Income Taxes - Reconciliation of Gross Unrecognized Tax Benefits (Details) - Pension Plans $ in Millions	Dec. 31, 2018 USD ($)
Benefit payments
2019	$ 5.8
2020	6.4
2021	7.1
2022	6.1
2023	6.3
2024-2028	$ 35.9

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 715
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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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