Defined benefit and 401(k) savings plan, Weighted Average Assumptions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019
Plan [Member]
Weighted Average Assumptions Used to Calculate Projected Benefit Obligation [Abstract]
Total contributions expected		$ 1.0
Pension Benefits [Member]
Weighted Average Assumptions Used to Calculate Projected Benefit Obligation [Abstract]
Discount rate	0.90%
Expected rate of return	3.00%
Rate of future compensation increases	1.50%

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 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

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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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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- References

No definition available.

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