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Concentration of Risk, Segment and Geographic Information - Additional Information 1 (Details) | 12 Months Ended
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Dec. 31, 2018 USD ($) Customer | Dec. 31, 2017 USD ($) Customer
Concentration Risk [Line Items] |  |
Cash equivalents | $ | $ 45,780,000 | $ 43,471,000
Customer Concentration Risk [Member] | Revenues [Member] |  |
Concentration Risk [Line Items] |  |
Number of major partners | Customer | 3 | 1
Customer Concentration Risk [Member] | Revenues [Member] | Partner 1 [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage (in hundredths) | 34.00% | 95.00%
Customer Concentration Risk [Member] | Revenues [Member] | Partner 2 [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage (in hundredths) | 25.00% |
Customer Concentration Risk [Member] | Revenues [Member] | Partner 3 [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage (in hundredths) | 14.00% |
Customer Concentration Risk [Member] | Accounts Receivable [Member] |  |
Concentration Risk [Line Items] |  |
Number of major partners | Customer | 2 | 1
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Partner 1 [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage (in hundredths) | 67.00% | 100.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Partner 2 [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage (in hundredths) | 28.00% |
Customer Concentration Risk [Member] | Money Market Funds [Member] |  |
Concentration Risk [Line Items] |  |
Cash equivalents | $ | $ 0 |

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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3044-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + 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 For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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- Definition Number of external partners that accounts for 10 percent or more of an entity's revenues during the period. + References No definition available. + Details
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