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Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Pension benefits |  |  |
Net periodic benefit cost: |  |  |
Service cost | $ 1.6 | $ 1.5 | $ 1.4
Interest cost | 6.2 | 7.1 | 9.2
Expected return on plan assets | (11.9) | (11.7) | (12.0)
Amortization of prior service credit | 0.1 | 0.1 | 0.1
Amortization of actuarial loss (gain) | 1.8 | 2.0 | 2.1
Settlement loss | 1.8 | 3.7 | 3.5
Net periodic benefit cost | (0.4) | 2.7 | 4.3
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (6.3) | 1.8 | 1.5
Prior service credit arising during period | (2.0) | 0.0 | 0.0
Amortization of prior service credit | (0.1) | (0.1) | (0.1)
Amortization of actuarial (loss) gain | (1.8) | (2.0) | (2.1)
Settlement loss | (1.8) | (3.7) | (3.5)
Foreign currency translation | (0.9) | 1.8 | 0.6
Total recognized in OCI | (12.9) | (2.2) | (3.6)
Total recognized in net periodic benefit cost and OCI | (13.3) | 0.5 | 0.7
Pension benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | (2.3) | 1.2 | 2.4
Pension benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | 1.9 | 1.5 | 1.9
Other retirement benefits |  |  |
Net periodic benefit cost: |  |  |
Service cost | 0.0 | 0.0 | 0.0
Interest cost | 0.2 | 0.2 | 0.2
Expected return on plan assets | 0.0 | 0.0 | 0.0
Amortization of prior service credit | (0.4) | (0.7) | (0.7)
Amortization of actuarial loss (gain) | (1.6) | (1.9) | (2.3)
Settlement loss | 0.0 | 0.0 | 0.0
Net periodic benefit cost | (1.8) | (2.4) | (2.8)
Other changes in plan assets and benefit obligations recognized in OCI, pre-tax: |  |  |
Net (gain) loss arising during period | (0.9) | (0.4) | 0.1
Prior service credit arising during period | 0.0 | 0.0 | 0.0
Amortization of prior service credit | 0.4 | 0.7 | 0.7
Amortization of actuarial (loss) gain | 1.6 | 1.9 | 2.3
Settlement loss | 0.0 | 0.0 | 0.0
Foreign currency translation | 0.0 | 0.0 | 0.0
Total recognized in OCI | 1.1 | 2.2 | 3.1
Total recognized in net periodic benefit cost and OCI | (0.7) | (0.2) | 0.3
Other retirement benefits | United States |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | (1.8) | (2.4) | (2.8)
Other retirement benefits | International plans |  |  |
Net periodic benefit cost: |  |  |
Net periodic benefit cost | $ 0.0 | $ 0.0 | $ 0.0

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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