Income Taxes - Current and Deferred Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Current (benefit) expense	$ 1,241	$ (313)
Deferred expense	408	846
Income tax expense	$ 1,649	$ 533