Organization and Summary of Significant Accounting Policies - Additional Information (Detail)		12 Months Ended			48 Months Ended
	May 24, 2018 tranche shares	Dec. 31, 2018 USD ($) source depository_institution segment shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2011 shares	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)
Summary Of Significant Accounting Policy [Line Items]
Impairment losses		$ 2,000,000	$ 1,000,000	$ 0
Number of revenue sources | source		2
Cost of sales		$ 161,485,000	136,710,000	97,709,000
Warranty period		1 year
Research and development costs		$ 76,856,000	55,373,000	$ 30,609,000
Allowance for doubtful accounts		$ (1,882,000)	(754,000)
Number of depository institutions | depository_institution		4
Aggregate balances in depository institution accounts		$ 342,300,000
Cash surrender value of corporate-owned life insurance policies		$ 3,596,000	$ 3,846,000
Number of reportable segments of company | segment		2
New option granted (in shares) | shares		0	0	0
Retained earnings		$ 171,383,000	$ 123,185,000				$ 142,179,000
Cumulative effect of applying a change in accounting principle		18,993,000	178,000
Advertising
Summary Of Significant Accounting Policy [Line Items]
Cost of sales		1,100,000	500,000	$ 400,000
Additional Paid-in Capital
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle			475,000
Retained Earnings
Summary Of Significant Accounting Policy [Line Items]
Cumulative effect of applying a change in accounting principle		18,993,000	$ (297,000)
Impact of Adoption of Topic 606 on Opening Balance Sheet | Accounting Standards Update 2014-09
Summary Of Significant Accounting Policy [Line Items]
Retained earnings		$ 19,000,000					$ 18,994,000
Performance Shares
Summary Of Significant Accounting Policy [Line Items]
New option granted (in shares) | shares	6,365,856				1,000,000
Chief Executive Officer
Summary Of Significant Accounting Policy [Line Items]
Number of vesting tranches of share-based awards | tranche	12
Subsequent Event | Restatement Adjustment | Accounting Standards Update 2016-02
Summary Of Significant Accounting Policy [Line Items]
Operating Lease, Right-of-Use Asset						$ 11,000,000
Operating Lease, Liability						$ 12,000,000