Retirement Plans - Actuarial Assumptions (Details) - Pension Plan	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
United States
Defined Benefit Plan Disclosure
Discount rate	4.00%	3.40%
Expected rate of return on plan assets	5.90%	5.90%
United Kingdom
Defined Benefit Plan Disclosure
Discount rate	2.00%	2.80%
Expected rate of return on plan assets	3.30%	3.80%

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

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)(1)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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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=108410482&loc=d3e1928-114920

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- Definition

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+ References

No definition available.

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