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Pension Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract]
Interest cost	$ 4	$ 5	$ 4
Expected return on plan assets	(5)	(6)	(5)
Amortization of net loss	3	2	1
Net periodic benefit cost	$ 2	$ 1	$ 0

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Defined benefit plan expected amortization of gain loss.

+ References

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

+ References

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-Publisher FASB
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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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