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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, employer contributions	$ 0.0	$ 0.0		$ 0.0	$ 0.0
Supplemental Executive Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, employer contributions	0.4	$ 0.4		0.8	$ 0.8
Obligations under the supplemental plan	$ 21.2			$ 21.2		$ 21.4
Supplemental Executive Retirement Plan | Scenario, Forecast
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, employer contributions			$ 0.8

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- Definition

Defined Benefit Plan Supplemental Plan Obligations

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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+ References

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