Organization and Summary of Significant Accounting Policies - Summary of Changes in Estimated Product Warranty Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Standard and Extended Product Warranty
Balance, January 1	$ 780	$ 314	$ 675
Utilization of reserve	(245)	(155)	(299)
Warranty expense (recoveries)	109	621	(62)
Balance, December 31	$ 644	$ 780	$ 314

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

+ References

+ Details

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