Number of customers.

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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.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Concentrations of Credit Risk, Accounts Receivable and Related Valuation Accounts - Additional Information (Detail)	1 Months Ended	9 Months Ended		12 Months Ended
	May 31, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) Customer
Accounts Notes And Loans Receivable [Line Items]
Adjustment to account receivable		$ (40,000)	$ 11,000
Accounts receivable		$ 0		$ 40,000
Accounts Receivable \| Credit Concentration Risk \| Four Health Care Providers
Accounts Notes And Loans Receivable [Line Items]
Number of customers \| Customer				4
Concentration risk percentage				100.00%
Sales Arrangement
Accounts Notes And Loans Receivable [Line Items]
Sales arrangement entered	$ 517,000
Adjustment to account receivable				$ 559,000
Sales Arrangement \| Foreign Currency
Accounts Notes And Loans Receivable [Line Items]
Adjustment to account receivable				$ 40,000