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- Definition

Significant accounting policies.

+ References

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- Definition

Amounts 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.

+ References

Reference 1: 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(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3574-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant Accounting Policies [Line Items]
Decrease in cash flows from financing activities by adoption of accounting pronouncements		$ (35,400)	$ (948)
Reduction to research and development expenses		100	100
Accounts receivable		24	$ 31
ISU Abxis
Significant Accounting Policies [Line Items]
Accounts receivable		$ 20
Software
Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Computer equipment
Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Laboratory and office equipment \| Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Laboratory and office equipment \| Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives		7 years
Furniture \| Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Furniture \| Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives		7 years
Leasehold improvements \| Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Leasehold improvements \| Maximum
Significant Accounting Policies [Line Items]
Estimated useful lives		7 years
Scenario Forecast \| ASU 2016-18
Significant Accounting Policies [Line Items]
Decrease in cash flows from financing activities by adoption of accounting pronouncements	$ 14,300