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Significant Accounting Policies - Additional Information (Detail) | 3 Months Ended
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Mar. 31, 2017 USD ($) Segment
Accounting Policy [Line Items] |
Number of operating segment | Segment | 1
ASU 2016-09 [Member] |
Accounting Policy [Line Items] |
Retrospective increase in deferred tax assets for previously unrecognized excess tax benefits | $ 19,500,000
Increase in valuation allowance | 19,500,000
Net impact to accumulated deficit | $ 0

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- Definition Accounting policy. + References No definition available. + Details
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- Definition Amount of the related income tax effect of a cumulative effect on retained earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794 + Details
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- Definition Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements. + References No definition available. + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=75116654&loc=d3e32123-109318 + Details
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- Details
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