Income Tax - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
Allowance for doubtful accounts	$ 271	$ 170
Unearned income	6,807	4,394
Investment in equity subsidiary	51	220
Share-based compensation	1,222	1,684
Debt issuance costs	249	309
Accrued liabilities	1,034	1,257
Derivative liability	1,220	351
Accrual of contract maintenance cost	134	157
Impairment of asset	289	289
Other	1,546	1,976
Total gross deferred tax assets	12,823	10,807
Deferred tax liabilities
Capitalized salaries	1,828	1,756
Derivative asset	0	185
Difference between the assigned values and the tax basis of assets and liabilities recognized in business combinations	12,568	16,240
Other	557	659
Total gross deferred tax liabilities	14,953	18,840
Deferred tax liability, net	$ (2,130)	$ (8,033)