Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ References

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- References

No definition available.

+ Details

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Pension and Other Postretirement Benefits - Schedule of Funded Status of the Plans (Detail) £ in Thousands, $ in Thousands	Dec. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 GBP (£)	Dec. 31, 2017 USD ($)
Foreign Pension Benefits [Member]
Funded status of the plans:
Fair value of plan assets	$ 57,900	£ 43,913	$ 49,651	£ 38,991
Defined Benefit Pension Plan [Member] \| U.S. [Member]
Funded status of the plans:
Fair value of plan assets	195,667		182,541		$ 199,138
Less benefit obligations	261,902		233,790		254,976
Funded status at December 31	(66,235)		(51,249)
Defined Benefit Pension Plan [Member] \| Foreign Pension Benefits [Member]
Funded status of the plans:
Fair value of plan assets	57,900		49,651		56,419
Less benefit obligations	62,339		54,337		64,613
Funded status at December 31	(4,439)		(4,686)
Other Postretirement Benefit Plans [Member]
Funded status of the plans:
Fair value of plan assets	0		0		0
Less benefit obligations	11,398		15,810		$ 16,979
Funded status at December 31	$ (11,398)		$ (15,810)