Employee Benefit Plans - Summary of Pension Plan's Assets By Asset Type (Detail) - Defined Benefit Pension Plan - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Plan Assets Category [Line Items]
Fair value of plan assets	$ 1,296	$ 1,116	$ 2,465
Fair value of plan assets allocation, percentage	100.00%	100.00%
Mutual Funds - Equity
Defined Benefit Plan Plan Assets Category [Line Items]
Fair value of plan assets	$ 794	$ 658
Fair value of plan assets allocation, percentage	61.00%	59.00%
Mutual Funds - Fixed Income
Defined Benefit Plan Plan Assets Category [Line Items]
Fair value of plan assets	$ 500	$ 458
Fair value of plan assets allocation, percentage	39.00%	41.00%
Cash and Cash Equivalents
Defined Benefit Plan Plan Assets Category [Line Items]
Fair value of plan assets	$ 2
Fair value of plan assets allocation, percentage	0.00%	0.00%