Note 13 - Retirement Benefit Plans - Accumulated Benefit Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
UNITED STATES | Nonqualified Plan [Member]
Accumulated benefit obligation	$ 1.1	$ 1.2
Foreign Plan [Member] | Pension Plan [Member] | UK Pension Plan [Member]
Accumulated benefit obligation	11.4	12.2
Foreign Plan [Member] | Pension Plan [Member] | German Pension Plan [Member]
Accumulated benefit obligation	1.0	1.2
Foreign Plan [Member] | Pension Plan [Member] | Italian Pension Plan [Member]
Accumulated benefit obligation	$ 3.7	$ 4.2