Income Taxes - Significant Components of the Company's Net Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 33	$ 166
Contract liabilities		187
Accruals and allowances	1,253	972
Stock-based compensation	1,286	815
Deferred rent expense	1,267	1,327
Other	4	4
Gross deferred tax assets	3,843	3,471
Less valuation allowance	(33)	(352)
Total deferred tax assets	3,810	3,119
Deferred tax liabilities:
Intangible asset amortization	(2,603)	(2,036)
Depreciation	(1,814)	(1,823)
Total deferred tax liabilities	(4,417)	(3,859)
Net deferred tax liabilities	(607)	(740)
As reported:
Non-current deferred tax assets	55	98
Non-current deferred tax liabilities	$ (662)	$ (838)