands |
Sep. 30, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Dec. 31, 2015 |
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Schedule of Available-for-sale Securities [Line Items] | ||||
Cost | $ 60,494 | |||
Gross Unrealized Losses | (62) | |||
Fair Value | 60,432 | |||
Cash and cash equivalents | 20,762 | $ 12,078 | $ 7,626 | $ 19,197 |
Marketable securities | 39,670 | |||
Cash [Member] | ||||
Schedule of Available-for-sale Securities [Line Items] | ||||
Cost | 13,711 | |||
Fair Value | 13,711 | |||
Cash and cash equivalents | 13,711 | |||
Level 1 [Member] | Money Market Funds [Member] | ||||
Schedule of Available-for-sale Securities [Line Items] | ||||
Cost | 3,057 | |||
Fair Value | 3,057 | |||
Cash and cash equivalents | 3,057 | |||
Level 2 [Member] | Corporate Securities [Member] | ||||
Schedule of Available-for-sale Securities [Line Items] | ||||
Cost | 43,726 | |||
Gross Unrealized Losses | (62) | |||
Fair Value | 43,664 | |||
Cash and cash equivalents | 3,994 | |||
Marketable securities | $ 39,670 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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