Summary of Significant Accounting Policies - Additional Information (Details) shares in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2018 USD ($) shares	Dec. 31, 2018 USD ($) customer	Dec. 31, 2017 USD ($) customer
Significant Accounting Policies [Line Items]
Accounts receivable payment terms		30 days
Accounts receivable related to products and services		$ 15,095,000	$ 14,822,000
Goodwill and intangible asset impairment charge		0
Impairment charges of Long-lived assets disposition		0	0
Impairment charges of Long-lived assets held for use		0	0
Sales, general and administrative		72,509,000	69,959,000
Preferred stock convertible to common stock | shares	14.3
Recognition of beneficial conversion feature series B preferred stock	$ 13,500,000	13,488,000
Product Shipment
Significant Accounting Policies [Line Items]
Sales, general and administrative		$ 2,500,000	$ 2,300,000
Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives of property and equipment		3 years
Intangible assets, amortization period		1 year
Minimum | Acquired Technology, Customer Relationships, Manufacturing Know-how, Licensed Technology, Supply Agreements and Certain Trade Names and Trademarks
Significant Accounting Policies [Line Items]
Intangible assets, amortization period		1 year
Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives of property and equipment		7 years
Intangible assets, amortization period		20 years
Maximum | Acquired Technology, Customer Relationships, Manufacturing Know-how, Licensed Technology, Supply Agreements and Certain Trade Names and Trademarks
Significant Accounting Policies [Line Items]
Intangible assets, amortization period		20 years
Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk, number of customers | customer		0	0
Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk, number of customers | customer		0	0