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Pension and Other Post-retirement Benefits (Tables) | 12 Months Ended
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Dec. 31, 2017
Schedule of Changes in Benefit Obligation, Plan Assets and Funded Status of Defined Benefit Pension and Post Retirement Benefit Plans | The following tables present the changes in benefit obligations, plan assets and funded status for domestic pension and post-retirement plans and the components of net periodic benefit costs.
|  | Pension Benefits |  |  | Post-retirement Benefits |
Years ended December 31 (dollars in millions) |  | 2017 |  |  | 2016 |  |  | 2017 |  |  | 2016 |
Accumulated benefit obligation (ABO) at December 31 |  | $ | 921.8 |  |  | $ | 894.3 |  |  |  | N/A |  |  |  | N/A |
Change in projected benefit obligations (PBO) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
PBO at beginning of year |  | $ | (895.8 | ) |  | $ | (892.9 | ) |  | $ | (6.6 | ) |  | $ | (6.6 | )
Service cost |  |  | (1.8 | ) |  |  | (1.8 | ) |  |  | (0.1 | ) |  |  | (0.1 | )
Interest cost |  |  | (30.0 | ) |  |  | (30.6 | ) |  |  | (0.3 | ) |  |  | (0.2 | )
Participant contributions |  |  | — |  |  |  | — |  |  |  | (0.1 | ) |  |  | — |
Plan amendments |  |  | — |  |  |  | (0.7 | ) |  |  | — |  |  |  | — |
Actuarial loss including assumption changes |  |  | (54.3 | ) |  |  | (31.0 | ) |  |  | (1.1 | ) |  |  | (0.2 | )
Benefits paid |  |  | 59.2 |  |  |  | 61.2 |  |  |  | 0.6 |  |  |  | 0.5 |
PBO at end of year |  | $ | (922.7 | ) |  | $ | (895.8 | ) |  | $ | (7.6 | ) |  | $ | (6.6 | )
Change in fair value of plan assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Plan assets at beginning of year |  | $ | 787.0 |  |  | $ | 759.0 |  |  | $ | — |  |  | $ | — |
Actual return on plan assets |  |  | 116.5 |  |  |  | 57.0 |  |  |  | — |  |  |  | — |
Contribution by the company |  |  | 30.5 |  |  |  | 32.2 |  |  |  | 0.4 |  |  |  | 0.5 |
Participant contributions |  |  | — |  |  |  | — |  |  |  | 0.1 |  |  |  | — |
Benefits paid |  |  | (59.2 | ) |  |  | (61.2 | ) |  |  | (0.5 | ) |  |  | (0.5 | )
Plan assets at end of year |  | $ | 874.8 |  |  | $ | 787.0 |  |  | $ | — |  |  | $ | — |
Funded status |  | $ | (47.9 | ) |  | $ | (108.8 | ) |  | $ | (7.6 | ) |  | $ | (6.6 | )
Amount recognized in the balance sheet |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  | $ | (0.5 | ) |  | $ | (0.5 | ) |  | $ | (0.3 | ) |  | $ | (0.4 | )
Non-current liabilities |  |  | (47.4 | ) |  |  | (108.3 | ) |  |  | (7.3 | ) |  |  | (6.2 | )
Net pension liability at end of year |  | $ | (47.9 | )* |  | $ | (108.8 | )* |  | $ | (7.6 | ) |  | $ | (6.6 | )
Amounts recognized in accumulated other comprehensive loss before tax |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net actuarial loss (gain) |  | $ | 451.8 |  |  | $ | 473.5 |  |  | $ | (0.8 | ) |  | $ | (2.0 | )
Prior service cost |  |  | (0.5 | ) |  |  | (0.9 | ) |  |  | (2.6 | ) |  |  | (2.9 | )
Total recognized in accumulated other comprehensive loss |  | $ | 451.3 |  |  | $ | 472.6 |  |  | $ | (3.4 | ) |  | $ | (4.9 | )
* | In addition, the Company has a liability for a foreign pension plan of $0.2 million and $0.2 million at December 31, 2017 and 2016, respectively.
Schedule of Net Periodic Benefit Cost |
|  | Pension Benefits |  |  | Post-retirement Benefits |
Years ended December 31 (dollars in millions) |  | 2017 |  |  | 2016 |  |  | 2015 |  |  | 2017 |  |  | 2016 |  |  | 2015 |
Net periodic benefit cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 1.8 |  |  | $ | 1.8 |  |  | $ | 1.9 |  |  | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | 0.1 |
Interest cost |  |  | 30.0 |  |  |  | 30.6 |  |  |  | 37.6 |  |  |  | 0.3 |  |  |  | 0.2 |  |  |  | 0.3 |
Expected return on plan assets |  |  | (58.4 | ) |  |  | (55.9 | ) |  |  | (57.5 | ) |  |  | — |  |  |  | — |  |  |  | — |
Amortization of unrecognized: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net actuarial loss (gain) |  |  | 17.9 |  |  |  | 17.7 |  |  |  | 19.1 |  |  |  | (0.1 | ) |  |  | (0.2 | ) |  |  | (0.1 | )
Prior service cost |  |  | (0.4 | ) |  |  | (1.1 | ) |  |  | (1.0 | ) |  |  | (0.4 | ) |  |  | (0.4 | ) |  |  | (0.4 | )
Curtailment and other one-time charges |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Defined-benefit plan (income) cost |  |  | (9.1 | ) |  |  | (6.9 | ) |  |  | 0.1 |  |  | $ | (0.1 | ) |  | $ | (0.3 | ) |  | $ | (0.1 | )
Various U.S. defined contribution plans cost |  |  | 12.0 |  |  |  | 11.6 |  |  |  | 10.8 |  |  |  |  |  |  |  |  |  |  |  |  |
|  | $ | 2.9 |  |  | $ | 4.7 |  |  | $ | 10.9 |  |  |  |  |  |  |  |  |  |  |  |  |
Other changes in plan assets and projected benefit obligation recognized in other comprehensive loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net actuarial (gain) loss |  | $ | (3.8 | ) |  | $ | 29.9 |  |  | $ | 17.2 |  |  | $ | 1.1 |  |  | $ | 0.2 |  |  | $ | — |
Amortization of net actuarial (loss) gain |  |  | (17.9 | ) |  |  | (17.7 | ) |  |  | (19.1 | ) |  |  | 0.1 |  |  |  | 0.2 |  |  |  | 0.1 |
Prior service cost |  |  | — |  |  |  | 0.6 |  |  |  | 2.5 |  |  |  | — |  |  |  | — |  |  |  | (3.7 | )
Amortization of prior service cost |  |  | 0.5 |  |  |  | 1.1 |  |  |  | 1.0 |  |  |  | 0.4 |  |  |  | 0.4 |  |  |  | 0.4 |
Total recognized in other comprehensive loss |  |  | (21.2 | ) |  |  | 13.9 |  |  |  | 1.6 |  |  |  | 1.6 |  |  |  | 0.8 |  |  |  | (3.2 | )
Total recognized in net periodic (benefit) cost and other comprehensive loss |  | $ | (30.3 | ) |  | $ | 7.0 |  |  | $ | 1.7 |  |  | $ | 1.5 |  |  | $ | 0.5 |  |  | $ | (3.3 | )
Schedule of Actuarial Assumptions Used To Determine Benefit Obligations | Actuarial assumptions used to determine benefit obligations at December 31 are as follows:
|  | Pension Benefits |  |  | Post-retirement Benefits |
|  | 2017 |  |  | 2016 |  |  | 2017 |  |  | 2016 |
Discount rate |  |  | 3.65 | % |  |  | 4.15 | % |  |  | 3.79 | % |  |  | 4.33 | %
Average salary increases |  |  | n/a |  |  |  | 4.00 | % |  |  | n/a |  |  |  | n/a |
Schedule of Actuarial Assumptions Used To Determine Net Periodic Benefit Cost | Actuarial assumptions used to determine net periodic benefit cost for the year ended December 31 are as follows:
|  | Pension Benefits |  |  | Post-retirement Benefits |
Years ended December 31 |  | 2017 |  |  | 2016 |  |  | 2015 |  |  | 2017 |  |  | 2016 |  |  | 2015 |
Discount rate |  |  | 4.15 | % |  |  | 4.40 | % |  |  | 4.05 | % |  |  | 4.40 | % |  |  | 4.55 | % |  |  | 4.00 | %
Expected long-term return on plan assets |  |  | 7.50 | % |  |  | 7.50 | % |  |  | 7.75 | % |  |  | n/a |  |  |  | n/a |  |  |  | n/a |
Rate of compensation increase |  |  | 4.00 | % |  |  | 4.00 | % |  |  | 4.00 | % |  |  | 4.00 | % |  |  | 4.00 | % |  |  | 4.00 | %
Schedule of Health Care Cost Trend Rates | Assumed health care cost trend rates as of December 31 are as follows:
|  | 2017 |  |  | 2016 |
Health care cost trend rate assumed for next year |  |  | 6.50 | % |  |  | 6.50 | %
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) |  |  | 5.00 | % |  |  | 5.00 | %
Year that the rate reaches the ultimate trend rate |  |  | 2021 |  |  |  | 2021 |
Schedule of Weighted Asset Allocations by Asset Category | The Company’s pension plan weighted asset allocations as of December 31 by asset category are as follows:
Asset Category |  | 2017 |  |  | 2016 |
Equity securities |  |  | 45 | % |  |  | 48 | %
Debt securities |  |  | 43 |  |  |  | 37 |
Real estate |  |  | 9 |  |  |  | 10 |
Private equity |  |  | 2 |  |  |  | 4 |
Other |  |  | 1 |  |  |  | 1 |
|  |  | 100 | % |  |  | 100 | %
Schedule of Fair Value Measurement of Plan Assets | The following tables present the fair value measurement of the Company’s plan assets as of December 31, 2017 and 2016 (dollars in millions):
|  |  |  |  | December 31, 2017 |
Asset Category |  | Total |  |  | Quoted Prices in Active Markets for Identical Contracts (Level 1) |  |  | Significant Other Observable Inputs (Level 2) |  |  | Significant Non- observable Inputs (Level 3) |
Short-term investments |  | $ | 15.8 |  |  | $ | 2.0 |  |  | $ | 13.8 |  |  | $ | — |
Equity securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stocks |  |  | 220.3 |  |  |  | 220.3 |  |  |  | — |  |  |  | — |
Commingled equity funds |  |  | 121.5 |  |  |  | — |  |  |  | 121.5 |  |  |  | — |
Fixed income securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. treasury securities |  |  | 46.0 |  |  |  | 46.0 |  |  |  | — |  |  |  | — |
Other fixed income securities |  |  | 219.9 |  |  |  | — |  |  |  | 219.9 |  |  |  | — |
Commingled fixed income funds |  |  | 99.8 |  |  |  | — |  |  |  | 99.8 |  |  |  | — |
Other types of investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mutual funds |  |  | 51.8 |  |  |  | — |  |  |  | 51.8 |  |  |  | — |
Real estate funds |  |  | 77.8 |  |  |  | — |  |  |  | — |  |  |  | 77.8 |
Private equity |  |  | 20.9 |  |  |  | — |  |  |  | — |  |  |  | 20.9 |
Total fair value of plan asset investments |  | $ | 873.8 |  |  | $ | 268.3 |  |  | $ | 506.8 |  |  | $ | 98.7 |
Non-investment plan assets |  |  | 1.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Total plan assets |  | $ | 874.8 |  |  |  |  |  |  |  |  |  |  |  |  |
|  |  |  |  | December 31, 2016 |
Asset Category |  | Total |  |  | Quoted Prices in Active Markets for Identical Contracts (Level 1) |  |  | Significant Other Observable Inputs (Level 2) |  |  | Significant Non- observable Inputs (Level 3) |
Short-term investments |  | $ | 28.7 |  |  | $ | 1.1 |  |  | $ | 7.9 |  |  | $ | 19.7 |
Equity securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stocks |  |  | 254.0 |  |  |  | 254.0 |  |  |  | — |  |  |  | — |
Commingled equity funds |  |  | 105.6 |  |  |  | — |  |  |  | 105.6 |  |  |  | — |
Fixed income securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. treasury securities |  |  | 97.6 |  |  |  | 97.6 |  |  |  | — |  |  |  | — |
Other fixed income securities |  |  | 102.6 |  |  |  | — |  |  |  | 102.6 |  |  |  | — |
Commingled fixed income funds |  |  | 90.3 |  |  |  | — |  |  |  | 90.3 |  |  |  | — |
Other types of investments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Mutual funds |  |  | 4.5 |  |  |  | — |  |  |  | 4.5 |  |  |  | — |
Real estate funds |  |  | 74.3 |  |  |  | — |  |  |  | — |  |  |  | 74.3 |
Private equity |  |  | 28.0 |  |  |  | — |  |  |  | — |  |  |  | 28.0 |
Total fair value of plan asset investments |  | $ | 785.6 |  |  | $ | 352.7 |  |  | $ | 310.9 |  |  | $ | 122.0 |
Non-investment plan assets |  |  | 1.4 |  |  |  |  |  |  |  |  |  |  |  |  |
Total plan assets |  | $ | 787.0 |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Reconciliation of Fair Value Measurements Using Significant Unobservable Inputs | The following table presents a reconciliation of the fair value measurements using significant unobservable inputs (Level 3) as of December 31, 2017 and 2016 (dollars in millions):
|  | Short term investments |  |  | Real estate funds |  |  | Private equity |  |  | Total |
Balance at December 31, 2015 |  | $ | 12.4 |  |  | $ | 70.9 |  |  | $ | 34.3 |  |  | $ | 117.6 |
Actual return (loss) on plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Relating to assets still held at the reporting date |  |  | — |  |  |  | 3.4 |  |  |  | (5.5 | ) |  |  | (2.1 | )
Relating to assets sold during the period |  |  | — |  |  |  | — |  |  |  | 9.3 |  |  |  | 9.3 |
Purchases, sales and settlements |  |  | 7.3 |  |  |  | — |  |  |  | (10.1 | ) |  |  | (2.8 | )
Balance at December 31, 2016 |  |  | 19.7 |  |  |  | 74.3 |  |  |  | 28.0 |  |  |  | 122.0 |
Actual return (loss) on plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Relating to assets still held at the reporting date |  |  | — |  |  |  | 3.5 |  |  |  | (5.6 | ) |  |  | (2.1 | )
Relating to assets sold during the period |  |  | — |  |  |  | — |  |  |  | 7.8 |  |  |  | 7.8 |
Purchases, sales and settlements |  |  | (19.7 | ) |  |  | — |  |  |  | (9.3 | ) |  |  | (29.0 | )
Balance at December 31, 2017 |  | $ | — |  |  | $ | 77.8 |  |  | $ | 20.9 |  |  | $ | 98.7 |
Schedule of Estimated Future Payments | The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid:
Years ending December 31 (dollars in millions) |  | Pension Benefits |  |  | Post-retirement Benefits |
2018 |  | $ | 60.5 |  |  | $ | 0.3 |
2019 |  |  | 66.6 |  |  |  | 0.4 |
2020 |  |  | 68.5 |  |  |  | 0.4 |
2021 |  |  | 59.3 |  |  |  | 0.4 |
2022 |  |  | 58.6 |  |  |  | 0.4 |
2023 – 2027 |  |  | 285.6 |  |  |  | 2.2 |

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- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the change in the benefit obligation of pension plans and/or other employee benefit plans from the beginning to the end of the period, showing separately, if applicable, the effects of the following: service cost, interest cost, contributions by plan participants, actuarial gains and losses, foreign currency exchange rate changes, benefits paid, plan amendments, business combinations, divestitures, curtailments, settlements, and special and contractual termination benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2439-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2410-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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