| Note 13 - Retirement Benefit Plans The following table sets forth the net periodic benefit cost for the Company’s defined benefit pension plans. The amounts for the three and six months ended June 30, 2018 are based on calculations prepared by the Company's actuaries and represent the Company’s best estimate of the respective period’s proportionate share of the amounts to be recorded for the year ending December 31, 2018. | | | | | | | | | | | | | | | | | | | | | U.S. Plans | International Plans | Total | | Three Months Ended
June 30, | Three Months Ended
June 30, | Three Months Ended
June 30, | | 2018 | 2017 | 2018 | 2017 | 2018 | 2017 | Components of net periodic benefit cost: | | | | | | | Service cost | $ | 3.2 |
| $ | 3.0 |
| $ | 0.4 |
| $ | 0.4 |
| $ | 3.6 |
| $ | 3.4 |
| Interest cost | 5.8 |
| 6.1 |
| 1.8 |
| 1.9 |
| 7.6 |
| 8.0 |
| Expected return on plan assets | (7.3 | ) | (7.0 | ) | (2.9 | ) | (2.7 | ) | (10.2 | ) | (9.7 | ) | Amortization of prior service cost | 0.4 |
| 0.4 |
| — |
| — |
| 0.4 |
| 0.4 |
| Recognition of actuarial gains | (2.4 | ) | — |
| — |
| — |
| (2.4 | ) | — |
| Net periodic benefit cost | $ | (0.3 | ) | $ | 2.5 |
| $ | (0.7 | ) | $ | (0.4 | ) | $ | (1.0 | ) | $ | 2.1 |
|
| | | | | | | | | | | | | | | | | | | | | U.S. Plans | International Plans | Total | | Six Months Ended
June 30, | Six Months Ended
June 30, | Six Months Ended
June 30, | | 2018 | 2017 | 2018 | 2017 | 2018 | 2017 | Components of net periodic benefit cost: | | | | | | | Service cost | $ | 6.4 |
| $ | 6.1 |
| $ | 0.8 |
| $ | 0.8 |
| $ | 7.2 |
| $ | 6.9 |
| Interest cost | 11.7 |
| 12.3 |
| 3.7 |
| 3.7 |
| 15.4 |
| 16.0 |
| Expected return on plan assets | (14.6 | ) | (14.0 | ) | (5.9 | ) | (5.4 | ) | (20.5 | ) | (19.4 | ) | Amortization of prior service cost | 0.8 |
| 0.7 |
| — |
| — |
| 0.8 |
| 0.7 |
| Recognition of actuarial (gains) losses | (2.4 | ) | 4.4 |
| — |
| — |
| (2.4 | ) | 4.4 |
| Net periodic benefit cost | $ | 1.9 |
| $ | 9.5 |
| $ | (1.4 | ) | $ | (0.9 | ) | $ | 0.5 |
| $ | 8.6 |
|
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