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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract] |  |  |
Defined contribution pension plans | $ 3.2 | $ 3.1 | $ 2.5
Equity Securities | United States |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Long-term return on plan assets | 9.00% |  |
Plan asset target allocation | 36.00% |  |
Fixed Income | United States |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Long-term return on plan assets | 4.00% |  |
Plan asset target allocation | 49.00% |  |
Funds | United States |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Defined benefit plan assets | 30.00% |  |
Multi-asset Strategies and CMRT | United States |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Long-term return on plan assets | 3.00% |  |
Defined Benefit Pension Plans |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Expected contributions to Defined Benefit Plans in Next Fiscal Year | $ 2.0 |  |
Actuarial losses expected to be recognized as a component of net period cost in next fiscal year | $ 1.5 |  |
Weighted-average rate determining the actuarial present value of benefit obligation | 2.90% | 3.90% |
Long-term return on plan assets | 4.70% | 7.20% | 6.90%
Defined Benefit Pension Plans | CMRT |  |  |
Compensation And Retirement Disclosure [Abstract] |  |  |
Long-term return on plan assets |  | 7.50% | 7.50%

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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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