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Commitments and Contingencies - Narrative (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Loss Contingencies [Line Items] |  |  |
Rent expense for operating leases | $ 2,000,000.0 | $ 1,800,000 | $ 1,500,000
Minimum monthly purchase amount | 40,000 |  |
Minimum annual purchase amount | $ 6,600,000 |  |
Purchase commitment term | 3 years |  |
Purchase commitment renewal term | 3 years |  |
shareholder derivative claim [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Litigation Settlement, Amount | $ 250,000 |  |
Securities Class Action [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Litigation Settlement, Amount | $ 1,750,000 |  |

X
- Definition Represents the monthly purchase minimum the Company is required to purchase until the termination date. + References No definition available. + Details
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X
- Definition Period of time that a purchase commitment agreement is automatically renewed for after the original term ends unless notice of termination is given by either party to the agreement. + References No definition available. + Details
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- Definition Period of time that a purchase commitment agreement is in effect. + References No definition available. + Details
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X
- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Definition Amount of judgment or settlement awarded to (against) the entity in respect of litigation. + References No definition available. + Details
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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. + References No definition available. + Details
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- Definition Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(19)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(17)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(25)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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