Benefit Plans - Additional Information (Detail) - USD ($)		12 Months Ended
	Jan. 01, 2000	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Minimum eligibility for full-time employees, age		21 years
Number of highest-paid consecutive years for benefits		5 years
Employer contributions		$ 205,000	$ 1,800,000
Amount of accumulated benefit obligation for the defined benefit pension plan		$ 0	5,300,000
Percentage of first employee compensation for which company makes matching contribution		1.00%
Company contribution on employee specific contribution		50.00%
Number of hours in service required for the contribution to be allocated		1000 hours
Minimum eligibility for employees under 401(k) Plan age		19 years
Number of plan service years after which employer matching contribution vest		2 years
Expense attributable to the Plan amounted		$ 770,000	740,000
Percentage of vested participants	100.00%
Participants years of credited service	2 years
Compensation expense for ESOP		$ 0	$ 0
Shares of the Company held by the ESOP (in shares)		0	230,846
Minimum
Defined Benefit Plan Disclosure [Line Items]
Period of service credit by employee		1 year
Percentage of employee for which company makes specified contribution		2.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee for which company makes specified contribution		6.00%