Securities Held-to-Maturity - Schedule of Maturity Profile of Securities Held-to-Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Held-to-maturity due one year through five years	$ 2,000	$ 2,000
Held-to-maturity due five years through ten years	3,494	7,494
Held-to-maturity due over ten years	5,370	7,369
Held-to-maturity cost or amortized cost	$ 10,864	$ 16,863